ABSTRACT
The formations of Dongpu depression, from the later to the earlier, are Pingyuan Fm. of Cenozoic Quaternary, Minghuazhen Fm. and Guantao Fm. of Neogene, Dongying Fm. and Shahejie Fm. of Paleogene, Carboniferous-Permian Fm. of Mesozoic and the upper Paleozoic, and Ordovician Fm. of the lower Paleozoic. Shahejie Fm. is divided into four members, in increasing age order, Member 1 (ES1), Member 2 (ES2), Member 3 (ES3) and Member 4 (ES4), respectively (the left of Fig. 1). ES2 is subdivided into the upper ES2 and the lower ES2, among them, the lower ES2 is the target member with the thickness between 180 m and 200 m. The lithologic profile displays a set of cross section between sandstone and mudstone. The dominant mudstone colour of upper profile is gray, and purple for lower profile. Sandstone on this profile is characterized by pure sand, good physical properties, and low resistivity. The lower ES2 is composed of four sand groups, among of which the 2nd, the 3rd and the 4th sand groups have well-developed sandstone with a stacking thickness ranging from 10 m to 60 m. Sandstone occurs generally as lens and shows large lateral
1 INTRODUCTION
Sequence stratigraphy theory and its research method has been accepted by domestic and foreign petroleum geology geologists because of its practical application, therefore it becomes the core of the lithologic reservoir exploration technology (Cross, T.A. 1994, Deng, H.W. 1995). Previous research on sequence stratigraphy adopted many analysis methods, but the effect is not ideal (J.L., Zhang, 2009). INPEFA is briefly introduced in this paper, its curve trend can reflect various grades of sequence boundaries and the rhythm of sedimentary cycle changes, so hidden geological information can be shown (Berger, A. 1988). Hereby, isochronous stratigraphic correlation is established. The effectiveness and accuracy is verified in W79 Block.
