关键词: 斑岩型铅锌矿, 深部找矿, 矿化分带性, 成矿系列

Abstract: Prospecting for the peripheral and deep parts of old mines has been the focus for geological exploration at present and future.How to use the existing theories or combined with the actual results to achieve a breakthrough in the exploration for the peripheral and deep parts of old mines，which needs further study urgently.For a porphyry lead-zinc deposit in the Chengde City of Hebei Province，previous works focused on the porphyry body and its contact zone with carbonate rocks (skarn-type deposits)，ignoring study on ore bodies in structural fractures of outer zone or deep copper molybdenum ore bodies.Recently geological surveys indicate that the geochemical anomalies are developed in this area for lead，zinc，silver as well as other elements，and the polarization anomalies are consistent with the extension of controlled orebodies.Drilling results show that hydrothermal vein-type lead-zinc-silver rich ore bodies are distributed in quartz sandstones around the porphyry body， and copper-molybdenum ore bodies are present in the deep parts.Analysis results of core halo samples indicate that the deposit is characterized by vertical mineralization.In this paper，it is pointed that these characteristics are same as porphyry deposit series and show great prospecting potential through study on regional geology，mining area geology，alteration of surrounding rocks， and mineralization zoning as well as compared with typical mineralization zoning models of porphyry deposits.Thus，the prospecting directions are defined in this area that looking for lead-zinc-silver deposits in the periphery of the area，lead-zinc-silver deposits in the shallow parts of the rock body，and copper-molybdenum deposits in the deep parts.On this basis，two prospecting target areas were delineated in combination with geophysical and geochemical anomalies，which provided an important reference for predicting the prospects in peripheral and deep parts of porphyry-type lead-zinc polymetallic deposit as well as guiding future geological exploration work.

Key words: porphyry lead-zinc deposit, deep prospecting, mineralization zonation, metallogenic series