西昌盆地油气化探普查效果及下一步找油气方向   总被引：1，自引：0，他引：1  

颜自给  樊建强  贾国相  赵友方  何政才 《矿产与地质》2004,18(4):335-338

为了配合国家加快油气资源勘查步伐，四川石油管理局将西昌盆地作为下一步勘探重点地区，由于西昌盆地属勘探新区，各种地质、构造情况复杂，首先在该区实施了油气化探普查，油气化探普查结果证实了西昌盆地中部地区为油气泄漏特征，这与七坝1井结果吻合，同时发现了三个重点区域，指出盆地西部为下一步工作的重点地区，为下一步地震勘探指明找油气方向。  相似文献   

含煤盆地煤储层后期改造形式及对煤层气选区影响--以华北克拉通选区为例     

雷崇利  刘池洋 《煤田地质与勘探》2004,32(2):20-23

阐述了改造型含煤盆地煤储层被改造的两种形式；煤体结构的改造及构造煤的形成原因；后生充填物对煤层孔隙的改造及形成原因。提出了以构造煤发育程度作为改造型含煤盆地改造强度的一个指标。概述了华北克拉通盆地由中生代剪压应力转化为新生代剪张应力和拉张应力，而在盆地内形成以挤压构造为主到伸展构造为主的演化历程，及不同构造类型的区域分布，指出这种演化极易形成构造煤和后生充填物。提出将华北克拉通含煤盆地分为3种改造类型及其分布区域，分析了各自区域的煤储层物性及对煤层气开发选区的影响。提出应重视鄂尔多斯盆地侏罗纪煤层的煤层气．研究与开发．  相似文献   

沉积有机相的研究现状及其应用   总被引：5，自引：0，他引：5       下载免费PDF全文

李君文  陈洪德  田景春  侯中健 《沉积与特提斯地质》2004,24(2):96-100

沉积有机相是近年来国内外广泛运用于油气勘探的一种有效的研究方法。本文介绍了沉积有机相的概念、划分方案，及其在油气勘探、盆地分析和层序地层学中的应用，指出了沉积有机相与层序地层分析相结合对油气资源评价和预测烃源岩有广阔的发展前景。  相似文献   

在MAPGIS下快速实现柱状剖面图的绘制   总被引：4，自引：0，他引：4  

李沙园  陈昕华  戈永怡 《物探化探计算技术》2004,26(2):173-176

将油气化探数据用FORTRAN短程序生成MAPGIS点、线、面明码文件后，再利用MAPGIS图形编辑软件对图形进行编辑加工，达到快速制作油气化探柱状剖面图的目的。使用该方法能充分利用MAPGIS系统资源，降低编制绘图程序的难度。  相似文献   

Numerical simulations for coupled rock deformation and gas leak flow in parallel coal seams   总被引：3，自引：0，他引：3  

Peide Sun> 《Geotechnical and Geological Engineering》2004,22(1):1-17

Based on the new viewpoint of interaction mechanics for solid and gas, gas leakage in parallel deformable coal seams can be understood. That is, under the action of varied geophysical fields, the methane gas flow in a double deformable coal seam can be essentially considered to be compressible with time-dependent and mixed permeation and diffusion through a pore-cleat deformable, heterogeneous and anisotropic medium. From this new viewpoint, coupled mathematical models for coal seam deformation and gas leak flow in parallel coal seams were formulated and the numerical simulations for slow gas emission from the parallel coal seams are presented. It is found that coupled models might be close to reality. Meanwhile, a coupled model for solid deformation and gas leak flow can be applied to the problems of gas leak flow including mining engineering, gas drainage engineering and mining safety engineering in particular the prediction of the safe range using protective layer mining where coal and gas outbursts can efficiently be prevented. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Thermal decomposition of NH4-analcime     

A.Yu. Likhacheva  S. A. Veniaminov  E. A. Paukshtis 《Physics and Chemistry of Minerals》2004,31(5):306-312

