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Holocene

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Deglacial And Holocene Environmental Change Recorded In Lake Sediments From The Snowy Mountains, Kosciuszko National Park, Southeastern Australia, Emma J. Mickelson Jan 2024

Deglacial And Holocene Environmental Change Recorded In Lake Sediments From The Snowy Mountains, Kosciuszko National Park, Southeastern Australia, Emma J. Mickelson

WWU Graduate School Collection

The sediment record from Lake Albina, the Snowy Mountains, southeastern Australia suggests significant environmental change mostly reflecting shifts in climate from the LGM through the Holocene. Immediately following deglaciation, approximately 19.4 thousand cal ky BP, Lake Albina experienced cold and/or dry conditions with minimal vegetation in the catchment. Cooler conditions persisted with a slight increase in moisture throughout the Antarctic Cold Reversal (ACR; 14.7-13 cal ky BP) aligning closest with a strengthening of the Atlantic Meridional overturning circulation (AMOC) and a northward shift of the South Westerly Winds (SWW). Between 12.9-9.7 cal ky BP, Lake Albina recorded a climate reversal …


New Evidence For Holocene Activity Of The Northern Segment Of The Puqian-Qinglan Fault In Northern Hainan Province, Liu Huaguo, Li Feng, Jia Qichao, Wang Zhicheng, Zhang Pan, Lin Zhen, Zhang Jiehan, Shi Chunhua, Zhang Yanbo, Jia Wei, Li Changlong Dec 2023

New Evidence For Holocene Activity Of The Northern Segment Of The Puqian-Qinglan Fault In Northern Hainan Province, Liu Huaguo, Li Feng, Jia Qichao, Wang Zhicheng, Zhang Pan, Lin Zhen, Zhang Jiehan, Shi Chunhua, Zhang Yanbo, Jia Wei, Li Changlong

Coal Geology & Exploration

The Puqian-Qinglan fault, located in northern Hainan Province, is closely related to the judgment of the seismogenic structure of the Qiongshan M7½ earthquake in 1605. To accurately determine the latest activity characteristics of this fault, this study, adopting artificial shallow seismic exploration with large-tonnage seismic sources combined with small-spacing cross-well stratigraphic correlation, investigated the sedimentary geological conditions of the Quaternary basalt cover and significantly thick marine sand layers in northern Hainan Province through exploration at Qishantou and Dongzhai villages in the Sanjiang Town, Jiangdong New Area, Haikou. Key results are as follows: (1) the Puqian-Qinglan fault dislocates multiple marker …


Field Guide To Big Bone Lick, Kentucky: Birthplace Of American Vertebrate Paleontology, Glenn W. Storrs, H Gregory Mcdonald, Eric Scott, Robert A. Genheimer, Stanley E. Hedeen, Cameron E. Schwalbach Oct 2023

Field Guide To Big Bone Lick, Kentucky: Birthplace Of American Vertebrate Paleontology, Glenn W. Storrs, H Gregory Mcdonald, Eric Scott, Robert A. Genheimer, Stanley E. Hedeen, Cameron E. Schwalbach

Special Publication--KGS

Big Bone Lick is the birthplace of vertebrate paleontology in the Western Hemisphere and has a long and celebrated history in the exploration of the American colonial frontier and of the early United States. Notable European scientists of the 18th century such as Buffon, Cuvier, and Hunter discussed the fossils found there. Prominent Americans of the time, such as Boone, Washington, Franklin, and Jefferson are also part of the site’s history. It is the type locality for several extinct late Pleistocene megafaunal mammals, most notably the iconic American Mastodon, who were attracted to the area by salt licks dictated by …


Systemic Analyses Of Radiocarbon Ages Of Coexisting Planktonic Foraminifera, Jörg Lippold, Julia Gottschalk, Jean Lynch-Stieglitz, Matthew W. Schmidt, Sönke Szidat, Andre Bahr Jan 2023

Systemic Analyses Of Radiocarbon Ages Of Coexisting Planktonic Foraminifera, Jörg Lippold, Julia Gottschalk, Jean Lynch-Stieglitz, Matthew W. Schmidt, Sönke Szidat, Andre Bahr

