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81.
制备TJ-1模拟月壤空心圆柱试样的新方法   总被引:1,自引:0,他引:1  
针对TJ-1模拟月壤颗粒级配跨度大、粒径〉2mm.的颗粒含量多,采用常规方法制备空心圆柱试样容易出现粗细颗粒分离、试样整体不均匀的特点,提出改良型制备方法.首先采用分层欠压法与冰冻法相结合制备出孔隙比e=1.0的实心圆柱试样,并对实心样的均匀性进行评价,得到分层制备相同孔隙比的TJ-1模拟月壤均匀试样时每层试样的高度;...  相似文献   
82.
天山乌鲁木齐河源1号冰川径流对气候变化的响应分析   总被引:10,自引:6,他引:4  
利用天山乌鲁木齐河源1号冰川1959-2006年的气象、冰川物质平衡和1980-2006年的水文资料,分析了其冰川径流的变化.结果表明:由于1996年以来的显著升温,导致了1号冰川水文点径流主要受夏季气温变化的控制,冰川物质损失对径流的补给作用已超过了降水的作用.1996-2006年与1980-1995年相比,夏季气温...  相似文献   
83.
珠江口盆地荔湾3-1气田珠江组深水扇沉积相分析   总被引:7,自引:1,他引:6  
根据已钻井取芯段岩相分析,从荔湾3-1气田珠江组深水扇沉积体系中划分出巨厚层和厚层块状砂岩相、厚层正粒序砂岩相、厚层逆粒序砂岩相、平行—板状斜层理砂岩相、滑塌变形砂岩相、薄层砂岩夹层相、薄层(粉)砂岩与泥岩互层相、厚层粉砂岩相、厚层泥岩相和层状深水灰岩相等10种岩相类型和识别出砂岩相组合、泥岩相组合、(粉)砂岩与泥岩互...  相似文献   
84.
锦屏一级水电站坝基无盖重固结灌浆施工工艺探讨   总被引:2,自引:0,他引:2       下载免费PDF全文
杨世伟  李德勇 《探矿工程》2011,38(8):56-58,63
锦屏一级水电站大坝由于基础层混凝土仓面面积大,温控要求严格、间歇期短,固结灌浆施工与坝体混凝土温控存在较大矛盾,主要采取无盖重固结灌浆加有盖重补强固结灌浆及引管的方式进行。主要就无盖重固结灌浆主要存在问题进行了分析和探讨。  相似文献   
85.
Combined with the actual geological settings, tight oil is the oil that occurs in shale or tight reservoirs, which has permeability less than 1 mD and is interbedded with or close to shale, including tight dolomitic oil and shale oil. The Fengcheng area (FA), at the northwest margin of the Junggar Basin, northwest China, has made significant progress in the tight oil exploration of the Fengcheng (P1f) Formation recently, which indicates that the tight oil resources have good exploration prospects. Whereas the lack of recognition of hydrocarbon generation and expulsion characteristics of Permian P1f source rocks results in the misunderstanding of tight oil resource potential. Based on the comprehensive analysis of geological and geochemical characteristics of wells, seismic inversion, sedimentary facies, tectonic burial depth, etc., the characteristics of P1f source rocks were investigated, and the horizontal distributions of the following aspects were predicted: the thickness of source rocks, abundance and type of organic matter. And on this basis, an improved hydrocarbon generation potential methodology together with basin simulation techniques was applied to unravel the petroleum generation and expulsion characteristics of P1f source rocks in FA. Results show that the P1f source rocks distribute widely (up to 2039 km2), are thick (up to 260 m), have high total organic content (TOC, ranging from 0.15 to 4 wt%), are dominated by type II kerogen and have entered into low mature–mature stage. The modeling results indicate that the source rocks reached hydrocarbon generation threshold and hydrocarbon expulsion threshold at 0.5% Ro and 0.85% Ro and the comprehensive hydrocarbon expulsion efficiency was about 46%. The amount of generation and expulsion from the P1f source rocks was 31.85 × 108 and 15.31 × 108 t, respectively, with a residual amount of 16.54 × 108 t within the source rocks. Volumetrically, the geological resource of shale oil is up to 15.65 × 108 t. Small differences between the amounts calculated by the volumetric method compared with that by hydrocarbon generation potential methodology may be due to other oil accumulations present within interbedded sands associated with the oil shales. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
86.
