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1
Gaudenji, Tivadar, e Mladjen Jovanovic. "Quaternary stratigraphy: Recent changes". Glasnik Srpskog geografskog drustva 92, n. 4 (2012): 1–16. http://dx.doi.org/10.2298/gsgd1204001g.
Testo completoAbstract (sommario):
Corrections to the Quaternary stratigraphic division of Serbia was updated/renewed by lowering limit of the Pleistocene / Quaternary to the beginning of the Gelasian that is at approximately 2.588 million years. Rather than the officially rejected Penck & Br?ckner Alpine stratigraphic model, the use of oxygen isotope stages (OIS / MIS) is recommended. Climatostratigraphic terms glacial and interglacial have a regional applicability and their use is recommended only in areas where there are traces of glaciation, while the terms cold and warm stage (or moderate) stages should be used within the global context. Eopleistocene is a regional term for the former Soviet Union and due to its uniqueness it can hardly be applied in the stratigraphical scheme of the Quaternary depostis in Serbia. With the latest extension of the Lower Pleistocene, further use of Eopleistocene would lead to further confusion in stratigraphic correlation as such the use of the Lower / Early Pleistocene or other appropriate stratigraphic units is recommended.
2
Krider, P. Reed. "Paleoclimatic Significance of Late Quaternary Lacustrine and Alluvial Stratigraphy, Animas Valley, New Mexico". Quaternary Research 50, n. 3 (novembre 1998): 283–89. http://dx.doi.org/10.1006/qres.1998.1997.
Testo completoAbstract (sommario):
Lacustrine and alluvial stratigraphic sequences in the southern Animas Valley of New Mexico allow reconstruction of late Quaternary climates. Four separate stands of late Quaternary Lake Cloverdale in the southern Animas Valley are recorded by lacustrine shoreline deposits. Soils and stratigraphic evidence show that three young lake highstands occurred during the Holocene and that a higher lake stand occurred 18,000 to 20,00014C yr B.P. Fluvial systems aggraded the southern Animas Valley during the middle to late Holocene. The late Quaternary stratigraphy shows that several periods during the late Holocene were characterized by higher effective precipitation than at any time since the last glacial maximum.
3
Litt, Thomas. "Vorwort/Preface". E&G Quaternary Science Journal 56, n. 1/2 (1 marzo 2007): 1–2. http://dx.doi.org/10.3285/eg.56.1-2.00.
Testo completoAbstract (sommario):
Abstract. In this volume, the Quaternary Subcommission of the German Stratigraphic Commission presents a description of the major stratotypes and stratigraphical terms for the Quaternary in Germany, focusing on climatostratigraphical terms that relate to cold and warm stages and have been incorporated into a regional chronostratigraphy.
4
Veillette, Jean J., e F. M. Nixon. "Sequence of Quaternary Sediments in the Bélanger Sand Pit, Pointe-Fortune, Québec-Ontario". Géographie physique et Quaternaire 38, n. 1 (29 novembre 2007): 59–68. http://dx.doi.org/10.7202/032536ar.
Testo completoAbstract (sommario):
ABSTRACT Drilling in the floor of the Bélanger sand pit (Ontario) near Pointe-Fortune, Québec, added 3 stratigraphic units to those already exposed in the pit: a lowermost till, and an intermediate organic-bearing (?) sand-clay unit overlain by a massive lacustrine clay. The subsurface units, comprising about 70% of the stratigraphy, complete the Quaternary sequence exposed in the pit face : an organic-bearing silty sand (>40 000 years BP) unit truncated by an unfos-siliferous sand unit and overlain by the uppermost till. The overall sequence forms a continuous 18 m column of Quaternary sediments. The Pointe-Fortune sequence shows some similarities with the Trois-Rivières Quaternary series which includes the Saint-Pierre sediments >75 000 years old. In addition to stratigraphie information the combination of direct (drilling) and indirect (geophysical) methods of investigation by providing a three-dimensional picture of the subsurface has proved helpful in interpreting the stratigraphy. The geotechnical properties of a massive overconsolidated clay have been determined to facilitate the planning of future subsurface investigation.
5
Shestopalov, Vyacheslav M., Oleksandr M. Ponomarenko e Stella B. Shekhunova. "IN MEMORIAM OF PROFESSOR PETRO F. GOZHIK, ACADEMICIAN OF THE NATIONAL ACADEMY OF SCIENCES OF UKRAINE". Collection of Scientific Works of the Institute of Geological Sciences of the NAS of Ukraine 14, n. 1 (20 maggio 2021): 5–16. http://dx.doi.org/10.30836/igs.2522-9753.2021.232269.
Testo completoAbstract (sommario):
This article is devoted to the blessed memory of Petro F. Gozhik, prominent Ukrainian scientist in the fields of paleontology, stratigraphy, marine geology, Winner of the State Prizes of Ukraine in Science and Technology (1989, 2000), Merited Figure of Science and Technology of Ukraine (1997), Laureate of NAS Tutkovsky Prize (2008), Director of the Institute of Geological Sciences of the NAS of Ukraine (1997–2020), President of the Paleontological Society of Ukraine, Chairman of the National Stratigraphic Committee of Ukraine, initiator and the first Director of the National Antarctic Research Center (previously the Center for Antarctic Research of the NAS of Ukraine), Doctor of Geological and Mineralogical Sciences (1993), Professor (2008), Academician of the NAS of Ukraine (2006). Scientific interests of P. F. Gozhik were diverse, but, first he was an outstanding paleontologist and stratigrapher, Quaternary geologist, a renowned researcher of the Neogene — Quaternary fossil freshwater mollusks of the south of Eastern Europe. His works in Quaternary stratigraphy, paleogeography and the geological history of continental Ukraine and the Black Sea, the study of Quaternary mollusks, continental (alluvial, glacial, water-glacial, loess) and estuarine sediments became tabletop reference books.
6
Zhu, Jixiang, Xiaoyuan Zhou, Guanghui Zhang e Qian Wang. "Quaternary Depositional Framework of the Xiong’an New Area: A 3D Geological Modeling Approach Based on Vector and Grid Integration". Sustainability 14, n. 6 (14 marzo 2022): 3409. http://dx.doi.org/10.3390/su14063409.
Testo completoAbstract (sommario):
The Quaternary stratigraphic unit is an important underground space resource for sustainable urban development. It is of great significance to understand the spatial variation characteristics of the Quaternary stratigraphic structure and its internal attributes. However, due to the openness and complexity of the Quaternary sedimentary environment, the sedimentary characteristics of Quaternary stratigraphic units are often very complex and difficult to accurately analyze. In this study, a method for analyzing Quaternary sedimentary characteristics via 3D geological modeling based on vector and grid integration is proposed. Based on this method, the Quaternary depositional framework of Xiong’an New Area is established. The results show that the study area is mainly composed of seven Quaternary strata with different sedimentary origins, and the 3D spatial variation characteristics of lithology in each stratum are unique. Taking the vector framework model as the constraint boundary, this study constructs the lithology stochastic model of each Quaternary stratigraphic unit respectively, and accurately simulates the 3D spatial variation characteristics of the inner lithology of Quaternary stratigraphic units in the study area, which is of great significance for the urban planning, construction, and environmental protection of Xiong’an New Area.
7
Zolnikov, I. D., A. V. Shpansky e M. V. Mikharevich. "PROBLEMS OF THE QUATERNARY STRATIGRAPHY OF THE SIBERIAN REGION". Geology and mineral resources of Siberia, n. 10s (dicembre 2021): 3–6. http://dx.doi.org/10.20403/2078-0575-2021-10c-3-6.
Testo completoAbstract (sommario):
This special issue of the journal is devoted to modern controversial subjects arising during the research of the Siberian Quaternary system. The initiative to discuss these problems and new factual material that requires rethinking outdated stratigraphic constructions belonged to the section of the Quaternary system of SIBRMSK and was supported by leading experts actively working in the region. It should be noted that this issue does not cover all the unresolved issues on the geology, stratigraphy and paleogeography of the Quaternary period of Siberia.
8
Zerkal, O. V., R. R. Gabdullin e E. N. Samarin. "Problems of the quaternary geologyof the Crimean peninsula central part at the present time". Moscow University Bulletin. Series 4. Geology, n. 3 (28 giugno 2017): 27–34. http://dx.doi.org/10.33623/0579-9406-2017-3-27-34.
Testo completoAbstract (sommario):
In the study of Quaternary deposits of the Crimea selected two phases. In the first stage (since the late XIX century to the sixties of XX century) stratigraphic description of the Quaternary strata was based on the allocation of terraced complexes (a marine terraces - in the coastal part and synchronous them alluvial ones - in continental part of the Crimean peninsula). In the second stage description of the Quaternary deposits is made on the basis of their climatic and stratigraphic dissection under the leading role of the loess-soil formation structure. The basis for stratigraphic subdivision of Quaternary deposits of the Crimea was the structure of the valleys of the paleo-Dnieper and paleo-Dniester. It is shown that the nonlinear, reversible character of Black sea level changes that took place in the Quaternary can be broken a rule “the lower the hypsometrically level of the terrace is, the younger this terrace is”.
