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Mayomi, Ikusemoran, Didams Gideon, and Michael Abashiya. "Analysis of the Spatial Distribution of Geology and Pedologic Formations in Gombe State, North Eastern Nigeria." Journal of Geography and Geology 10, no. 1 (February 27, 2018): 83. http://dx.doi.org/10.5539/jgg.v10n1p83.
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This paper focused on the mapping and analysis of the spatial distribution of the geology and soils in Gombe State. The ever rapid rise in population of the country has called for the need for expansion of agricultural activities which necessitates an in-depth knowledge of the spatial location of soil types for agricultural related activities. There is also the need to explore the environment for possible endowments of mineral resources which can be exploited to meet the economic demands of the populace. The soil and geology maps of Gombe State were extracted from existing soil and geology maps of Nigeria, obtained from Food and Agricultural Organization (FAO)/United Nations Education, Scientific and Cultural Organization (UNESCO)/International Soil Reference and Information Center (ISRIC) and Nigeria Geological Survey Agency (NGSA) respectively. The soil and geology types were digitized as polygon, while other important features such as LGA boundaries, state boundaries were also digitized and overlain on the two generated maps (soils and geology). The clip sub module of the ArcGIS was used to delineate each of the LGAs in both maps, that is, extraction of each LGA as well as the soil and geology units in each of the LGAs. The area in square kilometers of the soils and geology units in the entire state and in each LGA were obtained through the use of the area calculation module of the ArcGIS. The result of the study revealed that Gombe State consists of fourteen (14) geologic units. Among them, the KerriKerri which comprised of sandstone, shale and clay geologic unit covers almost half (42.75%) of the State. Limestone and Shale of the Pindiga formation which are principally used for cement making are found mainly in Funakaye LGA which is the home of Ashaka Cement. It was also found out that there are eleven soil units in the state with Nitisols almost covering half of the state. It was recommended that the generated soil and geologic maps of the State are expected to be considered for mineral exploration and crop suitability assessments in order to reduce time, cost and energy that would likely be incurred if the entire state is assessed.
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Zagorchev, Ivan. "Introduction to the geology of SW Bulgaria." Geologica Balcanica 31, no. 1-2 (June 30, 2001): 3–52. http://dx.doi.org/10.52321/geolbalc.31.1-2.3.
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The geologic structure of Southwest Bulgaria is characterized by a complex Mid Cretaceous pile of thrust sheets, a complex system of horsts and grabens of Palaeogene age, and a neotectonic (Neogene - Quaternary) pattern dominated by the Strouma rift system and the Serbo-Macedonian neotectonic swell. Amphibolite-facies metamorphic rocks belong to the Ograzhdenian (Prerhodopian) and Rhodopian Supergroup and the Osogovo “Formation”. The last intensive metamorphic event is proven to be of Cadomian age, and later superimposed metamorphic and deformation events have had a local occurrence. The greenschist-facies Frolosh Formation (Vendian - Lower Cambrian) has a diabasephyllitoid composition and is typical for the Strouma tectonic superunit. The basement of the latter Ograzhdenian Supergroup, Osogovo “Formation”, Frolosh Formation) is covered with a major depositional unconformable contact by sedimentary complexes of Ordovician (only in the Bosilegrad District in Yugoslavia) and Permian and Triassic age. Palaeozoic formations of Ordovician to Devonian age are present only in the thrust sheets of the Morava superunit, and in parts of the southern edge of the Srednogorie zone. Permian formations (mostly continental red beds) have a restricted occurrence. The Triassic (only in the Strouma superunit and parts of the Srednogorie) consists of the Petrohan Terrigenous Group (continental red beds), the Iskur Carbonate Group (marine) and the Moesian Group (marine red beds). After folding, uplift and erosion, the transgressive Jurassic formations have been formed in several different environments, in latest Jurassic - earliest Cretaceous times represented by the carbonate platform to the North, and the Nish-Troyan flysch trough. The principal orogenesis occurred in Mid Cretaceous times, and Upper Cretaceous sedimentary formations are present only in parts of the Srednogorie zone. Late Cretaceous intrusive rocks are known from the Srednogorie (of mantle origin) and in Pirin (crustal granitoids). The Late Cretaceous orogenesis formed the Srednogorie superunit (to the North) and the Morava-Rhodope superunit (to the South). Thus, the Alpine structure consists of the following principal tectonic units: Late Cretaceous Srednogorie superunit (with fragments from the Mid-Cretaceous Lyubash, Golo-burdo, Melovete, Radomir and Verila units) and Morava-Rhodope superunit with the Mid-Cretaceous Morava superunit and Ograzhden unit (allochthonous), Strouma superunit (Louzhnitsa-Trun and Osogovo-Vlahina unit), Rhodope and Pirin-Pangaion superunit. The Palaeogene and Neogene formations have the character of a neoautochthone that is controlled by the Late Alpine and neotectonic block movements.
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Solihin, Cece, Arizal Taufik, Firman Hadi Muhamad, and Rena Denya. "Studi Geofisika Untuk Menentukan Batas Formasi Jampang dan Formasi Ciletuh di Kawasan Geopark Ciletuh." Wahana Fisika 2, no. 2 (December 28, 2017): 31. http://dx.doi.org/10.17509/wafi.v2i2.9373.
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Kawasan Ciletuh memiliki struktur geologi yang khas dan unik serta memiliki aneka ragam batuan yang tersebar. Pandangan umum dari ilmu kebumian kawasan ini sangat menarik untuk dipelajari karena geologi kawasan ini terbentuk tidak lepas dari aktivitas tektonik regional Jawa Barat. Studi geofisika sangat berguna dalam menganalisa struktur geologi bawah permukaan tanah di kawasan Ciletuh. Metode geofisika yang digunakan bertujuan untuk mengamati dan menganalisis struktur geologi batuan permukaan. Serta, tujuan utama dari penelitian ini untuk menentukan batas formasi Jampang dengan formasi Ciletuh. Penelitian ini digunakan pengambilan data dengan metode Geolistrik, Magnetik dan Ground Penetrating Radar (GPR) di daerah Tamanjaya, kawasan Ciletuh dengan lintasan yang berbeda. Berdasarkan interpretasi geolistrik pada software Res2Dinv 2D diperoleh struktur bawah permukaan berupa lapisan batuan pasir. Pada hasil interpretasi metode GPR pola perambatan serta kecepatan rambat gelombang elektromagnetik untuk dua lintasan GPR memiliki perbedaan struktur batuan yaitu batuan pasir kasar, kerikil dan endapan. Sedangkan hasil interpretasi magnetik mengindikasi perbedaan struktur batuan dalam bawah permukaan berdasarkan anomali magnetik. Berdasarkan geologi regional formasi Jampang bawah didominasi oleh batuan pasir halus. Sedangkan formasi Ciletuh didominasi oleh batuan pasir kasar yang berumur lebih tua. Sehingga batas formasi Jampang dengan batas formasi Ciletuh dapat diperkirakan pada lintasan GPR dan Magnetik. Kata Kunci : Formasi Jampang; Formasi Ciletuh; Geolistrik; GPR dan MagnetikThe Ciletuh region has a distinctive and unique geological structure and also has a various of rocks scattered. The general view of the geography of this region is very interesting to learn because the geology of this region formed can not be sparated from the regional tectonic activity of west java. Geophysical studies are very useful in analyzing the subsurface geological structures in the Ciletuh region. The geophysical methods used aims to observe and analyze the geological structure of surface rocks. As well, the main purpose of this research is to determine the boundary of Jampang formation with Ciletuh formation. This research used data retrieval using Geoelectric, Magnetic and Ground Penetrating Radar (GPR) methods in Tamanjaya area, Ciletuh area with a different trajectory. Based on the geoelectric interpretation from Res2Dinv of software, there is obtained a subsurface structure in the form of sandstone layer. The results of the interpretation of GPR methods, propagation patterns and electromagnetic wave velocity for 2 trajectories have structural abnormalities, ie sandstone rock, gravel and sediment. Whereas the results of magnetic interpretation indicate difference in surface rocks structure based on magnetic anomlies. Base on the regional geology of the lower Jampang formation is dominated by fine sand rock while the formation of Ciletuh is dominated by Rugged Sandstone rocks that was older. So the boundary of formation Jampang with baoundary formations Ciletuh can be estimate at GPR and Magnetic trajectory.Keywords : Jampang Formations; Ciletuh Formations; Geoeletric; GPR; and Magnetic
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Abdullah, Wan Hasiah, and Say Gee Sia. "Geology, resource potential and organic petrography of the Neogene coals in the Miri area of Northwest Sarawak, Malaysia." Warta Geologi 48, no. 2 (August 30, 2022): 66–71. http://dx.doi.org/10.7186/wg482202202.
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There are three coal-bearing geological formations in the Miri area, viz. the Belait Formation, the Lambir Formation, and the Liang Formation. Of the three coal-bearing geological formations, only the sub-bituminous B Tutoh coals from the Belait Formation, with an estimated resource of 203 million tonnes, are believed to be of economic potential. The Tutoh coals are dominated by vitrinite group, especially desmocollinite. The sub-bituminous B from the Lambir Formation and the lignite from Liang Formation are of low economic potential due to the limited area of the hosting formations.
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Ochoa, Carlos G., William Todd Jarvis, and Jesse Hall. "A Hydrogeologic Framework for Understanding Surface Water and Groundwater Interactions in a Watershed System in the Willamette Basin in Western Oregon, USA." Geosciences 12, no. 3 (February 25, 2022): 109. http://dx.doi.org/10.3390/geosciences12030109.
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A broad understanding of local geology and hydrologic processes is important for effective water resources management. The objectives of this project were to characterize the hydrogeologic framework of the Oak Creek Watershed (OCW) geographical area and examine the connections between surface water and groundwater at selected locations along the main stem of Oak Creek. The OCW area comprises the Siletz River Volcanic (SRV) Formation in the upper portion of the watershed and sedimentary rock formations in the valley. Past hydrologic and geologic studies and our field measurement data were synthesized to create a hydrogeologic framework of the watershed, including a geologic interpretation and a conceptual model of shallow, deep, and lateral groundwater flow throughout the OCW. The highly permeable geology of the SRV formation juxtaposed against the Willamette Basin’s sedimentary geology creates areas of opposing groundwater flow characteristics (e.g., hydraulic conductivity) in the watershed. The Corvallis Fault is the primary interface between these two zones and generally acts as a hydraulic barrier, deflecting groundwater flow just upstream of the fault interface. The extreme angle of the Corvallis Fault and adjacent less permeable sedimentary geology might facilitate subsurface bulk water storage in selected locations. The stream-aquifer relationships investigated showed gaining conditions are prominent in the upper watershed’s northern volcanic region and transition into neutral and losing conditions in the downstream southern sedimentary region in the valley. Agriculture irrigation seepage in the valley appeared to contribute to streamflow gaining conditions. Results from this case study contribute critical information toward enhancing understanding of local hydrogeologic features and potential for improved SW-GW resources management in areas near coastal ranges such as those found in the Pacific Northwest, USA.