OES Faculty Publications

We compare radiocarbon (14C) ages of coexisting planktonic foraminifera species from sediment cores VM12-107 and KNR166-2-26JPC from the Equatorial Atlantic Ocean for three time periods (Holocene, Heinrich Stadial 1, last glacial maximum). We find a maximum inter-species difference of 1200 14C yr. On average, the 14C ages deviate by ∼300 yr between Globigerinoides ruber and other species. In most cases, this exceeds the analytical uncertainty range of the measurements and thus renders the choice of species for generating age models as important as sample weight. While modern stratified water-column profiles imply an increase in 14C …


Sediment Delivery To Sustain The Ganges-Brahmaputra Delta Under Climate Change And Anthropogenic Impacts, Jessica L. Raff, Steven L. Goodbred Jr., Jennifer L. Pickering, Ryan S. Sincavage, John C. Ayers, Md. Saddam Hossain, Carol A. Wilson, Chris Paola, Michael S. Steckler, Dhiman R. Mondal, Jean-Louis Grimaud, Celine Jo Grall, Kimberly G. Rogers, Kazi Matin Ahmed, Syed Jo Grall, Kimberly G. Rogers, Kazi Matin Ahmed, Syed Humayun Akhter, Brandee N. Carlson, Elizabeth L. Chamberlain, Meagan Dejter, Jonathan M. Gilligan, Richard P. Hale, Mahfuzur R. Khan, Md. Golam Muktadir, Md. Munsur Rahman, Lauren A. Williams Jan 2023

Sediment Delivery To Sustain The Ganges-Brahmaputra Delta Under Climate Change And Anthropogenic Impacts, Jessica L. Raff, Steven L. Goodbred Jr., Jennifer L. Pickering, Ryan S. Sincavage, John C. Ayers, Md. Saddam Hossain, Carol A. Wilson, Chris Paola, Michael S. Steckler, Dhiman R. Mondal, Jean-Louis Grimaud, Celine Jo Grall, Kimberly G. Rogers, Kazi Matin Ahmed, Syed Jo Grall, Kimberly G. Rogers, Kazi Matin Ahmed, Syed Humayun Akhter, Brandee N. Carlson, Elizabeth L. Chamberlain, Meagan Dejter, Jonathan M. Gilligan, Richard P. Hale, Mahfuzur R. Khan, Md. Golam Muktadir, Md. Munsur Rahman, Lauren A. Williams

OES Faculty Publications

The principal nature-based solution for offsetting relative sea-level rise in the Ganges-Brahmaputra delta is the unabated delivery, dispersal, and deposition of the rivers’ ~1 billion-tonne annual sediment load. Recent hydrological transport modeling suggests that strengthening monsoon precipitation in the 21st century could increase this sediment delivery 34-60%; yet other studies demonstrate that sediment could decline 15-80% if planned dams and river diversions are fully implemented. We validate these modeled ranges by developing a comprehensive field-based sediment budget that quantifies the supply of Ganges-Brahmaputra river sediment under varying Holocene climate conditions. Our data reveal natural responses in sediment supply comparable to …


Micropaleontological Findings And Absolute Ages Mark The Termination Of The Last Glacial Maximum In The Eastern Mediterranean Region: New Electron Spin Resonance Data From Gediz Delta (Western Turkey), Eki̇n Gökçe Benli̇, Hülya Aslin, İsmai̇l İşi̇ntek, Bi̇rol Engi̇n, Berna Şengöçmen Geçki̇n Jan 2023

Micropaleontological Findings And Absolute Ages Mark The Termination Of The Last Glacial Maximum In The Eastern Mediterranean Region: New Electron Spin Resonance Data From Gediz Delta (Western Turkey), Eki̇n Gökçe Benli̇, Hülya Aslin, İsmai̇l İşi̇ntek, Bi̇rol Engi̇n, Berna Şengöçmen Geçki̇n