9
Lewin, John, Mark G. Macklin e Jamie C. Woodward. "Late Quaternary Fluvial Sedimentation in the Voidomatis Basin, Epirus, Northwest Greece". Quaternary Research 35, n. 1 (gennaio 1991): 103–15. http://dx.doi.org/10.1016/0033-5894(91)90098-p.
Testo completoAbstract (sommario):
AbstractDetailed morpho- and lithostratigraphic investigations, allied with radiometric dating, in the Voidomatis basin, Epirus, northwest Greece, have identified four Quaternary terraced alluvial fills that range from middle Pleistocene to historic in age. Major-periods of alluviation during the late Quaternary were associated with valley glaciation (ca. 26,000–20,000 yr B.P.) and subsequent deglaciation (ca. 20,000–15,000 yr B.P.) in the Pindus Mountains during Late Würmian times, and more recently linked to overgrazing sometime before the 11th century AD. The late Quaternary alluvial stratigraphy of the Voidomatis River is more complex than the “Older Fill” and “Younger Fill” model outlined previously, and it is suggested that these terms should no longer form the basis for defining alluvial stratigraphic units in the Mediterranean Basin.
10
Tian, Shaobing, Ping Zhang, Tongxiao Shang, Huogen Chen, Yongxiang Li e Shugang Xu. "Application of resistivity sounding in Quaternary stratigraphic division in Yixing, Eastern China". Journal of Geophysics and Engineering 19, n. 3 (1 giugno 2022): 362–75. http://dx.doi.org/10.1093/jge/gxac025.
Testo completoAbstract (sommario):
Abstract Stratigraphic classification and correlation are fundamental for the study of regional geology, tectonic structures and paleogeographic evolution. Geological structures have undergone a dramatic change since the Quaternary. However, the division of the Quaternary stratigraphic boundary in southeastern China is debated. In this study, we used a direct current vertical electric sounding method to study the Quaternary strata in Yixing, Jiangsu, China. Using one-dimensional resistivity inversion and analyzing the regional geology and geological core data, the electrical features of the study area were evaluated. We found good agreement between the geological core data and lithological data, and we were able to identify two stratigraphic groups: the hilly sedimentary area in the southwest and the Tai Lake plain sedimentary area in the northeast. The latter can further subdivided into two parts. Division and classification of the Quaternary strata in the study area provide a basis for locating areas likely to have a high pore-confined water content (such as Gaoteng, Heqiao and Wanshi town), whereby useful information is provided for groundwater exploitation for emergency use.
11
Slupik, A. A., F. P. Wesselingh, A. C. Janse e J. W. F. Reumer. "The stratigraphy of the Neogene-Quaternary succession in the southwest Netherlands from the Schelphoek borehole (42G4-11/42G0022) – a sequence-stratigraphic approach". Netherlands Journal of Geosciences - Geologie en Mijnbouw 86, n. 4 (dicembre 2007): 317–32. http://dx.doi.org/10.1017/s0016774600023556.
Testo completoAbstract (sommario):
AbstractWe investigate the stratigraphy of Neogene and Quaternary intervals of the Schelphoek borehole (Schouwen, Zeeland, the Netherlands). The Breda Formation (Miocene-Zanclean) contains three sequences separated by hiatuses. The Oosterhout Formation (Zanclean-Piacenzian) contains at least two sequences. This formation is overlain by seven sequences of the Gelasian Maassluis Formation that almost certainly represent glacial cycles. The three lowermost sequences are provisionally assigned to the Praetiglian (MIS 96, MIS 98 and MIS 100). A large hiatus exists between the top of the Maassluis Formation and the base of the late Middle to Late Quaternary succession. Due to extensivein situreworking of older strata (including fossils) at the base of several of the formations, their exact boundaries are difficult to establish. The Neogene succession in the Schelphoek borehole is compared to the stratigraphic successions in the Antwerp area to the south and the Dutch coastal area and continental platform to the north. Finally, the stratigraphic context of the Gelasian (‘Tiglian’) mammal fauna dredged from the bottom of a major tidal channel in the adjacent Oosterschelde is assessed by comparison with the Schelphoek borehole.
12
Маtveyev, A. V., Т. B. Rylova, S. V. Demidova e Т. V. Yakubovskaya. "Changes in stratigraphic charts of neogene and quaternary deposits of Belarus due to the revision of the boundary between systems". Doklady of the National Academy of Sciences of Belarus 63, n. 3 (28 giugno 2019): 350–59. http://dx.doi.org/10.29235/1561-8323-2019-63-3-350-359.
Testo completoAbstract (sommario):
Following the decision of the International Union of Geological Sciences on the transfer of the lower boundary of the Quaternary System/Period and the Pleistocene Series/Epoch from 1.8 Ma to 2.58 Ma (to the base of the Gelazian Stage/ Age of the Pliocene), the changes have been made in Stratigraphic charts of Neogene and Quaternary Deposits of Belarus (2010). The Neogene – Quaternary boundary in the territory of Belarus is aligned with the International Chronostratigraphic Chart and is made between the Kholmech horizon (analogue of Zanclean and Piacenzian, Pliocene) and the Dvorets horizon (analogue of Gelasian) displaced from the Pliocene to the lower base of the lowermost Pleistocene. Its new position in the sections is substantiated by paleobotanical data. New geological units were introduced into regional and local stratigraphic charts of the Neogene and Quaternary.
13
Burney, David A. "Late Quaternary Stratigraphic Charcoal Records from Madagascar". Quaternary Research 28, n. 2 (settembre 1987): 274–80. http://dx.doi.org/10.1016/0033-5894(87)90065-2.
Testo completoAbstract (sommario):
AbstractThe classic view regarding the cause of the extinction of at least 17 species of large mammals, birds, and reptiles in Madagascar during the late Holocene implicates human use of fire to modify the environment. However, analysis of the charcoal stratigraphy of three sediment cores from Madagascar shows that late Pleistocene and early- to mid-Holocene sediments deposited prior to human settlement often contain more charcoal than postsettlement and modern sediments. This observation, which is confirmed by independent measurements from direct assay and palynological counting techniques, suggests that widely held but previously untested beliefs concerning the importance of anthropogenic fires in late Holocene environmental changes and megafaunal extinctions of Madagascar may be based on an overly simplified version of actual prehistoric conditions. Moderate to low charcoal values characterized only the late Holocene millennia immediately prior to the presumed time of arrival of the first settlers. Human settlement is probably indicated in the stratigraphy by the sharp rise in charcoal content observed beginning ca. 1500 yr B.P. Fire appears to be a significant natural component of prehuman environments in Madagascar, but some factor, probably climate, has modulated the extent of natural burning.
14
Long, Joshua H., Till J. J. Hanebuth e Thomas Lüdmann. "The Quaternary stratigraphic architecture of a low-accommodation, passive-margin continental shelf (Santee Delta region, South Carolina, U.S.A.)". Journal of Sedimentary Research 90, n. 11 (30 novembre 2020): 1549–71. http://dx.doi.org/10.2110/jsr.2020.006.
Testo completoAbstract (sommario):
ABSTRACT The Quaternary stratigraphy of the continental shelf offshore of South Carolina consists of stratigraphic units deposited in coastal-plain, shallow marine, and shelfal environments bounded by composite erosional surfaces that developed in response to numerous glacioeustatic cycles and were overprinted by regional uplift. These units are commonly distributed laterally, rather than stacked vertically, a function of the long-term low shelf gradient and the resulting lack of accommodation. Additionally, marine processes such as waves and geostrophic currents can rework both relict and modern sediments across the continental shelf. This study integrates high-resolution geological and geophysical datasets acquired offshore and onshore with existing data onshore into a comprehensive conceptual model describing the Quaternary geologic evolution of the coastal plain and continental shelf within a study area of approximately 8,000 km2. We use seismic facies and core analysis to define stratigraphic units associated with transgressive, regressive, and lowstand systems offshore. Regressive systems include progradational wave- and river-dominated deltaic and shoreface deposits. Lowstand systems consist of a complex network of paleo-incisions produced by regional, Piedmont-draining fluvial systems and smaller coastal plain rivers. Transgressive systems include paleochannel-fill successions dominated by mud-rich, tidally influenced backbarrier deposits, cuspate and linear shelf sand ridges, and transgressive sand sheets and shoals. The low-accommodation setting of the continental shelf influences the stratigraphic record in several ways: 1) the geometry of progradational coastal lithosomes, 2) the development of composite allogenic erosional surfaces, 3) the deposition of widespread, thin transgressive sand sheets, and 4) the restriction of thicker transgressive deposits to paleo-incisions. In this setting, the use of a bounding surface scheme that is hierarchical is preferable to the more common sequence stratigraphic or allostratigraphic convention for several reasons: 1) major erosional bounding surfaces are commonly amalgamated; 2) lower-order surfaces capture internal variability, which is key to the genetic interpretation of stratigraphic units, and 3) stratal stacking patterns typically used to define a sequence stratigraphic framework are rare.
