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Showing 1 to 20 of 20 for “"paleoenvironmental reconstruction"”.
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Late Holocene Paleoenvironmental Reconstruction in Barbados
… measurements. This study presents a paleoclimate reconstruction for the late Holocene on Barbados using stable and radiogenic isotope ratios in speleothem lamina as proxies. In addition, it introduces the use of novel mineralogical analyses using Raman spectroscopy and large chamber-scanning …
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Paleoenvironmental Reconstruction of a Coastal Lagoon in Southwestern Dominican Republic
… the potential for paleotempestology and other paleoenvironmental reconstructions. Three AMS 14C dates indicate that the lake is ~1100 years in age. Sediment analyses revealed three major events that correlate with bands of uncharacteristic sediment composition and particle size at 74–77.5 cm, …
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Palynology of acid-saline lakes of western Australiabiostratigraphy and paleoenvironmental reconstruction
"Lakes are excellent repositories of fossils and sedimentary features that provide clues to past climatic and geologic events. Sediments from four cores drilled in Lake Aerodrome (LA1-09, LA2-09) and Lake Brown (LB1-09, LB2-09), two of the hundreds of ephemeral lakes in southern Western Australia, …
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Paleoenvironmental reconstruction of late quaternary lacustrine sediments (Seibold Site) in southeastern North Dakota
<p>The Seibold Site on the Missouri Coteau in northwest Stutsman County, North Dakota, contains a late Quaternary lacustrine deposit with a spectaculary preserved and diverse biota; more than 150 species occur, of which the mollusks and fish are figured and discussed in detail in this study. The …
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A late Holocene paleoenvironmental reconstruction of a coastal lake in northeastern Dominican Republic
… of increasing interest, long-term environmental reconstructions from lakes on the Atlantic side of the Caribbean islands are lacking. Laguna Limon is a freshwater lake in the El Seibo province of northeastern Dominican Republic. We collected a 315-cm sediment core from the center of the lake to …
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CENOZOIC EXTENSION OF THE LAKE TANGANYIKA RIFT, EAST AFRICA: STRUCTURES, TECTONOSTRATIGRAPHY AND PALEOENVIRONMENTAL RECONSTRUCTION
<p>Active continental rifts are ideal sites for understanding the break-up of continents, and long-lived rift lake environments are known as important reservoirs for endemic communities and biodiversity. The sedimentary fill of extensional continental rifts within the East Africa Rift System (EARS) …
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Paleoenvironmental Reconstruction of the Late Cretaceous Eastern Gulf Coastal Plain in Georgia and Alabama
<p>The present study reconstructs the regional paleoenvironment (particularly paleoclimate) of the Late Cretaceous Eastern Gulf Coastal Plain of Georgia and Alabama using paleobotanical, paleoecological and geochemical methods in order to evaluate the Late Cretaceous climate of the Southeastern …
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A multiproxy paleoenvironmental reconstruction of Late Quaternary marine sediments: Sunda Shelf, Southern South China Sea
… margins of error for late Pleistocene sea-level reconstruction and vertical crustal movement post-deposition from isostatic adjustment or tectonic activity.
