Pingzhuang-Machang Basin Geological Structure And Evolution Characteristics

Through field geological survey, sample testing, map compilation, comprehensive analysis of geological information, the basin’s geological structures and characters were revealed. The study revealed that there were four sets of faults:NE、NNM、WNW、NNW、nearly EW、nearlyNS faults and three sets of folds:NNE、WNW and NNW folds; The Pingzhuang-machang basin was divided into two second structure units that Pingzhuang depression and Ershijiazi depression; Pingzhuang-Machang basin was a graben fault basin in Jinfotang period and half graben fault basin after Jinfotang period. Balihan fault controlled basin formation and evolution; The structures of previous basin formation was mainly EW and NE direction structure system; The structures of basin formation was mainly NNE direction extensional system; Basin evolution experienced two development stages-double wall rift and single wall rift; It existed angle unconformity between the Fuxin formation and Sunjiawan formation; Sunjiawan depositional period was under strike-slip stretching stress field;In the Miocene sedimentary period the uplifting of the basin made it died out. On this basis, the article described that the sedimentary environment was controlled by geological structure.