Turkish Journal of Earth Sciences

Sediments and fossil content of Gediz Delta (Eastern Aegean Sea-İzmir) were examined from the samples collected from three drilling cores from the west (seaward) to east (landward) of the delta. Each drilling core contains Quarternary marine deposits with a marine fauna of foraminifers, bivalves, gastropods, echinoids, and ostracods at the bottom and Quaternary continental delta deposits at the top. According to our Electron Spin Resonance (ESR) age model marine sediments of the Aegean Sea started to cover the western Gediz Delta area before 19.9 ka (thousand years). Following the Last Glacial Maximum (LGM), after the transgression due to deglaciation occurred …


Sub-Recent Microfauna Within Allogenic Sediments At The Bottom Of A Deep Cave, Njemica (Biokovo Mt., Croatia), Tomislav Kurečić, Valentina Hajek Tadesse, Lara Wacha, Marija Horvat, Nina Trinajstić, Ivan Mišur Nov 2022

Sub-Recent Microfauna Within Allogenic Sediments At The Bottom Of A Deep Cave, Njemica (Biokovo Mt., Croatia), Tomislav Kurečić, Valentina Hajek Tadesse, Lara Wacha, Marija Horvat, Nina Trinajstić, Ivan Mišur

International Journal of Speleology

Clastic sediments deposited at the bottom of the vertical, nearly 1000 m deep Njemica Cave (Biokovo Mountain, Croatia) were analysed. Owing to the vertical morphology of the cave, the occurrences of clastic sediments are sparse. Small, up to decimetre-thick, undisturbed sediment accumulations situated near the siphon lake revealed interesting palaeontological and mineralogical data. These data are used as a useful proxy for discussing depositional processes, the provenance of the sediments and paleo-habitats of the subterranean fauna.

The sub-recent assemblages of ostracods were discovered within the sediment, and they were shown to be correlative to the known endemic species in the …


Investigation Of Dead Ocean Quahogs (Arctica Islandica) Shells On The Mid-Atlantic Bight Continental Shelf, Alyssa Leclaire Aug 2022

Investigation Of Dead Ocean Quahogs (Arctica Islandica) Shells On The Mid-Atlantic Bight Continental Shelf, Alyssa Leclaire

Master's Theses

Ocean quahogs, Arctica islandica, are a long-lived, widely dispersed, biomass dominate in the Mid-Atlantic; therefore, quahog shells are valuable resources for studying climate change over time. Recently, dead ocean quahog shells were discovered south and inshore of the present biogeographic range of this animal. The presence of ocean quahog shells outside the current range is presumably a consequence of past regressions and transgressions of the Cold Pool, the bottom-trapped, cool body of water that allows boreal animals to live at lower latitudes. Dead ocean quahog shells were collected offshore of the DelMarVa Peninsula then radiocarbon-dated, evaluated for taphonomic condition, …


Characterization Of Quaternary Stratigraphy In The Mississippi Sound To Evaluate The Influence Of Geologic Heterogeneity On Submarine Groundwater Transport And Discharge, Zachary Peoples May 2022

Characterization Of Quaternary Stratigraphy In The Mississippi Sound To Evaluate The Influence Of Geologic Heterogeneity On Submarine Groundwater Transport And Discharge, Zachary Peoples

Theses and Dissertations

Submarine Groundwater Discharge (SGD) through seafloor sediments is gaining recognition as an important component of coastal water quality. Stratigraphic features creating geologic heterogeneity, such as incised paleochannels, may influence preferential pathways for SGD. The central Mississippi Sound is underlain by paleochannels that were incised into Pleistocene sediments while the area was subaerially exposed during the last glacial maximum and are now buried by transgressive Holocene deposits. In this thesis, newly collected chirp, previously published seismic reflection, and sediment core data are used to characterize the three-dimensional structure of the Holocene-Pleistocene contact. Results indicate that Pleistocene paleochannels cross-cut the study area, …


Holocene Sedimentary History Of South Danamandıra Lake: A Peatland In West Of İstanbul, Çatalca Peninsula, Nw Turkey, Özlem Makaroğlu, Melda Küçükdemi̇rci̇, Nurgül Karlioğlu, Dursun Acar, Ali̇ Gürel, Rüya Yilmaz Dağdevi̇ren, Nuretti̇n Yakupoğlu, Asen Sabuncu, Damla Şahi̇n Altun, Mustafa Ömer Karaöz, Memet Namik Çağatay Jan 2022

