scholarly journals Data report: revised Pleistocene sediment splice for Site U1457, IODP Expedition 355

2019 ◽  
Author(s):  
M. Lyle ◽  
R. Saraswat
Keyword(s):  
Pleistocene Sediment

scholarly journals Pleistocene sediment DNA reveals hominin and faunal turnovers at Denisova Cave

Nature ◽  
2021 ◽  
Author(s):  
Elena I. Zavala ◽  
Zenobia Jacobs ◽  
Benjamin Vernot ◽  
Michael V. Shunkov ◽  
Maxim B. Kozlikin ◽  
...  
Keyword(s):  
Contact Zone ◽  
Stone Tools ◽  
Environmental Context ◽  
Modern Human ◽  
Middle Palaeolithic ◽  
Upper Palaeolithic ◽  
Mt Dna ◽  
Southern Siberia ◽  
Sediment Samples ◽  
Pleistocene Sediment

AbstractDenisova Cave in southern Siberia is the type locality of the Denisovans, an archaic hominin group who were related to Neanderthals1–4. The dozen hominin remains recovered from the deposits also include Neanderthals5,6 and the child of a Neanderthal and a Denisovan7, which suggests that Denisova Cave was a contact zone between these archaic hominins. However, uncertainties persist about the order in which these groups appeared at the site, the timing and environmental context of hominin occupation, and the association of particular hominin groups with archaeological assemblages5,8–11. Here we report the analysis of DNA from 728 sediment samples that were collected in a grid-like manner from layers dating to the Pleistocene epoch. We retrieved ancient faunal and hominin mitochondrial (mt)DNA from 685 and 175 samples, respectively. The earliest evidence for hominin mtDNA is of Denisovans, and is associated with early Middle Palaeolithic stone tools that were deposited approximately 250,000 to 170,000 years ago; Neanderthal mtDNA first appears towards the end of this period. We detect a turnover in the mtDNA of Denisovans that coincides with changes in the composition of faunal mtDNA, and evidence that Denisovans and Neanderthals occupied the site repeatedly—possibly until, or after, the onset of the Initial Upper Palaeolithic at least 45,000 years ago, when modern human mtDNA is first recorded in the sediments.

scholarly journals Pleistocene sediment offloading and the global sulfur cycle

2015 ◽  
Vol 12 (10) ◽  
pp. 3043-3060 ◽  
Author(s):  
S. Markovic ◽  
A. Paytan ◽  
U. G. Wortmann
Keyword(s):  
Sea Level ◽  
Considerable Increase ◽  
Sediment Accumulation ◽  
Sulfur Cycle ◽  
Sea Level Fluctuations ◽  
Sediment Budgets ◽  
Shelf Sediment ◽  
Continental Shelves ◽  
Shelf Sediments ◽  
Pleistocene Sediment

Abstract. Quaternary sea level fluctuations have greatly affected the sediment budgets of the continental shelves. Previous studies suggested that this caused a considerable increase in the net loss of shelf sediments. Since sediment accumulation and erosion are closely tied to the formation and re-oxidation of pyrite, we use a high-resolution record of sulfur isotope ratios (34S / 32S) of marine sulfate to evaluate the implications of the so-called "shelf sediment offloading" on the global sulfur cycle. Modeling of our δ34S record suggests that erosion during sea level lowstands was only partly compensated by increased sedimentation during times of rising sea level and sea level highstands. Furthermore, our data suggests that shelf systems reached a new equilibrium state about 700 ka, which considerably slowed or terminated shelf sediment offloading.

scholarly journals Isotopic reconstruction of Proboscidean habitats and diets on enigmatic island of Sulawesi

2021 ◽  
Vol 47 (3) ◽  
pp. 79-80
Author(s):  
Mika Rizki Puspaningrum ◽  
Allan R. Chivas ◽  
Iwan Kurniawan ◽  
Unggul P. Wibowo ◽  
Yahdi Zaim ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Southeast Asia ◽  
Stable Isotope Analysis ◽  
Isotope Analysis ◽  
Early Pleistocene ◽  
Stable Carbon ◽  
Faunal Assemblage ◽  
Biogeographic History ◽  
Closed Canopy ◽  
Pleistocene Sediment

