Dissertations / Theses on the topic 'Stratigraphic Pleistocene'
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Queen, Sandra June. "Petrologic characterization and differentiation of Neogene and Pleistocene sediments in the Verdi-Reno Truckee River corridor." abstract and full text PDF (UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1460773.
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Lacy, Stephen L. "The stratigraphy and sedimentation of the pleistocene section of the May Stone and Sand Company, Inc., Ardmore Avenue Quarry, Fort Wayne, Allen County, Indiana." Virtual Press, 1986. http://liblink.bsu.edu/uhtbin/catkey/459230.
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The Pleistocene section exposed in the May Stone and Sand Company, Inc., Ardmore Avenue quarry rests in the upper reaches of the Wabash-Erie Channel. The section consists of two distinct till units which are covered by a thick outwash deposit. Analysis of the tills has led to the assignment of the lower till to the Trafalgar Formation, while the upper till is assigned to the Lagro Formation. The 13- to 16-foot outwash unit shows evidence of rapid drainage which may be related to the catastrophic drainage of glacial Lake Maumee. Isolated mud to muck inclusions in the top eight feet of the section show the final depositional environment of the channel. These deposits were produced near the end of late Wisconsinan time. The last major event in the area was the stream piracy of the St. Joseph and Ste. Mary's Rivers by the Maumee River, in Late Wisconsinan or Recent time.
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Campo, Bruno <1984>. "The Pleistocene-Holocene Transition in the Po Plain (Italy): Stratigraphic Architecture and Sequence Stratigraphy from a Highly-Subsiding Basin." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amsdottorato.unibo.it/7540/.
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This work focuses on the Late Pleistocene-Holocene transition in the southern Po Basin. Five areas were investigated, with the aim of unraveling the role of different allogenic factors (climate, eustacy, sediment supply) on stratigraphic architecture in the last 45 ky. The study starts from the distal portion of the basin (the coastal plain deposits) and then moves towards increasingly internal areas: the alluvial sector characterized by the Po channel belt deposits, and the mud-prone interfluvial succession between the Apenninic margin and the Po channel belt. In the coastal sector, high-resolution facies analysis, along with a well-constrained chronostratigraphic framework, led to the accurate paleoenvironmental reconstruction of the last 45 ky BP depositional history along the 93 km-long transect. It is also provided a sequence stratigraphic interpretation for the whole sedimentary succession. In the Po channel belt sector, based on 28 radiocarbon dates, facies interpretation from high-quality core descriptions and freshly-drilled continuous cores, the contrasting stratigraphic architecture of Late Pleistocene and Holocene deposits was highlighted. Changes in lithofacies and channel stacking patterns reveal the vertical superposition of amalgamated fluvial-channel sands (Late Pleistocene) and mud-dominated deposits (Holocene), with isolated fluvial-channel bodies. We also attempted to establish the link between facies architecture, sea-level fluctuations and climate changes. The 3rd study area (interfuvial succession) was selected to test a new method for paleosol identification, on the basis of geotechnical properties generated from pocket penetrometer values.
Through the reconstruction of the Biferno coastal deposits (4th study area, located ca. 300 km south of the Po Plain) we had the opportunity to document two coeval (Late Pleistocene - Holocene) coastal sedimentary successions, diverging in terms of shelf gradient and proximity to the LGM-lowstand Po Delta. The 5th study area, broadly coincides with Ferrara, was selected to show how high-resolution stratigraphic studies can be used for aquifer protection.
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Korotkikh, Elena. "A High Resolution Record of the Eemian Interglacial and Transition to the Next Glacial Period from Mount Moulton (West Antarctica)." Fogler Library, University of Maine, 2009. http://www.library.umaine.edu/theses/pdf/KorotkikhE2009.pdf.
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Heine, Jan T. "Glacier advances at the Pleistocene/Holocene transition near Mount Rainier volcano, Cascade Range, USA /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/6748.
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Andrews, William M. "Geologic controls on plio-pleistocene draining evolution of the Kentucky river in central Kentucky." Lexington, Ky. : [University of Kentucky Libraries], 2004. http://lib.uky.edu/ETD/ukygeol2004d00169/wmandrews.pdf.
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Thesis (Ph. D.)--University of Kentucky, 2004.Title from document title page (October 12, 2004). Document formatted into pages; contains xi, 216 p. : ill., maps. Includes abstract and vita. Includes bibliographical references (p. 202-212).
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Rathburn, Sara L. "Pleistocene glacial outburst flooding along the Big Lost River, east-central Idaho." Thesis, The University of Arizona, 1989. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_etd_hy0127_sip1_w.pdf&type=application/pdf.
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Kushner, Vaughn A. "STRATIGRAPHIC CORRELATION OF LATE PLEISTOCENE SEDIMENTS OF A BURIED VALLEY IN NORTHFIELD CENTER TOWNSHIP, SUMMIT COUNTY, OHIO." University of Akron / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=akron1158259597.
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Ryter, Derek. "Late Pleistocene kinematics of the central San Jacinto fault zone, southern California /." view abstract or download file of text, 2002. http://wwwlib.umi.com/cr/uoregon/fullcit?p3072605.
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Thesis (Ph. D.)--University of Oregon, 2002.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 131-137). Also available for download via the World Wide Web; free to University of Oregon users.
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Meldahl, Keith Heyer. "Paleoenvironmental and stratigraphic implications of taphonomic processes: Case studies from Recent and Pleistocene shallow marine environments." Diss., The University of Arizona, 1990. http://hdl.handle.net/10150/185114.
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Taphonomic data can be applied to problems in paleoenvironmental analysis, stratigraphy and paleobiology. Ecologic and taphonomic data from molluscan assemblages in Recent clastic shallow marine environments (northern Gulf of California, Mexico, and Cape Cod, Massachusetts, U.S.A.) furnish different and complementary types of environmental information. Ecological data (species composition, trophic and life habit data) are regulated principally by substrate variation. In contrast, taphonomic data (abrasion, fragmentation, corrosion, bioerosion and encrustation) variously track shifts in surface residence time of shells, water energy, and tidal submergence time. Taphonomic contrasts between sedimentary environment arise because shells in different environments are altered along distinct "taphonomic pathways". Variation in residence time, water energy and tidal submergence time elicit responses in unique suites of taphonomic attributes. Taphonomic processes affect the distribution of fossils in strata, and this has important stratigraphic and paleobiologic ramifications. Shell concentrations in Pleistocene shallow marine strata in the northern Gulf of California formed either as beach ridge accumulations, tidal channel lags, autochthonous communities, or "unconformity beds". The latter are significant stratigraphic markers, capping angular unconformities. The "unconformity beds" are identified taphonomically as transgressive lags derived from beach face reworking during erosion of structural bulges that formed by periodic deformation along the Pleistocene shoreline. These shell beds are products of sedimentary processes along tectonically active continental margins. Preservational incompleteness of fossils hampers reconstruction of patterns of mass extinction, because biostratigraphic last occurrences nearly always underestimate times of lineage extinction. The distribution of biostratigraphic last occurrences of mollusc species in sediment cores from a Recent tidal flat indicates that sudden extinction can appear gradual, due to error in biostratigraphic range endpoints (Signor-Lipps effect). Extinction is typically not accurately recorded for species with less than 15% stratigraphic abundance (i.e. occurring in less than 15% of the sample intervals). Extinction simulations demonstrate that stratigraphic abundance and last occurrence data (readily available in the fossil record) can be used together to distinguish between sudden, stepwise and gradual patterns of mass extinction.
