ABSTRACT Lake Coyote, California, which formed in one of five basins along the Mojave River, acted both as a part of the Lake Manix basin and, after the formation of Afton Canyon and draining of Lake Manix ca. 24.5 calibrated (cal) ka, a side basin that was filled episodically for the next 10,000 yr. As such, its record of lake level is an important counterpart to the record of the other terminal basin, Lake Mojave, following the draining of Lake Manix. We studied lake and fluvial deposits and their geomorphology and identified five principal periods of recurring lakes in the Coyote basin by dating mollusks. Several of these periods in detail consist of multiple lake-rise pulses, for which we identified specific fluvial deposits that represent the Mojave River entering the basin. The pulsed record of rapid lake rise and decline is interpreted as switching of the Mojave River between Lake Coyote and Lake Mojave. A composite lake record for both basins shows nearly continuous lake maintenance by the Mojave River from 24.5 cal ka to ca. 14 cal ka. One potential gap in the lake record, ca. 22.7–21.8 cal ka, may indicate either temporary river routing to yet another basin or a dry climatic period. The Mojave River discharge was sufficient to maintain at least one terminal lake throughout most of the Last Glacial Maximum and deglacial periods, indicating that paleoclimate was moist and/or cool well into the Bølling-Allerød and that the lake records may not be sensitive to variations from moderate to high discharge. Nuances of lake-level changes in both the Coyote and Mojave basins are difficult to interpret as paleoclimatic events because the current chronologic control on lake levels from nearshore deposits does not provide the necessary precision. Mojave River avulsion leading to flow to Coyote basin may have been influenced by rupture on a dextral-oblique fault. Earliest post–Lake Manix stream deposits of the Mojave River leading to the Coyote basin are faulted, and most subsequent streams were confined to the downthrown fault block. This fault rupture and possible enhanced river routes to Lake Coyote, rather than Lake Mojave, are bracketed by dated beach deposits to the period ca. 20–19 cal ka. Later, headward erosion through the fluvial plain by the Mojave River eliminated flow to Coyote basin after ca. 14 cal ka and completed incision of the plain after ca. 12 cal ka.

Abstract The Norwegian coast facing the Atlantic Ocean was ice free as early as the Allerød oscillation in the late Pleistocene. The landscape was probably habitable for humans. It has, therefore, been assumed by several scholars that this coastline was visited or inhabited from the Late Glacial period onwards. In part, this argumentation is based on the presumed proximity of the Norwegian mainland and Doggerland, which existed between present-day Denmark and Great Britain because of a much lower global sea level. The aim of this paper is to examine the 14 C dates available from the oldest Norwegian settlement sites, and to compare them to the Quaternary processes of deglaciation and sea-level change. The hypothesis is advanced that humans did not settle in present-day Norway before a sheltering passage of islands and peninsulas had developed between the Swedish west coast (Bohuslän) and the Oslo area. This happened in the second half of the Preboreal period, at approximately 9.3 cal ka BC, or in the final centuries of the tenth millenniun BC. Supplementary material: 14 C dates used in Figures 2, 4 and 9 are available at http://www.geolsoc.org.uk/SUP18779 .

Abstract As the late Pleistocene Cordilleran Ice Sheet (CIS) retreated from the southern Puget Lowland and thinned rapidly, marine waters invaded the central and northern lowland, floating the residual ice and causing wholesale collapse of the CIS from southern Whidbey Island to southern British Columbia. Massive, poorly sorted Everson glaciomarine drift was deposited contemporaneously over the entire central and northern lowland. More than 160 14 C dates show that the Everson interval began 12,500 14 C yr B.P. and ended 11,700 14 C yr B.P. Numerous marine strandlines record the drop in relative sea level in the Fraser Lowland from ~180 m (600 ft) at the end of the Everson interval to near present sea level. Following emergence of the Fraser Lowland, a lobe of the CIS advanced from the Fraser Canyon near Sumas to Bellingham during the Sumas Stade. As the ice retreated, at least eight end moraines were built successively across the lowland, each marking a position of ice advance or stillstand that records late Pleistocene climatic fluctuations. About 40 new 14 C dates indicate that the ages of these moraines span the Inter-Allerød–Younger Dryas intervals between 11,700 and 10,000 14 C yr B.P. The 14 C chronology allows correlation of the Sumas moraines with moraines in the Cascade Range, Rocky Mountains, Canada, Scandinavia, the European Alps, New Zealand, South America, and elsewhere. Late in the retreat of the ice, large outburst floods from an ice-dammed lake in British Columbia swept across the Sumas outwash plain, resulting in fluted topography and giant ripples on dune forms.

This paper describes the relationship between sea levels and climate based on the links between sea-level variations and river runoff. During the final late Pleistocene and postglacial periods, the Caspian Sea fluctuated between regression and transgression stages. The Black Sea experienced fluctuations as well, but these were mainly controlled by the world ocean due to water exchange through the Bosporus Strait. Sometimes, the Caspian Sea overflowed into the Black Sea through the Manych Strait, and they periodically coalesced. Change in the level of both seas could be interpreted as responses to the regional-scale water budget (the balance between inflow and outflow components). These components can be calculated from atmospheric general circulation models. This approach uses climate modeling data to reproduce river runoff changes, and, consequently, variations in seawater and sea level under contrasting climate conditions. In response to glacial conditions of the last cold Pleistocene event, the lowering levels of the Black Sea (post-Karangatian regression stage) and the Caspian Sea (Atelian regression stage) are simulated simultaneously. This lends credence to the idea of the connection between deep regression states of the Caspian and Black Seas and mature stages of the late Quaternary glacial/cooling/drying planetary events. Analysis of observed information allows us to conclude—taking into account the uncertainties of reconstructed data—that at least two regression stages occurred simultaneously with late Quaternary glacial planetary events. The simulation of transgression stages (their onset and duration) remains a very difficult problem. Results of modeling have shown that during the warm periods (taking as examples the mid-Holocene and Allerød events), simulated river runoff did not increase to the extent needed for a strong transgression and overflow of the Caspian Sea into the Black Sea through the Manych Strait. Thus, there is no clear understanding about the source of “additional” water volume necessary to elevate the level of the Caspian Sea to a point that would permit overflow into the Black Sea.

We discuss pollen, soil, geomorphologic, and archaeological records used for reconstructing climatic, biogeographic, and human-environment events in the Crimean Peninsula during the past 130 k.y. Warm and moist conditions conducive to forest growth prevailed during the Eemian Interglacial (marine isotope stage [MIS] 5e). Although sea levels were higher than at present, a review of the stratigraphic and geomorphic data suggests that the peninsula was not detached from the mainland. During the last glacial period (MIS 5d–MIS 2), conditions fluctuated between steppe and tree growth in warmer places during the stadials, and forest-steppe during the interstadials. The Pleistocene–Holocene transition involved forest growth during the Bølling-Allerød interstadials, steppe during the Younger Dryas, and a forest-steppe during the early Holocene. The establishment of the modern Black Sea ca. 7 ka and increasing temperatures led to the formation of the modern vegetation belts, ushering in optimal conditions for the establishment of Neolithic communities. A dry period peaked around 4–3.5 ka, followed by milder conditions that lasted until the colonization of Crimea by Greek farmers during the middle part of the first millennium A.D. Dry conditions at the end of the same millennium led to the abandonment of agriculture and settlement decline. Sea-level oscillations during the late Holocene had an important effect on shoreline configuration, lagoonal systems, coastal wetlands, and human settlements. Data used in this paper were drawn from a number of published papers, mostly in Russian and Ukrainian, as well as records produced by the authors' research.