發(fā)布時間：2018-02-22 23:59

  本文關(guān)鍵詞： 本巴圖組 構(gòu)造屬性 構(gòu)造演化 三期褶皺 疊加　出處：《中國地質(zhì)大學(xué)(北京)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：研究區(qū)位于中蒙邊境附近,處于華北板塊西北陸緣活動帶上,經(jīng)歷了復(fù)雜的地質(zhì)演化過程,受到不同構(gòu)造單元和構(gòu)造演化階段的影響,大地構(gòu)造位置十分重要,但由于研究區(qū)內(nèi)自然環(huán)境惡劣,研究程度較低。本次研究的目的主要是通過對阿拉善盟恩格爾烏蘇地區(qū)1:5萬地質(zhì)圖進行初步分析,結(jié)合野外褶皺構(gòu)造形態(tài)地質(zhì)調(diào)查。對恩格爾烏蘇一帶本巴圖組的構(gòu)造屬性,運動演化進行分析,從而建立起比較完整的構(gòu)造演化框架并對區(qū)域大地構(gòu)造意義進行有益的探討。通過詳細的野外地質(zhì)調(diào)查,在前人的基礎(chǔ)上新的發(fā)現(xiàn)和認(rèn)識有:研究區(qū)中發(fā)育有三期褶皺相互疊加改造,樞紐主要呈SE、SW、近EW及近NS向展布。早期褶皺為一期同斜倒轉(zhuǎn)褶皺,為地層原始層理的褶皺,由于后期褶皺的疊加作用,早期構(gòu)造形跡發(fā)育的比較分散,反映了巖層初始階段受到順層剪切作用而形成。中期褶皺為本巴圖組構(gòu)造規(guī)模最大的一期,軸跡近EW向,為恩格爾烏蘇斷裂帶碰撞造山作用產(chǎn)生的近NS向擠壓力作用于恩格爾烏蘇南部的本巴圖組而形成的,由于晚期褶皺疊加改造,中期褶皺的軸跡發(fā)生波狀彎曲。晚期褶皺的主應(yīng)力方位發(fā)生改變,受近EW向擠壓作用,形成寬緩褶皺。晚期褶皺構(gòu)造的形成存在兩個方面的可能。一方面原因是恩格爾烏蘇斷裂帶碰撞造山作用之后會出現(xiàn)應(yīng)力松弛,主應(yīng)力發(fā)生變化,從而形成第三期近NS向?qū)捑忨薨櫋Ａ硪环矫嫜嗌狡诘闹袊�大陸的板�?nèi)變性特征為形成一系列NNE或NE向縱彎褶皺,且構(gòu)造運動強度總體呈現(xiàn)東強西弱的特征。此外燕山期的褶皺軸向按時間順序,從早到晚,構(gòu)造線呈現(xiàn)為逆時針轉(zhuǎn)動,本巴圖組第三期褶皺的形成可能與其相關(guān)。
[Abstract]:The study area is located in the border near the North China plate in the northwest margin active belt, has experienced complex geological evolution process, affected by the different tectonic units and tectonic evolution stage, tectonic position is very important, but because of the natural environment in the study area is bad, the lower the degree of research. The aim of this study is to a preliminary analysis based on 1:5 000 geological maps Alashan Engel Wusu region, combined with field geological survey form folds. The tectonic attribute of Engel Wusu group Bartle, evolution analysis, so as to establish a relatively complete framework and tectonic evolution are explored on the regional tectonic significance. Through detailed geological survey and on the basis of previous discoveries and understanding: in the study area for a period of three superimposed fold development transformation, mainly in the hub SE, SW, near EW and near The NS trending folds. Early for a period of homoclinal overturned fold, for the formation of original bedding folds due to superposition. The late fold, scattered early structural development, reflects the initial stage of rock by bedding shearing formed. The mid fold for a period of the Bartle group structure of the largest axis near EW, near NS for Engel Wusu fracture belt collision orogeny to pressure on the Bartle group Engel Southern Wusu formed, due to the late superimposed fold, fold the middle axis bending. Late wavy folds of the principal stress orientation changed by near EW extrusion effect of the formation of broad folds. Folds formed in late may exist in two aspects. One reason is the Engel fault belt after collision orogeny Ursula will appear stress relaxation, stress change, thus forming Third close to NS fold. Chinese, changeable plate on the other hand Yanshan period in the formation of a series of NNE or NE fold to longitudinal bending, and the intensity of tectonic movement shows the characteristics of strong and weak in the West. In addition Yanshan fold axial period according to the time sequence, from morning to night, construct line showing rotation for the counterclockwise, forming the Bartle group third fold may be related.

【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】：P548

【參考文獻】

相關(guān)期刊論文 前1條

1 李俊建;羅鎮(zhèn)寬;燕長海;謝汝斌;李德勝;李洪奎;駱輝;劉曉陽;劉曉雪;李生;;華北陸塊的構(gòu)造格局及其演化[J];地質(zhì)找礦論叢;2010年02期

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本文編號：1525636