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McNabb, James. "Stratigraphic Record of Pliocene-Pleistocene Basin Evolution and Deformation Along the San Andreas Fault, Mecca Hills, California." Thesis, University of Oregon, 2014. http://hdl.handle.net/1794/17891.
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Sedimentary rocks in the Mecca Hills record a 3-4 Myr history of basin evolution and deformation within the southern San Andreas fault (SAF) zone. Detailed geologic mapping, measured sections, lithofacies analysis, and preliminary paleomagnetic data indicate that sedimentation and deformation in the Mecca Hills resulted from evolution of local fault zone complexities superimposed on regional subsidence and uplift. Sediment was derived from sources northeast of the SAF and transported southeast along the fault zone in large rivers, alluvial fans, and a smaller fault-bounded lake. Inversion of the Painted Canyon fault from oblique SW-side down to SW-side up slip was the main control on local deposition and deformation. Regional controls are suggested by an angular unconformity observed in the Mecca and Indio Hills along ~50 km of the SAF and synchronous post-740 ka uplift northeast of the SAF along ~80 km of the fault zone.
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Hazard, Colby. "Validity of Holocene Analogs for Ancient Carbonate Stratigraphic Successions: Insights from a Heterogeneous Pleistocene Carbonate Platform Deposit." BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5496.
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Observations of modern carbonate depositional environments and their accompanying depositional models have been used for decades in the reconstruction and interpretation of ancient carbonate depositional environments and stratigraphic successions. While these Holocene models are necessary for interpreting their more ancient counterparts, they inherently exclude important factors related to the erosion, diagenesis, and ultimate preservation of sediments and sedimentary structures that are ubiquitous in shallow marine carbonate environments. Andros Island, Bahamas is an ideal location to examine the validity of Holocene conceptual models, where geologically young (Late Pleistocene) limestones can be studied immediately adjacent to their well-documented modern equivalents. For this study, two 3D ground-penetrating radar (GPR) datasets (200 MHz and 400 MHz) were collected at a schoolyard in northwest Andros. These surveys reveal the geometries and internal characteristics of a peloidal-oolitic sand wave and tidal channel in unprecedented detail. These two prominent features are underlain by low-energy lagoonal wackestones and packstones, and are bordered laterally to the northwest by wackestones-packstones intermixed with thin sheets of peloidaloolitic grainstone. A deeper radar surface is observed at approximately 6 m depth dipping gently to the west, and is interpreted to be a karstified exposure surface delineating the base of a complete depositional sequence. Interpretation of the 3D radar volumes is enhanced and constrained by data from three cores drilled through the crest and toe of the sand wave, and through the tidal channel. This study is the first of its kind to capture the complex heterogeneity of a carbonate depositional package in three dimensions, where various depositional environments, sedimentary structures, and textures (mudstone to grainstone) have been preserved within a small volume.The results from this study suggest that the degree of vertical and lateral heterogeneity in preserved carbonate successions is often more complex than what can be observed in modern depositional environments, where sediments can generally only be observed in two dimensions, at an instant in time. Data from this study demonstrate the value of using two overlapping GPR datasets at differing resolutions to image the internal characteristics of a complete carbonate depositional package in three dimensions. From these datasets, a depositional model similar to other Holocene and Pleistocene carbonate depositional models is derived.
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Moore, Andrew Lathrop. "Combined use of lcast-size measurements and wave-tank experiments to estimate Pleistocene tsunami size at Molokai, Hawaii /." Thesis, Connect to this title online; UW restricted, 1999. http://hdl.handle.net/1773/6720.
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Wittmer, Jacalyn M. "Quantitative approaches and applications to the sequence stratigraphy and biodiversity of Pleistocene – Holocene mollusk communities from the Po plain, Italy and San Salvador Island, the Bahamas." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/56637.
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The following chapters presented here use modern ecological data and modern marine systems to evaluate past marine depositional settings and the preservation potential of various environments in the geological record.
While the chapters in this dissertation vary in terms of study area, sedimentary systems (carbonate vs. siliciclastic), depositional environment, and organisms, all projects are based on developing and using quantitative models to evaluate the present as a means for understanding the past.
Chapter one focuses on the preservation potential of rocky intertidal environments. The rocky intertidal zone is one of the most poorly preserved fossil-rich environments in the geological record. However in most coastal marine habitats today, it is one of the most diversity rich environments. Chapter one also focuses on the analytical advantages of hierarchical sampling of gastropod communities across San Salvador Island, the Bahamas to quantify community and species level preservation potential in rocky shore environments. Chapters two and three are based on the fossil-rich sedimentary deposits from the Po coastal plain in northeastern Italy. These deposits have been widely studied in terms of their sedimentology and stratigraphy, resulting in a highly resolved sequence stratigraphic architecture. The integration of sequence stratigraphy with paleobiology can enhance our understanding of spatiotemporal biotic patterns recorded in the fossil record. Used in conjunction with the highly-resolved stratigraphic framework, biotic patterns can be used to assess depositional cycles and bathymetry through time. Chapter two integrates sequence stratigraphic patterns and paleoecological data to develop bathymetric models across fossiliferous marine successions of the Po coastal plain, Italy. Chapter three evaluates the modern ecological dataset used to derive the bathymetric models. The last chapter also explores water depth distribution for selected taxa recorded in the Quaternary sediments and observed in present-day habitats. The dissertation research explored here demonstrates that modern ecological systems are essential to evaluating past geologic events. Through direct observation and quantitative analysis, I have learned that modern and fossil communities behave differently depending on environment (e.g. energy, salinity, water depth, etc.). These variables affect the distribution of living organisms today and through my research, delineate fossil distributions through time. With these observations, new questions have arisen about the latitudinal variability of rocky intertidal fossil preservation and extrapolating the quantitative bathymetric models to deeper time intervals. These questions will lead to future endeavors and pointedly add to the field of geology and stratigraphic paleobiology.Ph. D.
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Chapman, Timothy Ray. "Seismic tectono-stratigraphic study of the Pleistocene in the Sunrise/Troubadour area in relation to development of future infrastructure /." Title page, abstract and summary only, 1998. http://web4.library.adelaide.edu.au/theses/09SB/09sbc466pdf.
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Winsor, Jonathan Dion. "The Neogene development of the eastern Mediterranean Sea as manifested in and near the Rhodes Basin : an insight into arc-arc junctions /." Internet access available to MUN users only, 2004. http://collections.mun.ca/u?/theses,69327.
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Anderson, Noel P. "The use of soil characterization information in the correlation of Wisconsinan-age glacial drift in Randolph County, Indiana." Virtual Press, 1988. http://liblink.bsu.edu/uhtbin/catkey/544001.
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The upland soils of Randolph County, Indiana were studied for the following purposes: to provide an additional characterization of these soils, to identify a set of soil parameters that could delineate the extent of Late Wisconsinan glaciation in that county and to determine if there were any geographic trends in silt cap thickness. The study was prompted from observations by the recent Randolph County Soil Survey team that high clay content soils commonly associated with the county's Late Wisconsinan till (Lagro Formation) were found south of its previously mapped boundary.The only soil parameters that were effective in mapping the extent of Late Wisconsinan glaciation were: particle size analyses and some combinations of particle size analysis data with other soil parameters. The data support the previously mapped boundary of the Late Wisconsinan sediments in Randolph County, Indiana.Silt cap thickness was identified to be greatest in three areas of the county. However, the source(s) of these silts could not be determined.Department of Geology
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Mulder, Richard Alan. "Regional tectonic deformation of the northern Oregon coast as recorded by Pleistocene marine terraces." PDXScholar, 1992. https://pdxscholar.library.pdx.edu/open_access_etds/4433.
