南极乔治王岛菲尔德斯半岛湖泊堆积物的物相组成特征及其环境意义  

CHARACTERISTICS OF MINERAL PHASE CONSTITUENTS AND THEIR ENVIRONMENTAL IMPLICATION OF LACUSTRINE DEPOSITS FROM THE FILDES PENINSULA OF KING GEORGE ISLAND,ANTARCTICA

作　　者：彭文世[1] 郑洪汉[1] 王冠鑫[1] 

机构地区：[1]中国科学院广州地球化学研究所

出　　处：《极地研究》1997年第2期119-127,共9页Chinese Journal of Polar Research

摘　　要：本文根据南极乔治王岛菲尔德斯半岛燕鸥湖、西湖和基太克湖三个堆积剖面物相组成与丰度的资料，讨论其物相组成特征、物质来源及其环境意义。研究结果表明，湖泊堆积物主要来自该岛广泛分布的火山岩。在南极地区干冷环境条件下，源区母岩所经受的风化作用以物理风化为主，化学风化微弱。高岭石、方解石丰度与年龄关系曲线在湖积层与冰碛层之间的陡削变化表明，相应的环境变化是突变式的，可能与这两种堆积物搬运方式的不同和冰碛物的保护作用有关。Mineral phase constituents of lacustrine deposits from the Fildes Peninsula of King George Island,Antarctica,are quite similar each other,but different in their contents. The outstanding feature of deposits is of great proportion of non crystalline matter and less in the species of crystalline minerals. Plagioclass (labradorite) is main phase in primary minerals of source rock with less quartz. Secondary minerals are mostly the clay minerals. K bearing minerals are completely lack in deposits. Obviously,all these can be assigned to being the mineralogical characteristics of meta basic rock source and show close genetic and inherited relationship in mineral phase constituents between lacustrine deposits and meta basic volcanic rock spreaded broadly at the peninsula. Among clay minerals,montmorillonite is dominant and kaolinite is less. There is a little difference in chemical compositions between lacustrine deposits and volcanic rock. The constituents of mineral phases change less with grain size. All these clearly prove that physical weathering of the parent rock is much stronger than the chemical weathering. The lacustrine deposit layer and glacial drift layer can be distinguished by the relation curves between the contents of kaolinite or calcite and ages,and their boundary ages are basically consistent with corresponding measured ages.

关 键 词：南极 湖泊堆积 物相组成 环境意义 

分 类 号：P512.3[天文地球—地质学] P931.7