鄂尔多斯盆地多种能源矿产富集规律的比较

鄂尔多斯盆地蕴藏着丰富的石油、天然气、煤炭和铀。在纵向上,石油、煤和铀矿主要分布在侏罗系,天然气主要分布在二叠和奥陶系,天然气位于石油和铀矿的下方,并紧邻石炭-二叠系煤系的上下层位。在平面上,石油位于盆地中南部,铀矿位于盆地边部(北部和西缘),天然气和煤炭资源在全盆地均有分布,可采的煤炭位于盆地边部。在加里东晚期至海西期的古风化壳上形成的古岩溶和广泛分布的大型辫状河三角洲前缘沉积分别控制了下古生界和上古生界天然气的分布,构造转折期和古气候控制了聚煤期,氧化-还原环境控制了铀矿的聚集。盆地多能源成矿演化具有明显的阶段性,具有商业价值的能源矿产聚集成藏的顺序依次为:煤→铀→气→油。伊陕斜坡是进行石油、天然气、煤炭和非常规天然气勘探的理想地区;天环坳陷、西缘逆冲带可开展油-气-煤-铀矿的联合勘探;伊盟隆起、渭北挠褶带和晋西挠褶带可进行煤炭、煤层气和铀矿的协同勘探。

Comparison of enrichment patterns of various energy resources in Ordos basin

Ordos basin is prolific in oil, gas, coal and uranium resources. Vertically, oil, coal and uranium distribute mainly in Jurassic, while gas distributes mainly in Permian and Ordovician; natural gas is located below oil and uranium, and closely above and/or below the Permo-Carboniferous coal measures. Laterally, oil distributes in the central and southern ports of the basin, uranium deposits are located in the northern and western edges of the basin, natural gas and coal distribute in the whole basin, and recoverable coals distribute in the basin margin. Gas distributions in Lower and Upper Paleozoic have been controlled by the palaeokarsts formed in the late Caledonian to Hercynian fossil weathered crusts, and the widely distributed large braided river delta front sediments, respectively. The accumulation of coal has been controlled by the turning stage of tectonism and palaeoclimate, and the enrichment of uranium has been controlled by oxidation-reduction environment. The minerogenic evolutions of various energy resources in the basin are characterized by their obvious phasic development, and the commercial energy resources have been accumulated in a sequence of coal→uranium→gas→oil. Yishan slope area is favorable for exploration of oil, gas,coal and unconventional gas; Tianhuan depression and the thrust belts on the western edge of the basin are favorable for joint exploration of oil, gas,coal and uranium;Yimeng uplift and Weibei and Jinxi flexural fold belts are favorable for joint exploration of coal, coalbed methane and uranium.