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Pleistocene marine terraces of the northern Oregon coast are an important factor in understanding the tectonics and paleoseismicity of the central Cascadia subduction zone. The lowest marine terrace, tentatively correlated to 80,000 year old Whiskey Run terrace of southern Oregon, is intermittently exposed in the present day sea cliff along an 80 km section of coastline between Tillamook Head and Cape Kiwanda. Terrace sediments consist largely of fine material such as clay, silt and fine sand with several locations containing large amounts of gravel derived from nearby headlands and steep bedrock hills. The terrace sediments are interpreted to be deposited in back-barrier marine environments, such as a bay, very similar to the bays which presently exist on the northern Oregon coast. Interbedded with terrace sediments are peat horizons which represent buried marsh or forest surfaces. These peat horizons have gradational lower contacts and abrupt upper contacts with terrace sediments indicating that the marsh or forest surfaces formed gradually above sea level and were suddenly downdropped below sea level to be buried by bay sediments. Such features are consistent with a seismically active Cascadia subduction zone which produces interseismic coastal uplift and coseismic coastal subsidence.
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Nicholl, Joseph Anthony Leo. "Changes in ice sheet dynamics across the mid-Pleistocene transition recorded in North Atlantic sediments." Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648858.
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Selby, Katherine. "Late Devensian and Holocene relative sea level changes on the Isle of Skye, Scotland." Thesis, Coventry University, 1997. http://curve.coventry.ac.uk/open/items/0e151cae-7151-0ae4-e4f3-99a45f12ce84/1.
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Five coastal sites have been studies on the Isle of Skye to investigate Late Devensian and Holocene relative sea level changes. In the field, detailed stratigraphical work, geomorphological mapping and levelling were undertaken and representatives cores were sampled. Detailed pollen and diatom analyses were undertaken in the laboratory and samples were submitted for radiocarbon assay where distinct pollen, diatom or lithostratigraphical changes were recorded. Loss on ignition analysis was also undertaken to ascertain the carbon content of the samples. The investigations have revealed that during the Late Devensian marine transgressions were experienced at two sites in southern Skye. These are thought to relate to readvances of the ice that arrested the isostatic recovery of the land, caused renewed isostatic depression and upon deglaciation, allowed marine waters to penetrate the sites. At Inver Aulavaig the transgression is thought to relate to the Wester Ross Readvance recorded in Wester Ross, Coll and Tiree and at Point of Sleat the transgression is thought to relate the Loch Lomond Readvance recorded extensively in Scotland. Relative sea level at Point of Sleat (southern Skye) then fell below an altitude of 4.13mOD at 10460+-50BP and remained low during the early Holocene until the Main Postglacial Transgression occurred. This transgression is recorded at three of the sites: at Inver Aulavaig (southern Skye) at 8850+-70BP where it had attained an altitude of at least 5.10mOD, at Peinchorran (eastern Skye) where it is thought to have been underway by 7980+-BP and attained an altitude of 4.49mOD and at Talisker Bay (western Skye) at 7790+-100BP where it had attained an altitude of -2.18mOD. At Ardmore Bay (northern Skye) it is thought that the Main Postglacial Transgression did not reach an altitude of 3.34mOD. It is possible that barrier formation at some of the sites accompanied the early states of the Mian Postglacial Transgression. It is thought that regression of the sea occurred between circa 6600 BP and circa 5400 BP and remained low until circa 4200 BP when a later rise in relative sea level took place at Peinchorran attaining a maximum altitude of 4.90mOD. A late Holocene transgression is also recorded at Point of Sleat at between circa 3800 BP and circa 2900 BP where it attained an altitude of greater than 4.13mOD and at Inver Aulavaig after circa 3200 BP where it attained an altitude of between 5.10-6.01mOD. It is unclear whether this episode of high relative sea level represents the diachronous nature of one late Holocene transgression or several fluctuations in relative sea level during the late Holocene. Following the late Holocene transgression, relative sea level fell until the present day. Comparison of the data obtained from Skye with the isobase maps and rheological models suggests that the isobases for the Main Lateglacial Shoreline (Firth et al., 1993) show a good fit in age and altitude but the rheological model of Lambeck (1993b) for 10500 BP requires modification. The isobases for the Main Postglacial Shoreline appear to lie circa 4m too high for the sites studied on Skye and the isobases produced for a late Holocene shoreline appear to be greatly in error (Firth et al., 1993). It is possible that the build up of ice during the Loch Lomond Stadial may have had a greater effect on crustal movements than previously thought and this may account for discrepancies identified in the isobase maps. The study of isolation basins and back-barrier environments has allowed an assessment of their potential in recording relative sea level changes. The use of isolation basins in areas devoid of estuarine sedimentation has been particualrly demonstrated. The vegetation reconstruction undertaken, suggests that variations do occur in coastal locations compared to sites further inland, although these are subtle. The dates obtained for the increase in taxa such as 'Corylus avellana' and 'Alnus' and the recording of anthropogenic indicators on the vegetation, agree with those previously obtained for Skye. The use of pollen analysis in verifying the radiocarbon dates obtained, particualrly for the Late Devensian, has been recognised and, combined with diatom analysis, has provided a comprehensive database from which to reconstruct past relative sea levels.
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Paquet, Fabien. "Morphostructural evolution of active margin basins : the example of the Hawke Bay forearc basin, New Zealand : a thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy in Geology at the University of Canterbury /." Thesis, University of Canterbury. Geological Sciences, 2007. http://hdl.handle.net/10092/1474.
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Topography growth and sediment fluxes in active subduction margin settings are poorly understood. Geological record is often scarce or hardly accessible as a result of intensive deformation. The Hawke Bay forearc basin of the Hikurangi margin in New Zealand is well suited for studying morphstructural evolution. It is well preserved, partly emerged and affected by active tectonic deformation during Pleistocene stage for which we have well dated series and well-known climate and eustasy. The multidisciplinary approach, integrating offshore and onshore seismic interpretations, well and core data, geological mapping and sedimentological sections, results in the establishment of a detailed stratigraphic scheme for the last 1.1 Ma forearc basin fill. The stratigraphy shows a complex stack of 11 eustasy-driven depositional sequences of 20, 40 and 100 ka periodicity. These sequences are preserved in sub-basins that are bounded by active thrust structures. Each sequence is characterized by important changes of the paleoenvironment that evolves between the two extremes of the glacial maximum and the interglacial optimum. Thus, the Hawke Bay forearc domain shows segmentation in sub-basins separated by tectonic ridges during sea level lows that become submerged during sea level highs. Over 100 ka timescale, deformation along active structures together with isostasy are responsible of a progressive migration of sequence depocenters towards the arc within the sub-basins. Calculation of sediment volumes preserved for each of the 11 sequences allows the estimation of the sediment fluxes that transit throughout the forearc domain during the last 1.1 Ma. Fluxes vary from c. 3 to c. 6 Mt.a⁻¹. These long-term variations with 100 ka to 1 Ma timescale ranges are attributed to changes in the forearc domain tectonic configuration (strain rates and active structure distribution). They reflect the ability of sub-basin to retain sediments. Short-term variations of fluxes (<100 ka) observed within the last 150 ka are correlated to drastic Pleistocene climate changes that modified erosion rates in the drainage area. This implies a high sensitiveness and reactivity of the upstream area to environmental changes in terms of erosion and sediment transport. Such behaviour of the drainage basin is also illustrated by the important increase of sediment fluxes since the European settlement during the 18th century and the following deforestation.
