鸡西盆地张新地区浅成侵入体对围岩有机质成熟度及变质程度的影响  

Effects of organic matter maturity and metamorphic grade from surrounding rocks by hypabyssal intrusion in Zhangxin area of Jixi Basin

作　　者：朱占平[1] 刘立[1] 马瑞[1] 宋土顺[1] 邱增凯[2] 

机构地区：[1]吉林大学地球科学学院,长春130061 [2]吉林大学仪器科学与电气工程学院,长春130061

出　　处：《世界地质》2012年第2期345-350,共6页World Geology

基　　金：国家油气专项(XQ-2004-07);吉林大学业务费项目(450060323024)联合资助

摘　　要：利用鸡西盆地张新地区西风井揭示的连续剖面,采用镜质体反射率、伊利石结晶度分析测试方法对西风井浅成岩侵入后的上盘围岩有机质成熟度(Ro)、变质程度进行研究,发现上盘围岩的镜质体反射率随远离辉绿玢岩体的距离增加而减少(由2.31%到0.79%);侵入体对上盘围岩有机质影响最大距离为129.06 m,是岩体厚度的1.2倍;伊利石结晶度数据显示围岩处于极低级变质程度,围岩的温度随远离辉绿玢岩体的距离增加而降低;计算得出西风井城子河组地层最大埋藏温度为259.24℃,持续时间117.7 a。最高温度及其持续时间决定围岩的变质程度,是围岩接触变质程度较低的原因。Using the serial profile revealed by Xifeng well in Zhangxin area of Jixi Basin, the authors study the organic matter maturity （Ro） and metamorphic grade of hanging wall surrounding rocks from hypabyssal intrusion by vitrinite reflectance and illite crystallinity testing. The results show that vitrinite reflectance of hanging wall surrounding rocks decreases with the increasing of distance between the sillite and the surrounding rocks （from 2. 31% to 0. 79% ）. The largest distance of the effect from intrusion to organic matteris of hanging wall surrounding rocks is 129.06 m, which is 1.2 times of rock thickness. The illite crystallinity data indicate that the surrounding rocks are in very low metamorphic grade, and the temperature of surrounding rocks decreases with the increasing of distance between the sillite and the surrounding rocks. The highest buried temperature of Chengzihe Formation at Xifeng well is 259.24 ℃, lasting 117.7 years. The highest temperature and duration time can determine the metamorphic grade of surrounding rocks, which are the cause of low contact metamorphic grade of surrounding rocks.

关 键 词：鸡西盆地 浅成岩 变质程度 镜质体反射率 影响 

分 类 号：P614[天文地球—矿床学]