(1. 中南大學(xué) 有色金屬成礦預(yù)測(cè)教育部重點(diǎn)實(shí)驗(yàn)室，長(zhǎng)沙 410083；
2. 中南大學(xué) 地球科學(xué)與信息物理學(xué)院，長(zhǎng)沙 410083)
摘 要: 為了研究大河邊重晶石礦床中有機(jī)質(zhì)來(lái)源和沉積環(huán)境，對(duì)重晶石礦石及圍巖進(jìn)行有機(jī)碳、硫、氯仿瀝青“A”及其族組成和飽和烴氣相色譜-質(zhì)譜等測(cè)試分析，并對(duì)有機(jī)質(zhì)豐度和成熟度等有機(jī)地球化學(xué)特征進(jìn)行研究。結(jié)果表明：重晶石礦石和圍巖中有機(jī)質(zhì)含量和成熟度均較高，表明其經(jīng)歷了類似的地質(zhì)作用過(guò)程；生物標(biāo)志物指標(biāo)和圖解表明有機(jī)質(zhì)來(lái)源以海洋細(xì)菌和藻類等低等生物為主，有機(jī)質(zhì)形成于強(qiáng)還原和高鹽度的沉積環(huán)境。高鹽度和碳分布等特征表明有熱液參與成礦，礦床鹽度分布特征表明海底熱液噴口在豬圈灣和大河邊附近。
關(guān)鍵字: 有機(jī)地球化學(xué)；大河邊重晶石礦床；沉積環(huán)境
（1. Key Laboratory of Metallogenic Prediction of Nonferrous Metals, Ministry of Education,
Central South University, Changsha 410083, China;
2. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China）
Abstract:To research the organic matter sources and sedimentary environment in Dahebian barite deposit, barite ore and wall rock were used for the analyses of organic carbon, sulfur, chloroform bitumen “A” and their group composition and saturated hydrocarbons detected by gas chromatography, and the organic geochemistry characteristics involving the organic matter abundance and maturity were discussed. The results show that both the content and grade of maturity of the organic matter are high in barite ore and host rock, which makes it clear that the barite ore and host rock experience similar geological processes. Biomarkers indices and diagrams show that the organic matter is mainly sourced from lower organisms such as marine bacteria and algae, and formed in a sedimentary environment of high reduction and high salinity. The distribution characteristics of high salinity and organic carbon in barite ore and host rock show that hydrotherm is involved in metallogenesis, while the distribution characteristic of the high salinity indicates that the undersea hydrothermal vents exist near Zhujuanwan and Dahebian in Tianzhu County.
Key words: organic geochemical; Dahebian barite deposit; sedimentary environment