Holocene Sedimentary History Of South Danamandıra Lake: A Peatland In West Of İstanbul, Çatalca Peninsula, Nw Turkey, Özlem Makaroğlu, Melda Küçükdemi̇rci̇, Nurgül Karlioğlu, Dursun Acar, Ali̇ Gürel, Rüya Yilmaz Dağdevi̇ren, Nuretti̇n Yakupoğlu, Asen Sabuncu, Damla Şahi̇n Altun, Mustafa Ömer Karaöz, Memet Namik Çağatay

Turkish Journal of Earth Sciences

This study investigates the sedimentological evolution of the South Danamandıra Lake (SDL) lake in Çatalca Peninsula, 70 km west of İstanbul, using Georadar data and multiproxy analyses of five sediment cores. The lake is a 1.3-m deep, endorheic freshwater peatland, heavily colonised by common reed (Phragmites sp.). The multiproxy core investigations include a lithological core description and environmental magnetism, physical properties (gamma density and magnetic susceptibility), geochemical elemental, pollen and radiocarbon dating analyses. The lithological sequence in the lake consists of an upper peat unit and a lower sand-silt-clay unit. The peat unit is characterized by lower magnetic susceptibility, density …


Unearthing The Effects Of European-American Settlement On A Northeast Ohio Kettle Lake Through Diatom Stratigraphy, Justine Paul A. Berina Jan 2022

Unearthing The Effects Of European-American Settlement On A Northeast Ohio Kettle Lake Through Diatom Stratigraphy, Justine Paul A. Berina

Senior Independent Study Theses

Recently, wetland conservation has highlighted the necessity for assessing limnological changes following European-American settlement. A prior study at Brown's Lake (northeast Ohio) identified a stratigraphic sequence that shows an abrupt transition from organic-rich muds to several centimeters of a bright loess layer, then a recovery to organic-rich sediments near the top. Based on 210Pb dates, the loess deposition occurred before 1846 CE, when a growing population cleared trees and farmed intensively. Likewise, organics had recovered after 1950 CE, when people abandoned farmland and practiced conservation tillage. However, the effects of settlement on limnology are poorly known. Diatoms (microscopic algae; …


Reconstructing Deglacial And Holocene Climatic And Environmental Change In The Snowy Mountains Of Southeast Australia, Aidan Warner Burdick Jan 2022

Reconstructing Deglacial And Holocene Climatic And Environmental Change In The Snowy Mountains Of Southeast Australia, Aidan Warner Burdick

WWU Graduate School Collection

Multi-proxy, long-term records of deglacial and Holocene climatic and environmental change in southeast Australia are rare, leaving the region a gap in local and large-scale synoptic climate reconstructions. The Snowy Mountains include the highest and coldest regions of mainland Australia and were the only part of the mainland that was glaciated during the late Pleistocene. Lakes formed by the glaciers have provided continuous sediment traps since glacial retreat following the Last Glacial Maximum. In this report, I reconstruct the maximum ice extents of glaciers during the last glacial period and estimate their equilibrium line altitudes, revising the work of Barrows …


The Impacts Of Mid-Holocene Warming On Water Quality In A Southwestern Ontario Kettle Pond, Morgan E. Peicheff Aug 2021

The Impacts Of Mid-Holocene Warming On Water Quality In A Southwestern Ontario Kettle Pond, Morgan E. Peicheff

Undergraduate Student Research Internships Conference

No abstract provided.


Past Ice-Ocean Interactions On The Sabrina Coast Shelf, East Antarctica: Deglacial To Recent Paleoenvironmental Insights From Marine Sediments, Kara J. Vadman May 2021

Past Ice-Ocean Interactions On The Sabrina Coast Shelf, East Antarctica: Deglacial To Recent Paleoenvironmental Insights From Marine Sediments, Kara J. Vadman

