本文選題：興地塔格巖群　切入點(diǎn)：鋯石U-Pb年齡　出處：《新疆大學(xué)》2017年碩士論文

【摘要】：本研究在新疆興地塔格阿訇口地區(qū)1:5萬(wàn)區(qū)域地質(zhì)調(diào)查項(xiàng)目的基礎(chǔ)上,對(duì)庫(kù)魯克塔格地區(qū)古元古界興地塔格巖群巖石樣品的巖相學(xué)、鋯石U-Pb年齡分析、鋯石成因分析及變質(zhì)相分析,確定樣品的巖性、鋯石的年齡特征、鋯石的稀土元素特征、鋯石的成因及樣品變質(zhì)程度,為庫(kù)魯克塔格地區(qū)古元古界興地塔格巖群研究提供證據(jù)。為我們對(duì)塔里木克拉通年代學(xué)的研究,也有著十分重要的意義。巖相學(xué)研究表明,樣品為含石墨石榴長(zhǎng)石石英巖,為角閃巖相變質(zhì)成因。對(duì)80個(gè)鋯石U-Pb年齡點(diǎn)進(jìn)行測(cè)年及CL圖像分析,發(fā)現(xiàn)樣品中最古老的鋯石年齡為2666±10Ma,最年輕的鋯石為1838±21Ma。絕大多數(shù)鋯石都為變質(zhì)成因,內(nèi)部結(jié)構(gòu)多數(shù)呈弱分帶特征,能識(shí)別出核部和變質(zhì)增生邊。部分變質(zhì)鋯石為典型的角閃巖相,發(fā)育巖漿巖內(nèi)核及變質(zhì)增生邊。變質(zhì)成因的年齡分布在2100~1800Ma之間,變質(zhì)作用主峰值期為1910Ma,反映出研究區(qū)受到2.0~1.8Ga變質(zhì)作用影響。對(duì)64組鋯石元素地球化學(xué)數(shù)據(jù)進(jìn)行分析,在球粒隕石標(biāo)準(zhǔn)化圖中,樣品均呈輕稀土(LREE)虧損,重稀土(HREE)總體富集、明顯Ce正異常和Eu負(fù)異常的特征。鋯石稀土總量較高(260.6ppm-11915.6ppm,平均3719.7ppm),變化范圍較大,具有兩分的特征,260.7-996.1ppm和1536.3-11915.6ppm兩組,重稀土元素含量也呈現(xiàn)兩分特征,部分樣品具有重稀土虧損的現(xiàn)象。(Pr/Gd)CN-(Gd/Yb)CN圖解中,顯示也存在明顯的兩分特征。呈重稀土(HREE)虧損的特征的測(cè)點(diǎn)鋯石,與麻粒巖相變質(zhì)條件具有一致性,而另一部分測(cè)點(diǎn)鋯石則呈重稀土(HREE)富集的特征,與角閃巖相變質(zhì)條件具有一致性。綜合分析認(rèn)為鋯石核部具有角閃巖相和麻粒巖相變質(zhì)條件雙重特征,而變質(zhì)增生部分鋯石是在角閃巖相變質(zhì)條件形成的。
[Abstract]:On the basis of the 1: 50 000 regional geological survey project in Xinjiang Xingdi Taag Akunkou area, the lithofacies and zircon U-Pb age of the paleoproterozoic Xingdi tag rock group in Kuluktag area were analyzed.The genetic analysis and metamorphic facies analysis of zircon determine the lithology of the sample, the age characteristics of zircon, the characteristics of rare earth elements of zircon, the origin of zircon and the degree of metamorphism of the sample, which provide evidence for the study of paleoproterozoic Xingdi tag rock group in Kuluktag area.It is also of great significance for us to study the Tarim craton chronology.The petrographic study shows that the samples are graphite-bearing garnet feldspar quartzite and amphibolite facies metamorphic origin.The dating of 80 zircon U-Pb sites and CL image analysis show that the oldest zircon age is 2666 鹵10 Ma and the youngest zircon is 1838 鹵21 Ma.Most zircons are metamorphic, and most of the internal structures are weakly zoned, which can identify the nuclear part and the metamorphic accretive edge.Some metamorphic zircons are typical amphibolite facies, with magmatic core and metamorphic accretive edge.The age distribution of metamorphic origin is between 2100~1800Ma and the main peak period of metamorphism is 1910 Ma, which indicates that the study area is affected by 2.0~1.8Ga metamorphism.Based on the analysis of 64 sets of zircon element geochemistry data, it is found that in the chondrites standardized map, the samples are characterized by LREE (light rare earth) depletion, HREE (heavy rare earth) enrichment, and ce positive anomaly and negative EU anomaly.The display also has obvious dichotomous features.The zircon, which is characterized by HREE (heavy rare earth) depletion, is consistent with the granulite metamorphic condition, while the other part of the zircon is enriched by the heavy rare earth HREE), which is consistent with the amphibolite metamorphic condition.It is considered that the zircon core is characterized by amphibolite facies and granulite facies metamorphism while the metamorphic accretive part of zircon is formed under the amphibolite metamorphic condition.
【學(xué)位授予單位】：新疆大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類(lèi)號(hào)】：P588.3

