Metallogenic model and discovery significance of the Chuakelaqian cryptoexplosion breccia type Pb-Zn deposit in the Qimantag metallogenic belt, Qinghai Province

There are many skarn, hydrothermal and porphyry type deposits which are closely related to Triassic granite and porphyry in Qimantag area of western East Kunlun metallogenic belt, Qinghai Province.A new type deposit, i.e., Chuakelaqian cryptoexplosion breccia type lead-zinc deposit, was discovered recently by vacancy prediction metallogenic theory.Based on a study of fluid inclusions and H-O-S isotopes, the authors found that there were two kinds of fluids in the Chuakelaqian deposit.One was middle-high temperature low salinity low density NaCl-CO₂-H₂O fluid and the other was low temperature middle salinity middle-low density NaCl-H₂O fluid.Metallogenic pressures of two types of fluids were different.This coincides with the key of cryptoexplosion and mineralization that pressure is suddenly released.Ore-forming fluids originated from the mixing of magmatic and meteoritic water and S originated from magmatic activity.Based on summary of deposit characteristics, it is considered that the deposit was closely related to porphyry. The metallogenic model of the deposit was built up in combination with porphyry metallogenic characteristics of A area in the Kaerqueka deposit. The opinion that there exists large potential in prospecting for porphyry type deposits in the Chuakelaqian area was put forward. The discovery of this deposit has important scientific and exploration significance for promoting the breakthrough of porphyry prospecting and the study on metallogenic regularity of porphyry in Eastern Kunlun area.