USF Tampa Graduate Theses and Dissertations

The East Antarctic Ice Sheet (EAIS) contains ~53 meters of sea level equivalent (SLE) ice, and observations suggest it is sensitive to ongoing and past climate change. The EAIS has traditionally been considered insensitive to climate perturbations because it is largely grounded above sea level. However, aerogeophysical surveys, oceanographic observations, and models indicate that large areas of the EAIS are grounded below sea level and contain 19.2 m SLE. Marine-based parts of the EAIS are thought to be located on inland-sloping beds that drain through marine terminating outlet glaciers, indicating large areas of the EAIS may be more sensitive to …


Glacial Geology Of Readfield Maine, Bryer Carlson Apr 2021

Glacial Geology Of Readfield Maine, Bryer Carlson

Michael D. Wilson Symposium

This poster explores the glacial geology in the town of Readfield Maine. With the use of GPR (ground penetrating radar), LiDar imaging and the State's surficial geology maps, evidence for a specific glacial feature called an "esker" was sought out and collected.


Holocene Records Of Nebraska Mammals, Hugh H. Genoways Mar 2021

Holocene Records Of Nebraska Mammals, Hugh H. Genoways

Zea E-Books Collection

A survey of the archeological and paleontological literature allowed a compilation of Holocene records of mammals in Nebraska. This survey identified Holocene records from 338 sites in 62 of the 93 Nebraska counties. These counties were located throughout state, but there was a concentration of sites in southwestern Nebraska where there were 27 fossil sites in Frontier County and 22 in Harlan County. Fossils sites were underrepresented in the Sand Hills region. Records of fossil mammals covered the entire Holocene period from 13,000 years ago until AD 1850. A minimum of 57 species (with eight additional species potentially present) representing …


Long-Term African Dust Delivery To The Eastern Atlantic Ocean From The Sahara And Sahel Regions: Evidence From Quaternary Paleosols On The Canary Islands, Spain, Daniel R. Muhs, Joaquín Meco, James R. Budahn, Gary L. Skipp, Kathleen R. Simmons, Matthew C. Baddock, Juan F. Betancourt, Alejandro Lomoschitz Jan 2021

Long-Term African Dust Delivery To The Eastern Atlantic Ocean From The Sahara And Sahel Regions: Evidence From Quaternary Paleosols On The Canary Islands, Spain, Daniel R. Muhs, Joaquín Meco, James R. Budahn, Gary L. Skipp, Kathleen R. Simmons, Matthew C. Baddock, Juan F. Betancourt, Alejandro Lomoschitz

United States Geological Survey: Staff Publications

Africa is the most important source of dust in the world today and dust storms from that continent frequently deposit sediment on the nearby Canary Islands. Many investigators have inferred African dust inputs to Canary Islands paleosols based only on the presence of quartz. However, some local rocks do contain this mineral, so quartz alone is insufficient proof of dust deposition. Further, it is not known whether the Sahara Desert or the Sahel region is more important as a dust source. We address these issues by study of sequences of Pleistocene aeolian sands on the islands of Lanzarote and Fuerteventura. …


A Holocene Paleomagnetic Record From Küçükçekmece Lagoon, Nw Turkey, Özlem Makaroğlu Jan 2021

A Holocene Paleomagnetic Record From Küçükçekmece Lagoon, Nw Turkey, Özlem Makaroğlu

Turkish Journal of Earth Sciences

Lake sediments are very useful for providing high-resolution records of geomagnetic field variations, especially for the Holocene period. We present high-resolution paleomagnetic records from three cores (KCL12P1, P2, and P3) recovered from Küçükçekmece Lagoon, located at the northern shoreline of the Sea of Marmara, Turkey. The cores were subjected to a comprehensive paleomagnetic and rock magnetic investigation using oriented samples. According to the age-depth model, based on radiocarbon dating and X-ray fluorescence-derived Ca/Ti element ratios, tuned to available oxygen isotope records based on an absolute calendar-year time-scale, we obtained a new paleomagnetic record for the last 3800 years. Low paleointensities …


Migration Of The Frozen/Melted Basal Boundary Linked To ~100 Kilometers Of Ice Margin Retreat, Western Greenland Ice Sheet, Aidan Ripley Stansberry Jan 2021

Migration Of The Frozen/Melted Basal Boundary Linked To ~100 Kilometers Of Ice Margin Retreat, Western Greenland Ice Sheet, Aidan Ripley Stansberry

