哀牢山結(jié)合帶北段侵入巖地球化學(xué)特征及地質(zhì)意義
發(fā)布時(shí)間：2018-11-27 11:31
【摘要】：哀牢山結(jié)合帶呈北西—南東向展布,其先后經(jīng)歷了晚古生代—早中生代的特提斯演化,新生代印度板塊—?dú)W亞板塊碰撞,為一條重要的構(gòu)造轉(zhuǎn)換響應(yīng)帶。在研究區(qū)哀牢山結(jié)合帶被三條區(qū)域性深大斷裂所夾持,由北東向南西分別為紅河斷裂、哀牢山斷裂以及阿墨江斷裂,不同時(shí)期哀牢山結(jié)合帶內(nèi)各斷裂的活躍造成不同時(shí)期侵入巖的發(fā)育。本文以構(gòu)造-巖漿理論指導(dǎo),對(duì)研究區(qū)侵入巖巖石學(xué)特征、巖石化學(xué)特征進(jìn)行了系統(tǒng)研究。研究區(qū)侵入巖主要分布在哀牢山結(jié)合帶內(nèi)及兩側(cè),根據(jù)SHRIMP鋯石U-Pb測(cè)年結(jié)果可知,研究區(qū)侵入巖主要包括印支期及喜山期侵入,喜山期巖體數(shù)量為4個(gè),年齡在33~35Ma之間,印支其2個(gè),年齡在194~234Ma之間。其中阿扎魯小村巖體經(jīng)過(guò)野外觀察及室內(nèi)薄片鑒定得出其分為兩期侵入,第一期侵入體SHRIMP鋯石U-Pb測(cè)年其年齡屬印支期;第二期未采得年齡樣,根據(jù)野外觀察及室內(nèi)薄片鑒定并與其他喜山期巖體對(duì)比認(rèn)為屬喜馬拉雅期侵入。研究區(qū)侵入巖全部為中-酸性侵入巖類,其中,路旁郎巖體為肉紅色黑云母石英二長(zhǎng)閃長(zhǎng)玢巖、肉紅色黑云母石英閃長(zhǎng)玢巖、紫灰色黑云母石英二長(zhǎng)閃長(zhǎng)玢巖等的淺成相的閃長(zhǎng)玢巖巖體。舊村巖體為灰白色花崗質(zhì)糜棱巖、糜棱巖化花崗巖、花崗質(zhì)初糜巖、花崗質(zhì)片巖等組成的經(jīng)動(dòng)力變質(zhì)的花崗巖。阿扎魯小村巖體第一期是糜棱巖化二長(zhǎng)花崗巖,第二期巖體為堿長(zhǎng)白云母花崗斑巖。阿求和巖體為二長(zhǎng)花崗巖、鉀長(zhǎng)花崗巖組成以二長(zhǎng)花崗巖為主的巖體。團(tuán)田山巖體為黑云母石英正長(zhǎng)巖及少量黑云母石英二長(zhǎng)巖。研究區(qū)喜山期巖體屬于哀牢山-紅河斷裂帶新生代富堿侵入巖,喜山期巖體地球化學(xué)特征為:樣品Si O2平均值為72.28%,屬于酸性巖類,根據(jù)其地球化學(xué)特征分析結(jié)果其屬于過(guò)堿質(zhì)-過(guò)鋁質(zhì)過(guò)度系列,為堿性巖類,微量及稀土元素特征為明顯富集Ba、K大離子親石元素(LILE),虧損Ta、Nb、P、Ti等高場(chǎng)強(qiáng)元素(HFSE)。稀土元素輕重稀土分餾,屬于輕稀土富集型,Eu具輕微的負(fù)異常。印支期巖體地球化學(xué)特征是為:樣品Si O2含量平均值為62.23%,為中-酸性巖體,為過(guò)鋁質(zhì)系列。Na2O大于K2O,巖體為堿性系列。微量元素富集Th、U、Pb等,虧損Ba、Ta、Nb、P、Ti等,總體上表現(xiàn)為高場(chǎng)強(qiáng)元素(HFSE)變化較大,大離子親石元素貧富變化不明顯,稀土元素輕重稀土分餾,屬于輕稀土富集型。δEu平均值為0.75,Eu具輕微的負(fù)異常,表明部分熔融源區(qū)無(wú)斜長(zhǎng)石殘留或巖石形成中未發(fā)生斜長(zhǎng)石結(jié)晶分離。喜山期巖體為鋁質(zhì)A型花崗巖,巖漿可能來(lái)自于地殼的硅鋁層,起源于較為淺的源區(qū),巖漿上升過(guò)程中并未明顯受到同化混染及結(jié)晶分異作用。構(gòu)造背景處于造山晚期-造山期后的拉伸環(huán)境。印支期巖體為S型花崗巖,巖漿起源于淺部源區(qū),巖漿上升侵位過(guò)程中收到少量幔源巖漿的混染,構(gòu)造背景為同碰撞的晚造山期花崗巖。
[Abstract]:The Ailaoshan binding belt, which has undergone the late Paleozoic to early Mesozoic Tethys evolution, and the Cenozoic Indian plate-Eurasian plate collision, is an important tectonic transition response zone. In the Ailaoshan junction zone of the study area, it is held by three regional deep faults, from the north east to the south west of the red river fault, the Ailaoshan fault and the amojiang fault. The active faults in the Ailaoshan binding zone in different periods resulted in the development of intrusive rocks in different periods. Under the guidance of tectonic-magmatic theory, the petrological and petrochemical characteristics of intrusive rocks in the study area are systematically studied in this paper. The intrusive rocks in the study area are mainly distributed in and on both sides of the Ailaoshan binding zone. According to the SHRIMP zircon U-Pb dating results, the intrusive rocks in the study area mainly include Indosinian and Himalayan intrusions, and the number of Himalayan intrusions is 4, and the age is between 33~35Ma. Indosinian 2 of them, between the age of 194~234Ma. The Azzaru Xiaocun rock mass is divided into two stages by field observation and laboratory sheet identification. The first stage SHRIMP zircon U-Pb