發(fā)布時(shí)間：2018-05-31 22:52

  本文選題：庫車坳陷 + 臨界角庫倫楔公式��； 參考：《南京大學(xué)》2017年碩士論文

【摘要】：臨界角庫倫楔模型的建立,確定了楔狀體坡度與楔狀體和底部滑脫層的巖石力學(xué)性質(zhì)之間的關(guān)系。由公式可得,底面滑脫層的內(nèi)摩擦系數(shù)越大,楔狀體的坡度越大;而巖層的內(nèi)摩擦系數(shù)越大,楔狀體的坡度越小。但對于庫車坳陷克拉蘇構(gòu)造帶鹽下發(fā)育的褶皺沖斷帶楔狀體,由于有上層鹽巖的重量對楔狀體的壓力,運(yùn)用傳統(tǒng)的臨界角庫倫楔公式計(jì)算得到的結(jié)果與實(shí)際不符。本文考慮了上層鹽巖的重量,推導(dǎo)出了適用于鹽下楔狀體的臨界角庫倫楔公式。根據(jù)重新推導(dǎo)后的臨界角庫倫楔公式對庫車坳陷底部滑脫層的性質(zhì)進(jìn)行了計(jì)算,得出底部滑脫層內(nèi)摩擦角為13.4°～18.1°。推測該滑脫層的性質(zhì)與泥巖或碳質(zhì)頁巖的性質(zhì)相符,該滑脫層可能為中三疊統(tǒng)或上三疊統(tǒng)的泥巖或碳質(zhì)頁巖。由重新推導(dǎo)后得出的適用于鹽下楔狀體的臨界角庫倫楔公式和庫車坳陷克拉蘇構(gòu)造帶大北段地震解釋結(jié)果可以得出,越靠近褶皺沖斷帶楔狀體的前鋒的部分,巖層所處的壓力越大,楔狀體的頂面坡度越大。為了驗(yàn)證這一結(jié)論,設(shè)計(jì)了一組離散元數(shù)值模擬實(shí)驗(yàn),實(shí)驗(yàn)的結(jié)果表明,越靠近楔狀體前鋒的頂面坡度越大,而越靠近楔狀體后端,楔狀體的頂面坡度越小。這種現(xiàn)象與臨界角庫倫楔公式和庫車坳陷克拉蘇構(gòu)造帶所反應(yīng)的特點(diǎn)一致。擠壓端出現(xiàn)了一個(gè)反沖斷層,各個(gè)逆沖斷層之間位置間隔距離比較遠(yuǎn)。分析這些現(xiàn)象的原因可能都是因?yàn)樯细阐}巖的壓力造成的。物理模擬的結(jié)果也出現(xiàn)類似的現(xiàn)象,推測膏鹽層的存在在縱向上的壓力會(huì)使地層向下旋轉(zhuǎn),而在橫向上由于膏鹽層沿著楔狀體頂面向前流動(dòng),又會(huì)使推覆體在向前逆沖時(shí)受到阻力。
[Abstract]:With the establishment of the critical angle Coulomb model, the relationship between the slope of the wedge and the rock mechanical properties of the wedge and the bottom slippage is determined. According to the formula, the greater the internal friction coefficient of the bottom slip layer, the bigger the slope of the wedge-like body, while the larger the internal friction coefficient of the rock layer, the smaller the slope of the wedge-like body. However, for the wedge-shaped fold thrust belt developed under salt in the Klassou structural belt of Kuqa depression, due to the pressure of the weight of the upper salt rock on the wedge body, the results obtained by using the traditional Coulomb wedge formula of critical angle are not consistent with the actual situation. In this paper, the critical angle Coulomb wedge formula suitable for wedge body under salt is derived by considering the weight of upper salt rock. The properties of the slip layer at the bottom of the Kuqa depression are calculated according to the re-derived critical angle Coulomb wedge formula. The internal friction angle of the bottom slip layer is 13.4 擄/ 18.1 擄. It is inferred that the nature of the detachment is consistent with that of mudstone or carbonaceous shale, and the detachment may be mudstone or carbonaceous shale of middle Triassic or upper Triassic. The critical angle Coulomb wedge formula for subsalt wedges and seismic interpretation results of the Klassou tectonic belt in Kuqa depression can be obtained from the derivation of the critical angle Coulomb wedge formula and the seismic interpretation results show that it is closer to the front part of the wedge body in the fold-thrust belt. The greater the pressure, the greater the top slope of the wedge. In order to verify this conclusion, a group of discrete element numerical simulation experiments are designed. The experimental results show that the more close to the front of the wedge, the bigger the slope of the top surface, and the smaller the slope of the top surface of the wedge is the closer it is to the back end of the wedge. This phenomenon is consistent with the characteristics of the critical angle Coulomb wedge formula and the Klassou tectonic belt in Kuqa depression. A recoil fault appeared at the extrusion end, and the distance between the thrust faults was relatively long. The analysis of these phenomena may be due to the pressure of the overlying salt rock. A similar phenomenon appears in the physical simulation. It is assumed that the vertical pressure of the gypsum salt layer will cause the formation to rotate downwards, and laterally because the gypsum salt layer flows forward along the top surface of the wedge body, In turn, the nappe will be subjected to resistance in the forward thrust.
【學(xué)位授予單位】：南京大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：P548

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 余海波;漆家福;楊憲章;劉騏\，

本文編號(hào)：1961669