Abstract：The mathematical simulation method of N-layered variable density model, which is used for the inversion of crustal fine structure, is different from currently used gravity inversion method for medium with single interface and constant densit}t, According to this method，the part consisting of crust and upper mantle is taken as a conti-nuous medium model made of N-layered variable density media, where the interface shaves are arbitrary and vertical density variation can be expressed by a density-depth function, called cubic spline functionin the paper, Then, objective function F is formed by summing up the squares of the deviations between theoretical gravity anomalies and corresponding observed gravity anomalies at observation points. F is the function of model parameterζk.Using optimization method，F can be minimized to get the best fitting between the theoreticalcurve and the real one，and the d0pth variations of different interfaces can be determined, then, 7 interfaces in the part consisting of crust and upper mantle in Jiangsu-Zhejiang-Anhui area, which accord with interfaces of’known data, were found using mathematical simulation method of N-layered variable density model, Hefei-Ningguo profile which was interpreted geologically and geophysically is given in the paper, and the isobath map of g2 interface, corresponding to the top surface of Chinglong limestone deposited in Indo-Chinese epoch, is also shown in the paper, The tectonic analysis drew a conclusion; top of Chinglong lime-stone is one of the major hydrocarbon exploration targets in this area， and the rise-depression zone (or two depressions and one rise) along the northwestern tectonic axial direction is the most favourable zone for hydrocarbon aceumulation.
收稿日期: 1986-09-29
引用本文:
陈胜早. N层变密度模型数学模拟法在苏浙皖地区的应用[J]. 石油地球物理勘探, 1987, 22(3): 237-248.
Chen Shengzao. The mathematical sim ulation method of N-layered variable density model is applied to JZA area. OGP, 1987, 22(3): 237-248.
