古地面研究在金刚石原生矿找矿中的意义──兼谈贵州金刚石的找矿前景

Importance of Paleosurface Analysis in Primary Diamond Search and Potentiality of Diamond Deposits in Guizhou

任一地区开展任一矿种找矿必须具备两个前提，一是成矿条件，二是成矿后的保存条件。就金刚石而论，作为幔源火山作用产物的金刚石原生矿的产出和成矿期古地面间存在密切的空间联系，矿床的保存与否和保存程度与古地面的剥蚀程度有关，故研究成矿后古地面的剥蚀一残存状况对金刚找矿具有重要意义。

It is necessary for any ore-searching works anywhere that there shouldbe two premises, i. e. ore-forming process and ore-preserving conditions. In terms ofprimary diamond dePOsits as a result of mantle-derived volcanic activity, there mustbe a close link spatially between diamond dePOSits and palessurface in ore-forming period and the preservation of diamond dePOsits must closely associates with the denudedextent of the Paleo-suffece. Guizhou is a good diamond-forming province, in whichthe known primary diamond deposit formed in Caledonian, but the erosion of Caledonian palessurface is so extreme that the known primary diamond deposit in Maping,Zhenyuan county is just consists of many small lamproite dikes and sills belonging toroot phase. However, the denuded extent of Caledonian paleosurface in Guizhou, especially in Eastern Guizhou where the geological environment for formation of diamond is ideal is not uniform and somewhere the paleosurface is still preserved well. Sothe author considers that where the late Paleozoic cover exists and there are additionaldiamond-hunting indicators, there is a potentiality of having researched primary diamond deposit.