商城岩体侵位对杨山煤系构造格局的影响  

Effect of Intrusion of the Shangcheng Granite Body on Structural Framework of the Yangshan Coal-Bearing Series,the Beihuaiyang Area,China

作　　者：曹代勇[1] 占文峰[1] 李小明[1] 

机构地区：[1]中国矿业大学煤炭资源与安全开采国家重点实验室,北京100083

出　　处：《中国矿业大学学报》2007年第3期320-324,共5页Journal of China University of Mining & Technology

基　　金：国家自然科学基金项目(40372075)

摘　　要：采用野外地质调查、构造要素测量和FLAC数值模拟等方法,探讨了北淮阳地区中生代岩浆活动对晚古生代杨山煤系变形-变质作用的影响.研究结果表明,商城岩体侵位所伴随的热力和应力,不仅显著促进煤的变形-变质进程,使煤级达到半石墨化阶段(Romax>8%),而且还对已有构造格局产生一定程度的改造.这种改造主要表现为区域构造线在岩体附近发生偏转、地层倾角增大、发育轴向与岩体边界近于平行的次级褶皱,从而导致杨山煤系构造格局复杂化并影响到含煤块段的赋存状况.FLAC数值模拟证实,岩体侵位施加放射状挤压应力在岩体周缘形成了一定宽度(约为岩体半径的1/5)的应力集中带,这是造成杨山煤系构造格局畸变的根本原因.The effect of Mesozoic magmatism on the deform-metamorphism of Paleozoic Yangshan coal-bearing series in the Beihuaiyang area, China, was investigated by field geological survey, structure factors measurement and FLAC numerical simulation. The results show that the heat and the stress resulted from the intrusion of Shangcheng granite body not only accelerate the coal deform-metamorphic process so as to enhance coal rank up to semi-graphitized stage （ Romax〉%）, but also change the former structural pattern to a certain extent. This change is mainly represented as that near the Shangcheng granite body the regional structure lines are deflected, the dip angle of strata enlarged and some second-order folds with axis parallel to the edge of intrusive body developed, which have made the structural framework of the Yangshan coal-bearing series complicated and affected the distribution status of coal-bearing blocks. FLAC numerical simulation confirms that the radial compressive stress from the intrusive body produces a stress concentration belt （approximately 1/5 radius of the body in width）in surrounding strata, which is the main reason of structure framework distortion of the Yangshan coal-bearing series.

关 键 词：杨山煤系 商城岩体 构造格局 FLAC数值模拟 

分 类 号：P554[天文地球—构造地质学]