There have been significant changes in sea level over the past two million years, and a complete understanding of natural cycles of change as well as anthropogenic effects is imperative for future ...global development. This book reviews the history of research into these sea-level changes and summarises the methods and analytical approaches used to interpret evidence for sea-level changes. It provides an overview of changing climates during the Quaternary, examines processes responsible for global variability of sea-level records, and presents detailed reviews of sea-level changes for the Pleistocene and Holocene. The book concludes by discussing current trends in sea levels and likely future sea-level changes. This is an important and authoritative resource for academic researchers and graduate and advanced undergraduate students working in tectonics, stratigraphy, geomorphology, physical geography, environmental science and other aspects of Quaternary studies.
The remains of porcupines from the Lower Pleistocene deposits of the Taurida karstic cave discovered in 2018 in central Crimea (Zuya village, Belogorsk district) are referred to Hystrix (Acanthion) ...vinogradovi Argyropulo, 1941. This species is quite common for the Pleistocene of Eurasia. In Crimea, several isolated teeth of this species were described from the Lower Pleistocene of Tarkhankut previously.
Marked by a progressive increase in the amplitude of climate oscillations, an evolving waveform, and a shift towards a quasi-100 ky frequency, the Early–Middle Pleistocene transition (EMPT), ...previously known as the Mid-Pleistocene Transition (or Mid-Pleistocene Revolution) (1.4–0.4 Ma), represents a fundamental transformation in the Earth's climate state. The EMPT began with a substantial change in climate dynamics and ended with the Mid-Brunhes Event, signaling the establishment of a new steady state. The reasons for the EMPT while uncertain appear to involve a non-linear response of the Earth climate system. The physical and biotic responses to this transition, amplified by the growth of Northern Hemisphere ice sheets, have been profound. Two important chronostratigraphic markers characterize the EMPT, the Jaramillo Subchron (1.070–0.988 Ma) and the Matuyama–Brunhes Chron boundary (∼773 ka). The latter has been chosen as the primary guide for the Lower–Middle Pleistocene Subseries boundary, as it lies at the approximate midpoint of the EMPT and aids in global recognition both in marine and terrestrial deposits. The Jaramillo Subchron has received less attention, but the late Early Pleistocene is important in Europe because it saw the progressive transition from the Villafranchian to Galerian mammal faunas, and expansion of hominins into western and northern Europe. The Jaramillo Subchron is represented by Marine Isotope Stages (MIS) 31 to 28, with MIS 30 already showing the asymmetrical (sawtooth) pattern characteristic of the Middle Pleistocene. Indeed, while variation in the 40-ky band (obliquity) remains strong throughout the EMPT, low frequency variability begins at around 1250–1200 ky, which coincides with a progressive increase in global ice volume. Against a backdrop of increasingly severe glacial cycles, notably during MIS 36, 34, 24–22 (the so-called “0.9 Ma event”), 16 and 12, pronounced phases of warming are also documented globally, including the “super-interglacial” MIS 31.
The early phase of the EMPT is characterized by important glaciations beginning with MIS 36 and continuing to MIS 24–22, a major intensification of the East Asian monsoon system, intensification of loess deposition in northern Europe, development of open landscapes in western Siberia, increased fluvial incision, higher amplitude sea-level change, and spread of large mammals across northern Eurasia, and a strong reduction in the North Atlantic thermohaline circulation. In Europe, the loss of thermophilous plant taxa during the EMPT and indeed throughout the Quaternary is a reminder of the progressive cooling that took place here and elsewhere.
The loess sequences in Tajikistan are an important archive of information about the development of climate and atmospheric circulation in central Asia during the Pleistocene. Here we present the ...results of an iron mineralogical study of a loess sequence in Tajikistan to reconstruct paleoclimate evolution during the mid‐Pleistocene and late Pleistocene. The record indicates that interglacial intervals were relatively humid and glacials were dry. We propose a shift in the character of the interglacial climate of the region to more humid after beginning of MIS 9; however, temperature was relatively stable. The location and intensity of Westerlies have a close link with Asian Summer Monsoon (ASM) circulations. From the beginning of MIS 9, there was a southward movement of the Westerlies circulation, which corresponded to a retreat of the Indian Summer Monsoon (ISM). A similar relationship also existed between the East Asian Summer Monsoon (EASM) circulation and the Westerlies, which is evidenced by the formation of the most weakly developed soil unit in the EASM‐dominated regions during MIS 9, in contrast with the formation of the most strongly developed soil unit in the Westerlies‐dominated regions. As conditions in the areas of loess deposition became more humid, the sedimentary basins which are the dust source areas became progressively more arid. The aridification of the source areas may be the result of increased Northern Hemisphere ice volume and accelerated high mountains and/or plateaus uplift in the surrounding regions.
Key Points
An iron mineralogical study of a loess sequence in Tajikistan to reconstruct paleoclimate evolution since mid‐Pleistocene
The location and intense of Westerlies in central Asia correspondingly changed with Asian Summer Monsoon circulation on orbital scale
The interglacial climate got humid in loess deposit area since MIS 9, but became progressively arid in its source area
We here reconstruct a glacial and climate history of arctic NW Siberia for the last ~600,000 years, based on the stratigraphy and chronology of 35 studied river sections on the southern Taimyr ...Peninsula. From this stratigraphic mosaic we have identified four glacial events, marked by tills/glaciotectonics, which are intercalated with mainly marine sediments deposited in proglacial settings during transitions from glacial conditions into subsequent interglacials/interstadials. The traces of early shelf-based Kara Sea Ice Sheet (KSIS) glaciations in marine isotope stages (MIS) 12–14 and 8 are sparsely preserved, but these ice advances are suggested to have terminated far south into the central Siberian uplands, as also was the case with the younger Taz glaciation (MIS 6). The inception phase of the latter glaciation was complex, with ice advancing into a proglacial marine basin both from the south (Putorana – Anabar uplands) and the north. The deglaciation leading into the Karginsky interglacial (MIS 5e) was marked by the development of the southernmost ice-marginal zones (IMZs) on the Taimyr lowlands – the Urdakh and Sampesa IMZs. The most recent (late Pleistocene) glacial cycle is recorded by three successively smaller KSIS advances from the Kara Sea shelf onto Taimyr, of which only the first, during Early Zyryanka (MIS 5d), reached south of the Byrranga Mountains, with its maximum extent marked by the Jangoda – Syntabul – Severokokorsky IMZ. Retreat of the ice margin during MIS 5c-b was accompanied by deposition of glaciomarine sediment in the proglacial basin and deposition of large successions of delta sediments in the foothills of the Byrranga Mountains, reaching ≥100 m above present sea level. The region north of the Byrranga Mountains was subjected to two subsequent KSIS glaciations, during MIS 4 and MIS 2, while the area south of the Byrranga Mountains transitioned to a terrestrial environment from the Middle into the Lower Zyryanka, as evidenced by deposition of fluvial, aeolian and ice-complex (Yedoma) sediments.
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