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Academic literature on the topic 'Stratigraphic Ordovician'

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Published: 10 December 2022
Last updated: 29 January 2023

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Journal articles on the topic "Stratigraphic Ordovician"

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Sennikov, N. V., O. T. Obut, N. G. Izokh, R. A. Khabibulina, T. A. Shcherbanenko, and T. P. Kipriyanova. "THE REGIONAL STRATIGRAPHIC CHART FOR THE ORDOVICIAN OF TYVA (NEW VERSION)." Geology and mineral resources of Siberia, no. 9c (2021): 37–60. http://dx.doi.org/10.20403/2078-0575-2021-9c-37-60.

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A new version of the Regional stratigraphic chart for the Ordovician of Tyva and explanatory note, compiled in accordance with the Russian Stratigraphic Code, introduce changes, additional and specified data in comparison with the previous (third edition) chart. The Interdepartmental stratigraphic meeting held at Novosibirsk in 1979 approved the old version of the chart and later it was validated by the USSR Interdepartmental Stratigraphic Committee as the official stratigraphic base for all types of the regional geologic activities. Since 1979 meeting, the stages of the Ordovician chart were changed. Volumes of the lower, middle and upper series were also changed. For the present version of the stratigraphic chart the new standard Ordovician stages were used.
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Sennikov, N. V., O. T. Obut, N. G. Izokh, and T. P. Kipriyanova. "THE REGIONAL STRATIGRAPHIC CHART FOR THE ORDOVICIAN OF THE WESTERN SAYAN (NEW VERSION)." Geology and mineral resources of Siberia, no. 9c (2021): 4–14. http://dx.doi.org/10.20403/2078-0575-2021-9c-4-14.

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A new version of the Regional stratigraphic chart for the Ordovician of the Western Sayan and explanatory note, compiled in accordance with the Russian Stratigraphic Code 2006, introduce changes, additional and specified data in comparison with the previous (first edition) chart. The Interdepartmental stratigraphic meeting held at Novosibirsk in 1964 approved the old version of the chart and later it was validated by the USSR Interdepartmental Stratigraphic Committee as the official stratigraphic base for all types of the regional geologic activities. Since 1964 meeting, the stages of the Ordovician chart were changed. Thus, instead of the traditional British stages (Tremadocian, Arenigian, Llanvirnian, Llandeilian, Caradocian, Ashgillian) the following units were adopted by the International Stratigraphic Chart – Tremadocian, Floian, Dapingian, Darriwilian, Sandbian, Katian, Hirnantian. Volumes of the lower, middle and upper series were also changed. For the present version of the stratigraphic chart the new standard Ordovician stages were used.
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Toyos, J. M., and C. Aramburu. "El Ordovícico en el área de Los Barrios de Luna, Cordillera Cantábrica (NW de España)." Trabajos de Geología 34, no. 34 (March 9, 2015): 61. http://dx.doi.org/10.17811/tdg.34.2014.61-96.

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Resumen: El estudio cartográfico y estratigráfico del Ordovícico en el área de Los Barrios de Luna (flanco sur del Sinclinal de Abelgas-Alba), ha permitido reconocer una compleja estratigrafía, con­dicionada por una tectónica sinsedimentaria, probablemente relacionada con el intenso vulcanismo que se observa algo más al este. Se revisa la estratigrafía de la Fm. Barrios, de edad Cámbrico Medio a Tardío en su mayor parte. Se redenomina una unidad estratigráfica informal (capas de El Vento­rrillo), del Ordovícico Temprano?, Medio y Tardío. Se definen formalmente dos formaciones en el Ordovícico Superior-Silúrico basal? (Caliza de La Devesa y Cuarcita de La Serrona), y se precisa la estratigrafía de la unidad informal silúrica capas de Getino. Las costras ferruginosas situadas en la base de las capas de El Ventorrillo y de las capas de Getino se interpretan como originadas por alteración de materiales volcánicos.Palabras clave: Ordovícico, cartografía, estratigrafía, costras ferruginosas, tectónica sinsedimenta­ria, rifting, Cordillera Cantábrica, Macizo Ibérico.Abstract: The mapping and stratigraphic study of the Ordovician rocks in Los Barrios de Luna area (southern limb of Abelgas-Alba Syncline), allowed us to recognize a complex stratigraphy, conditio­ned by a synsedimentary tectonics, probably related to the intense volcanism observed further east. The stratigraphy of the Barrios Fm., mostly Middle to Late Cambrian age, is reviewed. An informal stratigraphic unit (El Ventorrillo beds), of Early?, Middle to Late Ordovician age, is renamed. Two Upper Ordovician-basal Silurian? formations are formally defined (La Devesa Limestone and La Serrona Quartzite), and the stratigraphy of the Silurian informal unit Getino beds is refined. The ferruginous crusts at the base of El Ventorrillo beds and Getino beds are interpreted as a result of alteration of volcanic materials.Key words: Ordovician, cartography, stratigraphy, ferruginous crusts, synsedimentary tectonics, rifting, Cantabrian Mountains, Iberian Massif.
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Zhang, Shunxin, Khusro Mirza, and Christopher R. Barnes. "Upper Ordovician – Upper Silurian conodont biostratigraphy, Devon Island and southern Ellesmere Island, Canadian Arctic Islands, with implications for regional stratigraphy, eustasy, and thermal maturation." Canadian Journal of Earth Sciences 53, no. 9 (September 2016): 931–49. http://dx.doi.org/10.1139/cjes-2016-0002.

