Research on Methods of Thickness Restoration of the Denuded Lower Cretaceous in Tanzhuang-Shenqiu Sag, Zhoukou Basin

Tanzhuang-Shenqiu sag,located in the central part of Zhoukou basin, a giant Mesozoic- Cenozoic Sedimentary basin at the southern margin of North China platform,is a secondary tectonic unit resulted from overlapping of two rifts of Mesozoic and Cenozoic,which experienced at least 6 differencial uplifting-subsiding since Yanshan period.These tectonic movements controlled formation preservation,thermal evolution of organic substances and generation,migration and accumulation of oil and gas.Five methods including seismic section, drilling formation layering, clay mineral,vitrinite reflectance and interval transit time were used to restore the degradated formation thickness and to render the development history of the basin.