【相似文獻(xiàn)】

相關(guān)期刊論文 前10條

1 龍曉平;袁超;孫敏;肖文交;趙國(guó)春;周可法;王毓婧;胡靄琴;;庫(kù)魯克塔格地區(qū)最古老巖石的發(fā)現(xiàn)及其地質(zhì)意義[J];中國(guó)科學(xué):地球科學(xué);2011年03期

2 譚澤金,黃智斌,楊芝林,杜品德,張現(xiàn)軍,趙治信;新疆庫(kù)魯克塔格地區(qū)奧陶系賽力克達(dá)坂組的劃分和對(duì)比[J];地層學(xué)雜志;2005年03期

3 劉春花;楊林;尹京武;蔡佳;楊海濤;邵興坤;徐海明;王軍;;新疆庫(kù)魯克塔格興地塔格群中石榴石的礦物學(xué)特征研究[J];巖石礦物學(xué)雜志;2011年02期

4 趙文杰,李長(zhǎng)和,高振家,繆長(zhǎng)泉;新疆庫(kù)魯克塔格南坡帕爾崗塔格群的疊層石[J];古生物學(xué)報(bào);1985年01期

5 郭召杰,劉樹(shù)文,張志誠(chéng);庫(kù)魯克塔格—星星峽是古生代末天山最高地區(qū)[J];新疆地質(zhì);1998年04期

6 蔡志慧;許志琴;唐哲民;何碧竹;陳方遠(yuǎn);;塔里木盆地東北緣庫(kù)魯克塔格地區(qū)的早古生代地殼變形以及造山時(shí)限[J];中國(guó)地質(zhì);2011年04期

7 曹曉峰;呂新彪;高翔;劉月高;朱江;陳超;王于健;劉智;張彬;;新疆庫(kù)魯克塔格前寒武紀(jì)地塊巖漿熱事件及構(gòu)造演化[J];新疆地質(zhì);2012年04期

8 夏昭德;石福品;胡秀軍;姜常義;;新疆庫(kù)魯克塔格地區(qū)興地Ⅱ號(hào)鎂鐵-超鎂鐵質(zhì)巖體的地球化學(xué)特征與巖石成因[J];巖石學(xué)報(bào);2009年04期

9 郭瑞清;秦切;張曉帆;孫寶生;郭寅;;新疆庫(kù)魯克塔格闊克塔格西堿性巖年代學(xué)、巖石地球化學(xué)特征及其地質(zhì)意義[J];吉林大學(xué)學(xué)報(bào)(地球科學(xué)版);2013年02期

10 白雪峰;劉萬(wàn)洙;程日輝;王璞s，

本文編號(hào)：1721440