Lower- to Middle Pleistocene flank margin caves at Custonaci (Trapani, NW Sicily) and their relation with past sea levels

Abstract. Sediment core ARC4-BN05 collected from the Canada Basin, Arctic Ocean, covers the late to middle Quaternary (Marine Isotope Stage – MIS – 1–15, ca. 0.5–0.6 Ma) as estimated by correlation to earlier proposed Arctic Ocean stratigraphies and AMS14C dating of the youngest sediments. Detailed examination of clay and bulk mineralogy along with grain size, content of Ca and Mn, and planktic foraminiferal numbers in core ARC4–BN05 provides important new information about sedimentary environments and provenance. We use increased contents of coarse debris as an indicator of glacier collapse events at the margins of the western Arctic Ocean, and identify the provenance of these events from mineralogical composition. Notably, peaks of dolomite debris, including large dropstones, track the Laurentide Ice Sheet (LIS) discharge events to the Arctic Ocean. Major LIS inputs occurred during the stratigraphic intervals estimated as MIS 3, intra-MIS 5 and 7 events, MIS 8, and MIS 10. Inputs from the East Siberian Ice Sheet (ESIS) are inferred from peaks of smectite, kaolinite, and chlorite associated with coarse sediment. Major ESIS sedimentary events occurred in the intervals estimated as MIS 4, MIS 6 and MIS 12. Differences in LIS vs. ESIS inputs can be explained by ice-sheet configurations at different sea levels, sediment delivery mechanisms (iceberg rafting, suspension plumes, and debris flows), and surface circulation. A long-term change in the pattern of sediment inputs, with an apparent step change near the estimated MIS 7–8 boundary (ca. 0.25 Ma), presumably indicates an overall glacial expansion at the western Arctic margins, especially in North America.

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Biostratigraphic Correlation of Pleistocene Marine Deposits and Sea Levels, Atlantic Coastal Plain of the Southeastern United States

Quaternary Research ◽

10.1016/0033-5894(80)90030-7 ◽

1980 ◽

Vol 13 (2) ◽

pp. 213-229 ◽

Cited By ~ 17

Author(s):

Thomas M. Cronin

Keyword(s):

North Carolina ◽

South Carolina ◽

Sea Level ◽

Late Pleistocene ◽

Coastal Plain ◽

Atlantic Coastal Plain ◽

Early Pleistocene ◽

Middle Pleistocene ◽

Sea Levels ◽

Atlantic Coastal

AbstractMarine ostracodes from 50 localities were studied to determine the age and elevation of Pleistocene sea levels in the Atlantic coastal plain from Maryland to northern Florida. Using ostracode taxon and concurrent ranges, published planktic biostratigraphic, paleomagnetic, and radiometric data, ostracode assemblage zones representing early (1.8-1.0 my), middle (0.7-0.4 my), and late (0.3-0.01 my) Pleistocene deposition were recognized and used as a basis for correlation. Ostracode biofacies signifying lagoonal, oyster bank, estuarine, open sound, and inner sublittoral environments provided estimated ranges of paleodepths for each locality. From these data the following minimum and maximum Pleistocene sea-level estimates were determined for the southeastern coastal plain: late Pleistocene, 2–10 m from Maryland to northern Florida; middle Pleistocene, 6–15 m in northern South Carolina; early Pleistocene, 4–22 m in central North Carolina, 13–35 m in southern North Carolina, and 6–27 m in South Carolina. Climatically induced glacio-eustatic sea-level fluctuations adequately account for the late Pleistocene sea-level data, but other factors, possibly differential crustal uplift, may have complicated the early Pleistocene record.

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Cenozoic geologic evolution of the lower Colorado River Basin, Northern Patagonia, Argentina

Andean geology ◽

10.5027/andgeov46n1-3060 ◽

2018 ◽

Vol 46 (1) ◽

pp. 131 ◽

Cited By ~ 4

Author(s):

Carina Seitz ◽

María I. Vélez ◽

Gerardo M.E. Perillo

Keyword(s):

Sea Level ◽

Shallow Lakes ◽

Colorado River ◽

Alluvial Fan ◽

Middle Pleistocene ◽

Humid Climate ◽

Sea Levels ◽

Middle Holocene ◽

Northern Patagonia ◽

Dry Conditions

Climatic changes and eustatic sea levels have been assumed to be the most important controllers of the Colorado River alluvial fan in northern Patagonia. Although the alluvial fan occurs in a region considered tectonically stable, there are pieces of evidence that the Miocene Andean orogeny has reactivated inherited structures, with subsequent geomorphological changes that date back to the Pleistocene. Besides, the clear evidence of neotectonism in the region and their effects on the evolution of this fan, it has not been studied in detail yet. In this study, we map and analyze six sections outcropping in different terraces of the alluvial fan with the primary aim of disentangling the role of tectonism, climate and eustatic changes on the evolution of the alluvial fan. This study is part of a bigger project aimed to understand the origin of the shallow lakes occurring in northern Patagonia. Our results indicate that the alluvial fan of the Colorado River was established in the area around the Middle Pleistocene. Evidence of deformations in Miocene to Pleistocene units indicates significant neotectonism during the Upper Pleistocene. By the Pleistocene-Holocene transition, tectonism produced incision generating a set of terraces. After this time, an important climate change from semiarid to arid favored the calcretization of some terraces. By the Pleistocene-Middle Holocene, the terraces were covered by ancient eolian sediment accumulated during dry conditions. By the Middle Holocene, a broad alluvial fan developed in the region under a warmer and more humid climate generating the Alluvial Colorado River-III deposit at the T3 terrace. In the late Holocene, aggradation process was favored by a high sea level and temperate-arid climate, producing T4 terrace. At the same time, this climate condition favored the local deflation-sedimentation processes that resulted in the deposition of modern eolian deposits (mE) over the T3 terrace. The depressions generated by the deflation were, later on, occupied by shallow lakes when the climate turn more humid. Subsequently, during regressive sea level condition, ca. 2000 years BP, the T4 terrace was partially eroded and the modern alluvial plain formed.

