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湘西花垣铅锌矿床是一个产于下寒武统清虚洞组碳酸盐岩中的大型ＭＶＴ铅锌矿床，含矿岩系为大陆边缘相的藻灰岩、鲕粒灰岩夹黑色泥质条带灰岩。矿区及外围的寒武系中有大量沥青出现。矿区的沥青以细粒状、鳞片状充填于矿石的晶间孔隙或裂缝中，与闪锌矿、方铅矿共生。外围沥青多充填于石英重晶石脉的晶洞中或断裂带中。根据沥青的Ｒｏｍａｘ，Ｈ／Ｃ（原子比），Ｔｍａｘ℃，ＰｙＧｃ，δ１２Ｃ，ＲＥＥ和微量元素测定，矿区的沥青的热演化程度较高（Ｒｏｍａｘ＝４．３２％－４．７０％；，Ｈ／Ｃ（原子比）＝０．５，Ｔｍａｘ＝４０６－６００℃），属脆沥青－２阶段，其演化程度与矿床的成矿温度相吻合（均一温度范围：８０～２００℃，均值１３５－１５１℃）。沥青的类型属原生－同层型，有机质来源可能与主岩有关，并参与成矿作用。
The Huayuan Pb-Zn deposit in western Hunan is a large-scale MVT lead-zinc deposit produced in carbonate rocks of the Lower Cambrian Qingxuendong Formation. The ore-bearing rocks are algal limestone with continental margins and black oolitic limestone with black argillaceous strata Limestone. A large amount of bitumen appears in the Cambrian and outer Cambrian areas. The bitumen in the mining area is finely grained and scaly filled in intergranular pores or fissures of the ore and coexists with sphalerite and galena. Peripheral bitumen is more filled in the crystal caves of the quartz-barite vein or in the fault zone. According to the Romax, H / C (atomic ratio), Tmax ° C, PyGc, δ12C, REE and trace elements, the thermal evolution of bitumen in the mining area is higher (Romax = 4.32% -4.70% , H / C (atomic ratio) = 0.5, Tmax = 406-600 ℃), which belongs to Brittle Asphalt-2 stage and its evolution degree coincides with the metallogenic temperature of the ore bed (homogenization temperature range 80 ~ 200 ℃, 135-151 ° C). The type of bitumen is of primary-stratigraphic type. The source of organic matter may be related to the host rock and participate in the mineralization.