The Quantitative Research Of The Relation Between The Configuration Of Fault-propagation Fold And The Depth And Form Of Detachment Fault

Previous studies established a mathematical model for the relationship between fault-propagation fold and detachment fault. This paper further calculates the depth of the lower flat using the blind balanced geologic section. In this model, five parameters are needed : backlimb angle 2 θ, interlimb angle γ, the structural high of anticline luthe width of anticline AB,the thickness of the layer upwards fault tip ho. Afterwards, a software had been programmed to carry out this mathematic model. According to the results of the explanation of balanced geologic section and the disposal of the earth's surface, we can apply this software to Fangdoushan and Qiyueshan area in South China. In the geologic section of Cizhuya anticline, we can get the deepness of flat,which was about 8.25km. This result explains that the flat is approximately located on the bottom of Cambrian stratum. It is consistent with the results of the explanation of balanced geologic section. Quantitative research of the relationship between the depth of fault and the shape of fold can provide new method for the research of structural oil and gas' accumulation and has prodigious help to the exploration of oil and gas.