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71.
WANG Chan LIU Hao DENG Jianghong LIU Xianfan ZHAO Fufeng WANG Chun TIAN Xin 《《地质学报》英文版》2018,92(2):482-498
The Jiajiwaxi pluton in the southern portion of the West Kunlun Range can be divided into two collision–related intrusive rock series, i.e., a gabbro–quartz diorite–granodiorite series that formed at 224±2.0 Ma and a monzonitic granite–syenogranite series that formed at 222±2.0 Ma. The systematic analysis of zircon U-Pb geochronology and bulk geochemistry is used to discuss the magmatic origin(material source and thermal source), tectonic setting, genesis and geotectonic implications of these rocks. The results of this analysis indicate that the parent magma of the first series, representing a transition from I-type to S-type granites, formed from thermally triggered partial melting of deep crustal components in an early island–arc–type igneous complex, similar to an I-type granite, during the continental collision orogenic stage. The parent magma of the second series, corresponding to an S-type granite, formed from the partial melting of forearc accretionary wedge sediments in a subduction zone in the late Palaeozoic–Triassic. During continued collision, the second series magma was emplaced into the first series pluton along a central fault zone in the original island arc region, forming an immiscible puncture-type complex. The deep tectonothermal events associated with the continent–continent collision during the orogenic cycle are constrained by the compositions and origins of the two series. The new information provided by this paper will aid in future research into the dynamic mechanisms affecting magmatic evolution in the West Kunlun orogenic belt. 相似文献
72.
为提高“松科二井”在深井硬岩钻进中的寿命与效率,选用了高性能胎体材料、高强度焊接材料,并采用了合理的钻头结构与水路结构设计,研制的φ216/124 mm金刚石取心钻头在“松科二井”取得了良好的效果,本文介绍了适用于深井硬岩的金刚石钻头的设计及应用效果。 相似文献
73.
Yongquan Hu Qiang Wang Jinzhou Zhao Ziyi Guo Yong Zhang Chun Mao 《Environmental Earth Sciences》2018,77(23):778
The aim of the study involves examining the effect of heavy oil viscosity on fracture geometry in detail by establishing a heavy oil fracturing model and conventional fracturing model based on thermal–hydraulic–mechanical (THM) coupled theory, Walther viscosity model, and K–D–R temperature model. We consider viscosity and density within the heavy oil fracturing model as functions of pressure and temperature while that as constants within the conventional fracturing model. A heavy oil production well is set as an example to analyze the differences between the two models to account for the thermo-poro-elastic effect. The results show that temperature exhibits the most significant influence on the heavy oil viscosity while the influence of pressure is the least. In addition, a cooling area with a width of 0–1 m and varied length is generated near the fracture. The heavy oil viscosity increases sharply in this area, thereby indicating an area of viscosity increment. The heavy oil viscosity increases faster and is closer to wellbore, and a high viscosity increment reduces the mobility of the heavy oil and prevents the fracturing fluid from entering into the reservoir. The special viscosity distribution results in significant differences in pore pressure, oil saturation, and changing trends between these two models. In the heavy oil reservoir fracturing model, the thermal effect completely exceeds the influence of pore elasticity, and the values of the fracture length, width, and static pressure exceed those calculated in the conventional fracturing model. Thus, a comparison of the measured values indicates that the results obtained by considering viscosity as a function of temperature and pressure are more accurate. Therefore, the results of this study are expected to provide good guidelines for the design of heavy oil fracturing. 相似文献
74.
75.
Position-domain integrity risk-based ambiguity validation for the integer bootstrap estimator 总被引:1,自引:0,他引:1
Integrity monitoring for ambiguity resolution is of significance for utilizing the high-precision carrier phase differential positioning for safety–critical navigational applications. The integer bootstrap estimator can provide an analytical probability density function, which enables the precise evaluation of the integrity risk for ambiguity validation. In order to monitor the effect of unknown ambiguity bias on the integer bootstrap estimator, the position-domain integrity risk of the integer bootstrapped baseline is evaluated under the complete failure modes by using the worst-case protection principle. Furthermore, a partial ambiguity resolution method is developed in order to satisfy the predefined integrity risk requirement. Static and kinematic experiments are carried out to test the proposed method by comparing with the traditional ratio test method and the protection level-based method. The static experimental result has shown that the proposed method can achieve a significant global availability improvement by 51% at most. The kinematic result reveals that the proposed method obtains the best balance between the positioning accuracy and the continuity performance. 相似文献
76.