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The conodont biostratigraphy for the Upper Ordovician – Upper Silurian carbonate shelf (Irene Bay and Allen Bay formations) and interfingering basinal (Cape Phillips Formation) facies is established for parts of Devon and Ellesmere islands, central Canadian Arctic Islands. Revisions to the interpreted regional stratigraphic relationships and correlations are based on the stratigraphic distribution of the 51 conodont species representing 32 genera, identified from over 5000 well-preserved conodonts recovered from 101 productive samples in nine stratigraphic sections. The six zones recognized are, in ascending order, Amorphognathus ordovicicus Local-Range Zone, Aspelundia fluegeli Interval Zone, Pterospathodus celloni Local-Range Zone, Pt. pennatus procerus Local-Range Zone, Kockelella patula Local-Range Zone, and K. variabilis variabilis – Ozarkodina confluens Concurrent-Range Zone. These provided a more precise dating of the members and formations and, in particular, the range of hiatuses within this stratigraphic succession. The pattern of regional stratigraphy, facies changes, and hiatuses is interpreted as primarily related to the effects of glacioeustasy associated with the terminal Ordovician glaciation and smaller Early Silurian glacial phases, the backstepping of the Silurian shelf margin, and the geodynamic effects of the collision with Laurentia by Baltica to the east and Pearya to the north. Conodont colour alteration index values (CAI 1–6.5) from the nine sections complement earlier graptolite reflectance data in providing regional thermal maturation data of value in hydrocarbon exploration assessments.
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Normore, Leon, Peter W. Haines, Lidena K. Carr, Paul Henson, Yijie Zhan, Michael T. D. Wingate, Yong Yi Zhen, et al. "Barnicarndy Graben, southern Canning Basin: stratigraphy defined by the Barnicarndy 1 stratigraphic well." APPEA Journal 61, no. 1 (2021): 224. http://dx.doi.org/10.1071/aj20160.

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Funded by Geoscience Australia’s Exploring for the Future initiative and operated by the Geological Survey of Western Australia, the Waukarlycarly 1 deep stratigraphic drillhole was designed to investigate the geology of the little-known Waukarlycarly Embayment and assess the petroleum, mineral, groundwater and CO2 storage potential of the area. Based on consultation with the Western Desert Lands Aboriginal Corporation on the cultural significance of the name, Waukarlycarly, it has been agreed to change the name of the well to Barnicarndy 1 and the tectonic subdivision to the Barnicarndy Graben. This and all future publications will now refer to the Barnicarndy 1 stratigraphic drillhole (previously Waukarlycarly 1) and the Barnicarndy Graben (previously Waukarlycarly Embayment). Drilling commenced on 1 September 2019 and reached a total depth (TD) of 2680.53m on 30 November 2019, recovering more than 2km of continuous core. The cored interval extended from 580m to TD in Neoproterozoic Yeneena Basin dolostone, which was unconformably overlain by a thick, lower Canning Basin Ordovician stratigraphy, including richly fossiliferous marine mudstones with common volcanic ash beds. A major unconformity is located at the top of the Ordovician section where it is overlain by sandstones and muddy diamictites of the Carboniferous–Permian Grant Group, followed by a Cenozoic succession near surface. Ditch cuttings were collected from surface to 580m at 3m intervals. The pre-Grant Group Paleozoic succession is unique within the Canning Basin, indicating that the Barnicarndy Graben’s depositional history is markedly different when compared with adjacent structural subdivisions, such as the Munro Arch and Kidson Sub-basin. Detrital zircon geochronology, biostratigraphy and borehole imaging interpretation assisted in the definition of two new geological units within the Ordovician stratigraphy of Barnicarndy 1: the Yapukarninjarra and Barnicarndy formations. Preliminary routine core analysis data indicates the potential for CO2 storage within the Barnicarndy Formation beneath a Grant Group seal. The well also provides new insights into the structural interpretation of the Barnicarndy Graben.
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Deline, Bradley, and William I. Ausich. "Testing the plateau: a reexamination of disparity and morphologic constraints in early Paleozoic crinoids." Paleobiology 37, no. 2 (2011): 214–36. http://dx.doi.org/10.1666/09063.1.

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Studies of crinoid morphology have been pivotal in understanding the constraints on the range of morphology within a clade as well as the patterns of disparity throughout the Phanerozoic. Newly discovered and described faunas and recent study of early Paleozoic crinoid diversity provide an ideal opportunity to reanalyze Ordovician through Early Silurian crinoid disparity with more complete taxonomic coverage and finer stratigraphic resolution. Using the coarse stratigraphic binning of Foote (1999), the updated morphologic data set has a similar disparity pattern to those previously reported for the early Paleozoic. However, with the more resolved stratigraphic binning used by Peters and Ausich (2008), a significant difference exists between the original and current data sets. Both data sets have a pronounced disparity high during the late Middle Ordovician. However, the updated disparity curve has a much higher initial disparity during the Early Ordovician and a pronounced rise in disparity during the Silurian recovery. Examination of differential sampling, proportions of the crinoid orders through time, and methods of coding characters indicate these factors have little effect on the pattern of crinoid disparity. The Silurian morphospace expansion occurs primarily within disparids and coincides with the origination of the myelodactylids. These findings corroborate the rapid expansion of morphospace during the Ordovician. However, crinoid disparity did not remain static and, although less frequent than during the initial radiation, new body plans evolved following the Ordovician Extinction (e.g., the myelodactylids). These results are consistent with the hypothesis of ecology constraining the limits on morphologic disparity at the class level.
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Moreau, Julien, and Jean-Bernard Joubert. "Glacial sedimentology interpretation from borehole image log: Example from the Late Ordovician deposits, Murzuq Basin (Libya)." Interpretation 4, no. 2 (May 1, 2016): B1—B16. http://dx.doi.org/10.1190/int-2015-0161.1.

