THE CLASSIFICATION OF THE CONGYANG GRANITOID BATHOLITH INTO SUPERUNITS AND UNITS

On the basis of 1:50,000-scale regional geological surveys of the Congyang County Sheet and the Tanggou Township Sheet, an attempt has been made to classify the granitoid intrusion in the area into superunits and units. The author establishes the Congyang batholith and the Luojialing and Chengshan superunits. The superunits that form the batholith exhibit a regular spatial distribution and have corresponding rock types and mineralization features. The Luojialing superunit is composed of the pyroxene diorite unit, monzonite unit and admellite unit. The Chengshan superunit consists of the quartz syenite unit, biotite-quartz syenite unit and porphyritic Kfeldspar granite unit. In the geological history of as long as 3000 to 4000 Ma, magmatic activity occurred very frequently, which was obviously manifested by magmatic intrusion. The magmatic rocks are mainly of anatectic origin. The batholith is very similar to the Ceno-Mesozoic South China granitoids and the coastal batholiths of Peru in the circum-Pacific domain in respect to some main characteristic parameters, so it belongs to a typical I-type granitoid batholith.