摘要
铜陵地区岩浆夕卡岩具有如下特征：（１）既可产于有碳酸盐岩的环境，也可赋存于远离碳酸盐岩的辉石二长闪长岩或角岩中；（２）产出形态复杂多样，可呈透镜状、脉状、小岩床、岩瘤和不规则岩枝状或角砾岩筒等等；（３）与围岩界线截然，在易交代的大理岩中也一样。作为其围岩的大理岩可见港湾状熔蚀边及重结晶褪色边，辉石二长闪长岩出现被烘烤褪色边，夕卡岩边缘部出现矿物呈等轴状三联晶嵌生淬火边；（４）夕卡岩常常与辉石二长闪长岩紧密伴生，构成了特殊的“夕卡岩－富碱侵入岩对”；（５）夕卡岩发育有海绵陨铁结构，豆状构造、流动构造和气孔构造；（６）微量元素、稀土元素的特征与相关的火成岩相似；（７）有熔融包裹体，均一温度高达１０００℃以上；（８）其矿物组成、化学成分与接触交代夕卡岩无明显差别。岩浆夕卡岩是深部中酸性硅酸盐岩浆演化过程中形成的夕卡岩浆冷凝结晶的产物。
Magmatic skarn in Tongling area possesses the following characteristics. (1) It can be found either in or far from carbonatic rock. (2) It occurs as lentiform, vein, sill, knob and others irregular shapes. (3) Its boundary with the surrounding rock is clear and sharp, even in the easily replaced marble. (4) It is closely in space to the alkali gabbrodiorite and formed typical “magmatic skarn and alkali rich intrusion couple”. (5) It develops sideronitic texture, bean structure, flow structure and vesicular structure. (6) Its characteristics of trace elements and REE are similar to those of related igneous rock. (7) The melting inclusions have been discovered and homogenization temperatures up to above 1 000℃. (8) No distinguished difference can be found between magmatic skarn and contact metasomatic skarn in mineral assemblages and chemical composition. The authors of this paper that magmatic skarn is the product of the evolution intermediate acidic magma in depth.
出处
《长春科技大学学报》
CSCD
1998年第4期366-372,共7页
Journal of Changchun University of Science and Technology
基金
国家自然科学基金