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In the Murzuq Basin, the Late Ordovician glaciogenic succession forms a very complex clastic reservoir system. Although the structural setting is simple, the architecture of the stratigraphic succession is particularly intricate, and conventional wireline logs display rather homogeneous signatures. However, when exposed, the glaciogenic sedimentary succession indicates a very large range of depositional environments and clear stratigraphic changes. Based on high-quality processing and interpretation of wireline microresistivity image logs over a single well, our method allows the precise recognition of the internal sedimentary structures and supports the interpretation of the depositional environments within the Late Ordovician succession. During interpretation, it is possible to draw a descriptive sedimentological log, similar to a standard log from cores or outcrops. The image log is interpreted like a regular sedimentary log and compared to an outcrop analog from the nearby outcrop area of Ghat. The success of the well analysis resides in the quality of the borehole image log, permitting the recognition of sandstone grain sizes, textures (facies), and sorting. In addition, crucial information is extracted from the identification of glacial surface and ice-flow orientations, which, combined with the recognition of major transgressive events, allows the recognition and correlation of glacial-type stratigraphy. As in the modern Pleistocene glaciation, stadial/interstadial and glacial/interglacial stages are identified from resistivity imaging of the Libyan Ordovician succession. In addition to the unprecedented potential of correlation between wells within the basin, the sedimentary information extracted from the borehole image log provides important insights on the paleogeographic context of the basin and thus on the exploration potential of the prolific Ordovician-Silurian petroleum system.
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BERGSTRÖM, STIG M., CHEN XU, BIRGER SCHMITZ, SETH YOUNG, RONG JIA-YU, and MATTHEW R. SALTZMAN. "First documentation of the Ordovician Guttenberg δ13C excursion (GICE) in Asia: chemostratigraphy of the Pagoda and Yanwashan formations in southeastern China." Geological Magazine 146, no. 1 (November 5, 2008): 1–11. http://dx.doi.org/10.1017/s0016756808005748.

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AbstractThe only published δ13C data from the Ordovician of China are from the Lower and Upper Ordovician, and only the latter records include a significant excursion, namely the Hirnantian excursion (HICE). Our recent chemostratigraphic work on the Upper Ordovician (Sandbian–Katian) Pagoda and Yanwashan formations at several localities on the Yangtze Platform and Chiangnan (Jiangnan) slope belt has resulted in the recognition of a positive δ13C excursion that has values of ~+1.5‰ above baseline values. This excursion starts a few metres above a stratigraphic interval withB. alobatusSubzone conodonts as well as graptolites of theN. gracilisZone. The distinctive conodontsAmorphognathusaff.Am. ventilatusandHamarodus europaeusfirst occur at, or very near, the excursion interval. Because these conodonts appear in the stratigraphic interval of the Guttenberg δ13C excursion (GICE) in Estonia, we identify the Chinese excursion as the GICE. This is the first record of the GICE in the entire Asian continent. It confirms that GICE is a global excursion and provides an illustration of how δ13C chemostratigraphy, combined with new biostratigraphic data, solves the problem of the previously controversial age of the Pagoda Formation and how this classical stratigraphic unit correlates with the Baltoscandian and North American successions.
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Zuykov, Michael, David A. T. Harper, and Emilien Pelletier. "Revision of the Ordovician brachiopod genus Noetlingia Hall and Clarke, 1893." Journal of Paleontology 85, no. 3 (May 2011): 595–98. http://dx.doi.org/10.1666/10-060.1.

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The enigmatic pentameride brachiopod Noetlingia Hall and Clarke, 1893 is revised and its stratigraphic range corrected. The type species Noetlingia tscheffkini occurs only within the upper Darriwilian (Ordovician) of the East Baltic and not in the Silurian as previously assumed. Thus, presently defined, the superfamily Porambonitoidea does not cross the boundary between the Ordovician and Silurian systems. Two other species occurring in the Lower to Middle Ordovician of South China and North America are assigned to Noetlingia.
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Ausich, William I., and Mario E. Cournoyer. "New taxa and revised stratigraphic distribution of the crinoid fauna from Anticosti Island, Québec, Canada (Late Ordovician-early Silurian)." Journal of Paleontology 93, no. 06 (May 31, 2019): 1137–58. http://dx.doi.org/10.1017/jpa.2019.36.

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AbstractEnd-Ordovician extinctions had a profound effect on shallow-water benthic communities, including the Crinoidea. Further, recovery after the extinctions resulted in a macroevolutionary turnover in crinoid faunas. Anticosti Island is the most complete Ordovician-Silurian boundary section recording shallow-water habitats. Both new taxa and changes in Anticosti Island stratigraphic nomenclature are addressed herein. New taxa includeBecsciecrinus groulxin. sp.,Bucucrinus isotaloin. sp.,Jovacrinus clarkin. sp.,Plicodendrocrinus petrykin. sp.,Plicodendrocrinus martinin. sp.,Thalamocrinus daoustaen. sp., andLateranicrinus saintlaurentin. gen. n. sp. The status ofXenocrinus rubusas a boundary-crossing taxon is confirmed, range extensions of several taxa are documented, and the distribution of crinoids with the revised stratigraphic nomenclature is documented.UUID:http://zoobank.org/19613a44-ec69-47d7-88ab-fcf88ba771f0.
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Dissertations / Theses on the topic "Stratigraphic Ordovician"

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Dresbach, Russell Ivan. "Early ordovician conodonts and biostratigraphy of the Arbuckle group in Oklahoma /." free to MU campus, to others for purchase, 1998. http://wwwlib.umi.com/cr/mo/fullcit?p9901233.

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Krueger, Diane M. "Conodont biostratigraphy of middle and upper Ordovician rocks in the Ouachita Mountains of Arkansas and Oklahoma /." free to MU campus, to others for purchase, 2002. http://wwwlib.umi.com/cr/mo/fullcit?p3052190.

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Quintavalle, Marco. "Lower to Middle Ordovician palynomorphs of the Canning Basin, Western Australia /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18370.pdf.

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Montañez, Isabel Patricia. "Regional dolomitization of Early Ordovician, Upper Knox Group, Appalachians." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54248.