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Shackford, Julia Keegan. "Continuous Late Pleistocene Paleoclimate Record from the Southwest African Margin: A Multi-Proxy Approach." unrestricted, 2005. http://etd.gsu.edu/theses/available/etd-04212005-174202/.
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Thesis (M.S.)--Georgia State University, 2005.Title from title screen. Beth A. Christensen, committee chair; W. Crawford Elliott, Eirik J. Krogstad, Deborah Freile, committee members. Description based on contents viewed Dec. 22, 2006. Includes bibliographical references (p. 107-112).
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Karls, Deborah G. "Petrographic and geochemical analysis of detrital magnetite in late Wisconsinan tills in eastern Indiana and western Ohio." Virtual Press, 2005. http://liblink.bsu.edu/uhtbin/catkey/1314330.
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Detrital magnetite, although averaging less than I% of till volume, is a common constituent in glacial tills of eastern Indiana and western Ohio. Because of its abundance and ease of sampling, detrital magnetite was chosen to determine its potential as a tool to 1) determine provenance of the glacial tills and 2) to chemically fingerprint glacial sedimentary deposits for use in stratigraphic analysis. Two sampling programs were performed. First, glacial till samples were collected from a vertical section in western Ohio at the location of Doty's High Bank. Second, glacial tills were collected from a lateral distribution of five moraines in northeast and east central Indiana.Petrographic analysis of 946 detrital magnetite grains from eastern Indiana and western Ohio has shown that 81% of the magnetite grains are homogeneous, 15% have magnetite-ilmenite intergrowths, and 4% have exsolved phases of ulvospinel/pleonaste.Eighteen percent of all detrital magnetite grains have some level of hematite alteration. Chemical analyses were performed on 403 homogeneous detrital magnetite grains. These grains were analyzed for Fe, Ti, Mg, Mn, Cr, V, Al, and Si. The means and standard deviations of these eight elements, in weight percent oxide, are FeO (89.8087.696), TiO2 (1.58 ± 4.99), MgO ( 0.052 ± 0.200), MnO ( 0.172 ± 0.284), Cr2O3 (0.1942.256), V2O3 ( 0.241 ± 0.245), Al2O3 (0.455 ± 1.234), and SiO2 ( 0.035 ± 0.047).A Canadian source north of Lake Huron and south of James Bay is suggested based on previous studies of flow directions of the Laurentide Ice Sheet and bedrock geology in southern Canada. The bedrock in this area is primarily felsic plutonic and mafic volcanic. The petrographic and geochemical results of this study indicate this area as the source area for the detrital magnetite in eastern Indiana and western Ohio tills. Chemical fingerprints based on cluster analysis and bivariate plots were found within the vertical exposure of Doty's High Bank and the lateral moraines of eastern Indiana. Samples from the Muncie esker (unknown age) were found to correlate with the southernmost set of eastern Indiana moraines based on the chemical fingerprint analysis.Department of Geology
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Dewey, Felicity Joy. "The sedimentology and palaeoenvironmental significance of vlei sediments on the Winterberg range, South Africa." Thesis, Rhodes University, 1989. http://hdl.handle.net/10962/d1001897.
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Palaeoenvironmental reconstruction of the late Pleistocene and Holocene geological periods for central and southern Africa has been hampered by the erratic distribution of suitable sites, incomplete and inaccurately dated sequences and the limited nature of published data. One geomorphological feature which has supplied valuable evidence for fluctuations in past environmental conditions, is the vlei or dambo. The type-site of these waterlogged features is in south central Africa, but similar features have been described on other continents. The clastic and organic sediments contained within these features are affected by, and therefore reflect to some degree, the environment under which they were formed. The characteristics of the sediments supply information as to their transport and mechanisms of deposition. From these processes, the environmental conditions at the time of vlei formation can be inferred. The environmental history of the Eastern Cape region has been considerably neglected, and is far less well understood than other countries such as Malawi, Zambia and Zimbabwe. A study site in the Winterberg Range (Eastern Cape) was selected which permitted the comparison of two vleis, the objective being to establish an accurate late Pleistocene sediment chronology for the entire plateau area. Radiocarbon dates from organic layers indicate that these sediments span the last 12 000 years BP, suggesting that organic accumulation at this site began at roughly the same time as at sites further afield. The vlei sediments are analysed in terms of their morphology, particle slze distribution, and other physical and chemical characteristics. These data facilitate the construction of detailed stratigraphic diagrams and a chronological summary of sediment accumulation, from which the period and governing processes of vlei development under changing environments may be described. It is found that the Winterberg vleis contain sediments which respond to changes in the prevailing environment. This makes these sediments useful indices from which to trace such changes during the late Pleistocene and Holocene times. These features are found to be similar in many respects to those described elsewhere in Southern Africa. The study attempts to provide greater understanding of contemporary vlei processes and emphasises the necessity of their preservation, as finite and valuable resources, by future generations
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Leroux, Estelle. "Quantification des flux sédimentaires et de la subsidence du bassin Provençal." Phd thesis, Université de Bretagne occidentale - Brest, 2012. http://tel.archives-ouvertes.fr/tel-00790852.
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Le Golfe du Lion et le Bassin Provençal sont l'objet de recherche intensive à toute échelle de temps et d'espace. Cependant, les budgets sédimentaires et les mouvements verticaux depuis la formation de la marge étaient restés inconnus ou sources de controverses. Ce travail se propose d'aborder leur quantification à partir de l'interprétation de nombreux profils sismiques, d'après les concepts de stratigraphie sismique et séquentielle [Vail et al., 1977], complétée par des données de forages et de sismique réfraction, et validée par des modélisations stratigraphiques avec Dionisos [Granjeon and Joseph, 1999]. L'établissement d'une continuité stratigraphique entre le domaine de plate-forme et le bassin profond offre une vision complète du remplissage sédimentaire de la marge. Les repères stratigraphiques du Plio-Pléistocène (2.6 Ma, 1.6 Ma, 0.9 Ma et 0.45 Ma) ont en effet été corrélés jusqu'au pied de pente. Les jalons messiniens, établis lors des travaux précédents [Bache, 2008] ont également été étendus et précisés localement. La mise en évidence d'une nouvelle unité, interprétée comme les résidus de l'abrasion lors de la transgression mettant fin à la célèbre crise, permet d'apporter des arguments pour l'établissement d'un nouveau scénario de l'évènement [Bache et al., 2012a](soumis). Des lois de conversion en profondeurs (métriques) des différentes unités chronostratigraphiques ont ensuite été établies en 3D à partir de l'ensemble des données de forage et de réfraction (ESP) et appliquées pour chacune de nos unités. Les profondeurs de l'ensemble des jalons plio-pléistocènes et messiniens ont ainsi pu être cartographiées, ainsi que les épaisseurs de chacune des unités définies depuis le substratum jusqu'à l'actuel (1 au Miocène, 6 au Messinien, 5 au Plio-Pléistocène). Les épaisseurs et volumes sédimentaires déposés ont alors pu être quantifiés sur chaque intervalle stratigraphique. Les séries sédimentaires ont été par la suite décompactées et les volumes "vrais" de dépôts et flux sédimentaires recalculés. Il en résulte une augmentation très forte (X2) des apports détritiques autour de 1 Ma en liaison avec les changements climatiques de la révolution Mi-Pléistocène, et le changement de fréquence et d'amplitude des cycles eustatiques. L'accélération mondiale (par 3) des flux terrigènes il y a 5 Ma, défendue par de nombreux auteurs et corrélée avec un soulèvement des grandes orogènes (ici en liaison avec les Alpes), est également observée dans notre bassin, même si la célèbre crise de salinité messinienne tend à perturber le signal. On suggère qu'elle soit en partie