TY - JOUR A1 - Dosseto, Anthony A1 - May, Jan-Hendrik A1 - Choi, Jeong-Heon A1 - Swander, Zachary J. A1 - Fink, David A1 - Korup, Oliver A1 - Hesse, Paul A1 - Singh, Tejpal A1 - Mifsud, Charles A1 - Srivastava, Pradeep T1 - Late quaternary fluvial incision and aggradation in the Lesser Himalaya, India JF - Quaternary science reviews : the international multidisciplinary research and review journal N2 - Reconstructing how rivers respond to changes in runoff or sediment supply by incising or aggrading has been pivotal in gauging the role of the Indian Summer Monsoon (ISM) as a geomorphic driver in the Himalayas. Here we present new chronological data for fluvial aggradation and incision from the Donga alluvial fan and the upper Alaknanda River, as well as a compilation of previous work. In addition to conventional OSL-SAR (Single-Aliquot Regenerative-Dose) dating method, we have tested and applied pulsed OSL (POSL) dating for quartz samples that include K-rich feldspar inclusions, which is expected to improve the applicability and validity of OSL ages in the Lesser Himalaya. For previously dated deposits, our OSL ages are shown to be systematically older than previously reported ages. These results suggest periods of aggradation in the Alaknanda and Dehradun Valleys mainly between similar to 25 and 35 ka. This most likely reflects decreased stream power during periods of weakened monsoon. In addition, in-situ cosmogenic beryllium-10 was used to infer bedrock surface exposure ages, which are interpreted as episodes of active fluvial erosion. Resulting exposure ages span from 3 to 6 ka, suggesting that strath terraces were exposed relatively recently, and incision was dominant through most of the Holocene. In combination, our results support precipitation-driven fluvial dynamics, which regulates the balance between stream power and sediment supply. On a larger spatial scale, however, fluvial dynamics are probably not spatially homogeneous as aggradation could have been taking place in adjacent catchments while incision dominated in the study area. (C) 2018 Elsevier Ltd. All rights reserved. Y1 - 2018 U6 - https://doi.org/10.1016/j.quascirev.2018.07.035 SN - 0277-3791 VL - 197 SP - 112 EP - 128 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Margold, Martin A1 - Jansen, John D. A1 - Gurinov, Artem L. A1 - Codilean, Alexandru T. A1 - Fink, David A1 - Preusser, Frank A1 - Reznichenko, Natalya V. A1 - Mifsud, Charles T1 - Extensive glaciation in Transbaikalia, Siberia, at the Last Glacial Maximum JF - Quaternary science reviews : the international multidisciplinary research and review journal N2 - Successively smaller glacial extents have been proposed for continental Eurasia during the stadials of the last glacial period leading up to the Last Glacial Maximum (LGM). At the same time the large mountainous region east of Lake Baikal, Transbaikalia, has remained unexplored in terms of glacial chronology despite clear geomorphological evidence of substantial past glaciations. We have applied cosmogenic Be-10 exposure dating and optically stimulated luminescence to establish the first quantitative glacial chronology for this region. Based on eighteen exposure ages from five moraine complexes, we propose that large mountain ice fields existed in the Kodar and Udokan mountains during Oxygen Isotope Stage 2, commensurate with the global LGM. These ice fields fed valley glaciers (>100 km in length) reaching down to the Chara Depression between the Kodar and Udokan mountains and to the valley of the Vitim River northwest of the Kodar Mountains. Two of the investigated moraines date to the Late Glacial, but indications of incomplete exposure among some of the sampled boulders obscure the specific details of the post-LGM glacial history. In addition to the LGM ice fields in the highest mountains of Transbaikalia, we report geomorphological evidence of a much more extensive, ice-cap type glaciation at a time that is yet to be firmly resolved. (C) 2015 Elsevier Ltd. All rights reserved. KW - Glaciation KW - Transbaikalia KW - Last Glacial Maximum KW - Cosmogenic Be-10 exposure dating KW - Optically stimulated luminescence Y1 - 2016 U6 - https://doi.org/10.1016/j.quascirev.2015.11.018 SN - 0277-3791 VL - 132 SP - 161 EP - 174 PB - Elsevier CY - Oxford ER -