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Scharf, Andreas, Frank Mattern, Mohammed Al-Wardi, Gianluca Frijia, Daniel Moraetis, Bernhard Pracejus, Wilfried Bauer, and Ivan Callegari. "Chapter 2 Tectonostratigraphy of the eastern part of the Oman Mountains." Geological Society, London, Memoirs 54, no. 1 (2021): 11–47. http://dx.doi.org/10.1144/m54.2.
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AbstractThis chapter provides comprehensive descriptions of 52 numbered formations/rock units of the Southeastern Oman Mountains, based on available literature. The oldest eight siliciclastic and carbonate formations are positioned below the ‘Hercynian’ Unconformity. The overlying formation (9–16) mostly represent carbonates which accumulated in a passive margin platform setting during or after the opening of the Neo-Tethys Ocean. The passive margin slope and platform collapsed during the late Cretaceous because of the obduction of the Semail Ophiolite along with the deep marine Hawasina sedimentary rocks. The collapsing passive margin interval was recorded within the syn-obductional Aruma Group (17; Muti Formation). Above this formation are the allochthonous units (18–42) of the tectonically lower Hawasina deep-sea basin and the structurally overlying Semail Ophiolite. The former contains Permian to Upper Cretaceous formations, while the latter is Cenomanian in age. Above the allochthonous rocks, the Neo-autochthonous formations were deposited, starting with the post-obductional uppermost Cretaceous Aruma Group (43; Al-Khod Formation) until the Quaternary deposits (52). All these formations/rock units are depicted on an accompanying map and stratigraphic chart.
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Mina, Chrokhan, and Rzger Abdula. "Palaeoenvironment Conditions During Deposition of Sargelu, Naokelekan, and Najmah Formations in Zey Gawara Area, Kurdistan Region, Iraq: Implications from Major and Trace Elements Proportions." Iraqi Geological Journal 56, no. 2B (August 31, 2023): 263–77. http://dx.doi.org/10.46717/igj.56.2b.21ms-2023-8-30.
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Palaeoenvironment conditions during deposition of Jurassic Sargelu, Naokelekan, and Najmah formations were studied based on samples from well Z1 in Zey Gawara area, Kurdistan region, Iraq. For the purpose of determining the palaeoredox, palaeoclimate conditions as well as palaeoweathering, tectonic setting, and provenance indices, the inorganic geochemical analysis to indicate the number and amount of different elements were performed. Based on the occurrence and proportionalities of trace elements e.g., V, Ni, Cu, Sr, the Sargelu Formation was probably accumulated in suboxic to anoxic conditions, while the Naokelekan and Najmah formations were deposited under the suboxic to dysoxic conditions. Relatively semiarid condition have suggested for Sargelu and Naokelekan formations, and relatively semi humid condition for Najmah Formation. The chemical index of alteration and the high plagioclase index of alteration suggest for modest to intense weathering source area for the Sargelu and Naokelekan formations. The index of chemical variability (<1) implies that the Sargelu, Naokelekan, and Najmah formations are probably immature sediments and deposited inside a tectonically active setting. Based on the tectonic indicators, the Sargelu and Naokelekan formations were deposited in an active continental margin, and the Najmah Formation was deposited in an oceanic island arc. The felsic for the Sargelu and Naokelekan and the felsic- intermediate igneous rocks were proposed as plausible source rocks for the Najmah Formation.
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Clausen, C. Heilmann, O. B. Nielsen, and F. Gersner. "Lithostratigraphy and depositional environments in the Upper Paleocene and Eocene of Denmark." Bulletin of the Geological Society of Denmark 33 (February 28, 1985): 287–323. http://dx.doi.org/10.37570/bgsd-1984-33-26.
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The Upper Paleocene and Eocene deposits of Denmark are described lithologically and are formally referred to six formations. The Upper Paleocene includes the Holmehus (new), 01st (new) and the Fur Formations. The Eocene comprises the R0snres Clay, Lillebrelt Clay and S0vind Marl Formations. The 01st Formation is divided into Haslund and Vrerum Members. The R0snres Clay Formation and the Lillebrelt Clay Formation are divided into twelve informal lithological units. The biostratigraphy (mainly calcareous nannoplankton and dinoflagellate zonations) of each formation is briefly outlined. Previously unknown volcanic ash layers are recognized in the Holmehus, R0snres Clay and the Lillebrelt Clay Formations, and a tephrachronology is established for the upper part of this ash sequence. The petrography and geochemistry of the formations are described and regional and vertical variations in the parameters are related to changes in terrigeneous supply and depositional environment. Variations in the thickness of the formations are related to differential subsidence. The depositional environment was marine to probably brackish and well below wave base. The sediments are mainly pelagic-like clays. Five major depositional phases are recognized, each represented by a formation (01st and Fur Formations being deposited during one phase). Phases of submarine non-deposition are identified at the base and top of the 01st Formation. The R0snres Clay and Lillebrelt Clay Formations include many widely distributed and regionally uniform, almost isochronous beds, each of a distinct lithology. They show that several widespread, rather sudden changes took place in a probably deep shelf environment with little regional variation. The changes are mainly ascribed to alterations in the marine circulation pattern.
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Yousif, Samir, and Ghalib Nouman. "Jurassic Geology of Kuwait." GeoArabia 2, no. 1 (January 1, 1997): 91–110. http://dx.doi.org/10.2113/geoarabia020191.
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ABSTRACT Until the late 1970s only one well penetrated the entire Jurassic section of Kuwait. A few other scattered wells partially penetrated it. During the 1980s an appreciable number of deep wells revealed that the Jurassic sequence is inverted with respect to the Cretaceous sequence and that the main Cretaceous arches were sites of Jurassic sedimentary troughs. This new interpretation marks a revolution in the existing concepts for Jurassic oil exploration in Kuwait. One of the most effective methods for defining of Jurassic structures is the isopach of the Upper Jurassic Gotnia Formation. The main Jurassic reservoirs include the Najmah, Sargelu and Marrat formations which were detected as a result of the exploration activities during the 1980s. Selective stratigraphic and structural cross-sections reveal the stratigraphic relationships of the Jurassic sediments.
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Bahr, Fadel, and Dave Keighley. "Chemostratigraphy of Cumberland Group (Pennsylvanian) strata influenced by salt tectonics, Joggins Fossil Cliffs UNESCO World Heritage Site, eastern Canada." Journal of Sedimentary Research 91, no. 9 (September 23, 2021): 969–85. http://dx.doi.org/10.2110/jsr.2020.152.
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ABSTRACT The Pennsylvanian stratigraphy of the western Cumberland Basin has been influenced by salt tectonics, specifically the formation of the Minudie Anticline, a salt wall. South of the Minudie Anticline, along the shoreline of the Joggins Fossil Cliffs UNESCO World Heritage Site, the post–Boss Point Formation succession comprises an ∼ 3 km succession of strata assigned to the Little River, Joggins, Springhill Mines, and Ragged Reef formations. North of the Minudie anticline, the Grande Anse Formation lies in angular unconformity on the Boss Point and basal Little River formations. Biostratigraphic studies have not been able to discern whether the Grande Anse Formation is equivalent to all, or just one, of the Joggins to Ragged Reef units south of the salt wall (the Minudie Anticline). To further investigate the relationship of the Grande Anse Formation with the units along the Joggins shoreline, forty sandstone samples from the post–Boss Point Fm strata were selected for a chemostratigraphic study, using inductively coupled plasma mass spectrometry (ICP-MS) to determine major-element compositions. Transformed ICP-MS data, subjected to a Kruskal-Wallis test and post-hoc tests, show that there is no significant difference between Grande Anse and Ragged Reef formations in the mean values of almost all analyzed elements. In contrast, there are significant differences when comparing these two units and the older Little River, Joggins, and Springhill Mines formations in the case of elements usually encountered in detrital mineral phases (Si, Al, Ti, Na, and Fe). Sandstones of the Grande Anse and Ragged Reef formations show greater compositional maturity than the Little River, Joggins, and Springhill Mines formations. This trend is explained by a gradual overall change in paleoclimate from semiarid conditions during deposition of the Little River Formation to humid conditions during deposition of the Grande Anse and Ragged Reef formations, causing greater chemical weathering of the sediment. These findings indicate that > 2 km of sediment (Little River, Joggins, and Springhill Mines formations) accumulated south of the salt wall during the major episode of salt diapirism, followed by erosion of any topographic high associated with the salt wall, and accumulation of a further > 500 m of sediment (the laterally equivalent Ragged Reef and Grand Anse formations), all within a timespan of only ∼ 2 Myr.
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Ma, Feng, Tingxin Li, Yun Zhou, Jin Cai, and Yongfeng Cai. "Paleoenvironment of Mesoproterozoic Gaoyuzhuang and Wumishan Formations, North China: New Insights from Geochemistry and Carbon and Oxygen Isotopes of Dolostones." Minerals 12, no. 9 (August 31, 2022): 1111. http://dx.doi.org/10.3390/min12091111.
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The Mesoproterozoic Gaoyuzhuang and Wumishan Formations are major geothermal reservoirs in the Hebei Province, North China. Compared to the exploration of geothermal resources and heat-controlling structures, carbon and oxygen isotopic records of the two formations are limited. Here, we present integrated field, petrological, geochemical, carbon, and oxygen isotopic data of carbonate rocks from the Gaoyuzhuang and Wumishan Formations. The Wumishan Formation is characterized by higher CaO and MgO contents and lower SiO2 contents than the Gaoyuzhuang Formation, indicating that the source of the Wumishan Formation likely contains less terrigenous clastic materials. The two formations have low total rare earth element contents, similar to marine carbonate rocks. They show different Eu and Ce anomalies, Al/(Al + Fe + Mn) and Fe/Ti ratios, and (Co + Ni + Cu) contents. They generally show similar carbon isotopic compositions, whereas the carbonate rocks of the middle-upper Gaoyuzhuang Formation show lower δ18O values than the samples from the Wumishan and lower Gaoyuzhuang Formations. These data suggest that the two formations have experienced different transgressive–regressive cycles and that their sedimentary environments varied and were unstable in different sedimentary periods. The middle-upper Gaoyuzhuang Formation was likely affected by hydrothermal fluids, whereas the Wumishan Formation is composed of normal seawater deposits. Integrated evidence reveals that both of the Mesoproterozoic Gaoyuzhuang and Wumishan Formations were deposited in rift environments caused by the breakup of the Columbia/Nuna supercontinent.
