塔里木盆地古近纪岩相古地理  

Lithofacies palaeogeography of the Paleogene in Tarim Basin

作　　者：邵龙义[1] 何志平 顾家裕[3] 罗文林[1] 贾进华[3] 刘永福[4] 张丽娟[4] 张鹏飞[1] 

机构地区：[1]中国矿业大学(北京)煤炭资源教育部重点实验室及资源与地球科学系,北京100083 [2]振华石油控股有限公司,北京100031 [3]中国石油勘探开发研究院,北京100083 [4]中国石油塔里木油田公司石油勘探开发研究院,新疆库尔勒841000

出　　处：《古地理学报》2006年第3期353-364,共12页Journal of Palaeogeography：Chinese Edition

基　　金：国家自然科学基金(40172050);教育部新世纪优秀人才支持计划成果基金资助

摘　　要：古近纪是塔里木盆地由海向陆转化的时期。当时该区的海侵来自研究区西侧的古地中海分支,物源则主要是盆地北部的南天山以及南部的昆仑山,沉积中心在库车坳陷西部以及塔西南坳陷带的西部。古新世—始新世早期(库姆格列木群沉积期)在盆地北部库车坳陷发育砾岩、砂岩、碳酸盐岩及膏盐岩,沉积环境有滨岸、湖、潮坪及扇三角洲等,塔西南坳陷以碳酸盐岩和膏岩为特征,从东到西发育开阔台地、近岸局限台地、蒸发盐台地、辫状河三角洲环境等,二者之间即在塔北隆起及北部坳陷带位置为宽阔的古隆起区。始新世晚期—渐新世(苏维依组沉积期)整个盆地以滨浅湖为主,发育粉砂岩与泥岩互层沉积,塔西南坳陷虽然仍发育多个海相层,但海水的影响明显比始新世早期弱,当时主要古地理单元有海湾湖、滨浅湖、扇三角洲和辫状河三角洲。总体上,塔里木盆地在古近纪经历了早期以扇三角洲为主的浅水环境到晚期的滨浅湖及海湾湖环境,古近纪研究区的古气候以热带—亚热带的干旱气候为主。The Paleogene is a period when the Tarim Basin transformed from a marine influenced to a non-marine influenced basin. The marine transgression in the basin was from the northern branch of the Tethy to the west. The sediment provenances were the old southern Tianshan to the north and the old Kunlun Mountains to the south, and the depocenters were located at the western Kuqa Depression and the western Southwestern Tarim Depression. From the Paleocene to the Early Eocene （during the deposition of the Kumugeliemu Group and its equivalents）, the Kuqa Depression was developed with shoreline, lagoon, tidal flat and fan-delta environments, and was lithologically dominated by conglomerates, sandstones, carbonates and gypseous rocks. The Southwestern Tarim Depression was developed with open platform, nearshore restricted platform, evaporate platform, and braided delta environments, and lithologically dominated by carbonates, gypseous rocks and coarse sandstones. These two old depositional depressions were separated by an extensive palaeo-uplift which coincided with the current Northern Tarim Uplift and Northern Depression structural zones. From the Late Eocene to Oligocene （during the deposition of the Suweiyi Formation and its equivalents）, the entire Tarim Basin was mostly submerged and was developed with a wide coastal to shallow lake that received deposition of interbedded siltstones and mudstones. The marine successions were restricted to the western corner of the Southwestern Tarim Depression and marine influence became less evident than that in the Paleocene to the Early Eocene. The paleogeographic units of this period were mainly estuarine, lagoon, littoral-shallow lacustrine, as well as braided deltas.On the whole, during the Paleogene, the Tarim Basin experienced a shallow water environment dominated by fan-deltas of the early phase and the littoral to shallow lacustrine environment of the late phase, with a tropical to subtropical arid paleoclimate.

关 键 词：塔里木盆地 库车坳陷 塔西南坳陷 古近系 古地理 沉积相 

分 类 号：P618.130.1[天文地球—矿床学]