|
|
| |
|
|
| 本文已被：浏览次 下载次 |
码上扫一扫！ |
|
|
| 川南地区龙马溪组沉积亚相精细划分及地质意义 |
|
蒲泊伶1,2,董大忠3,4,5,王凤琴1,2,刘桂珍1,2,王玉满3,黄金亮3
|
|
(1.西安石油大学地球科学与工程学院,陕西西安 710065;2.西安石油大学陕西省油气成藏地质学重点实验室, 陕西西安 710065;3.中国石油勘探开发研究院,北京 100083;4.国家能源页岩气研发(实验)中心,河北廊坊 065007;5.中国石油天然气集团有限公司非常规油气重点实验室,河北廊坊 065007)
|
|
| 摘要: |
| 为查明川南地区下志留统龙马溪组富有机质页岩的沉积演化特征,通过岩性、岩相、沉积构造、有机质含量、矿物组成、生物化石和测井响应等特征,对龙马溪组页岩的岩相及沉积亚相类型进行精细划分,并建立四川盆地南部龙马溪组页岩沉积演化模式。结果表明:研究区龙马溪组页岩发育笔石页岩相、碳质页岩相、硅质页岩相、钙质页岩相、泥质灰岩相、粉砂质页岩相、黏土岩相7种岩石相类型;沉积亚相类型可划分为深水陆棚亚相、半深水陆棚亚相及浅水陆棚亚相3种类型;从笔石的生存环境来看,不同地质时代沉积水深存在差异;龙马溪组沉积时期从鲁丹阶到特列奇阶,沉积中心从长宁地区逐渐向北西方向迁移到威远地区,威远地区经历了3期沉积,长宁地区经历了2期沉积;川南地区受古沉积环境和古构造演化的影响,龙马溪组页岩在岩相、沉积亚相分布上具有较大差异,表现出极强的非均质性;深水陆棚亚相沉积为页岩气富集的最有利沉积相带。 |
| 关键词: 页岩气 页岩沉积亚相 沉积演化 川南地区 |
| DOI：10.3969/j.issn.1673-5005.2020.03.002 |
| 分类号::TE 121.1 |
| 文献标识码:A |
| 基金项目:国家科技重大专项(2017ZX05035)；西安石油大学博士科研启动基金项目(2014BS07) |
|
| Re-division and evolution of sedimentary subfacies of Longmaxi shale in southern Sichuan Basin |
|
PU Boling1,2, DONG Dazhong3,4,5, WANG Fengqin1,2, LIU Guizhen1,2, WANG Yuman3, HUANG Jinliang3
|
|
(1.School of Earth Sciences and Engineering, Xi 'an Shiyou University, Xi 'an 710065, China;2.Shaanxi Key Laboratory of Petroleum Accumulation Geology, Xi 'an Shiyou University, Xi 'an 710065, China;3.Research Institute of Petroleum Exploration ＆ Development, PetroChina, Beijing 100083, China;4.National Energy Shale Gas Research ＆ Development (Experimental) Center, Langfang 065007, China;5.Key Laboratory of Unconventional Oil ＆ Gas Resources, PetroChina, Langfang 065007, China)
|
| Abstract: |
| In order to identify the sedimentary characteristics of the organic-rich shale from the Longmaxi Formation of the Lower Silurian in the southern Sichuan Basin, a series of studies, including lithology, lithofacies, sedimentary structures, organic matter contents, mineral composition, biogenic fossils and logging responses, were carried out in this paper. The lithofacies and sedimentary subfacies were classified, and the sedimentary evolution model of Longmaxi shale in southern Sichuan Basin was established. The results show that:there are seven types of lithofacies developed in the Longmaxi shale, including graptolite-rich shale, carbonaceous shale, siliceous shale, calcareous shale, muddy limestone, silty shale and argillaceous shale. Three types of sedimentary subfacies were developed, including deep-water shelf, semi-deep-water shelf and shallow shelf. According to the physical condition of the graptolite, the sedimentary water depth was different in different geological ages. When the Longmaxi formation was deposited, through the Rudan stage to the Telychian stage, the sedimentary center gradually migrated from the Changning area to the north-west Weiyuan area. Three stages of sediments were deposited in the Weiyuan area, while there were only two stages of sediments deposited in the Changning area. It is concluded that there are great differences in the distribution of lithofacies and sedimentary subfacies of the Longmaxi shale in southern Sichuan Basin due to the influence of palaeosedimentary environment and paleotectonic evolution, showing strong heterogeneity. Deep-water shelf is the best favorable sedimentary subfacies for shale gas enrichment. |
| Key words: shale gas shale sedimentary subfacies sedimentary evolution southern Sichuan Basin |
|
|
|
|
|
|