Graduate Student Theses, Dissertations, & Professional Papers

The geometry and thermal structure of western Greenland ice sheet have evolved over the last 11 kyr in response to Holocene climate. Evolution of the frozen and melted fractions of the bed associated with the ice sheet retreat over this time frame remains unclear. We address this question using a thermo-mechanically coupled flowline model to simulate a 11 kyr period of ice sheet retreat in west central Greenland. Our transient flow-line modeling includes high order stresses, thermally active bedrock, a well-informed climate that is constrained by an established record of ice margin retreat. We partition the transient heat balance into …


Geomorphic History Of The Grand Staircase Region Of The Colorado Plateau: Understanding Arroyo Cut-Fill Dynamics, Erosion Rates, And Wildfire, Kerry E. Riley Aug 2020

Geomorphic History Of The Grand Staircase Region Of The Colorado Plateau: Understanding Arroyo Cut-Fill Dynamics, Erosion Rates, And Wildfire, Kerry E. Riley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Most streams in the southwestern United States do not flow all year, and given their delicate balance of sediment and water flow, they are sensitive to climate change. At the turn of the 20th century, many streams in the Southwest rapidly incised into their floodplains, forming arroyos with a channel entrenched into near-vertical channel banks mostly composed of sand and mud. This dissertation investigates past changes in watersheds draining the Grand Staircase region in southern Utah with the goal of understanding how changes in climate and sediment influence these types of streams. Results show sediment supply is highly variable across …


Refining Interpretations Of A Deglacial Record In Gulf Of Mexico Marine Sediment Cores Using Foraminifera C-14 Dates And Multi-Proxy Sediment Analyses, Lindsey R. Monito May 2020

Refining Interpretations Of A Deglacial Record In Gulf Of Mexico Marine Sediment Cores Using Foraminifera C-14 Dates And Multi-Proxy Sediment Analyses, Lindsey R. Monito

Senior Honors Projects, 2020-current

The upper fourteen sections of three cores recovered from the International Marine Past Global Changes Study (IMAGES) VIII/Paleoceanography of the Atlantic and Geochemistry (PAGE) 127 expedition of 2002, are stratigraphic records of the climate and provenance variations that influenced sediment deposition in the Gulf of Mexico during the Pleistocene and Holocene. Though originally cored by the USGS for gas hydrate investigations, cores MD02-2535, MD02-2555, and MD02-2560 have been repurposed for undergraduate course-based paleoclimate research at JMU. Shipboard interpretations of the color reflectance data for these cores suggested that two dark stratigraphic intervals present in all of the cores were regional …


Nearshore Sedimentology Of Eroding Microtidal Estuaries: Bon Secour Bay, Alabama And Perdido Bay, Florida, Jennifer Simpson May 2020

Nearshore Sedimentology Of Eroding Microtidal Estuaries: Bon Secour Bay, Alabama And Perdido Bay, Florida, Jennifer Simpson

Master's Theses

Estuarine shorelines along the northern Gulf of Mexico are dynamic geologic settings that provide numerous ecological and economic benefits. By definition, estuaries are semi-enclosed bodies of water that receive sediment from two sources: (1) fluvial systems feeding into the estuary and (2) sediment transported by wave action and tidal currents from adjacent marine sources. Erosion of estuarine shorelines resulting from rising sea level, storm impact, and anthropogenic influence has been increasingly evident in the microtidal Gulf Coast over recent decades. This study collects quantitative and qualitative data to better understand sedimentary dynamics associated with contemporary estuarine shoreline erosion in Bon …


A Multi-Method Investigation Of The Modern Sedimentation And Late Holocene Paleolimnology Of June Lake (Mono County, Ca), And A Survey-Based Analysis Of Ninth Graders’ Attitudes Towards Geology, Eva Lyon Jan 2020

A Multi-Method Investigation Of The Modern Sedimentation And Late Holocene Paleolimnology Of June Lake (Mono County, Ca), And A Survey-Based Analysis Of Ninth Graders’ Attitudes Towards Geology, Eva Lyon