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Cooper, A. H., and S. G. Molyneux. "The age and correlation of Skiddaw Group (early Ordovician) sediments in the Cross Fell inlier (northern England)." Geological Magazine 127, no. 2 (March 1990): 147–57. http://dx.doi.org/10.1017/s0016756800013832.
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AbstractThe Skiddaw Group in the Cross Fell inlier comprises the Catterpallot Formation of latest Tremadoc or earliest Arenig age, the Murton Formation of Arenig age, and the Kirkland Formation of early Llanvirn age. Each of these formations can be correlated with formations in the Skiddaw Group of the Lake District. The faulted contact of the Catterpallot and Kirkland formations is the probable extension of the Causey Pike Fault (CPF), which separates two distinct sequences in the Skiddaw inlier of the northern Lake District. Contrasts across the CPF in the Cross Fell inlier reflect those seen in the Skiddaw inlier. The CPF is a major basement structure, separating markedly different successions in the Ordovician strata of northern England.
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Tsiaras, Stefanos, and Christos Domakinis. "Correlating Mushroom Habitats and Geology in Grevena Prefecture (Greece) with the Use of Geographic Information Systems (GIS)." International Journal of Agricultural and Environmental Information Systems 6, no. 2 (April 2015): 1–14. http://dx.doi.org/10.4018/ijaeis.2015040101.
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The aim of this study is to assess the relationship between geological background and habitats of mushrooms. The study area is Grevena, a Prefecture of Greece well known for the great variety of the fungal flora and its distinctive geology. Thematic maps of the study area were produced with the use of GIS, taking under consideration geological formations, elevation, ecosystems and land use. Findings provide evidence that certain mushrooms are more likely to be found in specific ecosystems. The connection between forest ecosystems and the geology of the study area is more apparent, as certain forest types are related with specific geological formations; due to the insignificant presence of grasslands and riverine settings in the study area, it is not possible to assess the role of the geological formation for these mushroom habitats.
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Hicks, N., and D. J. C. Gold. "A reinterpretation of the Archaean stratigraphy south of Nkandla, southern Kaapvaal Craton, South Africa: Geophysical and stratigraphic constraints on a sheared granitoid-greenstone remnant." South African Journal of Geology 124, no. 3 (September 1, 2021): 685–98. http://dx.doi.org/10.25131/sajg.124.0025.
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Abstract A new lithostratigraphic framework based upon a review of historic data, field mapping and remote sensing, including aerial photography, high-resolution airborne aeromagnetic and radiometric data, is proposed for the Archaean geology along the southeastern margin of the Kaapvaal Craton, South Africa. A synthesis of new and existing data reveals that previously accepted lithostratigraphic schemes require complete revision, with reinterpretations identifying multiple major shear zones and previously unidentified granitoid successions along the margin of the craton. In this new lithostratigraphic framework, lithologies of the Southern Syncline previously correlated with the Nsuze Group of the Pongola Supergroup, are redefined as greenstone lithologies associated with the Ilangwe Greenstone Belt. The geology of the Nkandla region can be subdivided into five distinct geophysical domains including: (i) an extension of the Ilangwe Greenstone Belt, (Domain 1) which is subdivided into; a lower volcanic succession, the Thathe Formation, comprising pillow and amygdaloidal volcanics; the adjoining Sabiza Formation, comprising pillow volcanics exposed in the southeast of the study area; the volcano-sedimentary Mtshwili Formation, which overlies the Thathe and Sabiza formations, consisting of quartz (sericite) schist, phyllite, metavolcanics and iron formation; the Nomangci Formation, which occurs as a region of highly deformed quartz-kyanite-sericite schists, and the Simbagwezi Formation, which comprises maroon to green phyllites and schists in the north of the study area. (ii) granitoids of the Impisi Granitoid Suite (Domain 2) which border the greenstone succession to the north, intruding the Nomangci and Simbagwezi formations. (iii) a southern complex of sheared granitoids termed the Umgabhi Granitoid Suite (Domain 3), which intrudes the Thathe, Sabiza and Mtshwili formations. (iv) The two remaining domains, comprise the Mesoproterozoic Mfongosi and Ntingwe Groups (Domain 4) and Mesoarchaean volcano-sedimentary sequences of the Pongola Supergroup (Domain 5).
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Karagkounis, Nikolaos, Benoît Latapie, Kevin Sayers, and Sainath Reddy Mulinti. "Geology and geotechnical evaluation of Doha rock formations." Geotechnical Research 3, no. 3 (September 2016): 119–36. http://dx.doi.org/10.1680/jgere.16.00010.
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Kovalenko, S. N., I. K. Dekabryov, A. A. Yuryev, and I. A. Bogdanova. "Educational field practice in geomapping at the Faculty of Geology of Irkutsk University." Geology and Environment 3, no. 2 (2023): 132–64. http://dx.doi.org/10.26516/2541-9641.2023.2.132.
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The article provides a detailed description of all geological formations represented by: ages from the Archean Acron to the Cenozoic Era; sedimentary rocks of different stratigraphic units, different-age magmatic complexes, metamorphic and dynamometamorphic rocks and the sequence of their formation; modern loose formations of slope, proluvial-gravel, lake, alluvial, glacial, solifluctional and others minerals and organic remains, folds and discontinuities of different morphology and genesis within several key areas of the Baikal region and the vicinity of Irkutsk, which have to be studied by students at the educational field practice on geomapping, after the second year of study at the University. In the process of geomapping students are trained in methods of mapping and cameral processing of all these geological formations and presenting the results in the form of a scientific and production report at the end of the practice.
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Antonijevic, Ivan, and Predrag Mijatovic. "The copper deposits of Bor, eastern Serbia: Geology and origin of the deposits." Annales g?ologiques de la Peninsule balkanique, no. 75 (2014): 59–74. http://dx.doi.org/10.2298/gabp1475059a.
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The copper deposits of Bor, volcanic activities in the area and relationship of minerals through time are presented by formations within the Cenomanian-Turonian range. Geology and age of the deposits are given in the geological-time order based on superposition of the Timok mineral-ore Formation and the underlying (Cenomanian) and fossiliferous overlying (Senonian) strata. The concept of dating Bor deposits the Turonian is discussed in this context. Bor deposits lie between the Cenomanian Krivelj Formation and the Senonian epiclastic Metovnica Formation. Embedded between the two formations is the Timok volcanogenic Formation. Described in this paper are principal members of the Timok Formation strata: volcanogenic and subvolcanogenic- intrusive rocks, a zone of hydrothermally altered rocks and main types of the Bor ore deposits: (a) Deposits of massive sulphide coppers; (b) Vein and stockwork-disseminated type of mineralisation; (c) Porphyry mineralisation; and (d) Reworked ore-clasts of copper sulphides of the Novo Okno deposit. Identified deposits, according to the Bor Geological Service records and published works, are systematized and summarized into three geographic units: (1) Group of deposits Severozapad (Brezanik); (2) Central Bor Deposits (Tilva Ros, Coka Dulkan, Tilva Mika, Borska Reka, and Veliki Krivelj) and many ore bodies; (3) Copper deposits Jugoistok (ore bodies X and J) and olistostrome deposit Novo Okno. Information given in this paper, the discussion on relative geologic age of the Bor deposit?s floor and roof in particular, support our concept that the process ceased before the Upper Turonian, and that age of the primary copper mineralization is Turonian.
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Adolphe, J. P., A. Hourimeche, J. F. Loubiere, J. Paradas, and F. Soleilhavoup. "Les formations carbonatees d'origine bacterienne; formations continentales d'Afrique du Nord." Bulletin de la Société Géologique de France V, no. 1 (January 1, 1989): 55–62. http://dx.doi.org/10.2113/gssgfbull.v.1.55.
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Surjono, Sugeng Sapto, Mohd Shafeea Leman, Che Aziz Ali, Kamal Roslan Mohamed, and Fathan Hanifi Mada M. "Petrogenesis and depositional environment of paleozoic Sedili and Pengerang Volcaniclastics in East Johor Basin, Peninsular Malaysia." E3S Web of Conferences 76 (2019): 04009. http://dx.doi.org/10.1051/e3sconf/20197604009.
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Volcaniclastic rocks in East Johor Basin are found in a relatively great abundance comprising Sedili and Pengerang Formations excluding the metamorphics, siliciclastics, and granites. Since the volcaniclastic rocks are found in a different formation, this study aims to find out the characteristics of each rock. Geology, petrography, and geochemical analyses were elaborated to reveal the petrogenesis and depositional environment in the studied area on the basis of fieldwork data and 24 samples collected from outcrops. The Sedili and Pengerang Formations are dominated by acidic rocks of rhyolite, rhyodacite, ignimbrite, and lava classifiied into calc-alkaline magma series which indicates a subduction-related product. Moreover, those acidic rocks are grouped into active continental margin. Eventhough volcanic rocks in Sedili and Pengerang Formations exhibit similar characteristics, they are different in several major contents. Therefore, it is inferred that both Sedili and Pengerang Formations were deposited in different phase. Coincidentally, depositional environment of both formations is also distinct. Sedili Formation were deposited in the subaerial to shallow marine, meanwhile, Pengerang Formation is interpreted to be deposited in deeper depositional setting.
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Clemmensen, Lars B., Dennis W. Kent, Malte Mau, Octávio Mateus, and Jesper Milàn. "Triassic lithostratigraphy of the Jameson Land Basin (central East Greenland), with emphasis on the new Fleming Fjord Group." Bulletin of the Geological Society of Denmark 68 (June 5, 2020): 95–132. http://dx.doi.org/10.37570/bgsd-2020-68-05-rev.
