Quaternary Glacial Record in Swat Kohistan, West Pakistan

Abstract

Research Article| May 01, 1970 Quaternary Glacial Record in Swat Kohistan, West Pakistan STEPHEN C PORTER STEPHEN C PORTER Department of Geological Sciences, University of Washington, Seattle, Washington 98105 Search for other works by this author on: GSW Google Scholar Author and Article Information STEPHEN C PORTER Department of Geological Sciences, University of Washington, Seattle, Washington 98105 Publisher: Geological Society of America Received: 07 Aug 1969 Revision Received: 16 Dec 1969 First Online: 02 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Copyright © 1970, The Geological Society of America, Inc. Copyright is not claimed on any material prepared by U.S. government employees within the scope of their employment. GSA Bulletin (1970) 81 (5): 1421–1446. https://doi.org/10.1130/0016-7606(1970)81[1421:QGRISK]2.0.CO;2 Article history Received: 07 Aug 1969 Revision Received: 16 Dec 1969 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation STEPHEN C PORTER; Quaternary Glacial Record in Swat Kohistan, West Pakistan. GSA Bulletin 1970;; 81 (5): 1421–1446. doi: https://doi.org/10.1130/0016-7606(1970)81[1421:QGRISK]2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract During three Pleistocene glaciations, large valley glaciers originating at altitudes of 12,000 ft or more occupied the northern part of the Swat River drainage basin and terminated at altitudes as low as 5800 ft. Discrimination and subdivision of the three principal drift sheets is based on various relative-age criteria, including moraine and terrace morphology, weathering characteristics of surface stones, and degree of soil development. The areal and altitudinal distribution of the three drifts, which are designated Laikot (oldest), Gabral, and Kalam, indicates a less extensive glacier cover during each successive glacial age (510 mi2, 473 mi2, and 430 mi2, respectively). Laikot Drift is poorly preserved, strongly weathered, and retains little or no depositional morphology. Moraines and outwash terraces built during the Gabral and Kalam advances are well preserved in two intermont valleys at Kalam and Utrot and permit subdivision of the two younger drifts into two and three units, respectively, of lesser stratigraphic rank. Moraines of Gabral age tend to be broad and smooth and have few surface stones, whereas those of Kalam age are bouldery and sharp-crested.The altitude of the equilibrium-line (ELA) for existing glaciers in Swat Kohistan ranges from 13,000 to 14,000 ft. Assuming accumulation-area ratios of 0.6 ± 0.1 for Pleistocene glaciers in this region, steady-state ELA's during former glaciations are estimated to have been some 3000 to 3600 ft below their present levels. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.