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The Early Ordovician, Upper Knox Group consists of meter-scale shallowing-upward cycles that were deposited on a low-sloping ramp. Cycles formed in response to short term (<100 k.y.) eustatic sea-level fluctuations and typically have well developed tidal flat caps. Cycles are bundled into five transgressive-regressive sequences which correspond to third order (1-10 m.y.) sea-level fluctuations defined by Fischer plots. The Upper Knox Group is 90% dolomite of which greater than 75% predates Middle Ordovician, Knox Unconformity development. Early dolomitization occurred penecontemporaneously with tidal flat progradation during fifth-order (up to 100 k.y.) sea-level falls as indicated by: abundant dolomite in cycles with well-developed tidal flat caps and scarce dolomite in cycles with no or thin laminite caps; decrease in dolomite abundance with distance below tidal flat caps; dolomitized cycles decrease basinward; and dolomite clasts veneer cycle tops and the Knox Unconformity surface. Third-order sea-level fluctuations also strongly controlled early dolomitization as indicated by Fischer plots; limestone, subtidal-dominated cycles correspond to third-order sea level rises and completely dolomitized, peritidal-dominated cycles correspond to third-order sea level falls. "Early" dolomite was metastable and its geochemical composition was modified during initial stabilization by marine brines during progradation of each cycle, and by mixed fresh/marine waters of the Knox aquifer associated with unconformity development. Much "early" dolomite however, remained metastable into the deep burial environment where it was replaced and overgrown by burial fluids as suggested by: covariant trends between crystal size, mole % CaCO₃, Sr²⁺, Mn²⁺ and δ¹⁸O; similar regional trends defined by stable isotope values of "early" dolomites and burial dolomites; and water-rock modeling of trace element and stable isotopic trends. Trace element and stable isotope compositions of least-altered "early" dolomite however, record a memory of a precursor evaporative dolomite. Cathodoluminescent dolomite stratigraphy defines five generations of burial dolomite that can be correlated over 100,000 km². Burial dolomites postdate a regional dissolution event attributed to migration of organic acid-rich fluids through the Knox carbonates. Regional dolomitization occurred coeval with Late Paleozoic deformation and was closely associated with MVT mineralization and hydrocarbon migration. The δ¹⁸O values and trace element contents of burial dolomites in conjunction with fluid inclusions, suggest that burial fluids were warm (135 to 200°C), saline (13 to 22 wt. % NaCl equiv.), ¹⁸O-enriched (+2 to +9 % SMOW) fluids with geochemical compositions similar to present day basinal brines. Mn²⁺ and Fe²⁺ contents of the dolomites suggest a redox control over Mn and Fe fluid chemistry, and in conjunction with regional δ¹³C trends, likely record precipitation from organic acid-rich fluids. Regional trace element and δ¹⁸O trends record a basinal fluid source and regional northwestward flow. Stable isotope values of burial dolomites and fluid inclusions from dolomites and associated minerals, define a prograderetrograde sequence that formed during basinwide, gravity-driven fluid flow which developed in response to Late Paleozoic thrusting and uplift.
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Hall, Lindsay Anne Forsyth. "Ordovician tectonic evolution of the southern Long Range Mountains, Newfoundland /." Internet access available to MUN users only, 1998. http://collections.mun.ca/u?/theses,39263.

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MCLAUGHLIN, PATRICK IAN. "LATE ORDOVICIAN SEISMITES OF KENTUCKY AND OHIO: A SEDIMENTOLOGICAL AND SEQUENCE STRATIGRAPHIC APPROACH." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1028144697.

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McLaughlin, Patrick I. "Late Ordovician seismites of Kentucky and Ohio a sedimentological and sequence stratigraphic approach /." Cincinnati, Ohio : University of Cincinnati, 2002. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=ucin1028144697.

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Hogan, John Patrick. "Mineralogical, chemical and isotopic diversity in plutonic rock suites from the Coastal Maine Magmatic Province:the role of source region heterogeneity, tectonic setting and magmatic processes." Diss., Virginia Tech, 1990. http://hdl.handle.net/10919/39074.

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This dissertation represents an investigation of the mid-Paleozoic tectono-thermal and kinematic evolution of the crust in eastern coastal Maine as recorded by the plutonic rocks of this region. The first chapter describes the plutonic rocks of the Coastal Maine Magmatic Province. A tectonic model is developed in which late Ordovician-Silurian bimodal magmatism is interpreted to reflect crustal melting as a result of intraplating of mantle melts at high crustal levels during a period of tension. Large scale melting of lower crustal source regions, represented by voluminous intrusion of Devonian granites, reflects a period of transpression during which upwelling mantle melts were confined to the base of the crust. The diversity of granitic plutons reflects changes in the mineral assemblages present during partial melting, and in some instances, modification as a result of mixing/mingling with mantle melts. The second chapter examines the effect of accessory minerals on the initial Pb isotopic signature of anatectic granites. Their initial Pb isotopic composition reflects (a) the age, type, modal distribution, and heterogeneity in the initial U and Th content of the accessory phase(s) present in the source, (b) variation in melt composition and temperature during partial melting, (c) the fraction of the source melted, and (d) the extent to which the melt is homogenized prior to crystallization. It is shown that granitic plutons derived by crustal anatexis of a common source material are not required to have similar initial lead isotopic compositions. The third chapter presents the results of a Pb isotopic investigation of selected plutonic rocks from the Coastal Maine MagmaticProvince. This study was designed to test and refine petrogenetic models presented in Chapter 1. The Pb isotopic signature of the granitic plutons reveals the presence of two lithologically heterogeneous source regions beneath the Avalon Composite Terrane. The upper crustal source region has an mean V-Pb age of -2.0 Ga and the high 207Pb/204Pb-206Pb/204Pb characteristic of Avalonian crust. The lower crustal source region has an average U-Pb age of -1.3 Ga and lower 207Pb/204Pb. This source region may represent either the autochthonous basement to the Avalon platform or the eastern extension of the basement to the Gander Terrane of central Maine.
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Malhame, Pierre. "Quartz arenites of the uppermost Cambrian-lowermost Ordovician Kamouraska Formation, Québec, Canada : gravity flow deposits of eolian sand in the deep sea." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101868.

