Conodont Thermal Maturity Assessment of Northern and Central China

John F. Baesemann, H. Richard Lane, Zhi-Hao Wang

Conodont thermal maturity (CAI) was used as an exploration tool to rapidly and inexpensively survey the thermal maturity of northern and central Chinese basins. Wang studied Ordovician-Triassic conodonts from regional well and outcrop material to develop a database from which an Ordovician-Triassic CAI map was developed. Four levels of thermal maturity have been mapped with each level having a unique color. The areal extent of the various colored regions is based on CAI data in conjunction with geological considerations. Also, areas of structural complexity and/or igneous activity have been assigned a unique color to highlight them because they served as heat sources that influenced local conodont thermal maturity. Additionally, more detailed time-slice maps of this infor ation were generated that display each data point and it's pertinent information (well or outcrop, age, and CAI value). The computer program allows flexibility in generating maps at different scales, limiting coverage to specific areas or creating different time-slice combinations. More conodont or other thermal maturity data or other types of information can be added to the database and displayed on maps.

By studying existing conodont collections housed in various Chinese museums, institutes, universities and oil companies, sample collection and preparation time and cost were avoided. Study time and cost were also minimal because the CAI method is simple and quick to use. Additionally, useful biostratigraphic data were also obtained.

AAPG Search and Discovery Article #91020©1995 AAPG Annual Convention, Houston, Texas, May 5-8, 1995