论文部分内容阅读
利用野外露头和钻井岩心资料,对铜川地区深湖沉积油页岩的岩性特征、纵向分布、平面展布及地层产状进行分析,明确深湖沉积油页岩特征。研究认为铜川地区深湖沉积油页岩位于鄂尔多斯盆地渭北隆起带内,构造隆起向北间距逐渐增大,幅度逐渐减小;发育了面积广泛、沉积厚度巨大的深湖沉积的油页岩;油页岩垂向上为一连续厚层泥岩,具重力流浊积岩夹层,分布稳定,厚层泥岩中见多层凝灰质泥岩,发育在晚三叠系延长组,成层性好,地层发育,面积广,含有凝灰质,为延长组第二段与第三段地层的分界线;铜川地区宜君—金锁关一线为一断裂带,在断裂带附近地层产状较陡,从断裂带以东以西野外露头和探井看,地层倾角较小,多小于10°。研究结果表明油页岩的发育特征、分布范围、厚度、有机质丰度受古气候和深湖沉积发育特征及深湖沉积相控制。
Based on the data of outcrops and drilling cores, the lithologic characteristics, longitudinal distribution, plane distribution and formation of sedimentary shale in the deep lake of Tongchuan area are analyzed, and the characteristics of oil shale in deep lake are clarified. The study shows that the deep-lake sedimentary oil shale in Tongchuan area is located in the Weibei uplift zone of the Ordos Basin and the tectonic uplift gradually increases in northward distance and gradually decreases in amplitude; oil shale deposits with extensive area and huge thickness deposited in deep lakes are developed; Oil shale is vertically continuous thick mudstone, with gravity flow turbidite interlayer, the distribution is stable, see the thick mudstone multi-layer tuffaceous mudstone, developed in the late Triassic Yanchang Formation, good stratification, stratigraphic development, The area is broad and contains tuff, which is the dividing line between the second and the third strata of Yanchang Formation. The Yijun-Jinshuguan line in Tongchuan area is a fault zone, and the formation near the fault zone is steeper. From the fault zone East outcrops and exploration wells to the west, stratum dip smaller, more than 10 °. The results show that the developmental characteristics, distribution range, thickness and organic matter abundance of oil shale are controlled by paleoclimate, deep-lake sedimentary development and deep-lake sedimentary facies.