【摘要】：研究區(qū)地處四川盆地東緣的大巴山東段南麓,構(gòu)造單元主要隸屬上揚(yáng)子陸塊米倉山-大巴山基底逆推帶中的巫溪凹褶束。區(qū)內(nèi)發(fā)現(xiàn)有多處砂巖型銅礦點(diǎn)及礦化點(diǎn),含礦地層為三疊系中統(tǒng)巴東組,巴東組呈近東西向分布于塘坊-菱角及竹園-上磺一帶。本文根據(jù)野外調(diào)查及實(shí)測(cè)地層剖面資料,通過對(duì)巴東組巖石特征、沉積構(gòu)造及沉積環(huán)境的研究進(jìn)行了地層劃分對(duì)比及沉積相分析;同時(shí),對(duì)產(chǎn)于巴東組二段內(nèi)的銅礦(化)體特征、成礦地質(zhì)條件和礦化成因進(jìn)行了分析討論,取得了以下幾點(diǎn)認(rèn)識(shí):1、巴東組巖性以紫紅色夾灰綠色中-薄層泥巖、鈣質(zhì)泥巖、粉砂質(zhì)泥巖、泥質(zhì)粉砂巖為主夾淺灰色泥灰?guī)r,中部夾有灰色薄-中厚層狀泥質(zhì)灰?guī)r、白云質(zhì)灰?guī)r、白云巖、泥灰?guī)r及鈣質(zhì)頁巖。巴東組沉積環(huán)境總體上屬于障壁海岸相,根據(jù)其巖性組合特征可細(xì)分為四個(gè)巖性段。2、巴東組一段為泥巖、粉砂質(zhì)泥巖、鈣質(zhì)泥巖的巖石組合,屬障壁海岸相碎屑潮坪環(huán)境沉積。巴東組二段主要為紫紅色厚層-塊狀含鈣質(zhì)結(jié)核粉砂質(zhì)泥巖、紫紅色中-薄層狀粉砂質(zhì)泥巖、鈣質(zhì)泥巖夾灰綠色中層細(xì)砂巖,屬障壁海岸島的碎屑潮坪相沉積。巴東組三段基本層序?yàn)?微晶灰?guī)r→泥灰?guī)r→鈣質(zhì)泥巖、白云巖→生物碎屑灰?guī)r,屬碳酸鹽潮坪環(huán)境沉積。巴東組四段基本層序?yàn)殁}質(zhì)泥巖→白微晶白云巖,屬瀉湖亞相沉積。3、研究區(qū)發(fā)現(xiàn)的6處銅礦點(diǎn)或礦化點(diǎn),其構(gòu)造部位處于青龍包-菱角向斜的南翼或寨包-長梁子近東西向背斜構(gòu)造的南翼,含礦地層均為三疊系巴東組二段,銅礦化層發(fā)育于此套地層中的灰綠色細(xì)砂巖、粉砂巖或泥質(zhì)粉砂巖夾層中,礦化體呈似層狀、不規(guī)則脈狀、透鏡狀、雞窩狀順層斷續(xù)產(chǎn)出。礦化以銅為主,伴有銀、鉬等的富集。礦體厚0.35~4.10m,銅品位一般在0.94~5.08%之間;Ag含量主要在(2.5-7.9)×10-6之間,最高可達(dá)6500×10-6。Mo含量在(0.32-1.8)×10-6,最高可達(dá)400×10-6。礦石礦物呈薄膜狀、細(xì)脈狀沿裂隙斷續(xù)分布。礦石自然類型有:①淺灰綠色細(xì)粒砂巖型銅礦石,礦物成分主要為孔雀石,少量輝銅礦;②灰-綠色泥質(zhì)粉砂巖型銅礦石,礦物成分主要為為孔雀石,少量銅蘭、輝銅礦及藍(lán)銅礦;③淺灰色-翠綠色粉砂巖型銅礦石,主要礦物成分為孔雀石,次為銅蘭、輝銅礦、斑銅礦、黝銅礦及黃銅礦。礦石中金屬礦物成分分布不均勻,脈石礦物主要為石英、長石、方解石等。巴東組二段砂巖型銅礦,其富集的主要控制因素是地層和沉積環(huán)境,具有明顯的層位特征;其次則與巖石性質(zhì)及所發(fā)育的構(gòu)造裂隙有關(guān)。具體表現(xiàn)在“灰綠色粉-細(xì)砂巖層”的厚度、范圍、有機(jī)質(zhì)含量及其構(gòu)造裂隙的發(fā)育程度,是較為典型的層控型-熱液疊加改造型銅礦。
[Abstract]:The study area is located at the southern foot of Daba Shandong section in the eastern margin of Sichuan Basin, and the tectonic unit is mainly belong to the Wuxi fold in the basement inversion belt of the upper Yangtze block. There are many sandstone-type copper deposits and mineralization sites in the area. The ore-bearing strata are the Padong formation of the Middle Triassic, and the Badong formation is distributed in the near east-west direction in the areas of Tangfang-Lingjiao and Zhuyuan-Shangmeng. Based on field investigation and measured stratigraphic profile data, stratigraphic division and correlation and sedimentary facies analysis are carried out on the basis of the study of the rock characteristics, sedimentary structure and sedimentary environment of Badong formation. At the same time, the characteristics, ore-forming geological conditions and mineralization genesis of copper ore bodies in the second member of the Badong formation are analyzed and discussed. The results are as follows: 1. The lithology of the Badong formation is grayish green and grayish green. Calcareous mudstone, silty mudstone, shaly siltstone are mainly intercalated with light gray marl, and in the middle there are gray thin-medium thick layer marlite, dolomite, marlite and calcareous shale. The sedimentary environment of Badong formation is generally a barrier coastal facies, which can be subdivided into four lithologic segments according to its lithologic assemblage. 2. The first member of Badong formation is composed of mudstone, silty mudstone and calcareous mudstone. It belongs to barrier coastal clastic tidal flat environment. The second member of Badong formation is mainly composed of fuchsia thick layer and massive calcareous nodule silty mudstone, purplish red medium-thin layer silty mudstone, calcareous mudstone intercalated with gray-green meso-fine sandstone, which belongs to clastic tidal flat facies deposit of barrier coast island. The basic sequence of the third member of Badong formation is: microcrystalline limestone, mudstone, calcareous mudstone, dolomite and bioclastic limestone, which belong to carbonate tidal flat environment. The basic sequence of the fourth member of the Badong formation is calcareous mudstone albinite microcrystalline dolomite, which belongs to lagoon subfacies deposition. Its structural position is located in the southern wing of Azure Dragon Bao-Diamond syncline or the southern wing of Zaibao-Changliangzi structure near the east-west anticline. The ore-bearing strata are all the second member of the Padong formation of the Triassic system. The copper mineralization strata are developed in the grey-green fine sandstone in this set of strata. In siltstone or argillaceous siltstone intercalation, the mineralized bodies are stratiform, irregular veins, lenticular and chicken nest. The mineralization is mainly copper, accompanied by the enrichment of silver and molybdenum. The ore body thickness is 0.35 ~ 4.10 m, and the copper grade is generally between 0.94 and 5.08%. The content of Ag is mainly between (2.5-7.9) 脳 10 ~ (-6), the highest content is 6500 脳 10-6.Mo (0.32-1.8) 脳 10 ~ (-6), and the highest is 400 脳 10 ~ (-6). The ore minerals are thin-film and veined along the fissures. The natural types of ore are as follows: 1 the mineral composition is mainly malachite and a small amount of chalcopyrite; (2) Grey-green argillaceous siltstone type copper ore, the mineral composition is mainly malachite, a small amount of copper blue, chalcopyrite and blue copper ore; The main mineral composition is malachite, followed by copper blue, chalcopyrite, pyrite, tetrahedrite and chalcopyrite. The distribution of metallic minerals in ores is uneven, and the gangue minerals are mainly quartz, feldspar, calcite and so on. The sandstone-type copper deposits in the second member of the Badong formation are mainly controlled by stratigraphic and sedimentary environments and have obvious stratigraphic characteristics, followed by lithologic properties and tectonic fractures developed in the second member of the Badong formation. The thickness, range, content of organic matter and the degree of development of structural fissures of "grey-green silt-fine sand strata" are typical strata-controlled and hydrothermal superimposed and reformed copper deposits.
【學(xué)位授予單位】：成都理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：P618.41