Theses and Dissertations--Earth and Environmental Sciences

Three distinct manuscripts comprise this dissertation. The first analyzes the modern sedimentary basin of June Lake, a small glacial lake in the eastern Sierra Nevada of California (USA) using a number of data sets, including bathymetry, surface sediment composition, and seismic stratigraphy. The seismic survey revealed sublacustrine morphological features that suggest the basin originated due to ice scour, as well as four acoustically distinct stratigraphic units that reflect the history of sedimentation following glacial scouring. Corroborating the seismic record, sediment cores from the youngest unit are composed of hemipelagically deposited, organic-rich, laminated diatomaceous oozes alternating with coarse tephra beds. The …


Sedimentological Properties And Depositional Environments Of The Holocene Sequence In Yenikapı, İstanbul, Meltem Sezerer Bulut, M.Namık Yalçin, Oya Algan Dec 2019

Sedimentological Properties And Depositional Environments Of The Holocene Sequence In Yenikapı, İstanbul, Meltem Sezerer Bulut, M.Namık Yalçin, Oya Algan

Bulletin of the Mineral Research and Exploration

During the salvage excavations in the area of the former Theodosian harbor in Yenikapı-İstanbul several ship wrecks from the Byzantine period, archaeological objects from different periods and a Holocene aged sedimentary sequence have been uncovered. In this study the lithological, lithostratigraphical and facies properties of the Holocene sequence are investigated in detail and its depositional environment is determined. For this purpose along four profiles (S1, S2, S3, S4) 14 different sections of a total thickness of 17.75 m are studied and 100 samples are collected. The grain size distribution of the samples is defined by sieve and sedigraph analysis and …


Holocene And Last Interglacial Climate Of The Faroe Islands From Sedimentary Plant Wax Hydrogen And Carbon Isotopes, Lorelei Curtin, William J. D'Andrea, Nicholas Balascio, Genevieve Pugsley, Gregory De Wet, Raymond Bradley Nov 2019

Holocene And Last Interglacial Climate Of The Faroe Islands From Sedimentary Plant Wax Hydrogen And Carbon Isotopes, Lorelei Curtin, William J. D'Andrea, Nicholas Balascio, Genevieve Pugsley, Gregory De Wet, Raymond Bradley

Geosciences: Faculty Publications

The Last Interglacial period (LIG) is Earth's most recent globally warm period and is analogous in some ways to projected future global warming. However, questions remain regarding the state of the climate during the LIG in the North Atlantic, a region that is extremely sensitive to changes in oceanic and atmospheric circulation. Here, we present hydrogen and carbon isotope (δD and δ13C) records from a suite of plant wax biomarkers preserved in Holocene and LIG lacustrine sediments from the North Atlantic Faroe Islands and interpret them as qualitative proxies for temperature and hydroclimate variability. These data are used to directly …


Pacific Southwest United States Holocene Droughts And Pluvials Inferred From Sediment Δ18o (Calcite) And Grain Size Data (Lake Elsinore, California), Matthew E.C. Kirby, William Paul Patterson, Matthew Lachniet, James A. Noblet, Michael A. Anderson, Kevin Nichols, Judith Avila Apr 2019

Pacific Southwest United States Holocene Droughts And Pluvials Inferred From Sediment Δ18o (Calcite) And Grain Size Data (Lake Elsinore, California), Matthew E.C. Kirby, William Paul Patterson, Matthew Lachniet, James A. Noblet, Michael A. Anderson, Kevin Nichols, Judith Avila

Geoscience Faculty Research

Records of past climate can inform us on the natural range and mechanisms of climate change. In the arid Pacific southwestern United States (PSW), which includes southern California, there exist a variety of Holocene records that can be used to infer past winter conditions (moisture and/or temperature). Holocene records of summer climate, however, are rare from the PSW. In the future, climate changes due to anthropogenic forcing are expected to increase the severity of drought in the already water stressed PSW. Hot droughts are of considerable concern as summer temperatures rise. As a result, understanding how summer conditions changed in …


The Influence Of Fetch On The Holocene Thermal Structure Of Hidden Lake, Glacier National Park, Jeffery R. Stone, Jasmine E. Saros, Trisha L. Spanbauer Feb 2019