15
Aiello, Gemma. "Quaternary Lowstand Prograding Wedges of the Salento Continental Shelf (Southern Adriatic Sea, Italy): Architectural Stacking Patterns and the Control of Glacio-Eustatic Sea Level Fluctuations and Foreland Tectonic Uplift". Geosciences 13, n. 1 (22 dicembre 2022): 4. http://dx.doi.org/10.3390/geosciences13010004.
Testo completoAbstract (sommario):
The performance of both the tectonic uplift and of the 4th-order glacial eustatic sea level fluctuations in controlling the stratigraphic architecture of Quaternary lowstand prograding wedges of the Salento continental shelf (Southern Adriatic sea, Italy) during a time interval spanning from the Middle Pleistocene to the Holocene has been pointed out through the interpretation of high-resolution seismic reflection profiles and their correlation to the curves of the isotopic stratigraphy. Three main transgressive surfaces of erosion (RS1, RS2 and RS3) punctuate the stratigraphic architecture of the Salento continental shelf, separating Quaternary lowstand prograding wedges between them. All along the Middle Pleistocene, increasing the tectonic uplift of the Puglia offshore, combining with 4th-order glacio-eustatic variations, have dealt with the pattern of a broad forced regression prograding wedge, favoring a platform progradation of approximately 15 km. The architectural stacking patterns of the overlying Late Pleistocene and Holocene prograding wedges are controlled by 4th-order glacio-eustatic sea level changes, allowing for the formation of incomplete depositional sequences. In this period, the eustatic signature overcomes the tectonic mark, implying a decline in the uplift of the Apulian foreland in the course of the final 250 ky.
16
Aiello, Gemma. "Submarine Stratigraphy of the Eastern Bay of Naples: New Seismo-Stratigraphic Data and Implications for the Somma-Vesuvius and Campi Flegrei Volcanic Activity". Journal of Marine Science and Engineering 10, n. 10 (18 ottobre 2022): 1520. http://dx.doi.org/10.3390/jmse10101520.
Testo completoAbstract (sommario):
The submarine stratigraphy of the eastern Bay of Naples is studied through seismo-stratigraphic data correlated with borehole data. Multichannel seismic profiles are interpreted in order to reconstruct the stratigraphic relationships between the Quaternary marine seismic units and the volcanic acoustic substratum. Seven seismic units are recognized based on the geological interpretation of seismic profiles and using seismo-stratigraphic criteria. The top of the lowest seismic unit was correlated with the Campanian Ignimbrite (Southern Campania Volcanic Zone). The stratigraphic setting of the eastern Bay of Naples is characterized by NE-SW trending seismic structures, probably corresponding with tuff rings. These tuff rings can be compared with the Porto Miseno, the Archiaverno and Averno, and the Astroni tuff rings (Campi Flegrei). Offshore, the Somma-Vesuvius a seismic unit was interpreted as the fallout deposits representing the base of the AD 79 eruption. However, since a branch of the isopach of 5 m of the “Pomici di Avellino” pyroclastic deposits is very close to the Tyrrhenian coastline and near our GRNA01 and GRNA03 seismic profiles, we cannot exclude that the seismic unit could be also correlated with the deposits of this eruption.
17
Zhu, Jixiang, Yan Lu, Guanghui Zhang, Xiaoyuan Zhou e Guangjun Ji. "Study on the Construction of 3D Geological Model of Quaternary Loose Sedimentary Strata Based on the Global Stratigraphic Discrete Points". Water 14, n. 1 (2 gennaio 2022): 75. http://dx.doi.org/10.3390/w14010075.
Testo completoAbstract (sommario):
Accurately depicting the spatial structure characteristics of Quaternary loose sedimentary strata is not only of great significance for the research of Quaternary geological evolution, but also for the analysis of spatial variation characteristics of the inner hydrogeological and engineering geological attributes of the strata. In this study, an approach for constructing a 3D geological model of Quaternary loose sedimentary strata is proposed based on global stratigraphical discrete points. The approach obtains the discrete control point set of each stratum by using limited borehole data for interpolation and encryption, and the contact relationships and intersection modes of adjacent strata can be determined via the analysis of stratigraphic sequence; finally, taking these as the professional basis, the construction of the 3D geological model of Quaternary loose sedimentary strata can be carried out. This application can not only accurately describe the three-dimensional spatial distribution characteristics of the Quaternary loose sedimentary strata, it can also be used to perform a layered simulation of the spatial variation characteristics of the inner geological properties of the Quaternary loose sedimentary strata, such as lithology, porosity, and water content, by taking the three-dimensional spatial framework of each stratum as the simulation boundary. Finally, this study takes the citizen center of Xiong’an new area as an example in order to verify the reliability and advancement of the 3D geological modeling scheme.
18
Gaudenyi, Tivadar, Drazenko Nenadic, Mladjen Jovanovic e Petar Stejic. "The revision of quaternary stratigraphy of the Zrenjanin artesian well borehole profile (Banat, Vojvodina, Serbia)". Annales g?ologiques de la Peninsule balkanique, n. 00 (2022): 7. http://dx.doi.org/10.2298/gabp210306007g.
Testo completoAbstract (sommario):
The geological analysis of artesian borehole material from Sombor, Subotica, and Zrenjanin, was in the first campaign of detailed stratigraphic studies of Vojvodina in 1892-1895. The results of Quaternary stratigraphy from Zrenjanin were published by HalavAts m ore than a decade later (1914). The significance of the Zrenjanin, Sombor, and Subotica artesian well profiles for more than a century is considered the representative local profiles for the Quaternary stratigraphy of Vojvodina recognized by Serbian (Yugoslavian) and Hungarian geologists. Significant changes were after the taxonomical revision of molluscan material and its stratigraphic context, which was done through the excellent work of Krolopp in the 1970-ies. Unfortunately, the mentioned changes were not applied in the studies during the geological surveying of former Yugoslavia. The developments in Quaternary geology, changes in the Quater nary chronostratigraphic scale, and the results shown by this paper enable the Lower Pleistocene fluvial deposits to be defined as the Pleistocene Corbicula beds, the Viviparus boeckhi Horizon. The Lower Pleistocene at Zrenjanin was documented from 234.54 to 58.36 m depth. The interval between 234.54 and 208.50 m comprises the Upper Paludina - Viviparus vucotinovici zone, while the Viviparus boeckhi Horizons were identified between 135.18 m and 58.36 m. The interval between 58.36 m and 37.75 m is defined as Pleistocene (Lower- and Middle Pleistocene) based on sedimentological and the molluscan record. The interval from 37.75 m to 21.67 m depth was identified as Middle Pleistocene, according to its lithology and the paleontological material. The fluvial sediments? 21.69 m and 7.31 m depths cannot be determined according to the faunistic data; we can only consider them as Pleistocene age. The Holocene sediment and soil horizons ascend to a 2.90 m depth.
19
Panagopoulos, G., E. Giannakakos, E. Manoutsoglou, E. Steiakakis, P. Soupios e A. Vafidis. "Definition of inferred faults using 3D geological modeling techniques: A case study in Tympaki Basin in Crete, Greece". Bulletin of the Geological Society of Greece 47, n. 2 (24 gennaio 2017): 605. http://dx.doi.org/10.12681/bgsg.11087.
Testo completoAbstract (sommario):
The purpose of this paper is to recognize inferred faults in Tympaki basin (Crete island) which cannot be observed on the surface, as the area is covered by recent deposits. The identification of the faults is crucial for the study of the sea-water intrusion in Tympaki basin that has been observed during the last years. 3D geological modelling techniques were used for reaching the aforementioned goal. The data used include the digital elevation model (DEM) of the area, the boundary surface between geologic formations and the litho - stratigraphic logs of thirty nine (39) wells. Initially a 3D stratigraphic model was set-up depicting the spatial extension of Plio-Quaternary and Neogene deposits. Next, with emphasis on the litho - stratigraphic logs of the wells, the boundary between the geological formations was defined in a 3D space. The regional unconformity between the Plio-Quaternary and Neogene formations is possibly the result of tectonic activity of inferred faults. The traces of the inferred faults were drawn and they were compared with the faults suggested by previous studies.
20
Prest, V. K. "General stratigraphic framework of the Quaternary in Eastern Canada". Cadre stratigraphique et paléoclimatique 31, n. 1-2 (9 dicembre 2010): 7–14. http://dx.doi.org/10.7202/1000051ar.
