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早古生代鄂尔多斯地块经历了混合型缓坡→清水型缓坡→镶边陆架末端陡倾的缓坡→奥拉槽蒸发岩台地的发育历程，相应发育了５个超层序，分别形成于早寒武世中寒武世早期（下Ｓａｕｋ），中、晚寒武世（中Ｓａｕｋ），早奥陶世冶里亮甲山期（上Ｓａｕｋ１），早奥陶世马家沟期（上Ｓａｕｋ２）和中奥陶世（下Ｔｉｐｐｅｃａｎｏｅ）。以中奥陶统底部的巨大不整合为界，可以划分出Ｓａｕｋ和Ｔｉｐｐｅｃａｎｏｅ两个超层序组。超层序和超层序组边界的形成与构造沉降速度突然变化、构造运动相联系。在寒武系识别出８～１０个层序，其中６～８个Ⅰ型层序，２个Ⅱ型层序，层序性质具有区域性和某种全球可对比性。经对比，寒武纪的海平面变化大多数周期具有全球变化的同一性，仅徐庄期频率高而崮山期频率低。早奥陶世构造活动弱，高频层序发育，含１８～２４个高频层序，合并为３～４个层序组；晚奥陶世具有５～６个层序周期，海平面变化总体趋势具有全球性，层序周期具有可对比性。根据地球化学分析，烃源岩主要与张夏组、马家沟组有关的密集段和与乌拉力克组有关的复合密集段相联系。良好的储层包括与不整合相关的古喀斯特、ＴＳＴ和ＨＳＴ的碳酸盐岩隆、生物碎屑滩和ＬＳＴ的浊积岩、ＬＳＴ底部和ＨＳＴ顶?
The Ordos block of Early Paleozoic experienced a series of gentle ramp → clear gentle ramp → gently steep gentle slope → the development of Eolaotian evaporite platform. Five super-sequences were developed, which were formed in the middle Cambrian Early Early Wuchu (Lower Sauk), Middle-Late Cambrian (Middle Sauk), Early Ordovician Yeliangshan Period (Upper Sauk1), Early Ordovician Majiagou Period (Upper Sauk2) and Middle Ordovician (Under Tippecanoe). Based on the huge unconformity at the bottom of the Middle Ordovician, two super-sequence groups, Sauk and Tippecanoe, can be distinguished. The formation of super-sequence and super-sequence group boundary is related to the sudden change of tectonic subsidence velocity and tectonic movement. In the Cambrian, 8 to 10 sequences are identified, of which 6 to 8 are Type I and 2 Type II sequences, and the sequence properties are regional and some globally comparable. By comparison, most cycles of the Cambrian sea level change have the same global change. Only the frequency of Xu Zhuang period is high but the frequency of Ju Shan period is low. The Early Ordovician tectonic activity was weak and the high frequency sequence developed with 18 ~ 24 high frequency sequences and merged into 3 ~ 4 sequence groups. The Late Ordovician had 5 ~ 6 sequence cycles and the sea level change The overall trend is global, and the sequence cycles are comparable. According to geochemical analysis, the source rocks are mainly related to the dense sections related to Zhangxia Formation and Majiagou Formation and to the compound intensive sections associated with the Ulalik Formation. Well-developed reservoirs include paleokarst, TST and HST carbonate rocks, bioclastic beaches and LST turbidites associated with unconformity, bottom of LST and top of HST?