Sulawesi is known for its complex geological and biogeographic history, which is reflected in their extinct and extant faunal assemblage. Evidence of oldest terrestrial fauna in Sulawesi was found in the Early Pleistocene sediment and evolved since then. Despite being mostly isolated from the mainland Southeast Asia; four successive Proboscidean taxa have been found from the southern part of the island. The four taxa are: Stegoloxodon celebensis, Stegodon sompoensis, Stegodon sp. B, and cf. Palaeoloxodon namadicus, in which respective taxa are included in successive faunal stages. The aim of this research is to reconstruct the diet and palaeoenvironment of these Proboscidean taxa by incorporating stable isotope analysis with the fossil faunal record, geology, and stratigraphy. Stable carbon (δ13C) and oxygen (δ18O) isotope analysis were especially used in this study. Our result suggests that Stegoloxodon celebensis and Stegodon sompoensis were flexible feeders and were able to adapt to different niches, from closed canopy forest to open vegetation, while the diets of Stegodon sp. B, Celebochoerus heekereni and cf. Palaeoloxodon namadicus suggest that they were more specialized.

scholarly journals Pleistocene sediment offloading and the global sulfur cycle

2015 ◽  
Vol 12 (2) ◽  
pp. 1205-1245 ◽  
Author(s):  
S. Markovic ◽  
A. Paytan ◽  
U. G. Wortmann
Keyword(s):  
Sea Level ◽  
Considerable Increase ◽  
Sediment Accumulation ◽  
Sulfur Cycle ◽  
Sea Level Fluctuations ◽  
Sediment Budgets ◽  
Shelf Sediment ◽  
Continental Shelves ◽  
Shelf Sediments ◽  
Pleistocene Sediment

Abstract. Quaternary sea level fluctuations have greatly affected the sediment budgets of the continental shelves. Previous studies suggested that this caused a considerable increase in the net loss of shelf sediments. Since sediment accumulation and erosion are closely tied to the formation and re-oxidation of pyrite, we use a high resolution record of sulfur isotope ratios (34S / 32S) of marine sulfate to evaluate the implications of the so called "shelf sediment offloading" on the global sulfur cycle. Modeling of our δ34S record suggests that erosion during sea level lowstands was only partly compensated by increased sedimentation during times of rising sea level and sea level highstands. Furthermore, our data suggests that shelf systems reached a new equilibrium state about 700 kyr ago, which considerably slowed or terminated shelf sediment offloading.

scholarly journals Isolation and Identification of Sterols from a Pleistocene Sediment

Nature ◽  
1971 ◽  
Vol 231 (5301) ◽  
pp. 308-310 ◽  
Author(s):  
WILLIAM HENDERSON ◽  
WALTER E. REED ◽  
GORDON STEEL ◽  
MELVIN CALVIN
Keyword(s):  
Isolation And Identification ◽  
Pleistocene Sediment

scholarly journals ESR dose response of Al center measured in quartz samples from the Yellow River (China): Implications for the dating of Upper Pleistocene sediment

2013 ◽  
Vol 40 (4) ◽  
pp. 341-347 ◽  
Author(s):  
Pierre Voinchet ◽  
Gongming Yin ◽  
Christophe Falguères ◽  
Chunru Liu ◽  
Fei Han ◽  
...  
Keyword(s):  
Yellow River ◽  
Growth Curves ◽  
River System ◽  
The Yellow River ◽  
Esr Dating ◽  
Upper Pleistocene ◽  
Fluvial Terraces ◽  
Lower Pleistocene ◽  
Dating Method ◽  
Pleistocene Sediment

Abstract The ESR dating method requires to describe the evolution of the ESR signal intensities vs. increasing gamma doses, then to extrapolate the equivalent dose of radiation received by the sample since its deposition using mathematical fitting. The function classically used to describe the growth curves of ESR aluminium signal in quartz was recently discussed and challenged for Lower Pleistocene sediments. In the present work, some alluvial sediments sampled in Upper Pleistocene fluvial terraces of the Yellow River system (China) permit us to test the application of another extrapolation function (linear + exponential) recently proposed for Lower Pleistocene sediments. The equivalent doses obtained here for the recent deposits of the Yellow River system and the corresponding ages are promising and indicate the potential of ESR to date quartz deposits from Upper Pleistocene times.

Sign in / Sign up

Export Citation Format

Share Document