针对辽宁省的教育与产业之间的关联程度,本文借助灰色关联模型,探究了辽宁省的教育与产业结构之间的关联度。结果表明:辽宁省城市综合实力越强,产业系统与教育系统之间的关联程度就越大;辽宁省正在逐步趋于合理地调整和优化产业结构的布局,逐渐注重第三产业的发展,并以此为动力来推动第一和第二产业的发展前进;教育结构是否合理会对产业结构产生直接或间接的影响,调整和优化产业结构需要长时间来寻找一条最优路径,需要逐步引导教育结构与之相适应。 相似文献
77.
Yu Shibo Yang Xiaocong Zhu Chun Yuan Ye Wang Zhixiu 《Geotechnical and Geological Engineering》2021,39(6):4113-4125
Geotechnical and Geological Engineering - Using a detailed modeling simulation technology, a mechanics simulation model was constructed, including multiple development rounds, stress relief holes... 相似文献
78.
79.
四川石棉西部地区金矿床形成时代 总被引:2,自引:0,他引:2
四川石棉西部地区金矿床和矿点分布在扬子地块盖层碳酸盐岩和基底元古宙变质闪长岩以及中生代石英斑岩中的北北西和北北东走向断裂中。矿脉为含金黄铁矿-(黝铜矿)-多金属硫化物-石英脉、含金黄铁矿-石英脉和含金硅化糜陵岩等,围岩蚀变为硅化、白(绢)云母化、碳酸盐化、绿泥石化和黄铁矿化等。用40^Ar/39^Ar阶段加热法测定瓦斯沟、黄水沟、大岩房、金洞子和金台子5个金矿床蚀变白云母。4^Ar/39^Ar坪年龄分别为约22Ma、25~28Ma、20Ma、20Ma和32-34Ma,代表该地区主要金矿床的矿化蚀变时间。石棉西部地区金矿床是在渐新世和中新世早期的伸展构造背景下形成的。 相似文献
80.
Hiroaki Sasaki Akihiko Tanaka Mitsunori Iwataki Yasuharu Touke Eko Siswanto Chun Knee Tan Joji Ishizaka 《Journal of Oceanography》2008,64(4):511-523
Remote sensing reflectance [R
rs(λ)] and absorption coefficients of red tides were measured in Isahaya Bay, southwestern Japan, to investigate differences in
the optical properties of red tide and non-red tide waters. We defined colored areas of the sea surface, visualized from shipboard,
as “red tides”. Peaks of the R
rs(λ) spectra of non-red tide waters were at 565 nm, while those of red tides shifted to longer wavelengths (589 nm). The spectral
shape of R
rs(λ) was close to that of the reciprocal of the total absorption coefficient [1/a(λ)], implying that the R
rs(λ) peak is determined by absorption. Absorption coefficients of phytoplankton [a
ph(λ)], non-pigment particles and colored dissolved organic matter increased with increasing chlorophyll a concentration (Chl a), and those coefficients were correlated with Chl a for both red tide and non-red tide waters. Using these relationships between absorption coefficients and Chl a, variation in the spectrum of 1/a(λ) as a function of Chl a was calculated. The peak of 1/a(λ) shifted to longer wavelengths with increasing Chl a. Furthermore, the relative contribution of a
ph(λ) to the total absorption in red tide water was significantly higher than in non-red tide water in the wavelength range 550–600
nm, including the peak. Our results show that the variation of a
ph(λ) with Chl a dominates the behavior of the R
rs(λ) peak, and utilization of R
rs(λ) peaks at 589 and 565 nm may be useful to discriminate between red tide and non-red tide waters by remote sensing. 相似文献