Abstract:
To carry out regional geochemical studies in coordination with 1∶50,OOO-scale regional geological survey work is important for raising the levels of regional geological studies and regional mineral resource prediction and evaluation.The results obtained through regional geochemical studes in western Henan show that low-density regional geochemical rock surveys coupled with geochemical studies on special subjects such as stratigraphy,magmatic rocks, structures and mineral deposits are not only conducive to providing a geochemical basis for the in-depth study and solution of problems concerning basic geology,e.g.the relations of the nature and differences of regionsl crust to tectonics,stratigraphic correlation and division,reconstruction of protoliths of metamorphic rocks,origin of volcanic rocks and their stuctural setting during their formation,and origin and geochemical types of granites,but also useful for the study of regional metallogenic characteristics and pointing to a direction in mineral resource prediction and evaluation,e.g.in aspects of the relations between regional structure and metallogeny,metallogenic specialization of granites and criteria for evalution, characteristics of regional spatial distribution of known mineral deposits and study of regional geochemical anomalies.Owing to limited space,this paper only summarizes part of the problems.Besides,this paper also puts forwards a preliminary plan for field work, i.e.to undertake geochemical study while carrying out regional surveys.