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The uppermost Cambrian-Lower Ordovician Kamouraska Formation in the external Humber Zone of the Quebec Appalachians consists of dominant thick massive to graded quartz arenite beds, subordinate pebble conglomerate and intercalated thin shale and siltstone beds. It was deposited by hyperconcentrated to concentrated density flows in a meandering submarine canyon on the continental slope bordering the Iapetus Ocean. Turbidity currents deposited beds with turbidite structure divisions. The sandstones consist of well sorted, well rounded quartz sand with frosted grains. Scanning electron microscopy reveals the presence of textures supporting eolian transport before redeposition in the deep sea. The Kamouraska quartz arenites are considered an ancient equivalent of Pleistocene eolian-sand turbidites on an abyssal plain off West Africa consisting of Sahara sand. Sand provenance is attributed to eolian equivalents of the Cairnside Formation of the Potsdam Group. The quartz arenites of the Kamouraska Formation provide a variant to tectonic sandstone provenance proposed in the scheme of Dickinson and Suczek (1979).
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Baar, Eric Edward. "Determining the regional-scale detrital zircon provenance of the middle-late Ordovician Kinnikinic (Eureka) Quartzite, east-central Idaho, U.S." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Spring2009/e_baar_050609.pdf.

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Thesis (M.S. in geology)--Washington State University, May 2009.
Title from PDF title page (viewed on July 15, 2009). "School of Earth and Environmental Sciences." Includes bibliographical references (p. 76-83).
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Books on the topic "Stratigraphic Ordovician"

1

Foerste, A. F. Upper Ordovician formations in Ontario and Quebec. Ottawa: Govt. Print. Bureau, 1997.

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International Symposium on the Ordovician System (9th 2003 San Juan, Argentina). Ordovician from the Andes. Edited by Albanesi Guillermo L, Beresi Matilde S, Peralta Silvio, Consejo Nacional de Investigaciones Científicas y Técnicas (Argentina), and Universidad Nacional de Tucumán. Instituto Superior de Correlación Geológica. San Miguel de Tucumán: Consejo Nacional de Investigaciones Científicas y Técnicas, 2003.

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Aceñolaza, Florencio G. Aspects of the Ordovician system in Argentina. San Miguel de Tucumán: Consejo Nacional de Investigaciones Científicas y Técnicas, 2002.

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Neathery, Thornton Lee. Lithostratigraphy of Upper Ordovician strata in Alabama. Tuscaloosa, Ala: Geological Survey of Alabama, Geologic Program Division, 1985.

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1937-, Huff Warren D., and Bergström Stig M, eds. Ordovician K-bentonites of eastern North America. Boulder, Colo: Geological Society of America, 1996.

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Conkin, James Elvin. New Ordovician metabentonites from Kentucky and Tennessee. Louisville, KY: Dept. of Geography and Geosciences, University of Louisville [distributor], 1992.

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Williams, Merton Yarwood. The Ordovician rocks of Lake Timiskaming. Ottawa: Govt. Print. Bureau, 1997.

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International Symposium on the Ordovician System (7th 1995 Las Vegas, Nev.). Ordovician odyssey: Short papers for the Seventh International Symposium on the Ordovician System, Las Vegas, Nevada, USA, June 1995. Edited by Cooper John D. 1939-, Droser Mary L, and Finney Stanley C. Fullerton, Calif: Pacific Section Society for Sedimentary Geology (SEPM), 1995.

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Hunda, Brenda. Silicified Late Ordovician trilobites from the Mackenzie Mountains, Northwest Territories, Canada. St. John's, Nfld: Geological Association of Canada, 2003.

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International Symposium on the Ordovician System. (6th 1991 Sydney, Australia). Global perspectives on Ordovician geology: Proceedings of the sixth International symposium on the Ordovician System, University of Sydney, Australian, 15-19 July 1991. Rotterdam: A.A. Balkema, 1992.

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Book chapters on the topic "Stratigraphic Ordovician"

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Traverse, Alfred. "Stratigraphic Palynology–Precambrian, Cambrian, Ordovician." In Paleopalynology, 155–88. Dordrecht: Springer Netherlands, 2007. http://dx.doi.org/10.1007/978-1-4020-5610-9_6.

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Makhlouf, Yamouna, Bertrand Lefebvre, Elise Nardin, Ahmed Nedjari, Serge Régnault, and Mohamed Ferhi. "Stratigraphic and Palaeogeographical Distribution of the Ordovician Eocrinoid Ascocystites Barrande 1887 (Echinodermata, Blastozoa)." In Springer Geology, 1045–48. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-04364-7_199.

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Ryan, P. D., and J. F. Dewey. "Arc–Continent Collision in the Ordovician of Western Ireland: Stratigraphic, Structural and Metamorphic Evolution." In Frontiers in Earth Sciences, 373–401. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-540-88558-0_13.

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Walker, Kenneth R. "Introduction to Tennessee part of field trip and the Paleozoic stratigraphic section at Thornhill, Tennessee." In Cambro-Ordovician Carbonate Banks and Siliciclastic Basins of the United States Appalachians: Knoxville, Tennessee to Hagerstown, Maryland, June 30–July 9, 1989, 1–33. Washington, D. C.: American Geophysical Union, 1989. http://dx.doi.org/10.1029/ft161p0001.