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The lithostratigraphy of the Triassic deposits of the Jameson Land Basin in central East Greenland is revised. The new Scoresby Land Supergroup is now composed of the Wordie Creek, Pingo Dal, Gipsdalen and Fleming Fjord Groups. This paper only deals with the lithostratigraphy of the late Early-Late Triassic continental deposits of the latter three groups with emphasis on the vertebratebearing Fleming Fjord Group. The new Pingo Dal Group consists of three new formations, the Rødstaken, Paradigmabjerg and Klitdal Formations (all elevated from members), the new Gipsdalen Group consists of three new formations, the Kolledalen, Solfaldsdal (with the new Gråklint Member) and Kap Seaforth Formations (all elevated from members), and the new Fleming Fjord Group is subdivided into three new formations, the Edderfugledal, Malmros Klint and Ørsted Dal Formations (all elevated from members). The Edderfugledal Formation contains two cyclic bedded, lacustrine members, a lowermost Sporfjeld Member (elevated from beds), and an uppermost Pingel Dal Member (elevated from beds). The lacustrine red beds of the Malmros Klint Formation are not subdivided. The lacustrine and fluvial Ørsted Dal Formation contains three new members. In the eastern and central part of the basin, the formation is initiated by cyclic bedded, red lacustrine mudstones of the Carlsberg Fjord Member (elevated from beds), while in the northwestern part of the basin the lowermost part of the formation is composed of grey fluvial conglomerates and sandstones with subordinate red mudstones of the Bjergkronerne Member (elevated from beds). The uppermost part of the formations in most of the basin is composed of cyclic bedded, variegated lacustrine mudstones and grey to yellowish marlstones of the Tait Bjerg Member (elevated from beds). The sediments in the Fleming Fjord Group contain remains of a rich and diverse vertebrate fauna including dinosaurs, amphibians, turtles, aeotosaurs, pterosaurs, phytosaurs and mammaliaforms. Most vertebrate bones have been found in uppermost Malmros Klint Formation, and in the Carlsberg Fjord and Tait Bjerg Members. The Norian–early Rhaetian, lacustrine Fleming Fjord Group was deposited at about 41° N on the northern part of the supercontinent Pangaea. Lacustrine sedimentation was controlled by seasonal as well as longer-term (orbital) variation in precipitation. Precipitation was probably brought to the basin by southwesterly winds. The lacustrine sediments of the uppermost Fleming Fjord Group show deposition during increasingly humid conditions changing the lake environment from an ephemeral lake-steppe area to a perennial lake. This evolution of lake environment suggests a change from a winter-wet temperate climate to one with precipitation throughout the year.
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Oszczypko-Clowes, Marta. "Reworked nannofossils from the Lower Miocene deposits in the Magura Nappe (Outer Western Carpathians, Poland)." Geologica Carpathica 63, no. 5 (November 13, 2012): 407–24. http://dx.doi.org/10.2478/v10096-012-0032-4.
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Abstract Studies, based on calcareous nannofossils, proved that the level of reworked microfossils had so far been underestimated. More recently detailed quantitative studies of calcareous nannoplankton of the Magura, Malcov, Zawada and Kremna formations from the Magura Nappe in Poland documented a degree of nannofossil recycling among those formations. In the Late Eocene-Early Oligocene pelagic Leluchów Marl Member of the Malcov Formation the level of redeposition is very low (0-3.80 %), however, in the flysch deposits of the Malcov Formation reworking increased to 31.4 %. Late Oligocene through Early Miocene “molasse” type deposits of the Zawada and Kremna formations contain 43.7-69.0 % of reworked nannofossils. Quantitative analyses of the reworked assemblages confirmed the domination of Paleogene nannofossil species over Cretaceous ones. The most abundant, reworked assemblages belong to the Early- Middle Eocene age.
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Al-Banna, Ahmed, Hiba Tareq, and Ghazi Al-Sharaa. "New Equations to Determine Shear Velocity from Compressional Velocity in Hf-2 Well, Halfaya Oil Field." Iraqi Geological Journal 55, no. 1B (February 28, 2022): 38–48. http://dx.doi.org/10.46717/igj.55.1b.4ms-2022-02-20.
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The most important characters of the rock formations are shear and compression velocities, which are used to calculate elastic moduli. The geomechanical properties can be used to evaluate reservoir stability or to calibrate velocity and time/depth conversion, synthetic seismogram and other important applications. The aim of this study is to use the first order least square method to obtain an empirical equation to determine the shear velocity from compressional velocity for Mishrif, Rumaila, Ahmadi, and Mauddud formations in Hf-2 well. The obtained equations depend on sonic log and dipole shear sonic imager data of Hf-2 well and use Techlog software. The results from the obtained equations in comparison with those results of Green Castagna equation and measured data of dipole shear sonic imager of shear velocity for Mishrif, Rumiala and Mauddud formations. It is found from the comparison that the result is consistent each other’s. The consistent reflect the reality of shear waves values obtained in these formations. The comparison in Ahmadi formation also shows a consistent result for the obtained equations but it shows some differences from the dipole shear sonic imager and shear velocity reference values. The authors believed that the difference in some values of the Ahmadi Formation may be due to the high shale volume in comparison to the other formations.
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Al-Banna, Ahmed, Hayder Majeed, Salar Al- Karadagh, and Salah Shalash. "Construction of Regional Seismic Section Along Central Part of Iraq and its Geological Importance." Iraqi Geological Journal 57, no. 1B (February 29, 2024): 40–54. http://dx.doi.org/10.46717/igj.57.1b.4ms-2024-2-13.
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A regional seismic section was constructed from fourteen local seismic lines from different surveys crossing the central part of Iraq from west to east. The seismic lines’ surveys were performed during the period 1974–1990. The length of the regional seismic section is 662.5 km. The considered seismic lines are unified to the sea level datum. The quality of seismic lines is relatively poor in the western part of the regional seismic section, but it is of good quality in the central and eastern parts. Seven reflectors were identified along the regional seismic section, corresponding to ages from the Ordovician to the Miocene. The formations are Khabour (Mid-Ordovician), Akkas (Upper Silurian), Kurra Chine (Upper Triassic), Najmah (Upper Jurassic), Mauddud (Mid-Cretaceous), Shiranish (Upper Cretaceous) and Fatha (Lower Fars) (Mid-Miocene). The Two-way times for these seismic reflectors from the west to the east are 1691 – 4000 ms, 750-4000 ms, 0-4000 ms, 208-4000 ms, 206 -3310 ms, 205 -2700 ms, and 216-2500 ms for the seven formations; starting from the oldest formation (Khabour Formation to the youngest one (Fath Formation ), respectively. The top depth values of the considered formations were defined from west to east for each formation (0-4.189) km, (0.456-4.880) km, (0.708-5.936) km, (0.802-8.5) km, (0-8.977) km, (0.5-9) km, and (1.8-9) km from the oldest to the youngest formation, respectively. The horizon generally dips towards the east. Two sedimentary basins were identified, the first in the western part of Iraq within the Paleozoic formation, while the eastern basin was within the Cenozoic and Mesozoic formations. These two basins are separated by an uplift at the central part of the regional seismic section. This uplift region was confirmed by gravity and magnetic high anomaly. Many faults were detected along the regional seismic profile. Most of these faults extend from the deeper to the shallower formations.
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Bracken, Kyle. "Mechanical stratigraphy and layer-bound normal faulting in the Upper Cretaceous Niobrara Formation, Wattenberg Field, Colorado." Mountain Geologist 57, no. 2 (April 1, 2020): 67–93. http://dx.doi.org/10.31582/rmag.mg.57.2.67.
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Layer-bound normal faults are pervasive within the very fine-grained rocks of the Upper Cretaceous Niobrara and Carlile formations in the Denver Basin. 3-D seismic and well log interpretation reveal a complex, segmented fault system that is divided into two discrete tiers: an upper tier located in the Pierre Shale, and a lower tier located in the Niobrara Formation. 3-D fault throw analysis shows maximum throw near the top of the Niobrara Formation with steep, asymmetrical throw gradient down section in the lower Niobrara and Carlile formations. Faults are laterally well-connected in the upper Niobrara Formation and commonly form linear arrays of linked graben systems. In contrast, faults deeper in the stratigraphic section that offset the Carlile and Greenhorn formations are more segmented and commonly form half grabens (as opposed to full, fault-bound grabens). In cross-section, fault planes measured from seismic have a general dip of 45°. However, close inspection reveals that faults consistently change dip angle as they pass through the lower Niobrara Formation, refracting from ~55° to ~35° through the Niobrara C Marl, then back up to ~50° in the Carlile and Greenhorn formations. The fault dip refraction produces a contractional step or bend in the fault plane associated with the lower dip segments. This geometry is investigated further with horizontal image logs and other borehole data to reveal a kinematic relationship between fault dip angle and mechanical stratigraphy. Field examples of normal faults that cut mechanically layered rock help better understand these complex fault geometries and provide reasonable inferences to their development and propagation history. In summary, it is argued that the mechanically layered nature of the Niobrara and Carlile formations is responsible for many of the fault characteristics described and provides valuable insight into understanding the fault system
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Sztanó, Orsolya, Michal Kováč, Imre Magyar, Michal Šujan, László Fodor, András Uhrin, Samuel Rybár, Gábor Csillag, and Lilla Tőkés. "Late Miocene sedimentary record of the Danube/Kisalföld Basin: interregional correlation of depositional systems, stratigraphy and structural evolution." Geologica Carpathica 67, no. 6 (December 1, 2016): 525–42. http://dx.doi.org/10.1515/geoca-2016-0033.
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AbstractThe Danube / Kisalföld Basin is the north-western sub-basin of the Pannonian Basin System. The lithostratigraphic subdivision of the several-km-thick Upper Miocene to Pliocene sedimentary succession related to Lake Pannon has been developed independently in Slovakia and Hungary. A study of the sedimentary formations across the entire basin led us to claim that these formations are identical or similar between the two basin parts to such an extent that their correlation is indeed a matter of nomenclature only. Nemčiňany corresponds to the Kálla Formation, representing locally derived coarse clastics along the basin margins (11- 9.5 Ma). The deep lacustrine sediments are collectively designated the Ivanka Formation in Slovakia, while in Hungary they are subdivided into Szák (fine-grained transgressive deposits above basement highs, 10.5 - 8.9 Ma), Endrőd (deep lacustrine marls, 11.6 -10 Ma), Szolnok (turbidites, 10.5 - 9.2 Ma) and Algyő Formations (fine-grained slope deposits, 10 - 9 Ma). The Beladice Formation represents shallow lacustrine deltaic deposits, fully corresponding to Újfalu (10.5 - 8.7 Ma). The overlying fluvial deposits are the Volkovce and Zagyva Formations (10 - 6 Ma). The synoptic description and characterization of these sediments offer a basin-wide insight into the development of the basin during the Late Miocene. The turbidite systems, the slope, the overlying deltaic and fluvial systems are all genetically related and are coeval at any time slice after the regression of Lake Pannon initiated about 10 Ma ago. All these formations get younger towards the S, SE as the progradation of the shelf-slope went on. The basin got filled up to lake level by 8.7 Ma, since then fluvial deposition dominated.
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Cooper, D. J. W. "Hamrat Duru Group: revised stratigraphy of a Mesozoic deep-water passive margin in the Oman Mountains." Geological Magazine 124, no. 2 (March 1987): 157–64. http://dx.doi.org/10.1017/s0016756800015971.