【參考文獻(xiàn)】

相關(guān)期刊論文 前7條

1 高春華;張鵬暉;;淺論渝東奉節(jié)一帶巴東組砂巖型銅礦特征及富集規(guī)律[J];中國城市經(jīng)濟(jì);2010年09期

2 蔣德和，，楊振強(qiáng)，趙時(shí)久;湘中地區(qū)中奧陶統(tǒng)沉積巖的稀土元素地球化學(xué)[J];沉積學(xué)報(bào);1994年01期

3 武紅嶺;施煒;董樹文;田蜜;;大巴山前陸疊加構(gòu)造力學(xué)特征的模擬研究[J];地學(xué)前緣;2009年03期

4 劉恩法;李書文;劉向陽;;砂巖型銅礦成礦機(jī)制分析[J];價(jià)值工程;2014年31期

5 吳小慶;趙路子;黃亮;丁熊;唐青松;;川中-川南過渡帶雷口坡組沉積相特征[J];四川地質(zhì)學(xué)報(bào);2010年03期

6 王二七;尹紀(jì)云;;川西南新生代構(gòu)造作用以及四川原型盆地的破壞[J];西北大學(xué)學(xué)報(bào)(自然科學(xué)版);2009年03期

7 韓潤生;鄒�？�;劉叢強(qiáng);馬更生;;中國云南易門式銅礦床的主要類型及成因(英文)[J];地質(zhì)通報(bào);2007年12期

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