【摘要】：龍灣礦床位于佛子沖礦田南部,佛子沖礦田坐落于桂東南岑溪市北東約50Km與蒼梧縣的交界處,是我國(guó)華南地區(qū)重要的大型鉛鋅多金屬礦田之一。本論文通過(guò)研究礦床地質(zhì)特征,控礦因素,并結(jié)合地、物、化信息特征,運(yùn)用GIS的空間分析功能進(jìn)行了綜合信息成礦預(yù)測(cè),并圈定了靶區(qū)。通過(guò)研究主要取得以下認(rèn)識(shí)：(1)通過(guò)光薄片鑒定和野外的詳細(xì)調(diào)查,廣西佛子沖龍灣礦床礦體主要賦存于奧陶系中統(tǒng)上組上段(O2b-2)層位中,圍巖蝕變具有典型的巖漿熱液蝕變的特點(diǎn)。根據(jù)礦石組構(gòu)特征,以及礦物之間的穿插關(guān)系的研究,礦石具以下組構(gòu)特怔：結(jié)構(gòu)(交代結(jié)構(gòu)和結(jié)晶結(jié)構(gòu)),構(gòu)造(塊狀構(gòu)造、脈狀構(gòu)造和浸染狀構(gòu)造),由于該礦區(qū)巖漿活動(dòng)、構(gòu)造運(yùn)動(dòng)十分強(qiáng)烈,使得礦化具有多期性,礦物之間的交代作用十分普遍,類型繁多,多期多階段是該礦床成礦的重要特點(diǎn)。(2)根據(jù)礦床地質(zhì)和地層、巖體含礦性并結(jié)合礦床成礦物質(zhì)來(lái)源的研究可以認(rèn)為：佛子沖礦田龍灣鉛鋅礦床的成礦時(shí)間與燕山晚期花崗斑巖形成同期(或稍晚),其成礦物質(zhì)一部分來(lái)源于奧陶系中統(tǒng)上組上段(O2b-2)和上統(tǒng)上組上段(O3b-2),一部分來(lái)自于燕山晚期巖漿攜帶的含礦物質(zhì)。礦床的形成有兩期。第一期為成巖成礦期,形成了奧陶系中統(tǒng)上組上段(O2b-2)和上統(tǒng)上組上段(O3b-2)地層為初始礦源層。礦床內(nèi)奧陶系中統(tǒng)上組上段(O2b-2)和上統(tǒng)上組上段(O3b-2)鉛鋅元素含量大大高于中國(guó)陸殼元素豐度值,為后期的成礦提供了豐富的物質(zhì)來(lái)源和良好的背景。第二期為燕山晚期巖漿侵入的疊加改造期。對(duì)地球化學(xué)同位素方面的研究,S同位素具有隕石硫的特征,與巖漿活動(dòng)密切相關(guān),因此,可以認(rèn)為佛子沖礦田龍灣鉛鋅礦床成因應(yīng)該為早期奧陶系沉積(形成初始礦源層)+燕山晚期巖漿熱液疊加改造。(3)通過(guò)對(duì)該礦區(qū)礦床地質(zhì)特征和控礦條件分析,認(rèn)為該礦床是由地層巖性(泥質(zhì)灰?guī)r、鈣泥質(zhì)粉砂巖)、NNE構(gòu)造破碎帶和花崗斑巖三位一體聯(lián)合控制。(4)通過(guò)對(duì)該區(qū)的地、物、化多源地學(xué)信息特征進(jìn)行了分析,總結(jié)并建立了廣西龍灣礦床的綜合信息找礦模型。通過(guò)對(duì)礦區(qū)運(yùn)用GIS的空間分析功能進(jìn)行了綜合信息成礦預(yù)測(cè),圈定了找礦靶區(qū)8個(gè)：3個(gè)Ⅰ級(jí)靶區(qū)、2個(gè)Ⅱ級(jí)靶區(qū)、3個(gè)Ⅲ級(jí)靶區(qū)。
[Abstract]:Longwan deposit is located in the south of Fuzichong Orefield, which is located at the junction of 50Km and Cangwu County in the north east of Cenxi City, southeast of Guangxi. It is one of the important large Pb-Zn polymetallic fields in South China. By studying the geological characteristics of ore deposits, ore-controlling factors, and combining the characteristics of ground, material and chemical information, the paper makes use of the spatial analysis function of GIS to carry out the comprehensive information metallogenic prediction and delineates the target area. The main results are as follows: (1) through the identification of light sheet and the detailed investigation in the field, the orebody of Longwan deposit in Fucinchong, Guangxi is mainly located in the upper member of Upper Ordovician formation (O2b-2). The wall rock alteration is characterized by typical magmatic hydrothermal alteration. According to the characteristics of ore fabric and the intercalation relationship between minerals, the ore is characterized by the following structures: structure (metasomatic structure and crystalline structure), structure (block structure, vein structure and disseminated structure), As a result of magmatic activity and strong tectonic movement in this mine, mineralization is of multi-period nature, and the metasomatism between minerals is very common, and there are many types of metasomatism. Multi-period and multi-stage are the important characteristics of mineralization of the deposit. (2) according to the geological and stratigraphic characteristics of the deposit, The ore-forming time of Longwan Pb-Zn deposit in Fuzichong Orefield and the late Yanshanian granitic porphyry formed at the same time (or later) can be considered. Some of the ore-forming materials are derived from the upper member of Upper Ordovician formation (O2b-2) and the Upper member of Upper Ordovician formation (O3b-2), and partly from the ore-bearing materials carried by magma in the late Yanshanian period. There are two stages in the formation of the deposit. The first stage is the diagenetic and metallogenic period, forming the upper member of Upper Ordovician Upper formation (O2b-2) and Upper member of Upper Ordovician formation (O3b-2), which is the initial source bed. The contents of lead and zinc elements in upper member (O2b-2) and upper member (O3b-2) of Ordovician are much higher than the abundance of continental crust elements in China, which provides abundant material source and good background for late mineralization. The second stage is the stage of superposition and transformation of late Yanshanian magma intrusion. In the study of geochemical isotopes, S isotopes have the characteristics of meteorite sulfur and are closely related to magmatic activity. It can be concluded that the origin of the Longwan Pb-Zn deposit in Faozichong Orefield should be superimposed by magmatic hydrothermal superposition in the late Yanshanian period of early Ordovician sedimentation (formation of initial source bed). (3) by analyzing the geological characteristics and ore-controlling conditions of the deposit, It is considered that the deposit is controlled jointly by stratigraphic lithology (argillaceous limestone, calcareous siltstone), NNE structural fracture zone and granitic porphyry). The comprehensive information prospecting model of Longwan deposit in Guangxi is summarized and established. By using the spatial analysis function of GIS, this paper makes a comprehensive information metallogenic prediction, and delineates 8 ore prospecting targets: 3 鈪，

本文編號(hào)：2422380