鸡西煤田的煤化作用模式

COALIFICATION PATTERN OF JIXI COALFIELD

鸡西煤田由于多数地区受到异常古热流的影响，常存在两种或两种以上类型的变质作用相互叠加，从而导致各区的煤化作用模式各不相同，比较复杂。根据鸡西煤田北部条带各区煤变质作用的控制因素和演化特征，结合构造和沉积演化史，对比较典型的煤化作用模式进行了分析。深成变质可以划分为持续沉积变质阶段、回返褶皱继续变质阶段和回返期后继续（停止）变质阶段，具有长期性发展和阶段性变化的特点；根据岩浆侵入深度，区域岩浆热变质可划分为浅成岩浆热变质和中深成岩浆热变质，前者煤变质带分布主要与岩浆热液通道相关，后者主要受煤层与岩体之间的距离影响，深成变质奠定了鸡西煤变质的基础，而区域岩浆热变质是煤田形成大部分中、高变质程度烟煤的主要原因。

Most areas of Jixi Coalfield were affected by the anomalous paleothermal flow. One or more types of metamorphism were superposed by the geothermal metamorphism, which led to different and complicated coalification patterns in Jixi Coalfield. Based on the control factors, evolution characteristics of metamorphism in the northern belt by taking into consideration of tectonics and sedimentary history, the typical coalification patterns are discussed. The hypometamorphism can be invided into persistent depositional metamorphism stage, inversion folding metamorphism stage and post-inversion folding metamorphism stage (or stop metamorphism stage). It is of long-term development and periodic change characteristics. In terms of the depth of the magmatic intrusion, the telemagmatic thermal metamorphism can be divided into hypabyssal and mesozone magmatic metamorphism. The former is related to the pathway of magmatic hydrothermal solution and the latter is related to the distance between the coal measures and the magmatic body. The hypometamorphism brought about the normal coal metamorphism and the telemagmatic thermal metamorphism is the main factor for forming the most medium and high rank bituminous coal.