Vertical structure and dominating factors of sand body during Late Triassic Chang 9 time of Yanchang Formation in Ordos Basin, NW China
来源期刊：中南大学学报(英文版)2015年第4期
论文作者：DING Xiong CHEN Jing-shan TAN Xiu-cheng LIN Dan ZHAO Zi-hao YAO Jing-li DENG Xiu-qing LI Yuan-hao
文章页码：1405 - 1418
Key words：vertical structure; stacking pattern; sand body; Chang 9 time; Ordos Basin
Abstract: Based on a synthetic geological study of drilling, well logging and core observations, two main genetic types of Chang 9 sand body in Odors Basin were recognized, which included two effects, that is, delta environment and tractive current effects that lead to the development of mouth bar, distal bar, sheet sand and other sand bodies of subaerial and subaqueous distributary channel, natural levee, flood fan and delta front, and shore-shallow lake environment and lake flow transformation effects that result in the development of sandy beach bar, sheet sand and other sand bodies. Chang 9 sand body mainly developed five basic vertical structures, namely box shape, campaniform, infundibuliform, finger and dentoid. The vertical stacking patterns of multilayer sand body was complex, and the common shapes included box shape + box shape, campaniform + campaniform, campaniform + box shape, infundibuliform + infundibuliform, campaniform + infundibuliform, box shape + campaniform, box shape + infundibuliform, and finger + finger. Based on the analysis on major dominating factors of vertical structure of sand body, sedimentary environment, sedimentary facies and rise, fall and cycle of base level are identified as the major geological factors that control the vertical structure of single sand body as well as vertical stacking patterns and distribution of multistory sand bodies.
DING Xiong(丁熊)1, 2, 3, CHEN Jing-shan(陈景山)2, TAN Xiu-cheng(谭秀成)1, 2, LIN Dan(林丹)2, ZHAO Zi-hao(赵子豪)2, YAO Jing-li(姚泾利)4, DENG Xiu-qing(邓秀芹)4, LI Yuan-hao(李元昊)4
(1. State Key Laboratory of oil and Gas Reservoir Geology and exploitation
(China University of Southwest Petroleum), Chengdu 610500, China;
2. School of Geosciences and Technology, China University of Southwest Petroleum, Chengdu 610500, China;
3. Post-Doctor Station, China University of Chengdu Technology, Chengdu 610059, China;
4. Research Institute of Exploration and Development, PetroChina Changqing Oilfield Company, Xi’an 710021, China)
Abstract:Based on a synthetic geological study of drilling, well logging and core observations, two main genetic types of Chang 9 sand body in Odors Basin were recognized, which included two effects, that is, delta environment and tractive current effects that lead to the development of mouth bar, distal bar, sheet sand and other sand bodies of subaerial and subaqueous distributary channel, natural levee, flood fan and delta front, and shore-shallow lake environment and lake flow transformation effects that result in the development of sandy beach bar, sheet sand and other sand bodies. Chang 9 sand body mainly developed five basic vertical structures, namely box shape, campaniform, infundibuliform, finger and dentoid. The vertical stacking patterns of multilayer sand body was complex, and the common shapes included box shape + box shape, campaniform + campaniform, campaniform + box shape, infundibuliform + infundibuliform, campaniform + infundibuliform, box shape + campaniform, box shape + infundibuliform, and finger + finger. Based on the analysis on major dominating factors of vertical structure of sand body, sedimentary environment, sedimentary facies and rise, fall and cycle of base level are identified as the major geological factors that control the vertical structure of single sand body as well as vertical stacking patterns and distribution of multistory sand bodies.
Key words:vertical structure; stacking pattern; sand body; Chang 9 time; Ordos Basin