Testo completoAbstract (sommario):
In eastern Canada, inter-glacial and interstadial deposits have been reported from Nova Scotia and Québec, but in the other provinces only Wisconsinan deposits. In Nova Scotia, pollen from some organic deposits buried beneath one or more tills, indicates a warm, interglacial climate — presumably the Sangamon Interglacial Interval. Other buried organic deposits, in contrast, indicate a cool, boreal forest environment. As radiocarbon analyses have given 'greater than' dates the deposits are considered to be early Wisconsinan. The interval is tentatively correlated with the St. Pierre Interstadial of Québec. The only known mid-Wisconsinan deposit is at Salmon River on St. Mary's Bay, in southwestern Nova Scotia, where the marine shells have been dated at 38,600,4C years. Elsewhere in both coastal and interior Nova Scotia multiple till sections suggest a more or less continuous ice cover through-out the Wisconsinan. In central Nova Scotia, however, red tills have been considered late-Wisconsinan. In Québec, there is a very limited, but nevertheless important, record of the Sangamon Interglacial Interval. Compact clayey rhythmites in the Harricana River Basin, close to James Bay, appear to correlate with the lacustrine member of the Missinaibi Formation farther west in Ontario. In southern Québec, there is another indication of interglacial deposits for the oldest sediments exposed in the Sherbrooke region and in the Upper Chaudière River Valley beneath the lowest of three Wisconsinan tills. These deposits were weathered and cemented prior to deposition of the oldest till. As the gravels contain pebbles of Laurentian Shield gneiss there obviously was a pre-Sangamon glaciation. These two areas contain the most complete stratigraphie record of the Wisconsinan yet established in Québec.
21
Wang, Jinyan, e Jianqiang Chen. "Quaternary Sedimentary Stratigraphic Sequence of Changzhou and Its Significance". IOP Conference Series: Earth and Environmental Science 170 (luglio 2018): 022060. http://dx.doi.org/10.1088/1755-1315/170/2/022060.
Testo completo
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Pashko, Pandeli, e Shyqyri Aliaj. "Stratigraphy and tectonic evolution of Late Miocene - Quaternary Basins in Eastern Albania: A Review". Bulletin of the Geological Society of Greece 56, n. 1 (28 dicembre 2020): 317. http://dx.doi.org/10.12681/bgsg.22064.
Testo completoAbstract (sommario):
The new stratigraphic data and tectonic evolution of the Late Miocene-Quaternary basins developed in Eastern Albania are presented. The reviewed stratigraphic data for deposits filling the Ohrid, Prespa and Devolli basins show that they began to form in Late Miocene. The stratigraphic evidences from eastern Albania are confronted with the stratigraphic data from the lake basins in western North Macedonia and northwestern Greece that all show the same age of infilling. The Cenozoic tectonic evolution of Eastern Albania consists of two phases of extensional deformations, the first in Middle Eocene-Late Miocene (Pannonian/Tortonian) and the second starting in Late Miocene (Pontian s. l.). The two phases are separated by a short compressive phase at the Late Miocene (end of Pannonian/Tortonian) or pre-Pontian s. l. time. In Late Miocene (Pontian) began forming the system of the Ohrid, Prespa and Devolli basins developed along the Drini fault zone. The Korça, Kolonja, Kukesi and Tropoja basins began to form since Pliocene and the Peshkopi Basin since Early Pleistocene. Finally, only the Ohrid and Prespa lakes are still active. The Late Miocene-Pleistocene basins were filled by lacustrine, lacustrine-fluvial and terrestrial sediments of the great thickness and of varied lithology: conglomerates, gravels, sandstones, sands, claystone and marls with lignite seams. Molluscs, microflora and flora, ostracods and vertebrates are found. The Lake Ohrid is a tectonically active graben formed during two main phases of deformation: (1) a trans-tensional phase which generated a pull-apart basin, and (2) an extensional phase which leads to its present geometry. All basins in Eastern Albania are situated in a basin and range-like (graben and horst) geodynamical setting. The inferred stratigraphic and tectonic evolution of Late Miocene-Quaternary basins in Eastern Albania as well as the relief formation and thermochronological data show that the Late Miocene-Quaternary period which led to the recent geological structure of Albania and its rapid relief formation, can be accepted as ‘Neotectonic period’.
23
Pashko, Pandeli, e Shyqyri Aliaj. "Stratigraphy and tectonic evolution of Late Miocene - Quaternary Basins in Eastern Albania: A Review". Bulletin of the Geological Society of Greece 56, n. 1 (28 dicembre 2020): 317. http://dx.doi.org/10.12681/bgsg.22064.
Testo completoAbstract (sommario):
The new stratigraphic data and tectonic evolution of the Late Miocene-Quaternary basins developed in Eastern Albania are presented. The reviewed stratigraphic data for deposits filling the Ohrid, Prespa and Devolli basins show that they began to form in Late Miocene. The stratigraphic evidences from eastern Albania are confronted with the stratigraphic data from the lake basins in western North Macedonia and northwestern Greece that all show the same age of infilling. The Cenozoic tectonic evolution of Eastern Albania consists of two phases of extensional deformations, the first in Middle Eocene-Late Miocene (Pannonian/Tortonian) and the second starting in Late Miocene (Pontian s. l.). The two phases are separated by a short compressive phase at the Late Miocene (end of Pannonian/Tortonian) or pre-Pontian s. l. time. In Late Miocene (Pontian) began forming the system of the Ohrid, Prespa and Devolli basins developed along the Drini fault zone. The Korça, Kolonja, Kukesi and Tropoja basins began to form since Pliocene and the Peshkopi Basin since Early Pleistocene. Finally, only the Ohrid and Prespa lakes are still active. The Late Miocene-Pleistocene basins were filled by lacustrine, lacustrine-fluvial and terrestrial sediments of the great thickness and of varied lithology: conglomerates, gravels, sandstones, sands, claystone and marls with lignite seams. Molluscs, microflora and flora, ostracods and vertebrates are found. The Lake Ohrid is a tectonically active graben formed during two main phases of deformation: (1) a trans-tensional phase which generated a pull-apart basin, and (2) an extensional phase which leads to its present geometry. All basins in Eastern Albania are situated in a basin and range-like (graben and horst) geodynamical setting. The inferred stratigraphic and tectonic evolution of Late Miocene-Quaternary basins in Eastern Albania as well as the relief formation and thermochronological data show that the Late Miocene-Quaternary period which led to the recent geological structure of Albania and its rapid relief formation, can be accepted as ‘Neotectonic period’.
24
Cooper, A. J. "Waste disposal site selection techniques in Quaternary terraine Ontario, Canada". Geological Society, London, Engineering Geology Special Publications 7, n. 1 (1991): 211–17. http://dx.doi.org/10.1144/gsl.eng.1991.007.01.19.
Testo completoAbstract (sommario):
AbstractThick and predictable deposits of fine grained Quaternary materials have been used for the siting of waste management facilities in Ontario. The search for such sites is founded on the application of techniques in Quaternary geology and hydrogeology. Two examples are presented. Oxford County is located southwest of Toronto in an area of parallel morainic ridges separated by flat till plains. Conventional wisdom would focus on the till plains for thick, consistent fine grained Quaternary Sediments. However, the careful analysis of the Quaternary stratigraphy and glacial history revealed that better sites are located along the moraines. A site on the Ingersoll Moraine was studied in detail and defended at a public hearing. Concerns about the geology of the materials were allayed by the confirmation of homogeneous clayey silt materials exposed when the site opened in late 1986. A much wider ranging search was undertaken for a major hazardous and liquid industrial waste treatment and disposal facility for the Province of Ontario. Progressively more detailed investigations of the Quaternary geology were used to assist a multi-disciplinary site selection team. Initial interpretations covered an area of 75 000 km2 at a scale of 1:250 000. Eight candidate sites were then selected for further investigation with five continuously sampled stratigraphic boreholes. The chosen site is located in a depression in the bedrock filled with 40 m of glaciolacustrine clayey silt. Site specific hydrogeological and geotechnical studies were integrated with a detailed geological investigation.
25
Karrow, Paul F., Aleksis Dreimanis e Peter J. Barnett. "A Proposed Diachronic Revision of Late Quaternary Time-Stratigraphic Classification in the Eastern and Northern Great Lakes Area". Quaternary Research 54, n. 1 (luglio 2000): 1–12. http://dx.doi.org/10.1006/qres.2000.2144.
Testo completoAbstract (sommario):
A succession of stratigraphic codes (1933, 1961, 1983) has guided attempts to refine classifications and naming of stratigraphic units for Quaternary deposits of the Great Lakes region. The most recent classifications for the late Quaternary of the Lake Michigan lobe (1968) and the eastern Great Lakes (1972) have been widely used, but later work has created the need for revision. An attempt has been made to integrate the two previous classifications following the diachronic system of the 1983 Code of Stratigraphic Nomenclature. A new nomenclature for the higher, more broadly recognized units was presented in 1997. We here present the diachronic nomenclature for finer subdivisions recognized in the eastern and northern Great Lakes. Following the interglacial Sangamon Episode, the three parts of the Wisconsin Episode are further subdivided as follows: the Ontario Subepisode (former Early Wisconsinan) comprises the Greenwood, Willowvale, and Guildwood phases; the Elgin Subepisode (former Middle Wisconsinan) comprises the Port Talbot, Brimley, and Farmdale phases; and the Michigan Subepisode (former Late Wisconsinan) consists of Nissouri, Erie, Port Bruce, Mackinaw, Port Huron, Two Creeks, Onaway, Gribben, Marquette, Abitibi, and Driftwood phases. Succeeding interglacial time to the present is the Hudson Episode.
