古河道解释及在油气勘探中的意义   总被引：4，自引：1，他引：4  

宁松华  张厚福 《沉积学报》1997,15(3):33-36

古河道沉积是一种比较特殊的沉积体，它在地震剖面上的表现形态多种多样，且一般不易识别，必须经过仔细观察和认真分析才能发现。河道有其独特的沉积方式，能形成多种不同类型的沉积砂体，而这些砂体如果接近油源，则有可能成为高产油气藏。我国已在许多油田发现了河道沉积体，其中有些河道砂岩体已打井并获高产油气流。因而如何在地震剖面上识别古河道，一直是地质人员所关注的重要问题。本文通过我国西部某盆地Ｔ凹陷古河道的解释实例，阐明了古河道的沉积特点和在地震剖面上的地震相及反射特征。  相似文献   

东坪金矿地球物理和地球化学找矿模式     

赵志龙  耿中秋 《黄金地质》1997,(2)

东坪金矿产于华力西期偏碱性杂岩体内接触带中，成矿与地层、构造、岩浆演化密切相关，为石英脉（网脉）、钾长石化蚀变岩型金矿床。通过大量的物化探资料分析研究，建立了物化探综合找矿模式。  相似文献   

构造圈闭有效性的数学判别     

温祥泉  丛金山 《海相油气地质》1997,2(3):40-44

构造圈闭有效性的数学判别，是将以往的定性分析发展为定量分析。本方法以同沉积原理为基础，用数学方法分析的构造顶部与翼部的地层厚度变化关系，计算出了不同地质历史时期的构造生长指数，绘制地质年代与构造生长指数的关系曲线，进而结合分轩模拟结果分析构造圈闭的有效性。给出了本方法在海相碳酸岩地区某构造圈闭的应用实例。用此方法进行构造圈评价可使油气探更逼近目标，减少预探风险，提高钻井成功率。  相似文献   

煤矿软岩变形力学机制与支护对策   总被引：6，自引：0，他引：6  

何满朝 《水文地质工程地质》1997,24(2):12-16

近年来作者运用现代工程地质学和近代力理论研究巷道的稳定性控制，总结，提出了软岩的定义，煤矿软岩的特点，煤矿软岩的基本力学属性，软岩巷道变形力学机制和软岩巷道支护的对策等一系列新理论，通过对１２软岩煤矿的支护实践证明该理论体系软岩巷道支护是行之有效的。  相似文献   

论油气的应力圈闭   总被引：1，自引：0，他引：1  

祁林 《四川地质学报》1997,(1)

很多事例表明，含油气盆地或含油气地层及其中的一切物质（包括油、气、水等）的运动，都主要受地应力驱动的控制。在地应力作用下，含油气盆地或含油气地层中分散的油气，通过岩石介质形变产生的应力梯度（所造成的压力差异）的变化，而实现的“应力聚集”作用。在这种作用下的油气运移聚集和圈闭成藏，即是“应力圈闭”作用的结果。  相似文献   

Ant composition and activity patterns as determined by pitfall trapping and other methods in three habitats in the semi-arid Karoo     

P. A. Lindsey  J. D. Skinner 《Journal of Arid Environments》2001,48(4):551

The diversity and abundance of epigaeic ant species were determined across three habitats (riverine areas, gently sloping grassland areas and steep slope areas) in summer (November–December) and winter (May–June) of 1998 at Tussen die Riviere Nature Reserve in the Karoo, to determine temporal and spatial variations in the availability of potential prey species of the aardvark (Orycteropus afer). Pitfall trapping, dig sampling and quadrat sampling were used to ensure as complete a sampling effort as possible. Forty-five ant species of five sub-families and 17 genera were recorded. The grassland habitat yielded the highest abundance and diversity, followed by the steep slope and riverine areas. Ant abundance and diversity were higher during summer than winter in all three habitats. Anoplolepis custodiens was the most abundant species in summer, whilst Monomorium albopilosum was the most abundant species in winter. Pitfall trapping was responsible for recording more species than dig sampling or quadrat sampling. No method recorded all of the species present.  相似文献   

Geologic risk, economic assessment, and optimal decision making of petroleum plays in the Bohaiwan Basin, northern China     

Gongyang Chen  Gongquan Li  Zezhong Wang 《Natural Resources Research》1997,6(4):329-337

A system of play (trap) assessment based on the analysis of geological characteristics of five different types of petroleum plays in the Bohaiwan Basin, northern China, is proposed. The system makes use of conditional probability, fuzzy logic, and Monte Carlo simulation to assess geologic risk for estimating the undiscovered petroleum resources in a region. Combining the estimates of undiscovered resources with the subsequent economic evaluation of discovered resources by using techniques of optimization, the expected monetary value can be estimated to determine the overall benefits of an investment. A software program has been developed to carry out the calculations.  相似文献   

Bank-derived carbonate sediment transport and dissolution in the Hawaiian Archipelago     

Christopher L. Sabine  Fred T. Mackenzie 《Aquatic Geochemistry》1995,1(2):189-230

This investigation used two approaches to examine the flux of bank-derived carbonate particles and determine the potential influence of benthic carbonate particle dissolution on the carbon chemistry of the waters around the Hawaiian Archipelago. First, the particle flux near several representative carbonate banks in the Hawaiian Archipelago was measured and compared with the flux at a distal site (ALOHA) approximately 100 km north of Oahu, Hawaii. The results of four sediment trap deployments on three carbonate banks in the Hawaiian Archipelago demonstrate that the flux of bank-derived carbonate particles are consistently one to two orders of magnitude higher than the fluxes at the distal station. Furthermore, the mineralogy of the carbonate flux near the banks, which includes very soluble bank-derived aragonite and magnesian calcite particles, is distinctly different from that of the distal fluxes. Second, the chemistry of the waters at each bank station along the archipelago was characterized and compared with the chemistry of the distal waters to determine if differences in the particle flux were reflected in the carbon chemistry. Higher alkalinity and carbonate ion concentrations were observed around all of the banks studied. The saturation state of these waters suggests that the dissolution of some magnesian calcite and aragonite phases could explain the higher alkalinity values. Calculations suggest that the dissolution of benthically-derived aragonite and magnesian calcite may be an important component of the North Pacific alkalinity budget and a potential sink for anthropogenic CO₂.  相似文献   

塔里木盆地构造样式与构造圈闭类型特征分析     

何发岐  何海泉 《新疆地质》1995,(1)

依据塔里木盆地构造变形特征，可划分出压缩、伸展、走滑和反转四种构造样式。它们的发育特征控制了构造圈闭的形成和展布。据成因可将塔里木盆地构造圈闭划分为２类，５型，１５亚类。多期构造运动影响，多种构造样式的复杂组合，决定了塔里木盆地复式油气聚集带的形成。  相似文献   

二元混合体系的端元Sm-Nd模式年龄计算方法          下载免费PDF全文

杨晓松  胡家杰 《地质科学》1993,28(1):37-43

报道二元混合体系的端元Sm-Nd模式年龄的计算方法,即利用二元混合体系的Rb-Sr、Sm-Nd同位素分析结果,可以计算2个端元的Sm-Nd同位素组成,两端元在混源样品中的质量百分比,以及地壳残留时间。同时计算了广西花山复式花岗岩的端元模式年龄,结果显示该岩体的物质来源于2500Ma华南古陆壳和622Ma从亏损地幔分异出来的大洋地壳的混合物。  相似文献