罗布泊北部地区凝结水对地下水补给作用的模拟   总被引:2,自引:0,他引:2  
在含盐量较高的罗布泊北部凹地,采用称重法进行了凝结水的野外监测.利用凝结水的观测资料,基于HYDRUS_1D软件,建立了一维饱和―非饱和模型来模拟预测凝结水对地下水的补给作用.研究结果表明:观测期间试筒质量多为减少,仅有3个时段试筒质量增加,表明在这3个时段有凝结水生成;凝结水对包气带的补给量占包气带水分总收入的50....  相似文献   
87.
In the present study, the modified Sverjensky–Molling equation, derived from a linear-free energy relationship, is used to predict the Gibbs free energies of formation of crystalline phases of α-MOOH (with a goethite structure) and α-M2O3 (with a hematite structure) from the known thermodynamic properties of the corresponding aqueous trivalent cations (M3+). The modified equation is expressed as ΔG0f,MVX=aMVXΔG0n,M3++bMVX+βMVXγM3+, where the coefficients aMVX, bMVX, and βMVX characterize a particular structural family of MvX (M is a trivalent cation [M3+] and X represents the remainder of the composition of solid); γ3+ is the ionic radius of trivalent cations (M3+); ΔG0f,MVX is the standard Gibbs free energy of formation of MvX; and ΔG0n,M3+ is the non-solvation energy of trivalent cations (M3+). By fitting the equation to the known experimental thermodynamic data, the coefficients for the goethite family (α-MOOH) are aMVX=0.8838, bMVX=?424.4431 (kcal/mol), and βMVX=115 (kcal/mol.?), while the coefficients for the hematite family (α-M2O3) are aMVX=1.7468, bMVX=?814.9573 (kcal/mol), and βMVX=278 (kcal/mol.?). The constrained relationship can be used to predict the standard Gibbs free energies of formation of crystalline phases and fictive phases (i.e. phases that are thermodynamically unstable and do not occur at standard conditions) within the isostructural families of goethite (α-MOOH) and hematite (α-M2O3) if the standard Gibbs free energies of formation of the trivalent cations are known.  相似文献   
88.
Early Miocene (ca.?21–18 Ma) volcanism in the Karacada? area comprises three groups of volcanic rocks: (1) calcalkaline suite (andesitic to rhyolitic lavas and their pyroclastics), (2) mildly-alkaline suite (alkali basalt, hawaiite, mugearite, benmoreite and trachydacite), and (3) a single trachyandesitic flow unit. Field observations, 40Ar/39Ar ages and geochemical data show that there was a progressive temporal transition from group 1 to 3 in a post-collisional tectonic setting. The calcalkaline suite rocks with medium-K in composition resemble those of subduction-related lavas, whereas the mildly-alkaline suite rocks having a sodic tendency (Na2O/K2O=1.5–3.2) resemble those of within-plate lavas. Incompatible element and Sr-Nd isotopic characteristics of the suites suggest that the lithospheric mantle beneath the Karacada? area was heterogeneously enriched by two processes before collision: (1) enrichment by subduction-related processes, which is important in the genesis of the calcalkaline volcanism, (2) enrichment by small degree melts from the astenosphere, which dominates the mildly alkaline volcanism. Perturbation of the enriched lithosphere by either delamination following collision and uplift or removal of the subducted slab following subduction and collision (i.e., slab breakoff) is the likely mechanism for the initiation of the post-collision volcanism.  相似文献   
89.
Gamma-ray spectrometer (GRS) is one of the main payloads on the Chang’E-1 (CE-1) lunar probe, mainly aimed to detect the elemental abundances and distributions on the lunar surface. At 03:58 on 28 November 2007, it performed the first observation of the lunar gamma rays. As of 24 October 2008, 2105?h of effective gamma rays spectra had been acquired by CE-1 GRS, which covers the whole surface of the moon. This paper mainly describes the data processing procedures and methods of deriving the elemental abundances by using the CE-1 GRS time series corrected spectra: first, to bin data into pixels for mapping; then, to perform a background deduction of the cumulative spectra and obtain a peak area of the elements; and finally, to use the elemental abundances inversion model to produce the elemental abundances. Based on these processing methods, the global abundance maps of U, K, and Th at a 5°×5° equal-area pixel are acquired by CE-1 GRS data. The paper gives a preliminary analysis of the uncertainties of the elemental abundances  相似文献   
90.
Samples were continuously collected from aerosol, fresh snow, and snow pits on Glacier No. 1 at Urumqi River source in eastern Tianshan (天山) Mountains. The deposition processes and the characteristics of mineral dust microparticles from aerosol to fresh snow, and then evolution to the snow pit were determined. Total dust microparticle concentration in the surface snow and aerosol showed a similar temporal variation trend, which was strongly associated with regional and local at-mospheric circulation in the ...  相似文献   
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