responsable de ce pic détritique à 5 Ma. La chute du niveau marin (estimée à 1500 m par [Clauzon, 1982]) et l'érosion qui lui est associée entraînent en effet un transfert considérable de sédiments d'amont en aval. Les flux détritiques sont ainsi multipliés par 15 pendant le Messinien par rapport au Miocène. Nos modélisations stratigraphiques de la crise messinienne ont par ailleurs permis de démontrer la validité de l'hypothèse de [Bache, 2008], [Bache et al., 2012b] quant à l'ampleur des dépôts détritiques issus de l'érosion et du démantellement de la marge. La géométrie des dépôts nous a également fourni de précieux indicateurs des mouvements verticaux ayant affectés les sédiments depuis le rifting. Trois domaines différents de subsidence sont distingués : les domaines de plate-forme, de pente (où la subsidence prend la forme d'un basculement) et le bassin profond (qui s'affaisse de façon purement verticale). Trois lignes charnières ou hinge-line sont ainsi définies : - la première située entre 15 à 20 km en amont du trait de côte actuelle, au début de l'amincissement de la croûte (première remontée du Moho) - la deuxième au niveau de la rupture de pente de l'actuel plateau au-dessus à la transition avec un domaine de croûte continentale plus fortement amincie au sein duquel un sous domaine anomalique à fortes vitesses sismiques est observé, - la troisième à l'aplomb de la transition entre le domaine à croûte continentale fortement amincie et le domaine à croûte atypique. Sur la plate-forme, le basculement plio-pléistocène quantifié par [Rabineau, 2001], [Rabineau et al., soumis), est démontré constant dans le temps et globalement dans l'espace et estimé à 0,16°/Ma et validée par des simulations en 2D. La subsidence post-rift moyenne (depuis 20 Ma) du plateau, quant à elle, apparaît inférieure et variable dans le temps et l'espace. Elle est estimée à 0,11°/Ma sur la plate-forme occidentale, à 0,06°/Ma sur la plate-forme orientale, impliquant une subsidence miocène quasi-nulle sur la plate-forme rhodanienne. La subsidence post-rift moyenne est cependant mesurée sur des réflecteurs qui ont probablement subi des réajustements isostatiques liés à l'événement messinien. Quantifier l'ampleur de ces réajustements isostatiques s'avère donc essentiel pour mieux contraindre la subsidence. L'ordre de grandeur de ces réajustements a été mesuré à 1300 m sur la plate-forme externe occidentale au niveau des canyons de la zone Aude-Hérault, se rapprochant de l'estimation de [Mauffret et al., 2001]. Dans le bassin profond, la subsidence post-rift verticale (depuis 20 Ma) est, elle, estimée à 500 m/Ma. Une simulation préliminaire avec Dionisos, incluant les lignes charnières définies, et considérant un taux de basculement constant de 0,16°/Ma sur le plateau, une subsidence verticale de 500 m/Ma dans le bassin, et un basculement constant sur la pente accommodant les subsidences de part et d'autre, reproduit l'architecture sédimentaire de la marge à partir d'une topographie initiale plane. Elle montre donc que l'hypothèse d'une subsidence post-rift constante du bassin de 500 m/Ma depuis 20 Ma (similaire à celle indiquée par [Séranne, 1999]) est possible, même si un taux de subsidence miocène plus faible n'est pas à exclure. L'enregistrement sédimentaire permet donc de décrypter les lois de subsidence qui semblent corrélées aux diffé- rents grands domaines structuraux sous-jacents : (1) le domaine à croûte continentale, (2) celui à croûte continentale amincie et (3) le domaine à croûte intermédiaire. La position haute de la plate-forme pendant le rifting [Bache, 2008], [Bache et al., 2010], les taux de subsidence particulièrement forts calculés dans cette étude, ainsi que le mouvement subsidant purement vertical dans le bassin ne correspondent pas à l'évolution attendue d'après les modèles conservatifs d'extension des marges. De précédentes études menées sur les marges atlantiques [Moulin et al., 2005], [Aslanian et al., 2009], [Labails et al., 2010] avaient déjà mis l'accent sur ce point. Les résultats de nos travaux confirment donc la nécessité de considérer de nouveaux modèles d'évolution des marges dites passives [Aslanian et al., 2009], [Bache et al., 2010].
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Cepeda, Raquel. "Three-dimensional seismic stratigraphic interpretation of the upper miocene to lower pleistocene deep-water sediments of the Thunder Horse-Mensa area, southern Mississippi Canyon, northern deep Gulf of Mexico." Diss., Connect to online resource, 2005. http://wwwlib.umi.com/cr/colorado/fullcit?p1427771.
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Richards, Andrew Edward. "The Pleistocene stratigraphy of Herefordshire." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323676.
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Whiteman, Colin Allerton. "Middle Pleistocene stratigraphy in mid-Essex, England." Thesis, Birkbeck (University of London), 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.577466.
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Kadastik, Ene. "Upper-pleistocene stratigraphy and deglaciation history in northwestern Estonia /." Online version, 2004. http://dspace.utlib.ee/dspace/bitstream/10062/806/5/kadastik.pdf.
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Hibbert, Fiona Danielle. "Dynamics of the British Ice Sheet and prevailing hydrographic conditions for the last 175,000 years : an investigation of marine sediment core MD04-2822 from the Rockall Trough." Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/3136.
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This study presents a stratigraphic investigation of the marine sediment core MD04-2822 from the Rockall Trough (56° 50.54' N, 11° 22.96' W; 2344 m water depth). This core is currently the only available high resolution record for the calibration of Late Quaternary sedimentary sequences of the British (Hebridean) margin. It therefore offers an unprecedented archive of changing sedimentological and climatological conditions for the last 175,000 years. The high resolution, multi-proxy records have enabled surface and deep water conditions within the Rockall Trough to be reconstructed. In addition, the fluctuating nature of ice-rafted debris (IRD) inputs to the MD04-2822 site allows a first order attempt of BIS dynamics for the entirety of the last glacial period (i.e. from the demise of the last interglacial to the decay of the Devensian/Weichselian ice sheet) as well as the majority of the penultimate (Saalian/MIS 6) glaciation. Sediment core MD04-2822 is ideally located to capture the dynamics of the British Ice Sheet (BIS) via a continuous record of IRD and fine-grained terrigenous inputs. Fundamental to this is the construction of a robust chronology. This was achieved via: the correlation of the benthic δ¹⁸O record to a global δ¹⁸O stack (SPECMAP); the correlation of the surface proxies (% N. pachyderma (sinistral) and XRF Ca) to the Greenland δ¹⁸O and Antarctic methane ice core records; and radiocarbon dating. This chronology was validated using both radiocarbon dating and tephra horizons. An evaluation of the event stratigraphy approach used in the construction of the MD04-2822 chronology is presented. The marine record provides a valuable archive of past ice sheet dynamics as much terrestrial evidence is removed or obscured by subsequent ice sheet oscillations MD04-2822 provides the first evidence for the expansion of the BIS onto the Hebridean Margin during MIS6 (thereby confirming previous long-range seismic correlations). The continuous sedimentation at MD04-2822 enabled the first insights into the early dynamics of the last BIS. Increases in IRD and fine grained terrigenous material delivered to the MD04-2822 at ca. 72 kyr represent the first significant delivery of material from the BIS across the continental shelf to the core site. The BIS would therefore have attained a marine calving margin by this time. A multi-proxy investigation of provenance was undertaken, however unequivocal provenance determinations remain problematic. The location of the core suggest the proximal BIS as the most likely source of terrigenous inputs. The expanded nature of the MD04-2822 sediments during the penultimate deglacial (Termination II) provides the first details of BIS dynamics for this period: the interplay of large inputs of freshwater from the decay of the Saalian (MIS 6) ice sheets (including the BIS) upon the surface and deep water circulation of the North Atlantic is investigated. In addition, sub-orbital climatic variability is documented at this location throughout the last interglacial (MIS 5e) and appears to be an intrinsic feature of both the N.E. Atlantic surface and deep water circulation of the last 175 kyr.
