The Occurence Of Coal Seam And The Coal Accumulation Law In Alike Mining Area

The Carboniferous-Permian coal-bearing belt,loacted in the western section of the North Qilian Mountain,is an important coal-bearing region in the northeastern part of Qinghai Province.In recent years,with the increase in coal exploration and investment,the comprehensive exploration of the coal-bearing belt in the western part of the North Qilian Mountains has improved.Some mining areas with good prospects have submitted census,detailed inspection and verification reports.But the exploration and research of the entire coal-bearing belt are still low.Most of the relevant research results are based on a macroscopic study of a certain"zone"or"region".And the representative reaserch in mining area scale is rare.The Alike mining area is located in the Carboniferous coal-forming center in the western part of the North Qilian Mountains.It is typical of the Carboniferous coal-forming types in the western part of the North Qilian Mountains.Coal seam,coal quality and coal accumulation characteristics were carried out in Alike mining area.The study will provide basic information for future exploration and research.Based on the existing research and exploration,geological database was established.And the occurrence law of coal seam,and coal quality were carried out.The analysis of sequence stratigraphic framework,lithofacies-palaeogeography and coal seam occurrence was conducted.The characteristics and the formation conditions of coal seams were discussed;and the developmental characteristics of coal seams in different sedimentary systems were analyzed.The Chouniugou Formation was a shallow marine facies sedimentary environment;the Yanghugou Formation was the marine-continental transitional sedimentary environment.The sedimentation environment of the Carboniferous consisted of lagoon,tidal flat,carbonate platform,swamp,and the river-delta,and were divided into 11 sedimentary facies.The sedimentary model of the Carboniferous is"lagoon-tidal flat sedimentation model".The coal seam was mainly formed in the upper part of the vertical shallow sequence.The genesis of the shallow sedimentary sequence was mainly attributed to the vertical accumulation,the lateral accretion and the natural siltation.