The Influence Of Fetch On The Holocene Thermal Structure Of Hidden Lake, Glacier National Park, Jeffery R. Stone, Jasmine E. Saros, Trisha L. Spanbauer

Department of Earth and Atmospheric Sciences: Faculty Publications

We use three-dimensional modeling of the basin of Hidden Lake, Montana, to assess the influence of effective fetch on diatom-inferred changes in mixing depths throughout the Holocene. The basin of Hidden Lake is characterized by a complex morphometry; for example, three-dimensional modeling of the lake basin indicates that a decrease in lake level of 2 m would result in complete isolation of the deepest part of the lake basin from the rest of the lake. Our model suggests that small changes in the lake surface elevation at Hidden Lake would produce threshold-like responses in effective fetch, which in turn would …


Diatom-Inferred Records Of Paleolimnological Variability And Continental Hydrothermal Activity In Yellowstone National Park, Usa, Sabrina Brown Jan 2019

Diatom-Inferred Records Of Paleolimnological Variability And Continental Hydrothermal Activity In Yellowstone National Park, Usa, Sabrina Brown

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Fossil diatoms were used to reconstruct paleoclimatic and hydrothermal conditions in Yellowstone National Park. First, an extensive literature review summarizes the current state of knowledge about eukaryotic organisms characteristic of continental hydrothermal environments. Eukaryotes in hydrothermal systems can live at extremes of acidity (pH 9.0), and at moderately high temperatures (<62 >C). Silicate and carbonate precipitation in continental hydrothermal environments is mediated by eukaryotic organisms, which are important members of biofilm communities.

A case study of alkaline-chloride sinter deposits in Yellowstone Lake and the Upper Geyser Basin inferred in-situ diatom growth rather than post-depositional accumulation of valves settling from …


Peatlands And Histosols In Canaan Valley National Wildlife Refuge, West Virginia, Mitzy Leigh Schaney Jan 2019

Peatlands And Histosols In Canaan Valley National Wildlife Refuge, West Virginia, Mitzy Leigh Schaney

Graduate Theses, Dissertations, and Problem Reports

Canaan Valley in West Virginia contains a greater area of peatlands than any other locality in the mid-Atlantic Highlands. Extensive fieldwork focused on peat stratigraphy and pedology, combined with high-resolution radiocarbon dating, was used to evaluate five peatlands within Canaan Valley National Wildlife Refuge (CVNWR) in the central Appalachian Mountains. One hundred soil cores were profiled and described, 30 with laboratory data, including 52 radiocarbon dates. Calibrated basal peat dates among the five mapped peatlands indicate a late Pleistocene timeframe for the onset of peat genesis, ranging from ~18,600 to ~15,200 cal yr BP. The dates for peat initiation are …


Late Quaternary Landscape Evolution Of The Southern Marmara Region:Paleogeographic Implications For Settlements, Nw Turkey, Ni̇zametti̇n Kazanci, Zeynep Ergun, Kaan İren, Suzanne A. Leroy, Sonay Boyraz Aslan, Mehmet Sali̇m Öncel, Koray Koç, Alper Gürbüz Jan 2019

Late Quaternary Landscape Evolution Of The Southern Marmara Region:Paleogeographic Implications For Settlements, Nw Turkey, Ni̇zametti̇n Kazanci, Zeynep Ergun, Kaan İren, Suzanne A. Leroy, Sonay Boyraz Aslan, Mehmet Sali̇m Öncel, Koray Koç, Alper Gürbüz

Turkish Journal of Earth Sciences

This study presents the late Quaternary evolution of the southern Marmara region in northwestern Turkey and discusses the suitability of the area for settlements. It is based on interpretation of sediment analyses together with radiometric dates obtained from drilling cores. As three-fourths of the southern Marmara region (ca. 30,000 km2) is covered by the Susurluk Drainage Basin (SDB), the study focuses on this basin. The SDB has a concave surface morphology dipping northward, with highlands in the south (ca. 1300-1700 m a.s.l.) and lowlands in the north (ca. 0-250 a.s.l.). Lake Manyas, Lake Ulubat, and south-north flowing rivers, together with …