Types of thrust-nappe tectonics and their effects on coal reserves in Fujian coal-bearing area

Fujian coal-bearing area is mainly located in the depression region of southwestern Fujian Province, in which the exposed coal-bearing stratum principally consists of the middle Permian Tongziyan Formation.The thrust-nappe tectonics are widely developed in coal-bearing stratum, and could be classified into three types according to the characteristics of the fault and their impacts on coal-bearing stratum:basement thrust-nappe tectonics, interlayer thrust-nappe tectonics and cover thrust-nappe tectonics.In the basement thrust-nappe tectonics, old stratums thrust up over coal-bearing stratum, manifesting the covering of the thrust-nappe above coal-bearing stratum in a large scale on the ground and increasing the difficulty in investigation.By largely repeating of coal-bearing stratum and effectively thicken them, the interlayer thrust-nappe tectonics significantly increase the coal reserves per square area.On the contrary, as the upper wall of the cover thrust-nappe tectonics, coal-bearing stratum trend to be fragmented during the relative tectonic movement, definitely, then reduce the development value.Distinguished forming mechanisms contribute to distinct scales of those thrust-nappe tectonics.The basement thrust-nappe tectonics are the most widely distributed in depth, breadth and dynamics, and they completely change the abundance of coal resource in Fujian Province.The interlayer thrust-nappe tectonics are usually identified just within the mining area, while the size of cover thrust-nappe tectonics are even more limited.To draw a conclusion, it is necessary to carry out farther research on the exploration of coal resources underlying the basement thrust nappe.