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AbstractThe stratigraphy of the Hawasina Complex is redefined and rationalized to conform with standard stratigraphical nomenclature. Previously proposed tectono-stratigraphical units are abandoned in favour of a system that relies on the lateral correlation of lithofacies between structural units. To this end, the Dibba, Dhera, Wahrah and Al Ayn Formations are incorporated into an expanded Hamrat Duru Group. This group is divided into five formations, the Zulla, Guweyza Sandstone, Guweyza Limestone, Sid'r and Nayid and spans Triassic to Mid Cretaceous (Cenomanian) time. It locally passes up into the syn-orogenic sediments of the Riyamah Member of the Muti Formation. The nomenclature of the deeper-water, chert-dominated formations is left unaltered.
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van Niekerk, H. S., and N. J. Beukes. "Revised definition/outline of the Kheis Terrane along the western margin of the Kaapvaal Craton and lithostratigraphy of the newly proposed Keis Supergroup." South African Journal of Geology 122, no. 2 (June 1, 2019): 187–220. http://dx.doi.org/10.25131/sajg.122.0014.
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Abstract The Kheis Province is situated between the Namaqua-Natal Province and the western margin of the Kaapvaal Craton in the Northern Cape Province of South Africa. It has been described as a thin-skinned fold and thrust belt formed between 1800 and 1700 Ma. The lithostratigraphic subdivision of the rock units comprising the Kheis Province has been a source of much controversy. From detailed study of aerial photography and satellite imagery, as well as field-based studies, the outcrop patterns in the Kheis Province and Kaaien Terrane were reinterpreted and a new stratigraphic subdivision is outlined here. It is proposed that the structural Kaaien Terrane and Kheis Province should be combined into the Kheis Terrane and that the rocks occurring in the Kheis Terrane should be grouped together to form the new Keis supergroup, with the basal metaconglomerate of the Mapedi/Gamagara Formation recognised as the regional unconformity between the Keis supergroup and the underlying rocks of the Transvaal Supergroup in the Griqualand West area. The Keis supergroup is subdivided from the base upwards into the Elim-, Olifantshoek-, Groblershoop- and Wilgenhoutsdrif groups. The basal Elim group is composed of the Mapedi/Gamagara- and Lucknow formations. It is overlain with a regional erosional unconformity by the Olifantshoek group, which is made up of the Neylan-, Hartley-, Volop- and Top Dog formations. The Olifantshoek group is conformably overlain by the Groblershoop group which is comprised of three upward coarsening successions:the Faanshoek- and Faansgeluk formations,the Maraisdraai- and Vuilnek formations andthe Opwag- and Skurweberg formations. The Groblershoop group is in turn erosively overlain by the rocks of the Wilgenhoutsdrif Group, which include the basal erosive Groot Drink formation which is overlain by the Zonderhuis- and Leerkrans formations. The lithologies of the Keis supergroup are in faulted contact with the rocks of the younger Areachap Group of the ~1200 Ma Namaqua-Natal Metamorphic Province.
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Armstrong, KN, and SD Anstee. "The ghost bat in the Pilbara: 100 years on." Australian Mammalogy 22, no. 2 (2000): 93. http://dx.doi.org/10.1071/am00093.
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This paper summarises the roost habitat and distribution of the ghost bat, Macroderma gigas (Dobson, 1880), in the Pilbara region of Western Australia, with particular emphasis on natural habitats. The preferred habitat of M. gigas in the Hamersley Ranges appears to be caves beneath bluffs of low rounded hills composed of Marra Mamba geology. Habitats were also found in the larger hills of Brockman Iron Formation in the Hamersley Range, and other formations beneath bluffs composed of Gorge Creek Group geology to the north east. Granite rockpiles are also used in the eastern Pilbara. A summary of Pilbara records from numerous sources is presented, including anecdotal accounts and other new records. This includes a newly discovered maternity site from the Hamersley Ranges, only the third reported from natural cave formations in the region. Threats to M. gigas in the region are highlighted and include disturbances associated with mining and entanglement in barbed wire fences.
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Ghafur, Ala, Varoujan Sissakian, Diyar Khalil, and Sarhang Omer. "Suitability of the Carbonate Successions for Different Industrial Uses, Pira Magroon Anticline, Northern Part of Iraq, Kurdistan Region." Iraqi Geological Journal 55, no. 1C (March 31, 2022): 1–11. http://dx.doi.org/10.46717/igj.55.1c.1ms-2022-03-20.
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Many geological formations are exposed in the Pira Magroon anticline (Mountain); in the northeastern part of the Kurdistan Region, Iraq. The components of the exposed formations are carbonate rocks, especially limestone, which might be utilized for different industrial uses. To have an industrial assessment for the exposed limestone beds in the Pira Magroon anticline, Zewe Gorge has been chosen for sampling, where the Shiranish and Kometan formations are exposed in the outlet of the gorge. Eleven samples have been collected within the Shiranish and Kometan Formations starting from the bottom of the Kometan Formation, with different sampling intervals. Thereafter, the samples were prepared to be tested by XRF machine; in order to show the concentrations of the main oxides in the collected samples. The weighted averages were calculated from the concentrations of the oxides, and then the averages were indicated. Accordingly, the data was compared with the Iraqi and other industrial standards, to know the usage of the tested rocks for different industries. The acquired data showed that the carbonate successions of the Kometan and Shiranish Formations of the Zewe Gorge in the Pira Magroon Anticline, can be used in cement production.
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Tareq, Hiba. "Lithological Study of Mishrif, Rumaila, Ahmadi and Mauddud Formations Using Vp/ Vs Ratio, Acoustic Impedance and Well Logging at Amara Oil Field, Southern Iraq." Iraqi Geological Journal 54, no. 2D (October 31, 2021): 39–58. http://dx.doi.org/10.46717/igj.54.2d.4ms-2021-10-23.
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The lithology of four formations from the Cretaceous period (Mishrif, Rumaila, Ahmadi, and Mauddud) was evaluated using the Acoustic Impedance and Vp/Vs ratio cross plot from Rock Physics Templates. Dipole sonic logs in Am-6-Am-10 well log were used to calculate compression velocity then the estimated shear velocity using Greenberg Castagna equations. RHOB and VP logs were used to calculate Acoustic Impedance. The ratio of Vp/Vs was measured then used with Acoustic Impedance colored by shale volume which is measured from gamma ray log, porosity and water saturation to estimate lithology type of the considered formations using cross plots and rock physics chart in the Techlog software. The lithology of the formations found to be of high porosity limestone alternating with hard limestone layers and the shale volume increases in the Ahmadi formation. The water bearing zone was found in all Formations, this zone is indicted by high Vp/ Vs ratio and low AI. The hydrocarbon bearing zones were indicated by low amount of both Acoustic Impedance and Vp/Vs ratio and this observation was shown in Mishrif and Mauddud formations.
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Hussain, Sayed Mushahid, Syed Khaliq Hussain, and Enayatollah Emami Meybodi. "PETROGRAPHIC AND PROVENANCE OF THE SANDSTONE OF RAWALPINDI GROUP IN LESSER HIMALAYAS." Earth Science Malaysia 5, no. 2 (December 29, 2020): 93–103. http://dx.doi.org/10.26480/esmy.02.2021.93.103.
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In the present work, we deal with the petrographic and provenance of the sandstone of the Rawalpindi group in the lesser Himalayas. The formations present in the project area are Murree and Kamlial Formations of the Rawalpindi group. The petrological studies of Murree and Kamlial Formations determine the minerals composition prospect, which minerals have high proportion and which one is less proportion. Which aim to determine the petrological characteristic of these rock formations for the use of scientific studies or in engineering projects. Both of these two formations are Siwalik molasse deposits, the same orogeny correlation, same age from the same group. Determine the difference in such kind of similar rock formations are very important and also challenge in the field of geology. With highly advance petrographically analysis, it shows that Kamlial formation consists of heavy minerals such as garnet, tourmaline, etc., as compared with Murree formation consists of light minerals such as quartzite, Felice and feldspar, etc. And the provenance analysis of the sandstone of the Rawalpindi group is performed by the QFL ternary diagrams method. All the plots in the QFL diagram plot on recycled orogeny provenance field.
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Lazim, Aymen, Huda F. Khazaal, and Madhi A. R. Swadi. "Characterization of Structural Geology of Faihaa Oilfield, Southern Iraq." Journal of Petroleum Research and Studies 12, no. 3 (September 11, 2022): 1–20. http://dx.doi.org/10.52716/jprs.v12i3.546.
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Faihaa Oilfield is a new exploration Iraqi Oilfield located in southern Iraq and within Mesopotamian Plain, including the Block 9 exploration area, along the Iraqi-Iranian border. The study area included Faihaa Oilfield (in Iraq) and Yadavaran Oilfield (in Iran). They belong to one anticline (Dome) structure separated by the Iraqi-Iranian border, without a geological boundary between the fields. The current study aims to achieve structural geology analysis to the study area (Faihaa/Yadavaran structure). The structural analysis included geometric and genetic analyses of the study area. According to geometric and genetic analyses results, the Faihaa/Yadavaran structure is classified as an anticline, gentle, upright, non-plunge, and asymmetrical. According to thickness variation, there are two types of formations’ folds are recognized, Thickened and Supratenuous fold generated by two folding mechanisms bending and buckle mechanisms. Bending form Supratenuous fold, perhaps due to the vertical uplift of salt structure and/or basement faults, while buckle produces Thickened fold because of the parallel tectonic movement causes collision between Arabian Plate and Eurasian Plate. Consequently, a special strain pattern was formed and the reservoir quality in the crest of Mishrif and Yamama Formations was the best. The fold axis of the Faihaa/Yadavaran structure has a Boomerang shape, whereas it is almost straight from south to the center of the structure, then tends to the NW with different deviations over the study area formations. This direction may be due to the anticlockwise rotation of the Arabian Plate motion. The results of geometric and genetic analyses revealed that may be Faihaa/Yadavaran structure is one structural trap formed by tectonic activities; Hormuz salt structures, reactivated Basement faults, and Collision between Arabian and Eurasian Plates. The intensity of the tectonic activities of the study area maybe be less than surrounding Oilfields, therefore, the Faihaa Oilfield formation's depth was deeper than adjacent Oilfields.
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Wang, Jialin, Chaodong Wu, Zhuang Li, Tianqi Zhou, Yanxi Zhou, Geng Feng, and Yue Jiao. "The Pennsylvanian Composite Volcanism in the Bogda Mountains, NW China: Evidence for Postcollisional Rift Basins." Lithosphere 2020, no. 1 (October 6, 2020): 1–22. http://dx.doi.org/10.2113/2020/8852440.
