【作者】 刘敬党；

【导师】 肖荣阁；

【作者基本信息】 中国地质大学（北京） ， 矿物学、岩石学、矿床学， 2006， 博士

【摘要】 硼酸盐型硼矿是我国重要矿产资源,其矿产品硼酸及硼砂广泛应用于化工业、冶金业、国防航天工业、原子能工业、医药业及光学玻璃、橡胶、建材等轻工建筑业。目前我国可以利用的硼酸盐型硼矿资源主要是辽东地区的硼镁石型硼矿(俗称白硼)和青藏高原的盐湖卤水硼砂矿。由于青藏高原盐湖硼矿地处边远地区,自然条件恶劣,交通不便,目前产量不足国内需求量的8%,而辽东地区硼矿满足了我国硼矿国内需求的92%。由于国内经济发展对硼矿需求急剧增加,硼矿资源消耗加速,硼矿资源储量日渐紧张,已经面临危机,不能满足国内经济增长需求。为了缓解硼矿资源紧张局面,保障国民经济的可持续发展,需大力开展硼矿资源调查工作,寻找后备资源基地,缓解我囯硼矿资源紧缺局面.本研究课题的目的是对辽东硼矿区矿床成因进行研究,对硼矿资源前景进行分析评价,从而对硼矿资源勘查提供理论依据。⑴通过含硼岩系岩石学研究,认为含硼岩系沉积环境属于局限裂谷环境,提出其中主要含硼岩石高镁岩石镁橄榄岩属于超基性喷出岩-科马提岩的认识。⑵提出层状混合岩作为含硼岩系的一个岩组,认为是含硼岩系经过区域混合岩化的结果,提出混合岩化强度与原岩岩性有关的认识。⑶研究硼矿成矿作用,建立了辽东地区硼矿成矿模型,认为硼矿成矿主要经历了两个阶段,即原始富集阶段与部分熔融混合岩化成矿阶段。指出了成矿的主要控制因素是成矿物质原始富集、镁质基岩的形成、部分熔融作用的出现。归纳硼矿床的成矿模式为部分熔融成矿模式:硼元素初始富集+镁质岩石形成→混合岩化形成硼酸热液→交代镁质岩石形成镁硼酸盐矿物或交代铝质岩石形成硼硅酸盐矿物电气石。⑷分析了辽东地区硼矿的控矿模型与找矿模型,即层状混合岩控矿模型与滑动推覆构造的控矿模型。指出了主要的找矿标志是含硼岩系及超镁质岩石的存在,与混合岩化作用的存在。⑸在上述研究基础上根据找矿勘查实践,取得了大石桥地区、宽甸砖庙地区、宽甸杨木杆地区硼矿找矿的重大突破,尤其是在营口地区花岗岩下部找到大型硼矿,根据混合花岗岩是含硼岩系的顶部岩组这一认识,我们首开鲁家沟地段混合花岗岩深部找矿工作,连续在混合花岗岩覆盖区的鲁家沟、东岔沟、二道沟深部、鲁家南沟地段和板长峪发现深部隐伏硼矿床,已经提交B2O3硼矿储量25万吨。现正在勘查的鲁家南沟矿段已经控制硼矿长125米(现在坑道还未穿透矿体),宽70余米,厚度大于50米,品位15.62%—26.79%。该矿品位高、厚度大,有望达到大型硼矿床;大石桥市板长峪矿段,见到了厚度68.85米,平均品位14.40%的矿体,这是迄今为止在辽东地区见到的巨厚硼镁石型矿体,有望在板长峪地段找到中型至大型硼镁石型矿床。更多还原

【Abstract】 Borate Depoists are one vital kind of mineral resources in China. Its mineral products likeboric acid and borax are extensively used in chemical industry, metallurgy, aviatic industry,atomic energy industry, medicine, optical glass, rubber and construction materials, etc. So far in China the workable borate resources are szaibelyite-type borate deposits (so-called“white borate”) in east Liaoning and brine borax in salines in Qinghai-Tibet Platean. Due to itspoor infrastructures in outlying areas, brine borax is mined at a limited capacity, less than 8% ofinternal market need, while borate deposits in east Liaoning offer 92%. The rapid-developing economy has a surging demand for borate minerals, which resulted ina shortage in borate reserve. In order to mitigate the shortage in borate resource and to ensure thesustainable development of economy, it is necessary to survey and explore more borate minerals.This dissertation studied the genesis of borate deposits in east Liaoning, assessed the boratepotential and then supplied a theoretical guide for surveying and exploring borate minerals.(1) Study on petrology reveals that boron-bearing sequences are formed under a limited riftenvironment and that boron-bearing Mg-peridotite originated from komatiite, a kind ofultrabasic effusive rocks.(2) Laminated migmatite as a boron-bearing formation is a consequence of regionalmigmatitization with magmatitization strength related to lithology of original rocks.(3) A mineralized model of borate deposits, established for east Liaoning based on boratemineralization, indicates that borate mineralization underwent two processes, first primaryenrichment and then partial melting migmatitization. The major mineralization factorsinclude primary enrichment of element boron, formation of Mg-bearing bedrock and partialmelting. Partial melting model can be simplified as follows: primary enrichment of elementboron & formation of Mg-bearing ultrabasic rocks → boron-bearing acid hydrotherm bymigmatizitization → Mg-bearing borate minerals via replacing Mg-bearing ultrabasic rocksor boron-bearing silicate minerals via replacing Al-bearing ultrabasic rocks.(4) A mineralization model, established for borate deposits in east Liaoning, can besummarized as laminated migmatite model and slide thrust structure model. A surveymodel shows that the chief survey indexes are marked by boron-bearing sequences,Mg-bearing ultrabasic rocks and migmatitization.(5) According to the theory above and survey practice, economic borate ore bodies werediscovered in Dashiqiao, Zhuanmiao (Kuandian County) and Yangmugan (KuandianCounty) areas, especially large-sized ore bodies were explored beneath granites in Yingkouarea, an important breakthrough;hence, migmatized granites are viewed as the topformation of boron-bearing sequences. Hidden ore bodies were explored in Lujiagou,Dongchagou, Erdaogou, Lujianangou and Banchangyu blocks where the surface is coveredwith migmatized granites, acquiring 250 kt of B2O3. Exploration work presently in Lujianangou block has conformed that borate ore bodies are125m long (not opened), 70m wide and 50m thick at a grade of B2O3 15.62-26.79%. It could bemost possibly a large borate deposit. The thickest szaibelyite body was explored in Banchangyublock, Dashiqiao County, 68.85m thick at a mean grade of B2O3 14.40%, a potential medium tolarge-sized szaibelyite deposit.更多还原