摘要:咸化湖盆存在碎屑岩、化学岩及混积岩共生的沉积现象，但多类型沉积物有序分布的机制尚不明确。本文以渤南洼陷沙四上亚段为例，开展了咸化湖盆多类型沉积物有序分布及控制因素的分析，结果表明：渤南洼陷沙四上亚段低位域沉积期以碎屑岩沉积为主，湖侵域和高位域则出现化学岩与混积岩，由近岸到远岸呈扇体、砂岩滩坝、混积岩滩坝、碳酸盐岩滩坝、盐湖、半深湖及深湖有序分布；化学岩主要受水体环境控制，水体古盐度大于10‰是化学岩形成的基础，盐度和深度共同控制碳酸盐岩、膏岩以及盐岩分布，同时水体深度对不同成因类型的碳酸盐岩及碎屑岩分布也产生影响；碎屑岩主要受物源地貌控制，物源区位置及物源供应强度决定着碎屑岩的沉积位置和规模大小，同时古碳酸盐岩的发育影响着现今碳酸盐岩的发育位置；古地貌位置的高低及坡度的陡缓决定着砂体成因类型，同时古地貌还影响着生物礁生长及碳酸盐沉淀；咸化湖盆多类型沉积物有序分布受古水深、古盐度、古物源、古地貌的共同作用。
关键词: 咸化湖盆/
沉积物有序分布/
控制因素/
水体环境/
渤南洼陷
Abstract:Clastic, chemical and mixed sedimentary rocks coexist in saline lacustrine lake, but the mechanism that multiple type of sediments were distributed in order was not clear yet. Taking the upper part of 4th member of Shahejie formation（Be called Es4s for short）in Bonan sag as a case study, the sediments distribution characterization and its control factors in saline lacustrine lake were concerned. Results show that the low stand system tract of Es4s mainly develop clastic in Bonan sag. And chemical and mixed sedimentary rocks were developed in transgressive and highstand system tract. Fans, sandy beach-bar, mixosedimentite beach-bar, carbonate beach-bar, salt lacustrine, semi-deep and deep lacustrine were distributed orderly from nearshore to far-shore. Distribution of chemical rocks was controlled by water environment. And paleosalinity super than 10‰ was the basis of chemical rocks formation. The carbonate rocks, gypsum rocks, salt rocks were controlled by water salinity and depth. Moreover, water depth had effect on distribution of different types of carbonate rock and clastic rock. Distribution of classic rocks was mainly controlled by provenance and paleogeomorphology. The position and supply intensity of provenance determined sedimentation position and size of classic rocks, meanwhile development of paleocarbonate rocks influenced the development position of current carbonate rocks. Height and slope of paleogeomorphology determined sand body types and it also influenced formation of biogenetic-reef and chemical origin carbonate rocks. Ordered distribution of multiple type of sedimentary facies were benefited from the combined action of palaeowater depth, palaeosalinity, palaeoprovenance and palaeogeomorphology.
Key words:Saline lacustrine basin/
Ordered distribution of sediments/
Control factor/
Water environment/
Bonan sag
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