南极文森峰的地层及沉积环境

STRATIGRPHY AND SEDIMENTARY ENVIRONMENT OF VINSON MASSIF, ANTARCTICA

文森峰的地层为一套古生代浅变质沉积碎屑岩系.通过与邻区的对比,作者将这套地层命名为文森峰组.它主要由杂色的石英砂岩、石榴子石石英砂岩组成,还有少量粉砂质泥岩、砾岩和大理岩,总厚度大于650m,自下而上可分五个岩性段.主要组成矿物为石英,并含有丰富的石榴子石,一定量的伊利石.砂岩分选性良好,成熟度高,原生沉积构造发育,属浅海滨岸相沉积.

A Palaeozoic low-grade metamorphosed sedimentary clastic sequence occurs in Vinson Massif, Antarctica. Based on field and laboratary study and comparison with adjencent rocks, the studied sequence is named as Vinson Massif Formation by the authors. The formation is mainly composed of variegated quartz sandstone, garnet quartz sandstone, and minor silty pelite, conglomerate and marble. It is over 650m in total thickness and can be divided into five lithologic members in ascending order. Hematite beds occur in the sequence. Mineralogically, the sequence is made up dominantly of quartz, subordinately of garnet and a certain amount of illite. The rocks show fine sorting and high maturity and display common sedimentary structures. Some evidences show that the Vinson Massif Formation is sedimented in neritic and littoral environment.