26
Mangan, Margaret T., Christopher F. Waythomas, Thomas P. Miller e Frank A. Trusdell. "Emmons Lake Volcanic Center, Alaska Peninsula: source of the Late Wisconsin Dawson tephra, Yukon Territory, Canada". Canadian Journal of Earth Sciences 40, n. 7 (1 luglio 2003): 925–36. http://dx.doi.org/10.1139/e03-026.
Testo completoAbstract (sommario):
The Emmons Lake Volcanic Center on the Alaska Peninsula of southwestern Alaska is the site of at least two rhyolitic caldera-forming eruptions (C1 and C2) of late Quaternary age that are possibly the largest of the numerous caldera-forming eruptions known in the Aleutian arc. The deposits produced by these eruptions are widespread (eruptive volumes of >50 km3 each), and their association with Quaternary glacial and eolian deposits on the Alaska Peninsula and elsewhere in Alaska and northwestern Canada enhances the likelihood of establishing geochronological control on Quaternary stratigraphic records in this region. The pyroclastic deposits associated with the second caldera-forming eruption (C2) consist of loose, granular, airfall and pumice-flow deposits that extend for tens of kilometres beyond Emmons Lake caldera, reaching both the Bering Sea and Pacific Ocean coastlines north and south of the caldera. Geochronological and compositional data on C2 deposits indicate a correlation with the Dawson tephra, a 24 000 14C BP (27 000 calibrated years BP), widespread bed of silicic ash found in loess deposits in west-central Yukon Territory, Canada. The correlation clearly establishes the Dawson tephra as the time-stratigraphic marker of the last glacial maximum.
27
Corrado, Giuseppe, Sabrina Amodio, Pietro P. C. Aucelli, Gerardo Pappone e Marcello Schiattarella. "The Subsurface Geology and Landscape Evolution of the Volturno Coastal Plain, Italy: Interplay between Tectonics and Sea-Level Changes during the Quaternary". Water 12, n. 12 (2 dicembre 2020): 3386. http://dx.doi.org/10.3390/w12123386.
Testo completoAbstract (sommario):
The Volturno alluvial-coastal plain is a relevant feature of the Tyrrhenian side of southern Italy. Its plan-view squared shape is due to Pliocene-Quaternary block-faulting of the western flank of the south-Apennines chain. On the basis of the stratigraphic analysis of almost 700 borehole logs and new geomorphological survey, an accurate paleoenvironmental reconstruction before and after the Campania Ignimbrite (CI; about 40 ky) eruption is here presented. Tectonics and eustatic forcing have been both taken into account to completely picture the evolution of the coastal plain during Late Quaternary times. The upper Pleistocene-Holocene infill of the Volturno plain has been here re-organized in a new stratigraphic framework, which includes seven depositional units. Structural analysis showed that two sets of faults displaced the CI, so accounting for recent tectonic activity. Yet Late Quaternary tectonics is rather mild, as evidenced by the decametric vertical separations operated by those faults. The average slip rate, which would represent the tectonic subsidence rate of the plain, is about 0.5 mm/year. A grid of cross sections shows the stratigraphic architecture which resulted from interactions among eustatic changes, tectonics and sedimentary input variations. On the basis of boreholes analysis, the trend of the CI roof was reconstructed. An asymmetrical shape of its ancient morphology—with a steeper slope toward the north-west border—and the lack of coincidence between the present course of the Volturno River and the main buried bedrock incision, are significant achievements of this study. Finally, the morpho-evolutionary path of the Volturno plain has been discussed.
28
Amador, Elmo Da Silva. "Geologia e Geomorfologia da Planície Costeira da Praia do Sul: Ilha Grande - Uma Contribuição à Elaboração do Plano Diretor da Reserva Biológica". Anuário do Instituto de Geociências 11 (1 gennaio 1987): 35–58. http://dx.doi.org/10.11137/1987_0_35-58.
Testo completoAbstract (sommario):
Based on stratigraphical, sedimentological and geomorphological methods, a preliminary stratigraphic division is proposed to the Praia do Sul coastal plain, a state Biological Reserve, located in "Ilha Grande", Rio de Janeiro. This reserve was created to preserve the natural ecosystems found therein (sandy coastal plain, mangrove, lagoon, rocky coast and hillside fo rest). The Praia do Sul sedimentation plain is essentially constituted by continental gravels and sands of Upper Pleistocene, marine sandy formations, fluvial-lagoonal sandy-clayer formations and present mangrove swamps and beachs. The paleogeographic evolution of this area can be followed through the sedimentary association that permits to establish the transgressive and regressive process that occured during the Quaternary period.
29
Bittmann, Felix, Andreas Börner, Gerhard Doppler, Dietrich Ellwanger, Christian Hoselmann, Lutz Katzschmann, Tobias Sprafke, Jaqueline Strahl, Stefan Wansa e Ulrike Wielandt-Schuster. "Die Stratigraphische Tabelle von Deutschland 2016 (STD 2016)". Zeitschrift der Deutschen Gesellschaft für Geowissenschaften 169, n. 2 (26 luglio 2018): 295–306. http://dx.doi.org/10.1127/zdgg/2018/0123.
Testo completo
30
Mikharevich, M. V., e A. V. Shpansky. "PROBLEMS OF AGE AND GENETIC DIAGNOSTICS OF QUATERNARY DEPOSITS IN THE VALLEY OF THE YENISEI RIVER MIDDLE COURSE (YENISEI – LOWER ANGARA STRATIGRAPHIC REGION AND THE MINUSINSK BASINS AREA)". Geology and mineral resources of Siberia, n. 10s (dicembre 2021): 57–68. http://dx.doi.org/10.20403/2078-0575-2021-10c-57-68.
Testo completoAbstract (sommario):
The article is devoted to the state of stratigraphic exploration maturity of the Eopleistocene – Neo-Рleistocene Quaternary deposits on the boundary of mountain and plain territories in the non-glacial area. The material analysis shows an inadequate rationale of the existing stratigraphic schemes, according to which the ladder of alluvial terraces of these territories was formed sequentially during the Eopleistocene, Neo-Pleistocene and Holocene. The revising of representative sections was carried out, the provision of them with geochronological data, the accuracy of age and genetic diagnostics were evaluated.
31
Lucà, Federica, Andrea Brogno, Vincenzo Tripodi e Gaetano Robustelli. "Terrace Morpho-Sedimentary Sequences on the Sibari Plain (Calabria, Southern Italy): Implication for Sea Level and Tectonic Controls". Geosciences 12, n. 5 (16 maggio 2022): 211. http://dx.doi.org/10.3390/geosciences12050211.
Testo completoAbstract (sommario):
The Sibari Plain (northeastern Calabria) shows a well-developed stair of late Quaternary marine/coastal terraces resulting from the interaction between sea level fluctuations and tectonic uplift. This paper (i) provides a stratigraphic description of terraced deposits between the Raganello and Coscile rivers, (ii) assesses the relative controls of eustacy and uplift on the staircase formation, and (iii) unravels the Quaternary morphosedimentary evolution of the study area. A geomorphological approach was coupled with stratigraphic field surveys. Photo interpretation, topographic map analyses, and field surveys allowed us to map ten orders of terraces forming telescopically incised valley-fills. Based on the uppermost position of foreshore deposits on inner margins and an average uplift rate of ~1 mm/y, inferred from the Marine Isotope Stage (MIS) 5.5, terraces were correlated with highstands. Sedimentological and stratigraphic analyses allowed us to recognize four assemblages of genetically associated sedimentary facies related to superimposed and juxtaposed coastal and alluvial systems, showing a seaward-stepping architecture. Based on stratal geometry and facies association, we argue that alluvial/fluvial sediments and coastal depositional systems formed contemporaneously along the same terrace. Terrace arrangement resulted from repeated cycles of valley incision (sea level fall) and aggradational to progradational stacking pattern (sea level rise and highstands) in a framework of sustained uplift.
32
Josenhans, H. W., J. Zevenhuizen e R. A. Klassen. "The Quaternary geology of the Labrador Shelf". Canadian Journal of Earth Sciences 23, n. 8 (1 agosto 1986): 1190–213. http://dx.doi.org/10.1139/e86-116.