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A paleoenvironmental reconstruction of the Elands Bay area using carbon and nitrogen isotopes in tortoise bone
… or bowsprit tortoise) bone collagen as a paleoenvironmental proxy, to augment the limited range of proxies preserved in Southern Africa. δ¹³C and δ¹⁵N were measured in 76 archaeological tortoises from Elands Bay Cave and nearby Tortoise Cave. The samples range in age from the late Holocene …
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Paleoenvironmental Reconstruction of an Upper Ordovician Rocky Shoreline: The Lindsay Formation of Heywood and Partridge Islands, Ontario
The islands of Heywood and Partridge, located northeast of Manitoulin Island in Georgian Bay, Ontario, preserve a major unconformity between the Paleoproterozoic Bar River and Lorrain Formation quartz arenite and Upper Ordovician Lindsay Formation carbonate and mudrock. The Lindsay Formation strata …
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Paleoenvironmental reconstruction based on palynological and palynofacies analyses of the Aptian-Albian succession in the Sergipe Basin, northeastern Brazil
… two wells in the Sergipe Basin with the aim of reconstruction the paleoenvironments of the upper Aptian-middle Albian interval. Altogether 19 species of spores, 31 species of pollen grains, 20 species of dinocysts were identified. Moreover, one genus of Acritarcha and one genus of fresh-water …
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Ichnology and sedimentology of large tetrapod burrows in the latest Early Triassic Katberg Formation, south-eastern main Karoo Basin, South Africa
… processes are important in ichnology and paleoenvironmental reconstruction. The analyses have therefore been undertaken through a multidisciplinary approach based on ichnological, sedimentological, petrographical, stratigraphic and paleontological evidence, gathered both in the field and …
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Carbon and sulfur isotopic constraints on Ediacaran biogeochemical processes, Huqf supergroups, Sultanate of Oman
… perturbations to the carbon and sulfur cycles. Paleoenvironmental reconstruction used the carbon and sulfur isotopic composition of sedimentary minerals and organic matter, supplemented by geochemical and molecular biomarker proxies, of strata from the Huqf Supergroup, Sultanate of Oman. Within …
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Holocene Palynology of the Gulf of Papua, Papua New Guinea: Using Modern Palynomorph Distribution to Better Constrain Paleoenvironmental Changes
… phase of this project (Chapter 4) includes a paleoenvironmental reconstruction of the last ~14.5 kyr in the GoP. Three long cores (MD-50, MV-41, MV-46) were selected for this analysis. Changes in palynomorph assemblages allow delineation of four major climate intervals from 14.5 kyr to …
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Molecular studies of the sources and significance of archaeal lipids in the oceans
… This finding has important implications for paleoenvironmental proxies reliant upon GDGTs. To investigate the effects of organic matter and bicarbonate + ammonia amendments on archaeal tetraether lipids and microbial community composition, I conducted large scale microcosm experiments. …
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Quantifying periods of diffusion in marine and nonmarine vertebrate fossils using rare earth elements
… for using post-mortem REE/TE/Isotopes for paleoenvironmental reconstruction. Previous studies of soft tissue preservation in fossilized bone have inferred shorter periods of diffusion and suggested that the rate of diffusion must outpace the rate of decay. Diffusion periods in bone from …
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Lake Sediment-Based Reconstructions of Late-Holocene Lowland Environments of Dominican Republic and Barbuda, Northern Caribbean
Questions remain regarding the impacts of late-Holocene human activities and environmental change on landscapes of the Caribbean islands. This dissertation examined the long-term environmental history of two sites in the northern Caribbean primarily through the analysis of proxy data sources …
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Reconstruction of the Late and Mid-Pleistocene climate and landscape history in SE-Central Europe - A paleopedological and geochemical multi-proxy approach in loess-paleosol studies.
… chronostratigraphy and iii) to contribute to the reconstruction of the Mid- and Late Pleistocene climate and landscape history of the region by a paleopedological – geochemical multi-proxy approach. Furthermore, methodological investigations aim to evaluate the validity of various …
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The sedimentary record of seafloor uplift
… The results have broad implications for paleoenvironmental reconstructions, basin evolution models, and geohazard assessments in both modern and ancient marine settings.
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LATE MIOCENE AND PLIOCENE PALEOCEANOGRAPHY OF THE LOW LATITUDE NORTHERN HEMISPHERE AND ITS IMPLICATIONS FOR FUTURE CLIMATE CHANGE
… into its present form. This study provides a reconstruction of sea surface temperature (SST), ocean circulation, and thermal structure of the LL eastern Pacific and North Atlantic based upon the compilation of proxy data derived from planktic foraminifer assemblages and geochemical techniques. …