淮北袁店8煤岩浆热蚀变的微组构响应

Microfabrics response of coal to magma among coal seam Ⅷ in Yuandian Mine of Huaibei City,China

选取袁店8煤层内碎裂煤、焦油煤、天然焦和火夹焦为研究对象,研究其显微图像和拉曼光谱特征,揭示不同变质程度煤微组构特征及其对岩浆蚀变的响应。结果显示,碎裂煤以均质镜质体为主,微裂隙网脉发育,ID=3 500~7 300,IG=5 000~12 000;焦油煤由碎裂镜质体和少量煤焦油组构,ID和IG均介于1 000~3 500;天然焦由碳质中间相及其内部所包裹的气泡和焦油液滴组成,ID=430~700,IG=380~650;火夹焦由焦化基质及较小气泡和少量矿物微球组成,ID=920~1 560,IG=640~910。分析显示,趋近岩体,碳质组分由干燥破裂、挤压破碎向中间相和熔融态转变;碳质组分拉曼光谱IG/ID值逐渐降低。这表明,趋近岩体,煤层遭受破坏和变质程度逐渐增强,煤分子片层持续解聚,层间缺陷不断增加,碳质组分的结构有序度逐渐降低。

Some samples of cataclastic coal,zetar coal,cokeite and Magma coke were retrieved from coal seam Ⅷ to characterize the signature of microscopic image and Raman spectroscopy for reshaping the microfabrics response of coal to magma in Yuandian Mine.The results show several points as follows：a） the values of ID range from 3 500 to 7 300 and the range of IG are from 5 000 to 12 000 in cataclastic coals which are composed of telocollinite and microcracks vein;b） the values of ID and IG are both between 1 000 and 3 500 in zetar coal which are consist of corpovitrinite and zetar;c） the values of ID range from 430 to 700 and the range of IG are from 380 to 650 in cokeite which are made up of carbonaceous,bubbles and zetar droplet;d） the values of ID are 920-1 560 while the values of IG are 640-910 in magma coke,which are formed with coking substrate,small bubbles and mineral spheres.Consequences above display that the metamorphisms tend to magma transform from rupture and broken in cataclastic coal and zetar coal to soften and molten in cokeite and magma coke.It indicates that the intensity of alteration in coal and defects in coal molecules increase rapidly.