Testo completoAbstract (sommario):
The regional distribution of glacial and postglacial sediments on the Labrador Shelf was mapped by medium- and high-resolution seismics and shows a succession of tills that extend to the continental shelf edge at approximately 600 m. The uppermost of these tills is less laterally extensive and does not occur on the Labrador Shelf bank tops in water depths less than 160 m. We infer that the last glacial episode was less extensive than the preceding ones. Glaciomarine stratified silts and postglacial muds are found overlying the upper till in the deep basins that separate the banks. The upper till, glaciomarine silts, and postglacial muds are interpreted to constitute one complete deglacial cycle. Radiocarbon age determination suggests this deglacial sequence began at approximately 20 000 years BP. On the northernmost Labrador Shelf and Hudson Strait, seismic evidence indicates a late glacial readvance locally deposited a till that overlies the glaciomarine sediments associated with the last glacial advance on the Labrador Shelf. The stratigraphic position of this Hudson Strait till suggests the local readvance occurred at approximately 8000 years BP. The acoustic stratigraphic framework (data) is ground truthed by a regionally extensive piston core and grab sample network. Multidisciplinary analysis of these sediment samples included X-ray, textural, geotechnical, paleontological, lithological, trace-element, and 14C analyses. The results confirm the acoustic interpretations and show that each of the stratigraphic units defined have unique and regionally consistent properties. Geotechnical analyses from the upper till indicate low shear strengths (± 25 kPa) and low to normal consolidation ratios (0.8–2.8), which we interpret to indicate deposition under low basal loading as a result of hydrostatic support on an ice shelf in a marine setting. Provenance studies on the sands and gravels from each of the stratigraphic units of the last deglacial sequence (i.e., till, glaciomarine silts, postglacial muds) indicate that the till is mostly derived from mainland Labrador and transported by an easterly ice flow. Since limestone outcrops are rare to absent on the Labrador mainland and continental shelf, high limestone concentrations (up to 80%) within the glaciomarine sediments that overlie the upper till indicate a northern and distal source for that unit. We interpret an active ice margin overlying the Paleozoic limestone outcrops in Hudson Strait and Ungava Bay as being the dominant source for the glaciomarine silts. The absence of limestone within the postglacial muds that overlie the glaciomarine silts indicates a significant change in provenance, which we attribute to the disappearance of the active ice margin over the limestone terranes. The depositional style and sedimentary structures within the glaciomarine silts indicate low bottom currents and a uniform rain out of ice-rafted (limestone) debris that extends to the southernmost part of the Labrador Shelf. The depositional style of the postglacial muds indicates a significant increase in bottom currents, with deposition restricted to the deep basins. We suggest these increased currents resulted from the disappearance of the Hudson Strait ice barrier, which allowed the Canadian current to develop and combine with the west Greenland current. This combination of currents occurred at approximately 8000 years BP and marks the inception of the Labrador current, which presently traverses the Labrador Shelf.
33
Kujansuu, R. "Palaeosols as Quaternary stratigraphic key horizons in Ostrobothnia, western Finland". Bulletin of the Geological Society of Finland 64, n. 2 (dicembre 1992): 161–67. http://dx.doi.org/10.17741/bgsf/64.2.004.
Testo completo
34
Kosters, Elisabeth C., Bart E. J. M. VanMierlo, Nico H. Verbeek, Bart J. Posthumus, Thomas M. McGee e Jan Brouwer. "Late Quaternary stratigraphic signature, offshore from the Dutch barrier shoreline". Sedimentary Geology 80, n. 3-4 (ottobre 1992): 199–212. http://dx.doi.org/10.1016/0037-0738(92)90041-o.
Testo completo
35
Arroyo-Cabrales, Joaquin, Eileen Johnson e J. Alberto Cruz. "San Josecito Cave and Its Paleoecological Contributions for Quaternary Studies in Mexico". Quaternary 4, n. 4 (26 ottobre 2021): 34. http://dx.doi.org/10.3390/quat4040034.
Testo completoAbstract (sommario):
San Josecito Cave (2250 m elevation) is located nearby Aramberri, Nuevo León, northeastern Mexico, with excavations occurring in 1935–1941 and 1990. It is a paleontological cave and the significance of its faunal data rests in the understanding of the Quaternary ecosystems of the Mexican Plateau and the Southern Plains. This significance is underpinned by a consideration of associated stratigraphic and geochronological data. The fauna is composed of mollusks, amphibians, reptiles, birds, and mammals. More than 30 extinct vertebrate species have been identified, constituting one of the most important Quaternary localities in the Americas. Radiocarbon dates and faunal correlations indicate the excavated deposits represent an interval of time between 45,000 and 11,000 14C years BP. The current synthesis demonstrates that the previous view of the assemblage as a single local fauna is erroneous and that, instead, several successive local faunas are present within a stratigraphic framework. This finding underscores the need for detailed studies of single localities in building paleoenvironmental models. As a corollary, results point to the necessity of including all vertebrate classes represented from a locality in building those models. In addition, the field and analytical methodologies demonstrate the importance of very detailed paleontological excavations, with precise spatial and temporal controls, to assess the taphonomic history of a locality, construct a stratigraphic and geochronological framework, and infer the paleoecological conditions during the time span considered based on the number of local faunas represented. The recognition of San Josecito Cave as an important Late Pleistocene vertebrate paleontological locality is enhanced with the consideration of its faunal data for paleoenvironment reconstruction and possible contribution to Quaternary paleoclimatic modeling.
36
Rull, Valentí. "What If the ‘Anthropocene’ Is Not Formalized as a New Geological Series/Epoch?" Quaternary 1, n. 3 (19 ottobre 2018): 24. http://dx.doi.org/10.3390/quat1030024.
Testo completoAbstract (sommario):
In the coming years, the Anthropocene Working Group (AWG) will submit its proposal on the ‘Anthropocene’ to the Subcommission of Quaternary Stratigraphy (SQS) and the International Commission on Stratigraphy (ICS) for approval. If approved, the proposal will be sent to the Executive Committee of the International Union of Geological Sciences (IUGS) for ratification. If the proposal is approved and ratified, then the ‘Anthropocene’ will be formalized. Currently, the ‘Anthropocene’ is a broadly used term and concept in a wide range of scientific and non-scientific situations, and, for many, the official acceptance of this term is only a matter of time. However, the AWG proposal, in its present state, seems to not fully meet the requirements for a new chronostratigraphic unit. This essay asks what could happen if the current ‘Anthropocene’ proposal is not formalized by the ICS/IUGS. The possible stratigraphic alternatives are evaluated on the basis of the more recent literature and the personal opinions of distinguished AWG, SQS, and ICS members. The eventual impact on environmental sciences and on non-scientific sectors, where the ‘Anthropocene’ seems already firmly rooted and de facto accepted as a new geological epoch, are also discussed. This essay is intended as the editorial introduction to a Quaternary special issue on the topic.
37
Amos, Salvador. "A stable Cenozoic geologic time scale is indispensable". GeoArabia 11, n. 4 (1 ottobre 2006): 155–57. http://dx.doi.org/10.2113/geoarabia1104155.
Testo completoAbstract (sommario):
A stable, standard geologic time scale is indispensable for the clear and precise communication among geologists; it is a basic tool of geologic work. Considerable progress has been made to achieve such a stable time scale. However, during the last few years several proposals have been made to modify the Cenozoic section of the geologic time scale that threaten to destabilize it. Seven articles published in Episodes since 2000 that could contribute to this destabilization are discussed. They provide excellent examples of the profusion of different terminologies, hierarchies, and stratigraphic relationships that have been proposed: to eliminate the Tertiary and the Quaternary or to raise their rank to suberathems; to extend the Neogene to the present, to make the Quaternary a formal subsystem of the Neogene, or consider it an informal stratigraphic unit; to eliminate the Holocene, and to decouple the base of the Pleistocene from the base of the Quaternary. If adopted, these proposals would cause nothing but great confusion and controversy. They disregard the clear preferences of geologists the world over as reflected by the terminology they have been using for many decades. Common sense would dictate the continued use of this terminology in its current, widely accepted form.
38
Rossetti, Dilce F. "Tectonic control on the stratigraphic framework of Late Pleistocene and Holocene deposits in Marajó Island, State of Pará, eastern Amazonia". Anais da Academia Brasileira de Ciências 82, n. 2 (giugno 2010): 439–49. http://dx.doi.org/10.1590/s0001-37652010000200020.
Testo completoAbstract (sommario):
The traditional view that the Brazilian Amazonia is located in a tectonically stable area since the Cretaceous is changing in front of the increasing documentation of fault reactivations even during the Holocene. How the sedimentary record has responded to these events is an issue that remains to be approached with basis on field data. This work focuses on the stratigraphic correlation of late Quaternary deposits from eastern Marajó Island, with the goal of demonstrating the role of fault reactivation on the origin and preservation of these deposits. Despite the location in a stable platform of a continental passive margin, three studied stratigraphic units display significant vertical offsets that define two depocenters that are better explained through tectonic displacements. This interpretation is reinforced by several morphostructural features related to faults that occur between the studied drills. Without the influence of tectonics, sediment preservation in this characteristically low-lying terrain would have been negligible. The results of the present work motivate to look for other tectonically-influenced areas in Amazonia, which similarly might have acted as sites for sediment accommodation during the late Quaternary. These sedimentary records have great potential to be the source of valuable information for reconstructing Quaternary geological events in Northern Brazil.