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Hallam, David Frank. "Palaeomagnetic investigations of Early and Middle Pleistocene sediments in East Anglia, UK." Thesis, University of East Anglia, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282974.
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Wazi, Nandefo. "Le crétacé du Roumois (Vallée de l'Oison) et le tertiaire-quaternaire des régions voisines de la basse vallée de la Seine : stratigraphie et tectonique." Rouen, 1988. http://www.theses.fr/1988ROUES030.
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Etude de la série crétacé du Roumois à partir de l'analyse lithostratigraphique de nombreuses coupes. La définition précise des formations sédimentaires de l'Aptien-Albien au Coniacien-Santonien est étagée par une étude biostratigraphique et séquentielle qui permet d'individualiser dix formations. Inventaire des témoins éocènes à pléistocènes de la région de la Basse Seine. Détermination du style tectonique du plateau du Roumois à partir d'une cartographie détaillée et d'une analyse structurale d'anciens documents géologiques et géophysiques. On propose une interprétation reghmatique en décrochements potentiels. Chronologie des évènements tectono-sédimentaires ayant affecté la région
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Kemna, Hans A. Hemna Hans Axel. "Pliocene and Lower Pleistocene Stratigraphy in the Lower Rhine Embayment, Germany /." Köln : Institut für Geologie und Mineralogie der Universität zu Köln, 2005. http://opac.nebis.ch/cgi-bin/showAbstract.pl?u20=3934027172.
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Scourse, J. D. "Late Pleistocene stratigraphy of the Isles of Scilly and adjoining regions." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355026.
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Ansari, Murtaza H. "Stratigraphy and palaeobotany of Middle Pleistocene interglacial deposits in the North Sea." Thesis, Bangor University, 1992. https://research.bangor.ac.uk/portal/en/theses/stratigraphy-and-palaeobotany-of-middle-pleistocene-interglacial-deposits-in-the-north-sea(b1b73ba6-2451-4c06-b1c9-81b68e57b39a).html.
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This study presents a detailed palynological investigation of Middle Pleistocene interglacial sediments from the North Sea. A borehole and three vibrocores from the Inner Silver Pit area of the southern North Sea, and a borehole from the Devil's Hole area of the central North Sea, have been investigated. The palynological investigation has been supplemented by micropalaeontological and sedimentological analyses and also by seismic data. The sequence recovered in borehole 81/52A from the Inner Silver Pit presents a depositional record from the mid-Anglian to the Wolstonian glacial stage. Glacigenic sediments overlying Cretaceous Chalk correlate with the Lowestoft Till (Anglian). The depositional history of the interglacial cycle indicates that during the pre-temperate substage extensive erosional activity occurred in coastal areas causing a large proportion of reworked pollen and a very low amount of contemporaneous pollen to be deposited. The sequence preserves a good vegetational record of the early-temperate (HoII), late-temperate (HoIII) and post-temperate (HoIV) substages. The pollen assemblages representing HoIlI and HolV are very similar to the pollen assemblages of these substages from Marks Tey, Essex. The pollen assemblage representing HoII is different from Marks Tey in having a high proportion of Picea; as such it shows similarity with the pollen assemblages found at Nechells, Birmingham. The sequence of the sands and gravels can be correlated with the Wolstonian sands and gravels at Tottenhill in the Nar Valley, North Norfolk and with Saalian sediments in the Dutch sector of the North Sea. Three vibrocores, 53/00/962, /1103 and /1104, from the Inner Silver Pit area provide additional data and represent various parts of the Hoxnian interglacial stage. Pollen data from borehole 81/34 from the Devil's Hole area suggests that the sequence representing the Ling Bank Formation does not represent a single interglacial stage but rather two interglacial stages (separated by a cold stage) within the Cromerian Complex.
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Warren, Jeffrey Dennis Bartek Louis Robert. "The sequence stratigraphy of the East China Sea continental margin (late Pleistocene to present)." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,171.
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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2006.Title from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Geological Sciences." Discipline: Geology; Department/School: Geological Sciences.
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Peryam, Thomas, and Thomas Peryam. "Sedimentation, Climate Change and Tectonics: Dynamic Stratigraphy of the Pliocene-Pleistocene Fish Creek-Vallecito Basin, California." Thesis, University of Oregon, 2012. http://hdl.handle.net/1794/12519.
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In order to better understand the interactions between climate change, landscape erosion and sedimentation, a detailed study was conducted on Plio-Pleistocene non-marine deposits of the Palm Spring Group in the Fish Creek-Vallecito basin, California, USA. Three inter-related studies focused on (1) local response to global climate change in late Pliocene-early Pleistocene time, (2) large-scale evolution of lithofacies architecture, and (3) climate modulation of late Pliocene sediment flux on Milankovitch time scales.
Stable isotopes and paleosol classification reveal that between ~4.0 and 0.75 Ma, aridity increased in the study area concurrent with a shift towards a less intense and more winter-dominated precipitation regime. These changes are interpreted to reflect the long-term waning of summer monsoon precipitation in southern California.
A dramatic and enigmatic reorganization of basin strata occurred at 2.9 Ma. Detailed basin analysis shows that locally-derived sediment was supplied by the predecessors of two modern drainages, Vallecito and Carrizo creeks. Initial progradation of alluvial deposits from these two sources across the Colorado River delta plain began between 4.0-3.4 Ma. At 2.9 Ma, rapid progradation of these two deposystems was coeval with emplacement of a megabreccia and transgression of Borrego Lake. My data indicate that tectonic realignments at both local and regional scales drove this reorganization.
Time series analysis of rock magnetic data from a densely-sampled stratigraphic section of the lacustrine Tapiado Formation reveals that between 2.9 and ~2.75 Ma landscape denudation in the Carrizo Creek catchment was partly modulated by orbital obliquity. Peaks in landscape denudation implied by my data correspond to obliquity highs. More frequent high intensity precipitation events (i.e. monsoons and tropical storms) probably drove increased erosion during these time periods relative to obliquity lows. The breakdown of this relationship at around 2.75 Ma corresponds to a dramatic increase in northern hemisphere glaciation and may reveal a reduction in monsoonal influence in southern California.
A geologic map of the Fish Creek-Vallecito basin is included as a supplemental file to this dissertation.
This dissertation contains previously published and unpublished coauthored material.
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Langford, Harry. "Sedimentological, palaeogeographical and stratigraphical aspects of the Middle pleistocene geology of the Peterborough area, eastern England." Thesis, Anglia Ruskin University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326053.
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Praeg, Daniel. "Morphology, stratigraphy and genesis of buried mid-Pleistocene tunnel-valleys in the southern North Sea Basin." Thesis, University of Edinburgh, 1996. http://hdl.handle.net/1842/15659.
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Kim, Booyong. "Seismic sequence stratigraphy of Pliocene-Pleistocene turbidite systems, Ship Shoal South Addition, Northwestern Gulf of Mexico." Texas A&M University, 2002. http://hdl.handle.net/1969/522.