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Abstract In this paper, we present new petrological, zircon U–Pb–Hf isotopic, bulk-rock geochemical, and Sr–Nd isotopic data for the rocks from the Pennsylvanian Liushugou and Qijiagou Formations, Bogda Mountains (BMs), northwest China. The new data help in understanding the petrogenesis and geodynamic background of the two formations, further constraining the evolution of BMs during the Pennsylvanian. The eastern Liushugou Formation is composed mainly of bimodal volcanic rocks, while the western Liushugou Formation is dominated by pillow basalts with interstitial limestones, peperites, and pyroclastic rocks. The Qijiagou Formation consists principally of bioclastic limestones, peperites, and volcanic and volcaniclastic rocks with turbidites. Depositional environment analyses of the Liushugou and Qijiagou Formations reveal subaqueous volcanism and a progressively deepening shallow marine environment with times. Zircon LA-ICP-MS U–Pb dating of felsic volcanic rocks from the Liushugou Formation indicates that the subaqueous volcanism occurred at ca. 310–302 Ma, viz., the Pennsylvanian era. The basaltic rocks from the Liushugou and Qijiagou Formations are high-K calc-alkaline, enriched in light rare earth elements and large-ion lithophile elements, and depleted in high-field-strength elements (Nb, Ta, and Ti). The above characteristics, together with their depleted isotopic signature (εNdt=3.0-8.1, εHft=8.0-15.6, and ISr=0.703-0.707), suggest the derivation from a depleted mantle source metasomatized by slab-derived fluids and sediment-derived melts. Most felsic volcanic rocks of the high-K calc-alkaline to shoshonite series from the Liushugou and Qijiagou Formations show features of the A2-type granites and have similar trace and isotopic composition to the basaltic rocks, which were probably generated from the partial melting of juvenile continental crust. Combining the newly acquired data with the regional geology, we propose that the Pennsylvanian volcanic and sedimentary rocks in the BMs were formed in a series of postcollisional rift basins which were related to local strike-slip faulting. Moreover, the volcanic rocks in the east were derived from a relatively deeper mantle source (thick lithosphere) due to their smaller rifting.
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Martínek, Karel, Jiří Pešek, and Stanislav Opluštil. "Significant hiatuses in the terrestrial Late Variscan Central and Western Bohemian basins (Late Pennsylvanian–Early Cisuralian) and their possible tectonic and climatic links." Geologica Carpathica 68, no. 3 (June 1, 2017): 269–81. http://dx.doi.org/10.1515/geoca-2017-0019.
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Abstract Significant changes in the stratigraphy of the Central and Western Bohemian Upper Palaeozoic basins occur during or shortly after hiatuses. The different extent and changes in the depocentres of the Radnice and Nýřany members (Moscovian) in the Plzeň Basin clearly indicate changes in the structure of this basin taking place during a break in sedimentation between these two units (311.9–308.3 Ma). Thick weathered rocks that occur in boreholes in the Mšeno–Roudnice Basin indicate another sedimentation break (305.9–304.1 Ma) between the Nýřany Member and the Týnec Formation (Kasimovian). Another possible hitherto undiscovered hiatus occurred between the Týnec and Slaný formations (Kasimovian–Gzhelian, about 304–303 Ma). The most significant changes in the configuration of the basins occurred between the Slaný and Líně formations (Gzhelian–Asselian, 301.6–300.6 Ma). This is indicated by deeply cut river valleys at the top of the Slaný Formation, by high thickness of weathered deposits occurring immediately beneath the Líně Formation, and mainly by the shift of depocentres from the southern to the northern part of the Central Bohemian basins. The hiatuses between the Radnice and Nýřany members and between the Slaný and Líně formations are accompanied by significant changes in the depocentres, and they are therefore interpreted primarily as tectonic events related to the extensional collapse of the Variscan orogenic belt. By contrast, the hiatuses beneath and above the Týnec Formation are interpreted as being the products of lower sedimentation rates during drier climates, which is consistent with the characteristics of the sediments, correlation with other Central European basins, and with climate models for this period. Due to the characteristics of the Líně Formation, in which the effects of climate aridization are clearly seen, the authors presume that tectonic as well as climatic changes occurred at the hiatus between the Slaný and Líně formations.
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Leather, David. "A new geological map and review of the Middle Devonian rocks of Westray and Papa Westray, Orkney, Scotland." Scottish Journal of Geology 57, no. 2 (April 19, 2021): sjg2020–030. http://dx.doi.org/10.1144/sjg2020-030.
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The Middle Devonian lacustrine sediments of Orkney, off the NE Scottish mainland, are composed largely of the Lower and Upper Stromness formations and overlying Rousay Formation. These three formations have been subdivided and defined by vertebrate biostratigraphic biozones with recent division of the Rousay Formation into three further units based on characteristic fish fossils. The division of the Rousay Formation has enabled a map to be constructed of the solid geology of the island of Westray, Orkney, based on fish identification, detailed logging of sedimentary cycles throughout the Rousay succession, parameters of divisional boundaries, and a survey of faults marking sinistral transtensional movement parallel to the Great Glen Fault. Post-Carboniferous shortening and basin inversion led to uplift, folding and reactivation of normal faults as reverse faults, to form a positive strike-slip flower structure in Westray. A suite of Permian igneous dykes intruded across Orkney include three minor offshoots in Westray. The resulting map is the first to make use of biostratigraphic units within the Rousay Flagstone, which are now regarded as Members.
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Tretyakova, O. G., and N. M. Tretyakova. "NEFU training geological polygons as unique sites for forming general professional competencies in the field of geology, prospecting and exploration of solid minerals." Vestnik of North-Eastern Federal University Series "Earth Sciences", no. 4 (December 19, 2023): 33–41. http://dx.doi.org/10.25587/2587-8751-2023-4-33-41.
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In the modern world; geology is one of the most important scientific disciplines that can provide key knowledge about the structure and processes of our planet. Applied geology; in particular; requires high qualifications and practical experience; and field training geological practices play a key role in the formation of not only theoretical knowledge of students but also of their practical skills. Educational geological practices permit students of the Faculty of Geology and Survey; North-Eastern Federal University; to master basic methods in field geological research; including the analysis of rock formations; the identification of geological boundaries; and the recognizing of relief-faults.This article provides an overview of the structure and specifics of field training geological practices; involving multiple stages from preparatory to fieldwork period. The article considers not only essence and significance of field research in terms of formation practical geological skills but also analyze the key aspects that make these practices an integral part of the education of future geologists.
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Vallée, Marc A., Richard S. Smith, and Pierre Keating. "Case history of combined airborne time-domain electromagnetics and power-line field survey in Chibougamau, Canada." GEOPHYSICS 75, no. 2 (March 2010): B67—B72. http://dx.doi.org/10.1190/1.3343573.
Full textAbstract:
Exploration for volcanogenic massive sulfides requires good geologic understanding. Geologic knowledge often is limited by a lack of outcrops. This is especially true in Canada under residual glacial covers. Geologic information must therefore be complemented by information obtained using means such as geophysical and geochemical observations. Electromagnetic (EM) methods extend lithological understanding to depths beyond the overburden. Massive sulfides are highly conductive and, depending on their depth and volume, may be detected easily by airborne EM surveys. They are more often equant than graphitic sediments, which typically have longer strike length. Current EMtechniques that identify massive sulfides operate in the frequency or time domain, the latter being more common. Additional information can be provided by using power-line fields as a source of EM signals when the powerlines are appropriately located in the area of interest. We have worked in an active exploration area near Chibougamau, Canada, known for a large occurrence of massive sulfide deposits. The geology is a sequence of volcanic formations with felsic and mafic intrusions. Our magnetic technique responded well to mafic rocks. An airborne time-domain EM survey mapped localized and intrasedimentary conductors in that area. We learned in our study that power-line EM fields can be used to map large-extent conductive formations and narrow geologic faults.
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Nair, Kajal, John Singleton, Christopher Holm-Denoma, and Sven Egenhoff. "Detrital Zircon Geochronology of Pennsylvanian-Permian Strata in Colorado: Evidence for Appalachian-Derived Sediment and Implications for the Timing of Ancestral Rocky Mountains Uplift." Mountain Geologist 55, no. 3 (July 2018): 119–40. http://dx.doi.org/10.31582/rmag.mg.55.3.119.
Full textAbstract:
Pennsylvanian-Permian time in north-central Colorado corresponds with uplift of the Ancestral Front Range and deposition of the Fountain, Ingleside, and Lyons Formations along its flanks. In southwestern Colorado, deposition of the Molas and Hermosa Formations along the flanks of the Uncompahgre Highlands largely represents Pennsylvanian time. We present new detrital zircon U-Pb geochronology data for the Ingleside and Lyons Formations in north-central Colorado and the Molas and Hermosa Formations in southwestern Colorado to understand sediment provenance and dispersal patterns. We determined U-Pb ages using LA-ICPMS on 120-150 zircon grains from five sandstone samples collected from shallow marine and eolian facies within the Ingleside, Lyons, Molas, and Hermosa Formations. All sandstone samples display a mixed Laurentian derivation, with age populations that record local and distal sediment sources. All samples also contain between 5% and 10% concordant Paleozoic-age zircon grains ranging from 330–490 Ma, coinciding with high magmatic flux during the Taconic and Acadian orogenies in the Appalachian orogen. Ultimate derivation from the Appalachians are also interpreted for zircon age populations ranging from 500-750 Ma and 1000-1300 Ma that likely originated from Pan-African and Grenville terranes respectively. This study detects the earliest documented appearance of Paleozoic zircons along the northern Ancestral Front Range, corresponding to deposition of the lower Ingleside Formation. We compare our data along the Front Range to previous detrital zircon studies from the underlying Fountain Formation to conclude that the Fountain-Ingleside transition was accompanied by a decrease in locally sourced detrital zircons, most likely marking the cessation of Ancestral Front Range uplift. Conversely, deposition across the Molas-Hermosa contact in southwestern Colorado was accompanied by an increase in locally-sourced detrital zircon grains, most likely marking the initiation of the Uncompahgre uplift.
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Çakir, Üner, and Tijen Üner. "The Ankara Mélange: an indicator of Tethyan evolution of Anatolia." Geologica Carpathica 67, no. 4 (August 1, 2016): 403–14. http://dx.doi.org/10.1515/geoca-2016-0025.