39
Iannace, Pietro, Maurizio M. Torrente e Alfonsa Milia. "Tectono-stratigraphic evolution of the Southern Campania Margin: a key area for the evolution of the Tyrrhenian-Apennine system". Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles 73 (2018): 39. http://dx.doi.org/10.2516/ogst/2018035.
Testo completoAbstract (sommario):
The Southern Campania Margin (SCM) represents a key area of the Central Mediterranean because it records all the rifting stages of the Tyrrhenian Sea. The interpretation of a seismic dataset calibrated with deep wells and outcrops, using seismic stratigraphy and structural geology methods in a dedicated Geographic Information System (GIS) environment, the seismic depth conversion, the generation of 2-D and 3-D models led to the reconstruction of a polyphased tectono-stratigraphic evolution of the SCM. During the early stage of Tyrrhenian opening a terrigenous transtensional Basin (Langhian-Tortonian Cilento Basin) formed on the Liguride accretionary prism adjacent to the Calabria crystalline terrane. In the SCM the Liguride thrust sheets tectonically overly the Apennine Platform units and both these nappes have been dismembered by Quaternary faults. Three rifting stages, not homogeneously distributed, affected the region since the Lower Pleistocene. They are associated to the deposition of a thick Quaternary succession (A, B and C units). During these Pleistocene stages there was an abrupt change of the extension direction (from NE-SW to NW-SE) accompanying a change of the nappe transport direction of the Southern Apennines. The construction of balanced sections using dedicated software, permitted us to recognize the true geometry of the faults and compute the amount of Quaternary extension of the SCM that results comparable to those calculated for other sectors of the Tyrrhenian margin and further extensional regions worldwide.
40
Veklych, Yu. "Map of Quaternary formations of Ukraine in scale 1:2,500,000". Journal of Geology, Geography and Geoecology 28, n. 2 (6 luglio 2019): 367–76. http://dx.doi.org/10.15421/111935.
Testo completoAbstract (sommario):
The article announces a new map of Quaternary formations on the territory of Ukraine on the scale 1:2,500,000. It considers the prerequisites for the preparation of this map and summarises more than a century of historical research and mapping of the Quaternary formations on the territory of Ukraine. Due to the continuity of scientific research, an extremely developed theoretical and methodological basis of both research and mapping of Quaternary formations has been formed in the country. This is also due to the extraordinary diversity of the geological structure of the Quaternary cover, due to the presence of two mountain systems, lowland areas (including within them several deflections and two crystalline foundations), as well as due to the presence of two seas (including the continental shelf, slope and deep-water zone). A very wide spectrum of facies and formations is also listed (including a thick loess-soil cover, facies of two glaciers of different ages, alluvia, estuary, marine shelf, deep-water and etc.). Attention is focused on two important problems of mapping Quaternary cover. The first is related to new views on the origin of the subaerial cover. The significance of the new (geo-eolian) factor is disclosed, which determined both the thickness and lithological properties of the strata of each paleogeographic stage (of climatoliths) of each separate section, and the stratigraphic structure of the loess-soil cover. Spatial patterns of the structure of the subaerial cover are briefly described, in particular, the mosaic division into areas with a homogeneous stratigraphic structure (type-sections), due to the corresponding geo-eolian mode (sequence). The second problem concerns the ways of visualization of the geological structure of Quaternary sediments on the map. Two principles of reflection of the Quaternary cover are considered, and the disadvantages and advantages of each of them are indicated. Promising ways to map the Quaternary subaerial cover on the basis of ideas about its mosaic structure are proposed. A solution to the problem of various principles of visualization of the Quaternary cover is recommended involving compilation of «multi-visual» maps based on their interactive reissuing (re-design) with modern geographic information systems in accordance with various principles of visualization of the structure of the Quaternary. It has been proposed to use the above scientific approaches in the mapping of the Quaternary deposits of Europe and the World, and also to take into account the geo-eolian factor in the studies of the subaerial cover.
41
Hambach, Ulrich, Christian Rolf e Elisabeth Schnepp. "Magnetic dating of Quaternary sediments, volcanites and archaeological materials: an overview". E&G Quaternary Science Journal 57, n. 1/2 (1 agosto 2008): 25–51. http://dx.doi.org/10.3285/eg.57.1-2.2.
Testo completoAbstract (sommario):
Abstract. Magnetic dating includes all approaches dealing with the temporal variation of the Earth’s magnetic field (EMF) as well as with the application of climate dependent variations of rock magnetic properties of sedimentary sequences and their correlation to independently dated palaeoclimatic archives. Palaeomagnetism has an outstanding impact on geosciences in general and especially on Quaternary chronology and palaeoclimate research. Palaeomagnetic dating employs the temporal variation of the direction as well as the intensity of the EMF on time scales from 102 to 107 years. The well-known temporal pattern of reversals of the EMF on time scales from 104 to 107 years and the shorter secular variation (amplitude 10-30°, time scale 1 to 103 years) provide an excellent tool for stratigraphic subdivisions. Records of the intensity variations of the EMF as well as the indirect dating by means of correlating rock magnetic property variations from sedimentary archives to dated palaeoclimatic records also serve as dating tools. Field methods as well as laboratory methods and techniques in data analysis will not be discussed in this paper. It is our aim to give a short and subjective overview on palaeomagnetism and magnetic susceptibility stratigraphy as dating tools in Quaternary science.
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Munsterman, D. K., R. M. C. H. Verreussel, H. F. Mijnlieff, N. Witmans, S. Kerstholt-Boegehold e O. A. Abbink. "Revision and update of the Callovian-Ryazanian Stratigraphic Nomenclature in the northern Dutch offshore, i.e. Central Graben Subgroup and Scruff Group". Netherlands Journal of Geosciences - Geologie en Mijnbouw 91, n. 4 (dicembre 2012): 555–90. http://dx.doi.org/10.1017/s001677460000038x.
Testo completoAbstract (sommario):
AbstractExploration in a mature basin requires a detailed classification and standardisation of rock stratigraphy to adequately comprehend the depositional history and prospect architecture. The pre-Quaternary Stratigraphic Nomenclature of the Netherlands compiled by Van Adrichem Boogaert & Kouwe in 1993 provided a consistent framework for use by the Dutch geological community. Over the past twenty years, new biostratigraphic techniques and continued exploration in the Netherlands have provided additional stratigraphic information. Based on this information the Late Jurassic lithostratigraphy in particular, shows significant inaccuracies. The Callovian-Ryazanian strata from the northern offshore of the Netherlands' territorial waters, termed the Central Graben Subgroup and Scruff Group, reveal a complex sedimentary history. The combination of non-marine to shallow marine lateral facies changes, repetitive log and facies characteristics in time, sea-level and climate change, salt tectonics and structural compartmentalisation hamper straightforward seismic interpretation and log correlation. Recognition of three genetic sequences by Abbink et al. in 2006 enabled an improved reconstruction of the geological history. Further improvements in refinement and reliability of the stratigraphy together with new information on the facies and ages of the successions and about the subsequent tectonostratigraphic development of the northern Dutch offshore area form the basis of the present revision. As a result, earlier lithostratigraphic models have been changed and new lithostratigraphic relationships and names are introduced in this paper.
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Rahimzadeh, Neda, Tobias Sprafke, Christine Thiel, Birgit Terhorst e Manfred Frechen. "A comparison of polymineral and K-feldspar post-infrared infrared stimulated luminescence ages of loess from Franconia, southern Germany". E&G Quaternary Science Journal 70, n. 1 (8 febbraio 2021): 53–71. http://dx.doi.org/10.5194/egqsj-70-53-2021.
Testo completoAbstract (sommario):
Abstract. Loess-paleosol sequences (LPSs) are essential records for reconstructing Quaternary paleoenvironments. No previous study has provided numerical chronologies of loess in Lower Franconia, southern Germany; their chronostratigraphic assumptions have relied mainly on German (pedo)stratigraphic schemes. In this study, we provide for the first time a chronology for LPSs in Lower Franconia based on optically stimulated luminescence (OSL) dating using quartz and a comparison of K-feldspar (63–100 µm) and the polymineral fraction (4–11 µm). Our results show that all obtained ages are in stratigraphic order, ranging from Holocene to late Pleistocene, and in general confirm the former stratigraphical interpretations. A good agreement of the obtained ages is observed between both feldspar grain size fractions; they also agree well with the quartz OSL ages up to ∼50 ka. However, a marked difference between the growth pattern of the dose response curves and consequently different saturation characteristics of fine and coarse grains is found. Even though in our samples the discrepancy in ages is not very significant, we suggest the use of coarse-grained K-feldspar whenever possible in order to not be confronted with unknowns such as the mineral composition of the polymineral fraction.
