Changes in the volume and salinity of Lake Khubsugul (Mongolia) in response to global climate changes in the upper Pleistocene and the Holocene
Fedotov, A. P.; Chebykin, E.P.; Yu Semenov, M.; Vorobyova, S.S. ; Yu Osipov, E.; Golobokova, L.P.; Pogodaeva, T.V.; Zheleznyakova, T.O.; Grachev, M.A.; Tomurhuu, D.; Oyunchimeg, Ts.; Narantsetseg, Ts.; Tomurtogoo, O.; Dolgikh, P.T.; Arsenyuk, M.I.; De Batist, M. (2004). Changes in the volume and salinity of Lake Khubsugul (Mongolia) in response to global climate changes in the upper Pleistocene and the Holocene. Palaeogeogr. Palaeoclimatol. Palaeoecol. 209(1-4): 245-257. dx.doi.org/10.1016/j.palaeo.2003.12.022
In: Palaeogeography, Palaeoclimatology, Palaeoecology. Elsevier: Amsterdam; Tokyo; Oxford; New York. ISSN 0031-0182; e-ISSN 1872-616X, meer
|  |
| Author keywords |
Paleoclimate; Lake Khubsugul level change; LGM; Holocene; Mongolia |
| Auteurs | | Top |
- Fedotov, A. P.
- Chebykin, E.P.
- Yu Semenov, M.
- Vorobyova, S.S.
- Yu Osipov, E.
- Golobokova, L.P.
|
- Pogodaeva, T.V.
- Zheleznyakova, T.O.
- Grachev, M.A.
- Tomurhuu, D.
- Oyunchimeg, Ts.
|
- Narantsetseg, Ts.
- Tomurtogoo, O.
- Dolgikh, P.T.
- Arsenyuk, M.I.
- De Batist, M., meer
|
| Abstract |
Two gravity cores (1.1 and 2.2 m long) of deep-water bottom sediments from Lake Khubsugul (Mongolia) were studied. The Holocene, biogenic silica and organic matter-rich part of the first core was subjected to AMS radiocarbon dating which placed the date of dramatic increase of pelagic diatoms (40 cm below sediment surface) at a calendar age of 11.5 cal ky BP. ICP-MS analysis of weak nitric acid extracts revealed that the upper Pleistocene, compared to the Holocene samples, were enriched in Ca, Cinorg, Sr, Mg and depleted of U, W, Sb, V and some other elements. Transition to the Holocene resulted in an increase of total diatoms from 0 to 108 g-1, of BiSi from 1% to 20%, of organic matter from <1% to >6%. The Bølling–Allerød–Younger Dryas–Holocene abrupt climate oscillations manifested themselves in oscillations of geochemical proxies. A remarkable oscillation also occurred at 22 cm (ca. 5.5 ky BP). The Pleistocene section of the second, longer core was enriched in carbonate CO2 (up to 10%) and water-extractable SO42- (up to 300 times greater than that in Holocene pore waters). All this evidence is in an accord with the earlier finding of drowned paleo-deltas at ca. 170 m below the modern lake surface of the lake [Dokl. Akad. Nauk 382 (2002) 261] and suggests that, due to low (ca. 110 mm) regional precipitation at the end of the Pleistocene, Lake Khubsugul was only 100 m deep, and that its volume was ca. 10 times less than today. |
|