dating of the intrusive body belongs to the Indosinian age. In the second stage, it is considered to be Himalayan intrusive according to field observation and laboratory sheet identification and comparison with other Himalayan rock bodies. The intrusive rocks in the study area are all intermediate-acid intrusive rocks. Among them, the Lubenlang intrusive body consists of meat-red biotite quartz diorite porphyrite and meat-red biotite quartz diorite porphyrite. Purple gray biotite quartz diorite porphyrite, etc. The Jiucun granite is composed of grayish-white granitic mylonite mylonitic granite granitic primary mylonite granitic schist and other dynamic metamorphic granite. The first stage of the Xiaocun rock body in Azalu is mylonitic monzogranite, and the second stage is the alkali Muscovite granitic porphyry. The ansuonghe rock body is a monzomorphic granite, and the potassium feldspar granite is composed of two-feldspar granites. TuanTian Shan rock body is biotite quartz syenite and a few biotite quartz monzonite. The Xishan rock mass belongs to the Cenozoic alkali rich intrusive rocks in the Ailaoshan-Honghe fault zone. The geochemical characteristics of the Himalayan rocks are as follows: the average value of sample Si O 2 is 72.28, which belongs to acidic rocks. According to the analysis of its geochemical characteristics, it belongs to the peralkaline-peraluminous transitional series and belongs to alkaline rocks. Trace and rare earth elements are characterized by obvious enrichment of Ba,K large ion lithophile element (LILE), depleted Ta,Nb,P,. Ti isopotential field strength element (HFSE). REE fractionation belongs to LREE enrichment type and Eu has slight negative anomaly. The geochemical characteristics of the Indosinian rock mass are as follows: the average Si O 2 content of the sample is 62.23, the intermediate acid rock mass is peraluminous series, the Na2O is larger than K 2O, and the rock mass is alkaline series. Trace elements are enriched in Th,U,Pb, depleted in Ba,Ta,Nb,P,Ti, and so on. In general, the high field strength element (HFSE) changes greatly, the large ion lithophile element does not change obviously, and the rare earth elements are fractionated by light and light rare earth elements. The 未 Eu average value is 0.75% EU with a slight negative anomaly, indicating that there is no plagioclase residue or no plagioclase crystallization separation in the formation of rocks. The Xishan rock body is aluminous A-type granite. The magma may come from the silica-aluminum layer of the crust and originate from a relatively shallow source area. The magma was not obviously assimilated and mixed and crystallized during the process of magma rise. The tectonic setting is in the late orogenic and post-orogenic extensional environment. The Indosinian rock mass is S-type granite, magma originated from shallow source area, a small amount of mantle magma was mixed in the process of magmatic emplacement, and the tectonic setting was a colliding late orogenic granite.