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Busacca, Alan J., Kevin T. Nelstead, Eric V. McDonald e Michael D. Purser. "Correlation of Distal Tephra Layers in Loess in the Channeled Scabland and Palouse of Washington state". Quaternary Research 37, n. 3 (maggio 1992): 281–303. http://dx.doi.org/10.1016/0033-5894(92)90067-s.
Testo completoAbstract (sommario):
AbstractThirty-two distal tephra layers that are interbedded in Quaternary loess at 13 sites in the Channeled Scabland and Palouse were sampled as part of a regional study of the stratigraphy and chronology of dominantly windblown sediments on the Columbia Plateau. An electron microprobe was used to determine the elemental composition of volcanic glass in all of the samples and also to determine the composition of ilmenite in 14 of them. Two of the distal tephra layers correlate with Glacier Peak eruptions (11,200 yr B.P.), five with Mount St. Helens tephra set S (13,000 yr B.P.), and nine with Mount St. Helens tephra set C (ca. 36,000 yr B.P.) based on analysis of glass and ilmenite in reference pumices from Glacier Peak, Mount St. Helens, Mount Mazama, Mount Rainier, and Mount Jefferson, on the calculation of similarity coefficients for comparisons of both glass and ilmenite reference compositions with those of distal tephras, and on considerations of stratigraphic position. The composition of glass and ilmenite and the stratigraphic position of one distal tephra layer in the loess suggests that it is from an eruption of Mount St. Helens at least several thousand years older than the set C eruptions. Glass composition and stratigraphic position of a distal tephra at another site in loess suggested a possible correlation with some layers of the Pumice Castle eruptive sequence at Mount Mazama (ca. 70,000 yr B.P.), but similarity coefficients on ilmenite of only 45 and 48 fail to support the correlation and show why multiple correlation methods should be used. Similarity coefficients higher than 96 for both glass and ilmenite establish a correlation with Mount St. Helens layer Cw for distal layers in two widely separated sites. These layers are in sedimentary successions that are closely associated with giant floods in the Channeled Scabland. The 36,000 yr B.P. radiocarbon age of the Mount St. Helens set C establishes a minimum limiting date for an episode of flooding that predates the widespread late Wisconsin floods. A correlation of distal tephra layers at two other sites in the Scabland and Palouse establishes a chronostratigraphic link to a still-older episode of flooding within the Brunhes Normal Polarity Chron. Six distal tephra layers in pre-late Quaternary loess that are not correlated with known or dated eruptions have compositions and distinctive stratigraphic positions relative to magnetic reversal boundaries that make them key markers for future work.
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Dongol, Gopal M. S. "The stratigraphic significance of vertebrate fossils from the Quaternary deposits of the Kathmandu Basin, Nepal". Newsletters on Stratigraphy 18, n. 1 (28 ottobre 1987): 21–29. http://dx.doi.org/10.1127/nos/18/1987/21.
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Clague, John J. "The Quaternary stratigraphic record of British Columbia—evidence for episodic sedimentation and erosion controlled by glaciation". Canadian Journal of Earth Sciences 23, n. 6 (1 giugno 1986): 885–94. http://dx.doi.org/10.1139/e86-090.
Testo completoAbstract (sommario):
The terrestrial Quaternary stratigraphic record of British Columbia is largely a product of brief depositional events separated by long periods of nondeposition and erosion. Thick, stratified Quaternary sediments are present mainly in valleys and coastal lowlands and accumulated during periods of growth and decay of the Cordilleran Ice Sheet. At glacial maxima, till was deposited over large areas of low and moderate relief. However, at the same time, much of the landscape was eroded by glaciers.Sedimentation has been more restricted and has occurred at lower rates during nonglacial periods than during glaciations. On land, the only important sediment accumulation sites during nonglacials have been lakes, floodplains, and fans. However, large amounts of sediment have accumulated offshore, especially in fjords and basins such as the Strait of Georgia. Because of the restricted aspect of sedimentation during nonglacials, the stratigraphic record of these periods is meagre. In most places, true nonglacial units are thin and discontinuous, or they are absent altogether. Commonly, a nonglacial period is recorded only by an unconformity produced when streams incised valley fills shortly after the end of the preceding glaciation.
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Onnis, Luciano, Roberto Antonio Violante, Ana Osella, Matías De la Vega, Alejandro Tassone e Ernesto López. "Neogene-Quaternary seismic stratigraphy of the Llancanelo Lake Basin, Mendoza, Argentina". Andean Geology 45, n. 1 (14 novembre 2017): 35. http://dx.doi.org/10.5027/andgeov45n1-3026.
Testo completoAbstract (sommario):
A new shallow multichannel seismic survey was carried out in the Llancanelo Lake region (Southern Mendoza Province, Argentina), in order to complete and extend previously surveyed seismic sections. The new seismic data allowed to double the already existing data. The obtained information was correlated with seismic and stratigraphic data from the industry. In this way it was possible to depict the major Neogene-Quaternary sedimentary-volcanic sequences and the regional evolution of a tectonic-volcanic basin located in a key region at the eastern foot of the Andes cordillera. This research is settled on early studies that comprised seismic works reaching depths of 600-700 m as well as geoelectric and electromagnetic surveys reaching the uppermost 80-100 m of the sequences. The obtained results indicate the presence of three major sedimentary units separated by conspicuous seismic horizons SR1, SR2 and SR3, respectively considered as representing the late Mesozoic transition from marine to continental deposition, the beginning of the Cenozoic basaltic volcanism, and the change from dominantly sedimentary to dominantly volcanic processes at the base of the Quaternary. The resulting stratigraphic scheme reveals increasing volcanic (basaltic layers) intercalations with depth that accommodate to the geometry of the depocenter.
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ALIOTTA, SALVADOR, SILVIA S. GINSBERG, DARÍO GIAGANTE, LAURA G. VECCHI e MARTA M. SALVATIERRA. "Seismic Stratigraphy of Pleistocene Deltaic Deposits in Bahía Blanca Estuary, Argentina". Anais da Academia Brasileira de Ciências 86, n. 2 (giugno 2014): 649–62. http://dx.doi.org/10.1590/0001-3765201420130243.
Testo completoAbstract (sommario):
The Bahía Blanca estuary (Argentina) has a morphological configuration resulting from hydrological and sedimentary processes related to Late Quaternary sea level changes. This estuarine system occupies a large coastal plain with a dense net of tidal channels, low-altitude islands and large intertidal flats. Little is known about the sedimentary units of the marine subbottom. Therefore, a stratigraphical analysis of the northern coast of Bahía Blanca estuary was carried out using high resolution seismic (3.5 kHz) in order to: i) define Quaternary sequences, ii) describe sedimentary structures, and iii) determine the paleoenvironmental conditions of sedimentation. The seismic stratigraphic data collected and their correlation with drilling lithological data show five seismic sequences (S1, S2, S3, S4 and S5), of which S1-S2 were found to be associated with a continental paleoenvironment of Miocene-Pleistocene age. Sequences S3 and S4, whose lithology and seismic facies (paleochannel structures and prograding reflection configurations), were defined on these materials, to evidence the development of an ancient deltaic environment which was part of a large Pleistocene drainage system. The S5 sequence was formed during the Holocene transgressive-regressive process and complete the seismostratigraphic column defined in the present study.
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Zellman, Mark S., Dean A. Ostenaa e Morgan P. Brown. "Subsurface Characterization of the Quaternary Active Cheraw Fault in Southeastern Colorado Based on Seismic Imaging". Seismic Record 1, n. 1 (1 aprile 2021): 56–65. http://dx.doi.org/10.1785/0320210016.
Testo completoAbstract (sommario):
Abstract The subsurface structure of the late Quaternary active Cheraw fault is relatively unstudied. Vertical displacement estimates of faulted bedrock horizons, characteristics of bedrock structure (e.g., dip), potential association with dissolution of underlying Permian evaporite strata, and whether or not a postulated northeast extension of the topographic scarp is associated with Quaternary faulting have remained open questions. In this study, we assess six 2D seismic reflection profiles that cross the Cheraw fault scarp, demonstrate how Quaternary normal faulting has reactivated pre-existing structures along the northwest flank of the Las Animas arch, and provide new constraints for seismic hazard characterization. We map the fault to depths of at least 1.5–1.8 km into lower Paleozoic strata in which the continuity of the fault through Permian evaporite indicates that dissolution of those stratigraphic intervals has no role in Quaternary surface faulting. Interpretation of the seismic data reveals an ∼75°±5° northwest-dipping fault with ∼24–30 m vertical displacement of upper Cretaceous strata, which coincides with Quaternary scarps at the surface.
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Bourget, J., S. Zaragosi, M. Rodriguez, M. Fournier, T. Garlan e N. Chamot-Rooke. "Late Quaternary megaturbidites of the Indus Fan: Origin and stratigraphic significance". Marine Geology 336 (febbraio 2013): 10–23. http://dx.doi.org/10.1016/j.margeo.2012.11.011.
Testo completo