焦坪侏罗纪煤系及其油气展布

THE DISTRIBUTION OF STRATA AND OIL-GAS IN JURASSIC FORMATIONS OF JIAOPING MINING AREA, SHAANXI PROVINCE

焦坪矿区油气显示规律与煤系分布关系密切。该矿区主要可采煤层4_(-2)煤层存在4个厚煤中心,矿区油气显示主要存在于聚煤中心带上、下部的砂岩层中,特别是煤层上部的延安组和直罗组砂岩层中。油气分布主要与延安组的厚度,4_(-2)煤层厚度,延安组和直罗组中、粗粒砂岩厚度,煤系成熟度和上覆地层厚度等因素有关。构造条件对烃类的影响较小,只在上述条件决定的范围内起作用。

There are some close relations between strata and oil distributions in Jiaoping coal bearing series. The major oil and gas shows were in the sand strata above and/or below the high-thickness coal areas. There are 4 such areas in the mining area. The oil and gas distribution in the coal bearing series could be further related to the thickness of Yanan formation (major coal bearing formation), sandrock of Yanan & Zhilou (over the Yanan) formations, all overlay formations of the coal bearing series, and to the rank of the organic matter. Structure form in the area is only secondary influence element of the distribution.