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塔里木板块西北柯坪地层区中-上奥陶统萨尔干组的分布和相变受控于当时西浅东深的海底深度差异。萨尔干组的厚度10米左右,为富含有机物的黑色页岩并夹少量灰岩薄层或透镜体。位于研究区西南的伽师西克尔剖面缺失大部分奥陶纪地层,上奥陶统铁热克阿瓦提组碎屑岩不整合于下-中奥陶统鹰山组灰岩之上,中-晚奥陶世的大部分时段属于暴露海面的剥蚀区;北部乌什的亚科瑞克剖面无萨尔干组岩性单元,为红色居多且粒度偏粗的碎屑岩夹白云岩薄层,属于近岸带碎屑岩为主的沉积区。西克尔向东北延伸150km至柯坪羊吉坎亦无萨尔干组,与萨尔干组同期沉积的地层在此表现为大湾沟组上部浅海灰岩的相变,且与上奥陶统桑比阶坎岭组偏深水相的红色薄层含泥瘤状灰岩之间呈整合接触;由西向东出露于柯坪苏巴什沟、柯坪大湾沟、阿克苏四石厂3个剖面的萨尔干组黑色泥页岩指示典型的滞流盆地相,而夹含于萨尔干组下部和上部的薄层灰岩之微相特征差异甚为显著,表现为该组下部可见数层密集砂屑颗粒形成泥粒状灰岩或颗粒灰岩,可解释为西部相邻的浅海碳酸盐岩台地区灰岩经重力流搬运后的再沉积;而该组上部含生屑泥状灰岩则属滞流盆地相区类似于黑色页岩环境的正常沉积。从羊吉坎灰岩台地到苏巴什沟滞流盆地相之间距离仅20余千米,坡度偏大是导致重力流形成的主要原因。
The distribution and transformation of the Meso-Upper Ordovician Salkan Formation in the Keping Formation in the northwestern Tarim plate are controlled by the shallow depth of the ocean in the shallow and deep east-west at that time. Salkan group of about 10 meters in thickness, organic-rich black shale and a small amount of limestone sandwiched between lens or lens. Most of the Ordovician strata are missing from the Jiashi-Kecker section in the southwest of the study area. The Upper Ordovician Tiekeke Awati Group clastic rocks are not integrated with the Lower-Middle Ordovician Yingshan Formation limestone. Most of the Late Ordovician period belonged to the denudation area exposed to the sea surface. There was no lithological unit of the Salkan Formation in the Yakekeke section of the Wushi area in the north, which was the thin layer of clastic rock dolomite with the most red and coarse grain size, Belongs to the coastal zone clastic rock depositional area. The extension of the west Kerr to the northeast 150km to Keping Yang Jikan nor the Salkan Group, strata deposited in the same period with the Salkan Group show the phase change of the upper part of the Dawanggou Formation shallow sea limestone, Systemic Cambrian ridge group of deep water phase of the red thin layer of mud-bearing limestone was integrated contact; from west to east exposed in the Keping Su Basu ditch, Keping Da Wangou, Aksu four stone factory 3 The profiles of the Salkan black mud shale indicate a typical lacustrine basin facies, and the thin-bedded limestone sandwiched between the lower and upper parts of the Salkan group has a significant difference in microfacies characterized by the lower part of the group Several layers of dense sandstone particles formed as granular limestone or granular limestone, which can be interpreted as the re-deposition of limestone in the shallow marine carbonate platform adjacent to the western China by gravity flow. In the upper part of the group, Limestone belongs to the normal sedimentary facies of the stagnant basin similar to the black shale environment. The distance between the phases of the Yishikan limestone platform and the Subas ditch stagnant basin is only about 20 km, and the large gradient leads to the formation of the gravity flow.