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Ancient divergence time estimates inEutropis rugiferasupport the existence of Pleistocene barriers on the exposed Sunda Shelf

PeerJ ◽

10.7717/peerj.3762 ◽

2017 ◽

Vol 5 ◽

pp. e3762 ◽

Cited By ~ 1

Author(s):

Benjamin R. Karin ◽

Indraneil Das ◽

Todd R. Jackman ◽

Aaron M. Bauer

Keyword(s):

Sea Level ◽

Divergence Time ◽

Peninsular Malaysia ◽

Middle Pleistocene ◽

Divergence Times ◽

Sea Level Changes ◽

Sunda Shelf ◽

Sea Levels ◽

Island Populations ◽

Divergence Time Estimates

Episodic sea level changes that repeatedly exposed and inundated the Sunda Shelf characterize the Pleistocene. Available evidence points to a more xeric central Sunda Shelf during periods of low sea levels, and despite the broad land connections that persisted during this time, some organisms are assumed to have faced barriers to dispersal between land-masses on the Sunda Shelf.Eutropis rugiferais a secretive, forest adapted scincid lizard that ranges across the Sunda Shelf. In this study, we sequenced one mitochondrial (ND2) and four nuclear (BRCA1,BRCA2,RAG1, andMC1R) markers and generated a time-calibrated phylogeny in BEAST to test whether divergence times between Sundaic populations ofE. rugiferaoccurred during Pleistocene sea-level changes, or if they predate the Pleistocene. We find thatE. rugiferashows pre-Pleistocene divergences between populations on different Sundaic land-masses. The earliest divergence withinE. rugiferaseparates the Philippine samples from the Sundaic samples approximately 16 Ma; the Philippine populations thus cannot be considered conspecific with Sundaic congeners. Sundaic populations diverged approximately 6 Ma, and populations within Borneo from Sabah and Sarawak separated approximately 4.5 Ma in the early Pliocene, followed by further cladogenesis in Sarawak through the Pleistocene. Divergence of peninsular Malaysian populations from the Mentawai Archipelago occurred approximately 5 Ma. Separation among island populations from the Mentawai Archipelago likely dates to the Pliocene/Pleistocene boundary approximately 3.5 Ma, and our samples from peninsular Malaysia appear to coalesce in the middle Pleistocene, about 1 Ma. Coupled with the monophyly of these populations, these divergence times suggest that despite consistent land-connections between these regions throughout the PleistoceneE. rugiferastill faced barriers to dispersal, which may be a result of environmental shifts that accompanied the sea-level changes.

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Holocene relative sea levels and coastal changes in the lower Cree valley and estuary, SW Scotland, U.K.

Transactions of the Royal Society of Edinburgh Earth Sciences ◽

10.1017/s0263593302000172 ◽

2002 ◽

Vol 93 (04) ◽

pp. 301 ◽

Cited By ~ 1

Keyword(s):

Sea Levels ◽

Coastal Changes

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Review for "A decrease in temperature during the late Middle Pleistocene interglacial stage (MIS 7.3) altered montane zone floral diversity: Plant macrofossil evidence from central Japan"

10.1002/gj.3833/v2/review1 ◽

2020 ◽

Keyword(s):

Middle Pleistocene ◽

Central Japan ◽

Plant Macrofossil ◽

Floral Diversity ◽

Montane Zone ◽

Late Middle Pleistocene

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Climate Change and Land Use Change of Rural Households in The Red River Delta, Vietnam

Journal of Economics and Development ◽

10.33301/2013.15.02.05 ◽

2013 ◽

pp. 79-94

Author(s):

Ngoc Luu Bich

Keyword(s):

Climate Change ◽

Land Use ◽

Agricultural Land ◽

Rural Households ◽

River Delta ◽

Red River ◽

Red River Delta ◽

Sea Levels ◽

Main Production ◽

Farming Households

Climate change (CC) and its impacts on the socio-economy and the development of communities has become an issue causing very special concern. The rise in global temperatures, in sea levels, extreme weather phenomena, and salinization have occurred more and more and have directly influenced the livelihoods of rural households in the Red River Delta – one of the two regions projected to suffer strongly from climate change in Vietnam. For farming households in this region, the major and traditional livelihoods are based on main production materials as agricultural land, or aquacultural water surface Changes in the land use of rural households in the Red River Delta during recent times was influenced strongly by the Renovation policy in agriculture as well as the process of industrialization and modernization in the country. Climate change over the past 5 years (2005-2011) has started influencing household land use with the concrete manifestations being the reduction of the area cultivated and the changing of the purpose of land use.

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