The thermal decomposition of ammonium-exchanged natural analcime is characterized by gas chromatography, IR spectroscopy and X-ray diffraction. The de-ammoniation and dehydroxylation proceed in parallel throughout the decomposition, which evidences the instability of the protonated analcime framework. The mechanism of degassing of NH₄-analcime changes throughout its decomposition. At the initial step, the mechanism of de-ammoniation consists in thermal dissociation of NH₄⁺ molecule onto NH₃ and proton (framework OH group) and diffusion of NH₃ out of the structure. Subsequent decomposition and removal of the OH groups lead to a progressive loss of crystallinity. At this step, an apparent activation energy for NH₃ desorption is estimated to be 145(±13) kJ mol^–1. This value is within the upper limit of the activation energy characteristic for the NH₃ desorption from proton centres in large-pore zeolites. At the final step, the adsorption of NH₃ and protons onto the defect centres in the amorphosed aluminosilicate framework results in a significant increase of an apparent activation energy for the de-ammoniation and dehydroxylation up to 270(±20) kJ mol^–1.  相似文献   

Application of AVO Analysis to Seismic Data for Detection of Gas below Methane Hydrate Stability Zone in Nankai Trough Area     

Masami Hato    Takao Inamori    Alfian Bahar  Toshifumi Matsuoka 《Resource Geology》2004,54(1):105-113

Abstract. For the purpose of development of methane hydrate, occurring in the deep marine subsurface, as a resource, the most important issue is to understand the methane hydrate system (generation, migration and accumulation) as well as to delineate the methane hydrate reservoir properties. We have applied the Amplitude Versus Offset (AVO) analysis to the seismic data acquired in the Nankai Trough, offshore Japan, in order to confirm the occurrence of gas just below the methane hydrate-bearing zone, assuming that gas will show a so-called Class-3 AVO response. Knowledge of the amount and occurrence of gas in the sediment below methane hydrate-bearing zone is one of the keys to understand the methane hydrate system.
We have utilized the qualitative analysis of AVO methodology to delineate how gas is located below the BSR, which is thought to be the reflection event from the interface between the methane hydrate-bearing zone and the underlying gas-bearing zone. In the region of MITI Nankai Trough Well PSW-3, we observe two BSRs separated by 25 ms. After AVO modeling using well data, we applied AVO attribute analysis and attribute crossplot analysis to the seismic data. Finally we applied an offset-amplitude analysis to CMP gather data at specific locations to confirm the results of AVO attribute analysis. The AVO analysis shows that there is very little gas located in the underlying sediment below methane hydrate-bearing zone. This result supports the fact that we could not obtain any clear evidence of gas occurrence just below the methane hydrate-bearing zone in the Nankai Trough well drilling.  相似文献   

Subsurface Occurrence of Natural Gas Hydrate in the Nankai Trough Area: Implication for Gas Hydrate Concentration   总被引：2，自引：0，他引：2  

Takashi Uchida    Hailong Lu  Hitoshi Tomaru 《Resource Geology》2004,54(1):35-44

Abstract. The Nankai Trough runs along the Japanese Islands, where extensive BSRs have been recognized in its forearc basins. High resolution seismic surveys and site-survey wells undertaken by the MITI have revealed the gas hydrate distribution at a depth of about 290 mbsf. The MITI Nankai Trough wells were drilled in late 1999 and early 2000. The highlights were successful retrievals of abundant gas hydrate-bearing cores in a variety of sediments from the main hole and the post survey well-2, keeping the cored gas hydrate stable, and the obtaining of continuous well log data in the gas hydrate-dominant intervals from the main hole, the post survey well-1 and the post survey well-3. Gas-hydrate dominant layers were identified at the depth interval from 205 to 268 mbsf. Pore-space hydrate, very small in size, was recognized mostly filling intergranular pores of sandy sediments. Anomalous chloride contents in extracted pore water, core temperature depression, core observations as well as visible gas hydrates confirmed the presence of pore-space hydrates within moderate to thick sand layers. Gas hydrate-bearing sandy strata typically were 10 cm to a meter thick with porosities of about 40 %. Gas hydrate saturations in most hydrate-dominant layers were quite high, up to 90 % pore saturation.
All the gas hydrate-bearing cores were subjected to X-ray CT imagery measurements for observation of undisturbed sedimentary textures and gas-hydrate occurrences before being subjected to other analyses, such as (1) petrophysical properties, (2) biostratigraphy, (3) geochemistry, (4) microbiology and (5) gas hydrate characteristics.  相似文献   