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Frazier, William J., and David R. Schwimmer. "The Sauk Sequence: Ediacarian—Lower Ordovician." In Regional Stratigraphy of North America, 99–134. Boston, MA: Springer US, 1987. http://dx.doi.org/10.1007/978-1-4613-1795-1_4.

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Frazier, William J., and David R. Schwimmer. "The Tippecanoe Sequence: Middle Ordovician—Lower Devonian." In Regional Stratigraphy of North America, 135–201. Boston, MA: Springer US, 1987. http://dx.doi.org/10.1007/978-1-4613-1795-1_5.

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Stait, Bryan, and Clive Burrett. "Biogeography of Australian and Southeast Asian Ordovician Nautiloids." In Gondwana Six: Stratigraphy, Sedimentology, and Paleontology, 21–28. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm041p0021.

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Barnes, Christopher R., Richard A. Fortey, and S. Henry Williams. "The Pattern of Global Bio-Events During the Ordovician Period." In Global Events and Event Stratigraphy in the Phanerozoic, 139–72. Berlin, Heidelberg: Springer Berlin Heidelberg, 1996. http://dx.doi.org/10.1007/978-3-642-79634-0_9.

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Long, D. G. F. "Limits on Late Ordovician Eustatic Sea-Level Change from Carbonate Shelf Sequences: An Example from Anticosti Island, Quebec." In Sequence Stratigraphy and Facies Associations, 487–99. Oxford, UK: Blackwell Publishing Ltd., 2009. http://dx.doi.org/10.1002/9781444304015.ch24.

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Railsback, L. Bruce, Karen M. Layou, Noel A. Heim, Steven M. Holland, M. L. Trogdon, M. B. Jarrett, Gabriel M. Izsak, et al. "Geochemical Evidence for Meteoric Diagenesis and Cryptic Surfaces of Subaerial Exposure in Upper Ordovician Peritidal Carbonates from the Nashville Dome, Central Tennessee, USA." In Linking Diagenesis to Sequence Stratigraphy, 257–69. West Sussex, UK: John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118485347.ch11.

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Conference papers on the topic "Stratigraphic Ordovician"

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Lang, J., R. J. Dixon, D. P. Le Heron, and J. Winsemann. "A Sequence Stratigraphic Model for Ordovician Glacial Deposits, Illizi Basin, Algeria." In 4th EAGE North African/Mediterranean Petroleum and Geosciences Conference and Exhibition Tunis 2009. European Association of Geoscientists & Engineers, 2009. http://dx.doi.org/10.3997/2214-4609.20145779.

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Husinec, Antun. "SEQUENCE STRATIGRAPHIC FRAMEWORK AND CARBON-ISOTOPE STRATIGRAPHY OF THE UPPER ORDOVICIAN LOWER RED RIVER FM., EASTERNMOST WILLISTON BASIN." In GSA Annual Meeting in Denver, Colorado, USA - 2016. Geological Society of America, 2016. http://dx.doi.org/10.1130/abs/2016am-283460.

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Plechacek, Amy, Madeleine Mathews, Sean Scott, Madeline Gotkowitz, and Matthew Ginder-vogel. "ASSESSING RADIUM LEACHING POTENTIAL FROM STRATIGRAPHIC UNITS WITHIN THE MIDWESTERN CAMBRIAN-ORDOVICIAN AQUIFER SYSTEM." In GSA Connects 2021 in Portland, Oregon. Geological Society of America, 2021. http://dx.doi.org/10.1130/abs/2021am-365448.

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Paktovsky, Yuri Germanovich. "The problem of diamond content of the Pomyanennovskaya suite (South Cis-Tyman, Perm Region)." In Проблемы минералогии, петрографии и металлогении. Научные чтения памяти П. Н. Чирвинского. ПЕРМСКИЙ ГОСУДАРСТВЕННЫЙ НАЦИОНАЛЬНЫЙ ИССЛЕДОВАТЕЛЬСКИЙ УНИВЕРСИТЕТ, 2022. http://dx.doi.org/10.17072/chirvinsky.2022.199.

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The polymictic composition of the rocks of the Pomyanennovskaya suite indicates their difference from the quartz rocks of the Upper Ordovician in the South Cis-Tyman, which is the basis of the method of relative «lithochronology» for the «mute» sections of the Early Paleozoic in the region. According to the lithological criterion, the rocks of the Pomyanennovskaya suite can be correctly distinguished from the composition of the Polyudovskaya suite (O3pl) into a local stratigraphic taxon, possibly comparable in age to the Alkesvozhskaya sequence (Є3–O1) of the Northern Urals. The diamond content of the Pomyanennovskaya suite indicates the possibility of the existence of intermediate Precambrian reservoirs in the Urals.
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Al Ramadan, Khalid, Sadoon Morad, and Essam El-Khoriby. "Integrated Diagenesis and Sequence Stratigraphic Study of Tidal Sandstones: the Adedia Formation (Cambro-Ordovician), Sinai, Egypt." In GEO 2010. European Association of Geoscientists & Engineers, 2010. http://dx.doi.org/10.3997/2214-4609-pdb.248.328.

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Scribner, Benjamin. "INTEGRATING SUBSURFACE DATA INTO A SEQUENCE STRATIGRAPHIC FRAMEWORK OF THE ORDOVICIAN BROMIDE FORMATION, SOUTH-CENTRAL OKLAHOMA." In GSA Annual Meeting in Denver, Colorado, USA - 2016. Geological Society of America, 2016. http://dx.doi.org/10.1130/abs/2016am-287721.

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Drummond, Carl, and Benjamin Dattilo. "HIGH RESOLUTION STRATIGRAPHIC AND TEMPORAL ANALYSIS OF DEPOSITION, NON-DEPOSITION, AND EROSION WITHIN THE ORDOVICIAN KOPE FORMATION." In GSA Connects 2022 meeting in Denver, Colorado. Geological Society of America, 2022. http://dx.doi.org/10.1130/abs/2022am-379863.