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Abstract The Ankara Mélange is a complex formed by imbricated slices of limestone block mélanges (Karakaya and Hisarlıkaya Formations), Neotethyan ophiolites (Eldivan, Ahlat and Edige ophiolites), post-ophiolitic cover units (Mart and Kavak formations) and Tectonic Mélange Unit (Hisarköy Formation or Dereköy Mélange). The Karakaya and Hisarlıkaya formations are roughly similar and consist mainly of limestone block mélange. Nevertheless, they represent some important geological differences indicating different geological evolution. Consequently, the Karakaya and Hisarlıkaya formations are interpreted as Eurasian and Gondwanian marginal units formed by fragmentation of the Gondwanian carbonate platform during the continental rifting of the Neotethys in the Middle Triassic time. During the latest Triassic, Neotethyan lithosphere began to subduct beneath the Eurasian continent and caused intense deformation of the marginal units. The Eldivan, Ahlat and Edige ophiolites represent different fragments of the Neotethyan oceanic lithosphere emplaced onto the Gondwanian margin during the Albian–Aptian, middle Turonian and middle Campanian, respectively. The Eldivan Ophiolite is a NE–SW trending and a nearly complete assemblage composed, from bottom to top, of a volcanic-sedimentary unit, a metamorphic unit, peridotite tectonites, cumulates and sheeted dykes. The Eldivan Ophiolite is unconformably covered by Cenomanian–Lower Turonian sedimentary unit. The Eldivan Ophiolite is overthrust by the Ahlat Ophiolite in the north and Edige Ophiolite in the west. The Ahlat ophiolite is an east–west oriented assemblage comprised of volcanic-sedimentary unit, metamorphic unit, peridotite tectonites and cumulates. The Edige Ophiolite consists of a volcanic-sedimentary unit, peridotite tectonites, dunite, wherlite, pyroxenite and gabbro cumulates. The Tectonic Mélange Unit is a chaotic formation of various blocks derived from ophiolites, from the Karakaya and Hisarlıkaya formations and from post-ophiolitic sedimentary units. It was formed during the collision between Anatolian Promontory and Eurasian Continent in the middle Campanian time.
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Kennedy, W. J., and W. K. Christensen. "Coniacian and Santonian ammonites from Bornholm, Denmark." Bulletin of the Geological Society of Denmark 38 (February 19, 1991): 203–26. http://dx.doi.org/10.37570/bgsd-1990-38-19.
Full textAbstract:
The ammonite faunas from the Amager Limestone and Bavnodde Greensand Formations of the island of Bornholm, Denmark are described. The Amager Limestone at its type locality has yielded five species, including the age diagnostic Scaphites (Scaphites) kieslingswaldensis kieslingswaldensis · Langenhan & Grundey, 1891 and Peroniceras tridorsatum (Schliiter, 1867). The Bavnodde Greensand has yielded seven species, including Scaphites (Scaphites) kieslingswaldensis fischer Riede!, 1931, which firs! appears in the Lower Santonian elsewhere in Europe. The age of the two formations is discussed. The Amager Limestone Formation is in part at least Middle Coniacian on ammonite evidence, Lower Coniacian on inoceramid bivalve evidence, while foraminifera suggest thai the formation spans most of the Coniacian. Tue Bavnodde Greensand Formation is referable to the upper Coniacian-Lower Santonian on the basis of ammonites, belemnites, and inoceramid bivalves.
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Waterhouse, J. B. "Stratigraphy and age of the ammonoid Durvilleoceras woodmani from the Greville Subgroup, New Zealand." Geological Magazine 124, no. 6 (November 1987): 527–42. http://dx.doi.org/10.1017/s0016756800017362.
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AbstractDurvilleoceras woodmani of debated Late Permian or Early Triassic age is accompanied by other ammonoids, deemed to belong to Araxoceratidae, Xenodiscidae, and Goniatitida, of chiefly Late Permian age. The ammonoids are found principally in the Deserter Bay and especially Tongue Point Members (new names) of the newly named South Arm and Wells Arm formations of the Greville Subgroup, which are overlain, apparently in normal stratigraphic succession, by the Waiua Formation and newly named formations of the Te Mokai Group, with three successive faunas of Permian appearance.
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Cooper, A. H., A. W. A. Rushton, S. G. Molyneux, R. A. Hughes, R. M. Moore, and B. C. Webb. "The stratigraphy, correlation, provenance and palaeogeography of the Skiddaw Group (Ordovician) in the English Lake District." Geological Magazine 132, no. 2 (March 1995): 185–211. http://dx.doi.org/10.1017/s0016756800011742.
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AbstractA new lithostratigraphy is presented for the Skiddaw Group (lower Ordovician) of the English Lake District. Two stratigraphical belts are described. Five formations are defined in the Northern Fells Belt, ranging in age from Tremadoc to early Llanvirn. They are all mudstone or sandstone dominated, of turbidite origin; in ascending order they are named the Bitter Beck, Watch Hill, Hope Beck, Loweswater and Kirk Stile formations. Two formations are defined in the Central Fells Belt, ranging in age from late Arenig to Llanvirn. These are the Buttermere Formation – a major olistostrome deposit – overlain by the Tarn Moor Formation, consisting of turbidite mudstones with volcaniclastic turbidite sandstone beds. A revised graptolite and new acritarch biostratigraphy for the Skiddaw Group is presented with eight graptolite biozones and thirteen acritarch assemblages and sub-assemblages. The provenance of the group is assessed from detailed petrographical and geochemical work. This suggests derivation, in the early Ordovician, largely from an old inactive continental arc terrane lying to the southeast, with the appearance of juvenile volcanic material in the Llanvirn. Comparisons and correlations of the Skiddaw Group are made with the Isle of Man and eastern Ireland.
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Musu, Junita Trivianty, Bambang Widarsono, Andi Ruswandi, Himawan Sutanto, and Purba Humbang. "DETERMINATION OF SHALE GAS POTENTIAL OF NORTH SUMATRA BASIN: AN INTEGRATION OF GEOLOGY, GEOCHEMISTRY, PETROPHYSICS AND GEOPHYSICS ANALYSIS." Scientific Contributions Oil and Gas 38, no. 3 (December 30, 2015): 193–212. http://dx.doi.org/10.29017/scog.38.3.548.
Full textAbstract:
A detailed combined geological and geophysical study in North Sumatra basin has shown that prospective formations for shale play containing gas sweet spots are found to be in shales from Bampo, Belumai, and Baong Formations. Bampo Formation exhibits low shale gas potential with very low to medium in organic material contents, maturity index of immature to mature, and moderate brittleness. Rocks within the formation tend to be reactive to highly reactive to water, with a moderate degree of swelling capacity. Porosity varies within 5.8 - 7.4 % with permeability ranging from 0.37 to 3.2 mD. Sweet spots in the formation found around Basilam-1 and Securai-1wells occupy about 21% of the formation. On the other hand, Belumai Formation shows moderate to good shale gas potential, with low to high organic material contents, immature to mature levels of maturity, and moderately brittle to brittle. Sweet spot areas in the formation found around the two wells are about 29% of the formation. For Baong Formation, analysis reveals moderate to good shale gas potential, with low to medium contents of organic material, immature to mature in maturity index, moderately brittle to brittle in brittleness, and tendency of being reactive to highly reactive to water but with low degree of swelling capacity. Sweet spots in the formation found around the two wells occupies are roughly 11% of the total formation volume in the area. Basin modeling leading to gas resources estimation for Baong, Belumai and Bampo Formations has led to estimated volumes of 6,379 TCF, 16,994 TCF, and 25,024 TCF, respectively, with a total amount of 48,397 TCF. The resources figures are speculative in nature and do not incorporate any certainty and efficiency factors.
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Zagorovsky, Yuri A. "The North Tambey uplift history study using 3D seismic data." Georesursy 24, no. 2 (September 30, 2022): 69–76. http://dx.doi.org/10.18599/grs.2022.3.5.
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Paper shows the information about the geological and geophysical exploration of Tambeyskoye natural gas field located in the north of the Yamal Peninsula. The problems with mapping of natural gas deposits in Cretaceous and Jurassic formations are described. The results of formation thickness analysis are presented in order to explain the reasons for the unprecedented concentration of separate natural gas accumulations and the heterogeneous saturation of massive reservoirs in Cretaceous formations. The method of paleotectonic analysis is briefly described, the initial data are reported. Structural and isopach maps are presented. Structural elements and their evolution in Jurassic and Cretaceous time are presented. It was concluded that different structural elements of the work area transformed quite independently until the end of Cenomanian. The modern shape of North Tambey uplift was forming during the Neogene to Quarter age. Natural gas bearing reservoirs in Jurassic formation with the overpressure were reported. The young age of the North Tambey uplift, the unprecedented concentration of separate natural gas accumulations, the and the heterogeneous saturation of massive reservoirs in Cretaceous formations, overpressure in Jurassic formation – all these facts show that the Tambeyskoye natural gas field is under active gas accumulation. Hydrocarbon gases coming from deep Jurassic formations and it was not enough time for gas accumulations to be distributed over the reservoirs of Cretaceous.
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Krivolutskaya, Nadezhda, Valery Mikhailov, Bronislav Gongalsky, Dmitry Kuzmin, and Natalia Svirskaya. "The Permian-Triassic Riftogen Rocks in the Norilsk Area (NW Siberian Province): Geochemistry and Their Possible Link with PGE-Cu-Ni Mineralization." Minerals 12, no. 10 (September 24, 2022): 1203. http://dx.doi.org/10.3390/min12101203.
Full textAbstract:
The volcanic rocks in the Vologochan syncline, the Khikey River valley, and Mount Sunduk, within the Norilsk area in the NW Siberian large igneous province, have been studied. They belong to the Ivakinsky, Syverminsky, Gudchikhinsky, Khakanchansky, Nadezhdinsky, Tuklonsky, and Morongovsky Formations. These Formations consist of trachybasalts, picritic basalts and tholeiitic basalts with aphyric and porphyritic textures, and intersertal and poikiloofitic structures. For the first time, we demonstrate the variations in the structure and composition of these Formations along the strike, based on 151 analyses of the major and trace elements in the rocks. The thickness of all the Formations, excepting the Morongovsky, reduce dramatically from the Yenisey–Khatanga trough to the Tunguska syneclise, and they pinch out in the east of the Norilsk area and are attributed to riftogen (rift) basalts. The rock compositions also change in this direction, especially in the Gudchikhinsky and Nadezhdinsky Formations. The two subformations of the Gudchikhinsky formation, the lower and upper, disappear in the east, so the Gudchikhinsky consists only of high-Mg rocks, picritic basalts, and picrites. The composition of the Nadezhdinsky formation varies intensely in its (Gd/Yb)n and (Th/Nb) ratios from the Vologochan syncline to the Khikey River valley. These structural and compositional variabilities differ between the rift formations and the platform ones. Two gabbro–dolerite sills from these areas that are close to the Norilsk and Ergalakh intrusive complexes have been studied. The metal contents in volcanic and intrusive rocks are similar and do not differ from the barren rocks of the South Pyasinsky massif comprising the PGE-Cu-Ni deposits. Only the Gudchikhinsky Formation contains elevated Cu and Ni concentrations. These features and the coinciding spatial distribution of the ore-bearing intrusions and picrites of the Gudchikhinsky rocks in the Norilsk–Igarka paleorift suggest their genetic link. It is proposed that the initial sulfides could have been formed in the mantle, as the Gudchikhinsky picrites, transported to the lower crust, and then involved by the trap magmas in the origin of the ore-bodies in the Norilsk deposits.
