S N Rajaguru
Articles written in Journal of Earth System Science
Volume 89 Issue 1 March 1980 pp 51-66
Quaternary formations in western Rajasthan are of fluvial, locustrinal and aeolian origins. Fossil gravel ridge of Jayal in Nagaur District is one of the earliest quaternary formations so far recorded in the region. A rich lower palaeolithic habitation-cum-workshop site has been discovered in association with the gravel ridge. Multiple evidence for climatic change in the area during the quaternary period is discussed.
Volume 113 Issue 3 September 2004 pp 403-425
Two playas in the arid core of the western margin of the Thar desert viz., Bap-Malar and Kanod, have been investigated using palynology, geomorphology, archaeology, AMS-radiocarbon dating, stable isotopes, evaporite mineralogy and geoarchaeology. The principal objective was to obtain a reliable lithostratigraphy of the playa sediments. These are about 7 m thick in the Bap-Malar and > 2.5 to 3 m thick in the Kanod. AMS14C dates of > 15 ka BP on pollen from sediment layers indicates that the Bap-Malar playa possibly existed even during the LGM. These playas were full of water during the early Holocene (8 ka BP — 5.5 ka BP) and were ephemeral during the Pleistocene-Holocene transition and early to mid to late Holocene. The playas dried almost 1000 years earlier than those occurring on the eastern margin. Pollen of graminaceae, chenopodiaceae/amaranthaceae, cyperaceae etc. and evaporite minerals like gypsum, halite in the profiles indicate that the playas were surrounded by vegetation dominated by grass and that, they remained brackish to saline even during the mid Holocene, lake full stage. Stable dune surfaces, pediments with regoliths, and gravelly channels of ephemeral streams provided a favorable geomorphic niche for nomadic human activity since ∼ 7 ka BP. Though local ecological factors have played an important role in the evolution of the playas, the winter rains, connected with northwesterly depressions, most likely played a vital role in maintaining these playas
Volume 128 | Issue 8
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