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Knorr, Paul Octavius. "The case for high-order, pleistocene sea-level fluctuations in Southwest Florida." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001791.
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Maike, Christopher A. "A Flood-Tidal Delta Complex, The Holocene/Pleistocene Boundary, and Seismic Stratigraphy in the Quaternary Section off the Southern Assateague Island Coast, Virginia, USA." University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1408097363.
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Rahmanov, Ogtay Rasim. "Sequence stratigraphy of the late Pleistocene - Holocene deposits on the northwestern margin of the South Caspian Basin." Texas A&M University, 2003. http://hdl.handle.net/1969.1/1185.
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Interpretation of 900 km of a closely spaced grid of high-resolution seismic profiles over the northwestern margin of South Caspian Basin (SCB) allows recognition and study of six late Pleistocene - Holocene depositional sequences.
Sequence stratigraphy analysis of sedimentary strata from 117,000 years B.P. to present led to the identification of a highstand systems tract, two transgressive systems tracts and six lowstand systems tracts. Each systems tract is characterized by specific seismic facies. Diverse depositional processes on the northwestern margin of the SCB are suggested by the thirteen seismic facies patterns recognized in the study area. Two distinct progradational complexes were interpreted within Sequence III and Sequences IV and V in the northeastern and northwestern parts of the study area, respectively. Stratigraphic interpretation of the sequences provided important information on parameters that control depositional architectures, such as lake level fluctuations, tectonic dynamics, and sediment supply.
High sedimentation rates combined with a series of high-frequency and high-amplitude lake-level fluctuations, abrupt changes at the shelf edge, abnormally high formation pressure, and high tectonic activity during Quaternary time resulted in the development of a variety of complex geologic drilling hazards. I distinguished three types of hazards as a result of this study: mud volcanoes, sediment instability, and shallow gas.
The 2D high-resolution seismic dataset from the northwestern margin of the SCB allowed more detailed seismic sequence stratigraphic analysis in the study area than has previously been attempted. In particular, it has a clear application in deciphering sediment supply and relative lake level changes as well as tectonic relationship of the northwestern shelf margin of the SCB.
Results of this work led us towards better understanding of recent depositional history, improved our knowledge of the nature of the basin tectonics, climate history and styles of and controls on sedimentation processes within a sequence stratigraphic framework during the late Pleistocene-Holocene time.
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Quinn, Irene M. "The stratigraphy and morphology of Pleistocene deposits in County Waterford (with special reference to the Ballyvoyle Till)." Thesis, London Metropolitan University, 1987. http://repository.londonmet.ac.uk/3069/.
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The Ballyvoyle Till (Watts, 1959) was originally described by Wright and Muff (1904) as a boulder clay deposited by southerly-moving ice of Inland, northern origin. They regarded this advance as having post~dated one of Irish Sea origin along the south coast. While Watts (1959) considered that the two ice masses were broadly contemporaneous, Synge (1977) suggested that the glacigenic sequence predated the deposition of the underlying raised beach and was subsequently soliflucted downslope to Its present stratigraphic position overlying the raised beach unit.
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Mlađen, Jovanović. "Средње плеистоцене лесно-палеоземљишне секвенце Војводине." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 2012. https://www.cris.uns.ac.rs/record.jsf?recordId=83269&source=NDLTD&language=en.
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Детаљним теренским и лабораторијским истраживањима четири најважнија лесно-палеоземљишна профила у нашој земљи: Батајница – Дунав, Стари Сланкамен – Чот, Рума – циглана и три профила на Тителском лесном платоу, обухваћено је преко 160 mпрофила, а прикупљено је и лабораторијски обрађено преко 3.500 узорака, што до сада представља најобимније и најдетаљније истраживање лесно-палеоземљишних секвенци (ЛПС) у нашој земљи. Дат је детаљан литолошки и педолошки опис ЛПС, које су формиране у различитим палеогеографским условима. На основу резултата палеомагнетских истраживања која су обављена у две независне лабораторије и на два сета спесимена, прецизно је дефинисан положај последње пуне геомагнетне реверзије (бринес/матујама) која се одиграла пре 778 хиљада година. У исто време она представља званични границу између доњег и средњег плеистоцена. На основу позиције ове границе у доњем делу лесног хоризонта V-L9, формирана је нова интерпретација постојећег хроностратиграфског модела. Истраживањима особина стенског магнетизма, коришћењем параметара магнетне сусцептибилности и магнетне сусцептибилности зависне од фреквенце, формирана је јасна слика о палеоклиматским условима који су постојали током формирања слојева леса и образовања серије фосилних земљишта. Транзиција од екосистема суптропског појаса завршног дела доњег плеистоцена и почетног дела средњег плеистоцена, преко шума умереног појаса током средњег дела средњег плеистоцена, ка степским палеоземљиштима у каснијим периодима плеистоцена, јасно је осликана у типовима фосилних земљишта.Detaljnim terenskim i laboratorijskim istraživanjima četiri najvažnija lesno-paleozemljišna profila u našoj zemlji: Batajnica – Dunav, Stari Slankamen – Čot, Ruma – ciglana i tri profila na Titelskom lesnom platou, obuhvaćeno je preko 160 mprofila, a prikupljeno je i laboratorijski obrađeno preko 3.500 uzoraka, što do sada predstavlja najobimnije i najdetaljnije istraživanje lesno-paleozemljišnih sekvenci (LPS) u našoj zemlji. Dat je detaljan litološki i pedološki opis LPS, koje su formirane u različitim paleogeografskim uslovima. Na osnovu rezultata paleomagnetskih istraživanja koja su obavljena u dve nezavisne laboratorije i na dva seta spesimena, precizno je definisan položaj poslednje pune geomagnetne reverzije (brines/matujama) koja se odigrala pre 778 hiljada godina. U isto vreme ona predstavlja zvanični granicu između donjeg i srednjeg pleistocena. Na osnovu pozicije ove granice u donjem delu lesnog horizonta V-L9, formirana je nova interpretacija postojećeg hronostratigrafskog modela. Istraživanjima osobina stenskog magnetizma, korišćenjem parametara magnetne susceptibilnosti i magnetne susceptibilnosti zavisne od frekvence, formirana je jasna slika o paleoklimatskim uslovima koji su postojali tokom formiranja slojeva lesa i obrazovanja serije fosilnih zemljišta. Tranzicija od ekosistema suptropskog pojasa završnog dela donjeg pleistocena i početnog dela srednjeg pleistocena, preko šuma umerenog pojasa tokom srednjeg dela srednjeg pleistocena, ka stepskim paleozemljištima u kasnijim periodima pleistocena, jasno je oslikana u tipovima fosilnih zemljišta.
Detailed field and laboratory studies of four major loess-paleosol sequences in our country: Batajnica - Danube, Stari Slankamen - Čot, Ruma - brickyard and three sub-profiles on the Titel loess plateau, is covered by over 160 m of sections and collected and laboratory analyzed over 3,500 samples, which so far is the most comprehensive and most detailed research of loess-paleosol sequences (LPS) in our country. A detail description of the lithological and pedological LPS, which are formed in different paleogeographical conditions, was presented. Based on the results of palaeomagnetic experiments which ware performed in two independent laboratories and on the two sets of specimen, the position of Matuyama/Brunhes boundary whics took place 778 ka, was precisely defined. At the same time it is the official boundary between the Lower and Middle Pleistocene. Based on the position of this magnetic reversal in the lower part of loess horizons V-L9, a new interpretation of existing chronostratigraphic models was formed. Investigation of the rock magnetism properties, using the magnetic susceptibility and frequency dependent magnetic susceptibility, a clear picture of the palaeoclimate conditions that existed during the formation of layers of LPS was formed. The transition from the subtropical zone ecosystems of the final part of the Lower Pleistocene and the initial portion of the Middle Pleistocene, through forests of temperate belt during the middle part of the Middle Pleistocene, to the steppe paleosol in the later periods of the Pleistocene, is reconstructed according different soil types.
