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鄂尔多斯盆地奥陶纪中央古隆起是盆地内的重要油气聚集区,其成因一直是大家关注的热点.利用丰富的钻井资料对古隆起中东部地区中奥陶统马五段地层的沉积特征进行详细的分析,编制出了马五段各层段的厚度等值线图,圈出了各时期的沉降中心位置,发现在马五8~马五5时期,沉降中心基本以向南迁移为主,伴随着一定程度的向西迁移;在马五43到马五41时期,沉降中心以向西的迁移为主,伴随微弱的向南迁移.这种迁移过程支持鄂尔多斯盆地西、南缘在奥陶纪时发育双前陆盆地,“L”型中央古隆起是在早-中奥陶世时受该双前陆盆地前缘隆起相互叠加的影响.
Ordovician Central Ordovician paleo-paleo-uplift is an important oil and gas accumulation area in the basin, and its origin has always been the focus of attention. The sedimentary characteristics of the middle Ordovician Member Ma5 in the Middle Proterozoic uplift are described in detail with abundant drilling data , The contour map of the thickness of every section of Ma5 section was drawn out and the center of subsidence of each period was shown. It was found that in the period of Ma5-8 ~ Ma5 5, the subsidence center was basically dominated by southward migration, Accompanied by a certain degree of westward migration. During the period from MA535 to MA541, the subsidence center was mainly migrated westward with slight southward migration, which supported the migration of the western and southern Ordos Basin during the Ordovician period In the dual-foreland basin, the “L” -type central paleohigh is influenced by the superimposition of the uplift of the dual foreland basins during the Early-Middle Ordovician.