白龙江地区逆冲推覆构造及其与金矿的关系

白龙江地区的逆冲推覆构造体系是由亚尔玛-舟曲后缘逆冲带、波海-白依-迭部-武坪逆冲带、西倾山-武坪南中间推覆带、玛曲-南坪前缘挤压逆冲带及光盖山-迭山北麓拉伸盆地、尕海-郎木寺沉降盆地等六个基本构造单元组成的。逆冲作用导源于华力西-印支期以来特提斯洋壳及印度板块向中朝地块的后退式俯冲作用，因而导致了陆壳边缘的华力西-印文褶皱带（南秦岭）、由北向南扩展的前展式逆冲推覆构造的形成，并造成了岩浆活动带及金矿成矿带向南迁移，依次形成了青稞崖-亚尔玛-舟曲印支期浅成钙碱性岩浆活动带及燕山期中低温浅成微细浸染型砷金矿化带；波海-拉尔玛-白依燕山早期钙碱性超浅成次火山、岩浆活动带及喜山早期中低温、超浅成-热水动力隐爆式微细浸染型金矿化带；玛曲-南坪燕山末期岩浆活动带及喜山中晚期中低温热液超浅成-热泉型金矿化带。

THRUST NAPPE STRUCTURE AND GOLD MINERALIZATION IN BAILONG JIANG AREA

The thrust nappe structure system in the Beilongjiang area is composed of six basicstructural units，i．e. Yaerma─Zhouqu thrust zone， Pohai─Baiyi─Wuping thrust zone，Xiqing mountin─south of Wuping nappe zone，Maqu─Nanping thrust zone，tensional basinin the northern foot of Guanggei mountin and Gahai─Langmusi basin。 The thrusting restiltsfrom muItiple subductions of ocean crust of Tethys and Indian plate beneath Sino─Koreanplate since Hercinian─Indosinian, which produce the Hercinian─Indosinian folded belt in themargin of continent crust（south Qinling） and southward imbricate thrust nappe structures.Itis formed that magmatic zones and gold mineralization zones migrate southwards in time andgenetic type ， including, in order，Qingkeyan─Yaerma─Zhouqu Indosinian hypabyssal calc─alkali magmatic zone and Yanshanian mid─epithermal fine disseminated As─Au mineral-ization zone ， Pohai─Laerma─Baiyi early Yanshanian calc─alkali stiperhypabyssal subvol-canic and magmatic zone and early Hymalayan mid─epithermal hotwater cryptoexplosion─type fine disseminated gold mineralization zone，Maqu─Nanping latest Yanshanian magmaticzone and mid─late Hymalayan mid─epithermal hydrothermal and hot─spring─type goldmineralization zone.