陆表海盆地不同海侵背景下黏土岩特征及其应用价值——以枣庄陶枣煤田为例

Features and Application Value of Epicontinental Sea Basin Claystone under Different Transgression Settings——A Case Study of Taozao Coalfield,Zaozhuang

采用煤地质学、煤地球化学及沉积学方法,对枣庄陶枣煤田早二叠纪13、14和17煤层及底板黏土岩进行采样测试发现:不同煤层底板的黏土岩质量存在着差异,13、14煤为海退形成煤层,其黏土岩高岭石、伊利石含量相对较低,石英含量较高,形态多呈尖棱状。17煤是海侵形成,其黏土岩高岭石、伊利石含量相较高,石英含量较低,形态多为次圆状,化学风化指数(CIA)在84.26%~92.18%,平均为88.22%,受到的化学风化作用较弱,黏土质量更好;化学分析结果表明:研究区黏土岩SiO_2含量为40.61%~63.91%,Al_2O_3含量为21.52%~42.92%,碱金属及其他氧化物含量较低,且Fe_2O_3含量为0.48%~2.98%,TiO_2含量为0.31%~1.32%,在耐火材料工业达到一级品位,有利于深加工应用。该研究结果为煤系共伴生矿产开采提供了一定的依据。

Using coal geological, coal geochemical and sedimentological methods have carried out sampling and testing for early Permian coal Nos. 13, 14, 17 and floor claystone in the Taozao coalfield, Zaozhuang.. The result has shown that the quality of floor claystnne under different coal seams is different. Coal Nos. 13 and 14 were formed during regression, the claystone has relatively lower kaolinite and illite contents, higher quartz content, mostly sharp angular in shape. Coal No. 17 was formed during transgression, the claystone has relatively higher kaolinite and illite contents, lower quartz content, mostly subrounded in shape; the chemical weathering index （ CIA ） is between 84. 26% -92. 18%, average 88.22%, thus weaker chemical weathering, claystone quality is better. The chemical analyzed results have shown that study area claystone SiO2 content range between 40. 61% - 63.91%, AlO3 between 21.52% 42. 92% ; contents of alkali metals and other oxides are rather low, Fe2O3 between 0.48% -2. 98%, TiO2 between 0. 31% - 1.32% , thus the grade I in refractory industry, conducive to deep processing applications. The result has provided certain basis in coal meas- ures coexisting and associated minerals exploitation.