湘西北叶溪育含钒石煤矿地质特征及稀土元素分析

Vanadium Contained Stone-like Coal Geological Characteristics and REE Analysis in Yexiyu,Northwestern Hunan

叶溪育石煤是湖南省境内一种比较特殊的煤种,其赋矿层位属"下寒武统黑色含矿岩系",主要分布于寒武系下统小烟溪组下段,一般含石煤层3层,个别地段为4-5层。叶溪育石煤矿可采石煤主要为第二层,厚度4.98～9.18m,平均7.49m。该矿石煤分布面积大,层位稳定,连续性较好;原煤发热量3.52～10.23MJ/kg,灰分产率52.12%～74.32%,全硫平均含量1.56%,为中硫、高灰分、低发热量的劣质煤;煤系地层中同时含钒矿体Z1、Z2、Z3,呈似层状、透镜状产出,其中Z1矿体已达中型规模;根据稀土元素地球化学分析,含煤岩系形成于缺氧的还原环境,矿床成因属于生物地球化学沉积矿床。

The Yexiyu stone-like coal is a kind of rather peculiar coal type in the Hunan Province.Its hosting horizon belongs to ＂ Lower Cambrian black mineral containing rock series＂,mainly distributed in Lower Member,Xiaoyanxi Formation,Lower Series,Cambrian System,generally contains 3 stone-like coal seams,in several areas 4~5 seams.Main mineable stone-like coal seam in the Yexiyu stone-like coalmine is the No.2 coal seam,with thickness 4.98~9.18m,average 7.49m.Stone-like coal in the mine has large distribution area,coal seam stable,rather good continuity.Raw coal calorific value is 3.52~10.23MJ/Kg,ash content 52.12%~74.32%,average total sulfur content 1.56%,thus a medium sulfur,high ash,low calorific value inferior coal.In the coal measures contain vanadium ore-bodies Z1,Z2 and Z3 simultaneously,stratoid structure,lenticular occurrence,in which,Z1 ore-body comes to medium sized scale.Based on REE geochemical analysis,coal-bearing strata were formed in an anoxic reduction environment;belong to biogeochemical sedimentary mineral deposit.