Cosmogenic exposure dating

Terrestrial cosmogenic nuclide surface exposure dating of moraine boulders and alluvial fan sediments define the timing of five glacial advances over at least the last five glacial cycles in the Ladakh Range of the Transhimalaya.The glacial stages that have been identified are: the Indus Valley glacial stage, dated at older than 430 ka; the Leh glacial stage occurring in the penultimate glacial cycle or older; the Karglacial stage, occurring during the early part of the last glacial cycle; the Bazgo glacial stage, at its maximum during the middle of the last glacial cycle; and the early Holocene Khalling glacial stage.A possible explanation is that uplift of Himalayan ranges to the south and/or of the Karakoram Mountains to the west of the region may have effectively blocked moisture supply by the south Asian summer monsoon and mid-latitude westerlies, respectively. Alternatively, this pattern of glaciation may reflect a trend of progressively less extensive glaciation in mountain regions that has been observed globally throughout the Pleistocene. By using our site, you agree to our collection of information through the use of cookies. Google(); req('single_work'); $('.js-splash-single-step-signup-download-button').one('click', function(e){ req_and_ready('single_work', function() ); new c. It is effective on timescales of several millions of years.It assumes that boulders have not been buried and then re-exposed at the Earth’s surface.

Be production rate is carefully calibrated, for example by correcting for partial attenuation and complete shielding effects.Contact us if you experience any difficulty logging in.uses cookies to personalize content, tailor ads and improve the user experience. Unconsolidated sediments contain magnetic minerals, such as those on the continental shelf and slope. The remnant magnetism of the sediment is a reflection of the earth’s palaeomagnetic field at the time of deposition.The sediments can be compared to palaeo magnetostratigraphic data, and this can be used as a proxy age determination.

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