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Davies, Quintin James. "Climatic and tectonic controls on deep water sedimentary cyclicity : evidence from the Miocene to Pleistocene of Cyprus." Thesis, Open University, 2001. http://oro.open.ac.uk/54616/.
Full textAbstract:
Traditionally, sedimentation at active plate margins is thought to be dominantly controlled by tectonism, with any climatic cyclicity being overprinted. Since the early Miocene, Cyprus has been situated above an active subduction zone, which has strongly influenced the regional tectonics. Global climate change also occurred during the Miocene marking a transition from relative global warmth of the early-Miocene to the Neogene 'icehouse world'. Cyprus has extensive outcrops of Miocene to Pleistocene deep water sediments and provides an ideal setting to test the magnitude of climatic signals in tectonically active areas, and thus deduce the relative roles of climate and tectonics on sedimentation. Detailed sedimentary logging and biostratigraphical dating of the Miocene-age pelagic Pakhna Formation reveals that the formation can be divided into depositional sequences,bounded by hard grounds or erosion surfaces, and contains a distinct pattern of marl-chalk couplets. These sequences correlate, within the constraints of biostratigraphy to European and New Jersey Margin sequence chronostratigraphy. Three smaller scales of cyclicity are identified by stratigraphic time series analysis, and are likely to correspond to the 100 kyr, 41ky and ~20 ky Milankovitch cycles. Stable oxygen and carbon isotope analysis on pelagicforaminifera indicate the following climatic influences; (1) chalk-marl couplets probably record climatically controlled supply of terrigenous material; (2) a strong link between 818O maxima and sequence boundaries; and (3) the globally recognised 813C Monterey ExcursionIS present. The increasing abundance of tectonically derived Troodos material partially masks the climatically controlled sedimentation in the Pakhna Formation south of the Troodos massif. Rapid Troodos uplift during the Pliocene-Pleistocene is demonstrated by the high abundance of ophiolite derived clasts in the Khirokitia-Psematismenos submarine fan-complex. Here,graphic logging, and biostratigraphy suggests that the six cycles observed are likely to correlate to cycles identified in European sequence chronostratigraphy, though higher frequency,climatic cyclicity is obscured by the overprint of tectonic activity.
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Khodabakhsh, Saeed. "Pleistocene Laurentide Ice Sheet drainage into the Labrador Sea, sedimentary facies, depositional mechanisms, stratigraphy and significance of Heinrich events." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ30309.pdf.
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Khodabakhsh, Saeed. "Pleistocene Laurentide Ice Sheet drainage into the Labrador Sea : sedimentary facies, depositional mechanisms, stratigraphy and significance of Heinrich events." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=42067.
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On the basis of sedimentary structures and textures, six depositional facies have been identified in Labrador Slope, Rise and Basin cores. They include: (1) turbid-surface plume sediments (facies P; plumites) comprising 4% of the total length of the slope cores; (2) hemipelagic sediments (facies HI and H) with and without ice-rafted debris (IRD) (48% and 20% on the slope/rise and basin centre, respectively); (3) nepheloid-layer deposits (facies N; 9% on the slope); (4) contourites (facies C; 4% on the slope); (5) turbidite facies (30% on the slope and $>$40% on the levees of the Northwest Atlantic Mid-Ocean Channel, NAMOC) with three subfacies: thin-bedded silt and mud turbidites (T); turbidites with laminae of IRD (TI), and sand turbidites (MS); and (6) debris-flow facies (10% on the slope) with four subfacies: gravelly (D1), sandy silt (D2), thin bedded (D3) and sandy gravelly debris-flow deposits (D4).Facies P occurs on high-relief slope sections, deposited by buoyantly rising meltwater plumes entrained by the south-flowing Labrador Current. The high relief was caused by retrograde canyon erosion after deposition. Facies N is best developed and thickest on the slope and upper rise. It was deposited when sediment-laden meltwater from the Laurentide Ice Sheet with high concentrations of suspended sediment spread out in mid-water or along the bottom. Facies T occurs on the levees of the NAMOC and its tributaries. It originated from the remobilization of detrital carbonate-rich sediments on the slope south of the Hudson Strait. Extensive sand turbidites occur on a braided floodplain east of NAMOC. Deposition of sand turbidites by high-density turbidity currents, probably of sheet-flow type, resulted from bedload-rich meltwater discharges on the low-relief slope sector off the Hudson Strait. They may have been caused by subglacial-lake outburst flooding, which might be linked to Heinrich events. Facies C occurs on the lower slope to upper rise. Facies H is present in all parts of the basin but most abundant on the slope; together with facies T, it is the major facies in the intercanyon regions. Facies D is found mainly on low-relief slope sectors, in front and north of major glacier outlets. Debris-flow tongues in the slope canyons merge downslope forming an extensive stacked megadebris-flow deposit on the floodplain west of NAMOC. Facies D makes up $>$75% of the sediment thickness in the western floodplain cores.
Four types of Heinrich layers (HL) were identified. (Abstract shortened by UMI.)
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Beckvar, Nancy. "Stratigraphy, Taphonomy, and Fauna-Substrate Associations in a Gulf of California Pleistocene Marine Terrace Near Punta Chueca, Sonora, Mexico." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/249292.
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A richly fossiliferous Pleistocene terrace located near Punta Chueca, Sonora, Mexico, contains sediments that were deposited at the interface of an alluvial fan and shallow marine environment. Shell beds range from extremely dense fossil concentrations in sand, gravel, and cobble sized sediments to sparsely fossiliferous shell hashes. Three subenvironments were recognized: 1) shallow-subtidal to lower intertidal; 2) mid- to upper intertidal; and 3) supratidal. Shallow-subtidal to lower intertidal facies consist of shell beds with infaunal bivalves in life position, shell beds with fauna not in life position, and a Porites biostrome. Mid- to upper-intertidal facies include shell hash layers, and pebble and cobble lenses that are characterized by abundant autochthonous epi- faunal gastropods (i.e. limpets). Sparsely fossiliferous supratidal sands are overlain by Holocene alluvial fan deposits. Coarse conglomerates were not reworked by marine processes whereas finer conglomerates were, as evidenced by horizontal bedding and segregation of gravel and sand. The coarsest sediments - metamorphic cobbles - are relict and were probably derived from an earlier terrace. The following criteria were used to interpret the mode of shell bed formation: encrustation frequency, valve articulation, bivalve orientation, shell condition, and shell density (hardpart abundance). Storms played a major role in the formation of fossil concentrations. Four shell beds were interpreted as storm beds and one shell bed was interpreted as a condensed bed. Storm beds differ from condensed beds in having lower encrustation frequencies, higher percentages of articulated bivalves, and shells in very good condition. Association of hard-substrate faunas with gravel sediments and of infaunal molluscs with sand substrates suggests that little transport between habitats occurred. The high percentage of articulated valves, unworn appearance of most shells, predominance of concave-up oriented valves, and strong association of fauna with grain size all reflect a generally low energy environment, but one periodically disturbed by storm events.
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Vézina, Jennifer Lynn. "Stratigraphy and sedimentology of the Pleistocene Ironshore formation at Rogers Wreck Point, Grand Cayman, a 400 ka record of sea-level highstands." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq21215.pdf.
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