Origin of Natural Gas in Kekeya Field, Tarim Basin, China     

HouDujie XiaoZhongyao TangYoujun ZhuJunzhang LiXianqing 《中国地质大学学报(英文版)》2004,15(1):91-98

This paper is mainly concentrated on the geochemical characteristics and origin of gas of Kekeya field in the Tarim basin, NW China. This study shows that Permian mudstone is the main source rock of oil and gas. Based on the carbon isotopes of C1--C4, the carbon isotope of gas in Kekeya field is a little heavier than that in the typical marine-derived gas. The relationship between carbon isotopes of methane and ethane is coincident with Faber equation of gas derived from organic matter Ⅰ/Ⅱ. The majority of gas maturity is estimated, based on the formula, at 1.8%-2.2% besides K2 and K18 wells. In addition, the gas derived from 0.9%-1.2% Ro source rocks may also bemixture. ^40Ar/^36Ar and ^3He/^4He ratios from the gas samples also support the mixing process. Moreover, the gas in this region is mainly generated from more mature source rocks although the low mature gas exists.  相似文献   

Parameterization of the Absorption of the H_2O Continuum,CO_2,O_2,and Other Trace Gases in the Fu-Liou Solar Radiation Program     

张凤  曾庆存  K.N.LIOU 《大气科学进展》2005,(4)

The absorption properties of the water vapor continuum and a number of weak bands for H2O, O2, CO2, CO, N2O, CH4, and O3 in the solar spectrum are incorporated into the Fu-Liou radiation parameterization program by using the correlated k-distribution method (CKD) for the sorting of absorption lines. The overlap absorption of the H2O lines and the H2O continuum (2500-14500 cm-1) are treated by taking the two gases as a single-mixture gas in transmittance calculations. Furthermore, in order to optimize the computation efforts, CO2 and CH4 in the spectral region 2850-5250 cm-1 are taken as a new single-mixture gas as well. For overlap involving other absorption lines in the Fu-Liou spectral bands, the authors adopt the multiplication rule for transmittance computations under which the absorption spectra for two gases are assumed to be uncorrelated. Compared to the line-by-line (LBL) computation, it is shown that the errors in fluxes introduced by these two approaches within the context of the CKD method are small and less than 0.48% for the H2O line and continuum in the 2500-14500 cm-1 solar spectral region, -1% for H2O (line) H2O (continuum) CO2 CH4 in the spectral region 2850-5250 cm-1, and -1.5% for H2O (line) H2O (continuum) O2 in the 7700-14500 cm-1 spectral region. Analysis also demonstrates that the multiplication rule over a spectral interval as wide as 6800 cm-1 can produce acceptable errors with a maximum percentage value of about 2% in reference to the LBL calculation. Addition of the preceding gases increases the absorption of solar radiation under all sky conditions. For clear sky, the increase in instantaneous solar absorption is about 9%-13% (~12 W m~2) among which the H2O continuum produces the largest increase, while the contributions from O2 and CO2 rank second and third, respectively. In cloudy sky, the addition of absorption amounts to about 6-9 W m-2. The new, improved program with the incorporation of the preceding gases produces a smaller solar absorption in clouds due to the reduced solar flux reaching the cloud top.  相似文献