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Wright, Milly, Guoyan Mu, Shiqian Wang, Bao Liu, Emma Davies, and Navpreet Singh. "Chemostratigraphy and Sequence Stratigraphic Investigation of the Lower Silurian - Upper Ordovician Hot Shale, Southeastern of the Sichuan Basin." In SPE Unconventional Resources Conference and Exhibition-Asia Pacific. Society of Petroleum Engineers, 2013. http://dx.doi.org/10.2118/167022-ms.

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Serafini, G., and E. Trincianti. "Sedimentary Evolution of Late Ordovician Sequence in El-Feel Field – An Example of Integrated Sedimentologic, Stratigraphic and 3D Seismic Data." In 3rd EAGE North African/Mediterranean Petroleum and Geosciences Conference and Exhibition. European Association of Geoscientists & Engineers, 2007. http://dx.doi.org/10.3997/2214-4609.20146483.

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Chernykh, A. V., A. N. Pyrayev, and F. F. Dultsev. "NEW DATA ON THE ISOTOPIC COMPOSITION OF BRINES OF OIL AND GAS DEPOSITS OF THE SIBERIAN PLATFORM." In All-Russian Youth Scientific Conference with the Participation of Foreign Scientists Trofimuk Readings - 2021. Novosibirsk State University, 2021. http://dx.doi.org/10.25205/978-5-4437-1251-2-121-125.

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The new isotope-geochemical data on the Siberian platform supersaturated brines of a wide stratigraphic range (from Riphean to Ordovician) are presented. There is a wide range of oxygen and hydrogen stable isotope composition in the studied brines: from –133 to –17,5 % for δD and from –17,0 to –2,5 % for δ18O. The δD and δ18O values point on the sedimentation-metamorphic genesis of the brines. The carbon isotope composition of the DIC in brines range from –31 to +12,7 %. It is supposed that DIC has the biogenic (bacterial) origin. The youngest brine DIC has the heaviest carbon isotope composition whereas the oldest brine DIC has the biggest concentration of 12C. The strontium ratios of the studied brines divide them into two groups: with 87Sr/86Sr ratios, close to those of the modern ocean waters, and brines with 87Sr/86Sr values significantly exceeding modern ocean strontium ratios. It is assumed that the burial of the brines of the second group took place in the presence of clastic material of the continental crust, with a high content of radioactive 87Rb.
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Reports on the topic "Stratigraphic Ordovician"

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Cecile, M. P., B. S. Norford, G. S. Nowlan, and T. T. Uyeno. Lower Paleozoic stratigraphy and geology, Richardson Mountains, Yukon (with stratigraphic and paleontological appendices). Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329454.

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The Richardson Trough was a rift basin on the southern margin of an ancestral Iapetus Ocean. It was part of a complex paleogeography that included at least two major rift basins on western Franklinian and northern Cordilleran continental shelves. This paleogeography included the Ogilvie Arch, Porcupine Platform, Blackstone 'supra-basin', Babbage Basin, Husky Lakes Arch, Richardson Trough, Mackenzie Arch, Lac des Bois Platform, and the White Mountains and Campbell uplifts. The Richardson Trough was the failed arm of a triple rift system that formed when an early Paleozoic Iapetus Ocean developed north of the trough. The Richardson Trough displays a classic 'steer's head' profile with two rift fill cycles. The first features late early to middle late Cambrian rifting and late late Cambrian to late Early Ordovician post-rift subsidence; the second, late Early Ordovician to early Silurian rifting and late early Silurian to early Middle Devonian post-rift subsidence. Lower Paleozoic strata exposed in the Richardson Trough range in age from middle Cambrian to early Middle Devonian and are similar to strata in their sister rift, the Misty Creek Embayment. Before this study, the stratigraphic units defined for the Richardson Trough were the Slats Creek Formation and the Road River Formation. Here, the Slats Creek Formation and a new Road River Group are recognized. In order, this group consists of the middle and/or late Cambrian to Early Ordovician Cronin Formation; the early Early Ordovician to latest early Silurian Mount Hare Formation; the early Silurian to late Silurian Tetlit Formation; and the late Silurian to early Middle Devonian Vittrekwa Formation. These Road River Group strata are unconformably overlain by the late Middle to Late Devonian Canol Formation (outcrop) and by the Early Devonian Tatsieta Formation (subsurface).
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Dunning, G. R., and T. E. Krogh. Stratigraphic Correlation of the Appalachian Ordovician using Advanced U - Pb Zircon Geochronology Techniques. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1991. http://dx.doi.org/10.4095/132179.

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Armstrong, D. K., M. P. B. Nicolas, K. E. Hahn, and D. Lavoie. Stratigraphic synthesis of the Hudson Platform in Manitoba, Ontario, and Nunavut: Ordovician-Silurian. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2018. http://dx.doi.org/10.4095/308418.

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Norford, B. S. Ordovician and Silurian strata of northeastern British Columbia: stratigraphic sections and synthesis of biostratigraphy. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2017. http://dx.doi.org/10.4095/299866.

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Ettensohn, F. R. Flexural Interpretation of Relationships Between Ordovician Tectonism and Stratigraphic Sequences, Central and southern Appalachians, U.s.a. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1991. http://dx.doi.org/10.4095/132190.

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Lavoie, D. Along-strike Upper Cambrian-Lower Ordovician stratigraphic nomenclature and framework for the external Humber Zone, from Quebec City to Gaspé. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1998. http://dx.doi.org/10.4095/209528.

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Hamblin, A. P. Stratigraphic architecture, sedimentology, and resource potential of the Upper Ordovician Nottawasaga Group of southwestern Ontario, surface and subsurface: tectonics and sequence stratigraphy in the distal Appalachian Foreland. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2018. http://dx.doi.org/10.4095/308160.