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Musu, Junita Trivianty, Bambang Widarsono, Andi Ruswandi, Himawan Sutanto, and Humbang Purba. "DETERMINATION OF SHALE GAS POTENTIAL OF NORTH SUMATRA BASIN: AN INTEGRATION OF GEOLOGY, GEOCHEMISTRY, PETROPHYSICS AND GEOPHYSICS ANALYSIS." Scientific Contributions Oil and Gas 38, no. 3 (December 1, 2015): 193–212. http://dx.doi.org/10.29017/scog.38.3.946.
Full textAbstract:
A detailed combined geological and geophysical study in North Sumatra basin has shown thatprospective formations for shale play containing gas sweet spots are found to be in shales from Bampo,Belumai, and Baong Formations. Bampo Formation exhibits low shale gas potential with very low tomedium in organic material contents, maturity index of immature to mature, and moderate brittleness. Rockswithin the formation tend to be reactive to highly reactive to water, with a moderate degree of swellingcapacity. Porosity varies within 5.8 - 7.4 % with permeability ranging from 0.37 to 3.2 mD. Sweet spots inthe formation found around Basilam-1 and Securai-1wells occupy about 21% of the formation. On the otherhand, Belumai Formation shows moderate to good shale gas potential, with low to high organic materialcontents, immature to mature levels of maturity, and moderately brittle to brittle. Sweet spot areas in theformation found around the two wells are about 29% of the formation. For Baong Formation, analysisreveals moderate to good shale gas potential, with low to medium contents of organic material, immatureto mature in maturity index, moderately brittle to brittle in brittleness, and tendency of being reactiveto highly reactive to water but with low degree of swelling capacity. Sweet spots in the formation foundaround the two wells occupies are roughly 11% of the total formation volume in the area. Basin modelingleading to gas resources estimation for Baong, Belumai and Bampo Formations has led to estimatedvolumes of 6,379 TCF, 16,994 TCF, and 25,024 TCF, respectively, with a total amount of 48,397 TCF.The resources figures are speculative in nature and do not incorporate any certainty and efficiency factors.
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Ali, Ali Hussein, Ayyed Hussein Ward, and Amera Ismael Hussain. "Tectonic Indications for Thickness Change of Geological Formations in South Eastern Part Area of Safen Anticline, North Eastern Iraq." Iraqi Geological Journal 55, no. 1D (April 30, 2022): 141–50. http://dx.doi.org/10.46717/igj.55.1d.10ms-2022-04-26.
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The study area is located in the southeastern part of Safen Anticline, northeastern Iraq. The aim of the study is to discuss the listric fault role in the change of the deposition basin topography of Bekhme and Shiranish formations and finally change of their thicknesses. The field data picked up in September of 2020 include bed attitudes and formation boundaries, with their positions. After the drawing of three cross sections and calculating the thickness of Bekhme and Shiranish formations in the studied area, the results showed that the thickness of the Bekhme Formation which represents the reef environment, increases in thickness within the northeastern limb of the fold, While the thickness of the Shiranish Formation which represents the deep environment, increases within the southwestern limb of the fold. These changes were concluded as result occurred due to the reverse movement of the Listeric fault responsible for the growth of the fold synchronously with Bekhme and Shiranish formation deposition.
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Al-Hadidy, Aboosh H. "Paleozoic stratigraphic lexicon and hydrocarbon habitat of Iraq." GeoArabia 12, no. 1 (January 1, 2007): 63–130. http://dx.doi.org/10.2113/geoarabia120163.
Full textAbstract:
ABSTRACT The crystalline Proterozoic Basement does not crop out in Iraq, but is interpreted from seismic and geophysical potential data to range in depth from about 6–10 km in western Iraq, to 12–15 km in the Zagros Mountains, in eastern Iraq. The Cambrian and Lower Ordovician sedimentary successions of Jordan and Saudi Arabia (including the Middle Cambrian Burj carbonates) are interpreted to extend into Iraq based on seismic data and regional correlations. The entire Paleozoic succssion is about 3–4 km thick. The Ordovician-Permian succession in Iraq consists of ten formations that are here described in a lexicon format. For each formation, the type and reference sections in outcrop or/and subsurface are reviewed (as defined by the original authors or herein), and further documented by including subsurface data (electrical logs and biostratigraphic studies). The Ordovician-Permian formations (and their members) are here placed chronostratigraphically according to the “Geological Time Scale GTS 2004” (and standard global Ordovician stages) and the Arabian Plate sequence stratigraphic framework. The ten formations are: (1) the Early?, Middle and Late Ordovician Khabour Formation (with from base-up seven informal members K7 to K1); (2) the Silurian Akkas Formation (with the proposed lower Hoseiba and upper Qaim members); (3 and 4) the Late Devonian Pirispiki Red Beds Formation and enclosed Chalki Volcanics; (5) the Late Devonian (Famennian) and early Carboniferous (early Tournaisian) Kaista Formation; (6) the Carboniferous (Tournaisian) Ora Formation; (7) the Carboniferous (Tournaisian-Visean) Harur Limestone Formation; (8) the Visean-Serpukhovian Raha Formation (proposed here); (9) the late Carboniferous-early Middle Permian Ga’ara Formation; and (10) the late Middle and Late Permian Chia Zairi Formation (in outcrop consisting from base-up of the informal Dariri, Satina Anhydrite and Zinnar members). The Late Devonian-early Carboniferous succession, comprising the Pirispiki, Chalki, Kaista, Ora, Harur and Raha formations, is here proposed to comprise the Khleisia Group. The Paleozoic succession of Iraq is hydrocarbon-prospective in the western part of the country, and particularly in the Western Desert near Jordan, Saudi Arabia and Syria. The source-rock component of the petroleum system consists of several potential organic-rich shales including the regionally widespread Silurian Akkas “hot shale”. In the Akkas-1 well, two hot shale units have a combined thickness of 61 m (210 ft) and total organic carbon (TOC) values that reach 16.6%. Several reservoirs and seals present exploration targets in the Western Desert of Iraq. In the Akkas field, light (specific gravity of 42° API), sweet oil and gas (no H2S) were discovered in 1993 in the Akkas and Khabour formations, respectively. The Akkas reservoir occurs in the upper Qaim Member of the Silurian Akkas Formation and consists of sandstones that have a porosity of 6.5% and permeability of 0.2 mD. The Khabour reservoir occurs in the Upper Ordovician K1–K4 members and consists of sandstones with a fracture porosity of up to 7.6% and permeability of 0.13 mD. In North Iraq the carbonates of the Permian Chia Zairi and Triassic Mirga Mir formations correlate to gas reservoirs in the Khuff Formation of Arabia and the Dalan and Kangan formations of Iran, and may therefore be prospective. Southern Iraq, along the Kuwait and Saudi Arabian border, may also be prospective; however, no wells have been drilled into the deep Paleozoic succession in this vast region.
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McMillan, A. A. "A provisional Quaternary and Neogene lithostratigraphical framework for Great Britain." Netherlands Journal of Geosciences 84, no. 2 (July 2005): 87–107. http://dx.doi.org/10.1017/s0016774600022988.
Full textAbstract:
AbstractThis paper presents an overview of a provisional lithostratigraphical framework for the Quaternary and Neogene deposits of Great Britain (England, Scotland and Wales) (onshore). The objective is to provide a workable framework to aid future Quaternary mapping and research, and a stratigraphical scheme capable of use in a wide variety of applications. Using the full hierarchy, a supergroup, group and subgroup lithostratigraphy, based upon the primary mapping unit, the formation, is proposed. It is recommended that some classes of lithogenetically-defined deposits which, at present cannot be accorded formational status, should be assigned informally to one of the proposed groups or subgroups. The framework distinguishes one superficial deposits supergroup within which seven groups are defined: i) Crag Group, marine deposits (Late Pliocene to Early Pleistocene); ii), Dunwich Group, fluvial deposits (pre-Anglian/pre-Elsterian); iii) Residual Deposits Group; iv) British Coastal Deposits Group, coastal and marine deposits (Anglian to Holocene); v) Britannia Catchments Group, fluvial, organic and mass movement deposits (Anglian to Holocene) within broadly defined catchment areas related to Late Devensian to present-day physiography; vi) Albion Glacigenic Group, glacigenic deposits (pre-Devensian/pre-Weichselian), and vii) Caledonia Glacigenic Group, glacigenic deposits (Devensian/Weichselian). North of the Devensian (Weichselian) ice-sheet limit, a series of glacigenic subgroups are defined geographically for the two glacigenic groups on the basis of mappable formations of till. The subgroups include associated formations of glaciofluvial and glaciolacustrine deposits. Consequently some of the glacigenic water-lain units may extend beyond the Devensian limit. Catchment subgroups of the Britannia Catchments Group are proposed for formations and lithogenetic units defined within broad present-day physiographic regions by major river drainage systems that have developed since Middle Pleistocene time. Lithostratigraphical description and correlation of formations will aid the refinement of the proposed framework and enable the development of lithostratigraphical maps and three-dimensional models. As well as offering a unified framework for onshore Quaternary and Neogene deposits the proposed supergroup, group and subgroup structure may prove useful for a wide range of regional applications (e.g. hydrological, hydrogeological, engineering).
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Chen, Ying Fu, Gen Hou Wang, and Xian Le Duan. "Zircon SHRIMP Geochronology and Geochemistry of late Jurassic Volcanic Rocks in Huiyin Obo Area, Inner Mongolia, China." Advanced Materials Research 634-638 (January 2013): 3527–36. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.3527.
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The primary object of this fundamental research is to reveal new study of Late Jurassic Manketou Obo Formation and Early Cretaceous Manitu Formation, Baiyingaolao Formation, in Huiyin Obo area, East Ujimqin County, Inner Mongolia. Several sets of experiments were carried out to test the validity of three formations’ age, and these forms can be contrasted with Chagannuoer Formation and Bulagehada Formation from “1/250000 Regional Geology Survey in Hesigewula Farm.” As a result of our study, we concluded that further research into the Mesozoic volcanic rocks on the Huiyin Obo is necessary.