【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)】：P588.12
本文編號(hào)：2360586
[Abstract]:The Ailaoshan binding belt, which has undergone the late Paleozoic to early Mesozoic Tethys evolution, and the Cenozoic Indian plate-Eurasian plate collision, is an important tectonic transition response zone. In the Ailaoshan junction zone of the study area, it is held by three regional deep faults, from the north east to the south west of the red river fault, the Ailaoshan fault and the amojiang fault. The active faults in the Ailaoshan binding zone in different periods resulted in the development of intrusive rocks in different periods. Under the guidance of tectonic-magmatic theory, the petrological and petrochemical characteristics of intrusive rocks in the study area are systematically studied in this paper. The intrusive rocks in the study area are mainly distributed in and on both sides of the Ailaoshan binding zone. According to the SHRIMP zircon U-Pb dating results, the intrusive rocks in the study area mainly include Indosinian and Himalayan intrusions, and the number of Himalayan intrusions is 4, and the age is between 33~35Ma. Indosinian 2 of them, between the age of 194~234Ma. The Azzaru Xiaocun rock mass is divided into two stages by field observation and laboratory sheet identification. The first stage SHRIMP zircon U-Pb dating of the intrusive body belongs to the Indosinian age. In the second stage, it is considered to be Himalayan intrusive according to field observation and laboratory sheet identification and comparison with other Himalayan rock bodies. The intrusive rocks in the study area are all intermediate-acid intrusive rocks. Among them, the Lubenlang intrusive body consists of meat-red biotite quartz diorite porphyrite and meat-red biotite quartz diorite porphyrite. Purple gray biotite quartz diorite porphyrite, etc. The Jiucun granite is composed of grayish-white granitic mylonite mylonitic granite granitic primary mylonite granitic schist and other dynamic metamorphic granite. The first stage of the Xiaocun rock body in Azalu is mylonitic monzogranite, and the second stage is the alkali Muscovite granitic porphyry. The ansuonghe rock body is a monzomorphic granite, and the potassium feldspar granite is composed of two-feldspar granites. TuanTian Shan rock body is biotite quartz syenite and a few biotite quartz monzonite. The Xishan rock mass belongs to the Cenozoic alkali rich intrusive rocks in the Ailaoshan-Honghe fault zone. The geochemical characteristics of the Himalayan rocks are as follows: the average value of sample Si O 2 is 72.28, which belongs to acidic rocks. According to the analysis of its geochemical characteristics, it belongs to the peralkaline-peraluminous transitional series and belongs to alkaline rocks. Trace and rare earth elements are characterized by obvious enrichment of Ba,K large ion lithophile element (LILE), depleted Ta,Nb,P,. Ti isopotential field strength element (HFSE). REE fractionation belongs to LREE enrichment type and Eu has slight negative anomaly. The geochemical characteristics of the Indosinian rock mass are as follows: the average Si O 2 content of the sample is 62.23, the intermediate acid rock mass is peraluminous series, the Na2O is larger than K 2O, and the rock mass is alkaline series. Trace elements are enriched in Th,U,Pb, depleted in Ba,Ta,Nb,P,Ti, and so on. In general, the high field strength element (HFSE) changes greatly, the large ion lithophile element does not change obviously, and the rare earth elements are fractionated by light and light rare earth elements. The 未 Eu average value is 0.75% EU with a slight negative anomaly, indicating that there is no plagioclase residue or no plagioclase crystallization separation in the formation of rocks. The Xishan rock body is aluminous A-type granite. The magma may come from the silica-aluminum layer of the crust and originate from a relatively shallow source area. The magma was not obviously assimilated and mixed and crystallized during the process of magma rise. The tectonic setting is in the late orogenic and post-orogenic extensional environment. The Indosinian rock mass is S-type granite, magma originated from shallow source area, a small amount of mantle magma was mixed in the process of magmatic emplacement, and the tectonic setting was a colliding late orogenic granite.
【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)】：P588.12
【參考文獻(xiàn)】
相關(guān)期刊論文 前1條
1 張旗，周德進(jìn)，趙大升，彭興階，羅萬(wàn)林，，劉祥品;滇西古特提斯造山帶的威爾遜旋回：巖漿活動(dòng)記錄和深部過(guò)程討論[J];巖石學(xué)報(bào);1996年01期
本文編號(hào)：2360586
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