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Knight, R. D., and H. A. J. Russell. Quantifying the invisible: pXRF analyses of three boreholes, British Columbia and Ontario. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/331176.

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Portable X-ray fluorescence (pXRF) technology collects geochemical data at a fraction of the cost of traditional laboratory methods. Although the pXRF spectrometer provides concentrations for 41 elements, only a subset of these elements meet the criteria for definitive, quantitative, and qualitative data. However, high-quality pXRF data obtained by correct application of analytical protocols, can provide robust insight to stratigraphy and sediment characteristics that are often not observed by, for example, visual core logging, grain size analysis, and geophysical logging. We present examples of geochemical results obtained from pXRF analysis of drill core samples from three boreholes located in Canada, that demonstrate: 1) Definitive stratigraphic boundaries observed in geochemical changes obtained from 380 analyses collected over 150 m of core, which intersects three Ordovician sedimentary formations and Precambrian granite. These boundaries could not be reconciled by traditional visual core logging methods. 2) Significant elemental concentration changes observed in 120 samples collected in each of two ~120 m deep boreholes located in a confined paleo-glacial foreland basin. The collected geochemical data provide insight to sediment provenance and stratigraphic relationships that were previously unknown. 3) Abrupt changes in the geochemical signature in a subset of 135 samples collected from a 151 m deep borehole intersecting Quaternary glacial derived till, sands, and ahomogeneous silt and clay succession. These data provide a platform for discussion on ice sheet dynamics, changes in depositional setting, and changes in provenance. Results from each of these studies highlights previously unknown (invisible) geological information revealed through geochemical analyses. A significant benefit of using pXRF technology is refining sampling strategies in near real time and the ability to increase sample density at geochemical boundaries with little increase in analysis time or budget. The data also provide an opportunity to establish a chemostratigraphic framework that complements other stratigraphic correlation techniques, including geophysical methods. Overall, data collected with pXRF technology provide new insights into topics such as spatial correlations, facies changes, provenance changes, and depositional environment changes.
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Fallas, K. M., and R. B. MacNaughton. Bedrock mapping and stratigraphic studies in the Mackenzie Mountains, Franklin Mountains, Colville Hills, and adjacent areas of the Northwest Territories, Geo-mapping for Energy and Minerals program 2009-2019. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/326093.

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The Geo-mapping for Energy and Minerals (GEM) program provided an opportunity to update bedrock geological maps for nearly 92 000 km2 of the northwestern portion of the mainland area of the Northwest Territories. Twenty-four new maps (at the scale of 1:100 000 or 1:250 000) cover a region from the Colville Hills southwestward into the Mackenzie Mountains, including areas of significant mineral and energy resource potential. New mapping was informed by archived Geological Survey of Canada data, notably from Operation Norman (1968-1970), as well as by public-domain industry data. Maps incorporate numerous stratigraphic revisions that postdate Operation Norman, including GEM program innovations affecting Neoproterozoic (specifically Tonian and Ediacaran), Cambrian, and Ordovician units. In this paper, the mapping effort and stratigraphic revisions are documented, a preliminary treatment of structural geology is provided, and related subsurface studies are summarized. Following GEM, GIS-enabled bedrock maps will be available for a swath of territory stretching from the edge of the Selwyn Basin, near the Yukon border, to the Brock Inlier in the northeastern portion of the mainland area of the Northwest Territories.
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Mueller, C., S. J. Piercey, M. G. Babechuk, and D. Copeland. Stratigraphy and lithogeochemistry of the Goldenville horizon and associated rocks, Baie Verte Peninsula, Newfoundland. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328990.

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The Goldenville horizon in the Baie Verte Peninsula is an important stratigraphic horizon that hosts primary (Cambrian to Ordovician) exhalative magnetite and pyrite and was a chemical trap for younger (Silurian to Devonian) orogenic gold mineralization. The horizon is overlain by basaltic flows and volcaniclastic rocks, is intercalated with variably coloured argillites and cherts, and underlain by mafic volcaniclastic rocks; the entire stratigraphy is cut by younger fine-grained mafic dykes and coarser gabbro. Lithogeochemical signatures of the Goldenville horizon allow it to be divided into high-Fe iron formation (HIF; &amp;gt;50% Fe2O3), low-Fe iron formation (LIF; 15-50% Fe2O3), and argillite with iron minerals (AIF; &amp;lt;15% Fe2O3). These variably Fe-rich rocks have Fe-Ti-Mn-Al systematics consistent with element derivation from varying mineral contributions from hydrothermal venting and ambient detrital sedimentation. Post-Archean Australian Shale (PAAS)-normalized rare earth element (REE) signatures for the HIF samples have negative Ce anomalies and patterns similar to modern hydrothermal sediment deposited under oxygenated ocean conditions. The PAAS-normalized REE signatures of LIF samples have positive Ce anomalies, similar to hydrothermal sediment deposited under anoxic to sub-oxic conditions. The paradoxical Ce behaviour is potentially explained by the Mn geochemistry of the LIF samples. The LIF have elevated MnO contents (2.0-7.5 weight %), suggesting that Mn from hydrothermal fluids was oxidized in an oxygenated water column during hydrothermal venting, Mn-oxides then scavenged Ce from seawater, and these Mn-oxides were subsequently deposited in the hydrothermal sediment. The Mn-rich LIF samples with positive Ce anomalies are intercalated with HIF with negative Ce anomalies, both regionally and on a metre scale within drill holes. Thus, the LIF positive Ce anomaly signature may record extended and particle-specific scavenging rather than sub-oxic/redox-stratified marine conditions. Collectively, results suggest that the Cambro-Ordovician Taconic seaway along the Laurentian margin may have been completely or near-completely oxygenated at the time of Goldenville horizon deposition.
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