Structural discrimination indexes of ordovician limestone top filling zones and determination method

Abstract

The invention relates to structural discrimination indexes of ordovician limestone top filling zones and a determination method, belonging to the field of structural discrimination indexes of water-containing geology and determination methods. Coal field-based ordovician limestone top filling zones, the buried depths of which are more than 300 m, are divided into three forms including a water-resisting filling zone, a weak water-resisting filling zone and a water-enriched zone; the water-resisting filling zone can be directly used as a water-resisting layer; the weak water-resisting filling zone can be utilized after being improved into the water-resisting layer through slurry ejection; discrimination and developing depths, namely determination of thicknesses, of the water-resisting filling zone and the weak water-resisting filling zone have great significance to mine lower coal group in the deep part of a coal field, the buried depth of which is more than 300 m, and prevent and control ordovician limestone water damage; the types of the ordovician limestone top water-resisting filling zones are divided according to the drilling unit water inflow q value, the underground drilling dewatering test Q value and the penetration test K value; and type discrimination index threshold values and determinations thereof are given. The structural discrimination indexes disclosed by the invention are obtained from conventional hydrological tests, and have the advantages of being relatively simple to obtain, easy to operate by field staffs, convenient for field application and practice and wide in application prospect.

Description

Technical field [0001] The invention relates to a water-bearing geological structure identification index and a determination method, in particular to a structure identification index and a determination method of the Ordovician ash top filling zone. Background technique [0002] Ordovician limestone has always been the upper strong aquifer in the North China coalfield area, and the main target of water hazards in the lower coal mining. And as the mining depth increases, the water pressure increases and the danger becomes greater and greater. According to estimates, the coal geological reserves of North China coalfields threatened by deep high-pressure Ordovician water (water inrush coefficient greater than 0.1 MPa / m) are about 15 billion tons. Therefore, how to achieve safe mining under pressure for the lower group of coal and reduce mining costs are the goals of exploration in North China coalfields in recent years. [0003] Before the new century, scholars mostly focused on th...

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Problems solved by technology

[0005] The purpose of the present invention is to provide a kind of identification index and determination method of the structure of the top filling zone of Austrian ash, and solve the problem of using drilling coring to o...

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