Depositional environments and tectonic controls on the coal-bearing Lower to Middle Jurassic Yan'an Formation, southern Ordos Basin, China

Research Article| December 01, 1989 Depositional environments and tectonic controls on the coal-bearing Lower to Middle Jurassic Yan'an Formation, southern Ordos Basin, China Edward A. Johnson; Edward A. Johnson 1U.S. Geological Survey, Box 25046, Federal Center, M.S. 939 Denver, Colorado 80225 Search for other works by this author on: GSW Google Scholar Shu Liu; Shu Liu 2Geological Bureau of the Ministry of Coal Industry People's Republic of China Search for other works by this author on: GSW Google Scholar Yonglin Zhang Yonglin Zhang 2Geological Bureau of the Ministry of Coal Industry People's Republic of China Search for other works by this author on: GSW Google Scholar Author and Article Information Edward A. Johnson 1U.S. Geological Survey, Box 25046, Federal Center, M.S. 939 Denver, Colorado 80225 Shu Liu 2Geological Bureau of the Ministry of Coal Industry People's Republic of China Yonglin Zhang 2Geological Bureau of the Ministry of Coal Industry People's Republic of China Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1989) 17 (12): 1123–1126. https://doi.org/10.1130/0091-7613(1989)017<1123:DEATCO>2.3.CO;2 Article history First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Edward A. Johnson, Shu Liu, Yonglin Zhang; Depositional environments and tectonic controls on the coal-bearing Lower to Middle Jurassic Yan'an Formation, southern Ordos Basin, China. Geology 1989;; 17 (12): 1123–1126. doi: https://doi.org/10.1130/0091-7613(1989)017<1123:DEATCO>2.3.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 SocietyGeology Search Advanced Search Abstract The Ordos Basin of north-central China is well known for vast energy resources. This nonmarine interior basin developed on the North China-Korean platform following the Late Triassic Indochina orogeny and, for a time, contained a large freshwater lake prior to being uplifted into its present form at the close of the Mesozoic. Lower to Middle Jurassic coal occurs in the fluviolacustrine Yan'an Formation along the southern margin of the basin in the Huanglong coalfield. In the northeast part of the field, the formation ranges from 0 to 180 m in thickness and is divided into five fining-upward members, each representing a regressive-transgressive lacustrine cycle. Low-sulfur, high-volatile bituminous coal is complexly distributed in the lowest member of the Yan'an Formation. Deposition of this member was influenced by two tectonic events that controlled coal occurrence. First, regional uplifts were produced by the Late Triassic Indochina orogeny and left as highlands on the pre-Yan'an, Triassic land surface; in the lowest member, coal beds thin toward and pinch out against these highlands. Second, syndepositional tectonism of the Jurassic through Cretaceous Yanshan orogeny created a series of northeast-trending folds that were topographically expressed as evolving highs and lows. Swamps and resulting peat accumulation preferentially occupied the subsiding paleodepressions. Because of the tectonic influence on peat accumulation, coal beds thin and merge toward anticlines and thicken and split toward synclines. In addition, coal quality is documented to be less variable along a northeast trend than along a northwest trend. 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.