摘要
风火山盆地古近纪和新近纪沉积包括下部连续沉积的早始新世—早渐新世风火山群和早渐新世雅西措群,以及不整合其上的早中新世五道梁群。风火山地区的砂岩铜矿全部产于风火山群1岩组的灰(绿)色砂岩层中。采自风火山群1岩组含矿层和非含矿层中的3个磷灰石样品,分别获得了(22.5±2.3)Ma、(33.1±6.0)Ma和(28.0±3.6)Ma的裂变径迹年龄数据。其中33.1～28.0 Ma代表了该地区砂岩铜矿的成矿年龄.22.5 Ma则代表了成矿后构造热事件的年龄。风火山砂岩铜矿的成矿年龄处在其上覆的雅西措群沉积年龄范围内.显示砂岩铜矿是盆地早期沉积物压实脱水流体的产物。
The Paleogene and Neogene sediments in the Fenghuoshan basin include the continuously deposited early Eocene to early Oligocene Fenghuoshan Group and early Oligocene Yaxicuo Group in the lower part and their overlying early Miocene Wudaoliang Group. All the sandstone copper deposits in the Fenghuoshan area occur in gray （green） sandstone of the first formation of the Fenghuoshan Group. Three apatite samples collected from the ore-bearing and barren beds of the first formation of the Fenghuoshan Group yielded fission track ages of 22.5±2.3, 33.1±6.0 and 28.0±3.6 Ma respectively. Of these ages, the age of 33.1-28.0 Ma is the mineralization age of the sandstone copper deposits of the area, while the 22.5±2.3 Ma age is the age of the post-mineralization tectono-thermal event. The mineralization ages of the sandstone copper deposits are in the range of ages of deposition of their overlying early Oligocene Yaxicuo Group, indicating that the sandstone copper deposits are the product of compaction and dehydration of the early-stage sediments in the basin.
出处
《中国地质》
CAS
CSCD
2008年第2期293-297,共5页
Geology in China
基金
科技部“十一五”国家科技支撑计划项目(2006BAB01A06)资助
关键词
砂岩铜矿
成矿年龄
裂变径迹
风火山
sandstone copper deposit
mineralization age
fission track
Fenghuoshan
