OCCURRENCE AND CORRELATION OF VARIOUS ENERGY RESOURCES IN THE ORDOS BASIN

The Ordos Basin is rich in oil,natural gas,coal,coalbed methane and sandstone-type uranium deposits.Oil pools mainly locate in Triassic and Jurassic in the south.Natural gas vertically situates beneath oil pools in the north.Coal measures are widespread.The margin of the basin is characterized by sandstone-type uranium deposits and abundant in coalbed methane.Geneses of various energy resources have been defined by source investigations.Oil is mainly originated from Mesozoic lacustrine source rocks.Natural gas derives from Upper Paleozoic coal series as well as marine limestones.Coalbed gas is formed during the coalification of coal accumulation centers.Uranium source may be offered by medium-acidic granite and uranium-bearing formation.Timing and formation mechanism of these resources suggest that there are genetic relationships among them,especially the difficulty for Jurassic coal to form commercial oil accumulation,the contributions of coal to natural gas,the supplement of coalbed methane to deep basin gas and the reduction of natural gas to uranium deposits.