华北板块南缘北东地区构造特征及矿井瓦斯主控因素

Structural Features and Main Mine Gas Controlling Factors in Northeastern Part of North China Plate South Margin

通过华北板块南缘北东地区的弧形构造特征、形成时代和瓦斯分布特征的研究,得出如下结论:1徐宿弧形构造限于丰沛断裂与蚌埠隆起北缘的五河断裂间,为形成于早三叠世后、晚侏罗世前的推覆构造;其形成与动力来源可能是扬子板块沿着郯庐断裂带向西或北西方向俯冲于华北板块之下的碰撞拼贴作用。2徐宿弧形推覆构造中和面外侧引张、内侧挤压的构造应力场是导致位于弧形内侧的宿东向斜内煤矿瓦斯富集、外侧闸河向斜瓦斯含量相对较少的主因之一;煤矿区内岩浆岩体(脉)的侵入改变了这种本应规律的瓦斯分布图案。岩浆活动和构造作用共同构建了华北板块南缘北东地区的构造和瓦斯分布图案。

Through studies on arcuate structural features, formation age and gas distribution characteristics in the northern part of North China Plate south margin came to the following conclusions：1. The Xuzhou-Suzhou arcuate structure is limited within the Fengxian-Peixian fault and Wuhe fault on north margin of Bengbu uplift, is a nappe structure formed after Early Triassic, before Late Jurassic;its origin and dynamic source are possibly from collision and collage of Yangtze plate subducted beneath North China plate along the Tancheng-Lujiang faulted zone westward or northwestward. 2. Structural stress field of Xuzhou-Suzhou arcuate nappe structure neutral plane extended outside flank and compressed inside flank is one of the major causations bring on coalmine gas concentration in Sudong syncline located inside of the arcuate structure, while less gas content in outside Zhahe syncline. Magmatic rock body （dike） intruded into coalmine area has changed the gas distribution pattern ought to be regular. Thus, magmatic activities and structural effects together constructed structures and gas distribution pattern in northeastern part of North China plate south margin.