發(fā)布時間：2019-04-30 08:51

【摘要】：羌塘地塊內(nèi)發(fā)育大面積的陸相紅色地層,主要為山間河湖相沉積以及少量磨拉石建造。前人對這些紅層的研究程度一直較低,但它們卻是記錄羌塘地體乃至整個青藏高原新生代的隆升過程的最好載體。位于南羌塘北緣的榮瑪?shù)貐^(qū),發(fā)育了大套紅色河湖相地層,前人一致將它們統(tǒng)一劃歸為漸新世—中新世康托組。但現(xiàn)有區(qū)域資料顯示區(qū)內(nèi)應(yīng)該發(fā)育有晚白堊世陸相紅色碎屑巖地層。本文通過實測剖面,并從沉積學(xué)、巖相學(xué)、同位素年代學(xué)和構(gòu)造變形等多方面分析測區(qū)新生代盆地演化和構(gòu)造活動,并對紅層重礦物、物源區(qū)構(gòu)造背景、古流向、沉積相進行探討,最后利用紅層構(gòu)造變形樣式的區(qū)別,輔助加以約束地層時代。沉積學(xué)研究顯示,區(qū)內(nèi)紅色地層主要為沖積扇—濱淺湖—湖泊扇三角洲—辮狀河相地層;Dickinson砂巖碎屑成分三角圖解顯示紅層物源區(qū)構(gòu)造背景主要為再旋回造山帶;古流向研究結(jié)果指示了沉積盆地周緣造山帶不同階段差異隆升的特征;重礦物分析得到不同紅層物源區(qū)距離和母巖類型的差異;砂巖碎屑鋯石U-Pb測年結(jié)果證實了區(qū)內(nèi)存在白堊紀地層的可能;地層構(gòu)造變形的研究則較為準確的將區(qū)內(nèi)紅層劃分為兩個構(gòu)造層次。最后從依布茶卡湖東的原康托組中分解出上白堊統(tǒng)阿布山組(~105Ma),充實了研究區(qū)地層單元。
[Abstract]:A large area of continental red strata is developed in Qiangtang block, mainly intermountain fluvial-lacustrine deposits and a small amount of grinding rock formation. Previous studies on these red beds have been low, but they are the best carriers to record the Cenozoic uplift process of the Qiangtang terrane and even the entire Qinghai-Tibet Plateau. Located in the northern margin of southern Qiangtang, a large set of red fluvial and lacustrine facies strata have been developed in the Rongma area, which were unanimously classified into the Oligocene-Miocene Kangtuo formation. However, the available regional data indicate that there should be red clastic strata of late Cretaceous continental facies in the area. In this paper, the evolution and tectonic activity of Cenozoic basin in the survey area are analyzed from the aspects of sedimentary, lithofacies, isotope chronology and tectonic deformation, and the heavy minerals in red bed, the tectonic background of provenance area, and the paleo-direction are analyzed through the measured sections. The sedimentary facies is discussed, and finally, the difference of the deformation pattern of red bed structure is used to restrain the stratigraphic age. Sedimentological studies show that the red strata in the area are mainly alluvial fan-shoreline shallow lake-lacustrine fan delta-braided river facies strata, and the triangle diagram of the clastic composition of Dickinson sandstone shows that the tectonic setting of the red bed provenance area is mainly the recirculation orogenic belt. The results of paleo-flow study indicate the characteristics of different stages of uplift in the orogenic belts around the sedimentary basin, and the differences in the distance between the source areas of different red beds and the types of parent rocks from the analysis of heavy minerals. The results of U-Pb dating of sandstone clastic zircon confirm the possibility of Cretaceous strata in the area, and the study of stratigraphic structural deformation accurately divides the red strata into two tectonic levels. Finally, the Upper Cretaceous Abu Shan formation (~ 105Ma) is decomposed from the Yuankangtuo formation in the east of Ibuchaka Lake, which enriches the stratigraphic unit of the study area.
【學(xué)位授予單位】：中國地質(zhì)大學(xué)(北京)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：P535

【相似文獻】

相關(guān)期刊論文 前3條

1 李才;黃小鵬;牟世勇;遲效國;;藏北羌塘南部走構(gòu)由茶錯地區(qū)火山巖定年與康托組時代的厘定[J];地質(zhì)通報;2006年Z1期

2 鐘華明;劉俊;童勁松;夏軍;魯如魁;;羌塘西北部松西地區(qū)康托組火山巖年齡及意義[J];安徽地質(zhì);2008年02期

3 ;[J];;年期

相關(guān)會議論文 前1條

1 丁繼凱;張世紅;李海燕;吳懷春;楊天水;諶微微;張均紅;;青藏高原漸新統(tǒng)康托組紅層古地磁結(jié)果及其大地構(gòu)造意義[A];中國地球物理2013——第五專題論文集[C];2013年

相關(guān)碩士學(xué)位論文 前2條

1 王寒凍;藏北依布茶卡東康托組重新厘定[D];中國地質(zhì)大學(xué)(北京);2015年

2 丁繼凱;青藏高原漸新世康托組紅層古地磁結(jié)果及其大地構(gòu)造意義[D];中國地質(zhì)大學(xué)（北京）;2014年

，

本文編號：2468654