塔河地区石炭系盐体对地震参数及成像精度的影响

为探讨塔里木盆地塔河地区盐体下伏地层的影响．选择了一块具有代表性的区块，从速度、振幅、频率、偏移等方面进行了分析．首先对该区块的地震资料进行了重新处理：然后对DMO叠加速度以及炮域波动方程和克希霍夫叠前深度偏移剖面进行了对比分析；最后提取了下伏地层地震反射波的振幅和频率．探讨了盐体对地震波运动学和动力学参数的影响。结果表明．盐体对下伏地层的成像精度以及地震波的振幅和频率影响不大。     

中拐凸起石炭系火山岩储层预测

准噶尔盆地中拐凸起石炭系火山岩历经近40年的油气勘探未发现规模油气藏,问题的关键是未能有效预测火山岩储层发育带。为此,融合多种技术,在地震资料精细处理解释的基础上,准确预测了该区火山岩储层发育范围;通过地震属性、相关分析刻画火山岩有利储层平面展布规模;利用地震相特征刻画火山岩各类型圈闭;结合地震反演技术,确定火山岩有利储层的纵向规模。在预测结果指导下完钻的探井在石炭系均获得了高产工业油流。     

湘中地区下石炭统邵东组沉积相及海侵研究

湘中邵东组主要由细碎屑岩组成。研究表明邵东组是在滨外泥质陆棚沉积环境中形成的,沉积相主要有滨岸砂坝、滨外泥质陆棚及滨外碳酸盐陆棚。在邵东组占主要地位的滨外泥质陆棚相沉积,属于海侵沉积。因此邵东组及其底部的海侵与Johnson(1982)所提出的石炭纪底部全球性海侵事件一致,据此可认为邵东组形成时代可能仍属早石炭世早期。     

云南老厂银铅锌矿区火山岩特征

根据云南老厂火山岩的岩石学、岩石化学成分特征,可将下石炭统火山岩划分为5层、4旋回、4相、3个相组。其中:C_1～C_1~3为岛弧型玄武岩系列,C_1~4和次火山岩为大陆板块边沿裂谷碱性玄武岩系列,C_1~3为C_1~2钠质粗面质岩浆与C_1~4碱性玄武岩浆混合作用的产物。     

塔北隆起井下巴楚组及东河砂岩段的时代

通过塔北隆起井下巴楚组与地面巴楚组建立对比关系，认为井下巴楚组三层序的时代为早石炭世杜内期，相当于地面巴楚组上段至卡拉沙依组全部和小海子组底部，而地面巴楚组时代为早石炭世杜内期早期；东河砂岩段应归属上泥盆统。     

DIAGENETIC EVOLUTION OF INCISED CHANNEL SANDSTONES: IMPLICATIONS FOR RESERVOIR CHARACTERISATION OF THE LOWER CARBONIFEROUS MARAR FORMATION, GHADAMES BASIN, WESTERN LIBYA

This paper assesses the diagenetic history of potential fluvial hydrocarbon reservoir rocks deposited within incised valley systems of the Lower Carboniferous Marar Formation in western Libya. Outcrop data were collected in the Tinedhan Anticline, located at the southern margin of the Ghadames Basin. Four discrete intervals with channelized sandstones were identified in a section dominated by alternating offshore mudstones and shallow-marine clastics. The incised channels were cut during major sea-level lowstands, and filled by fluvial sandstone packages up to 50 m thick. Fifty-eight samples from four different localities, representing three lowstand systems tracts, were analysed to obtain a statistically meaningful mineralogical and compositional dataset. In addition to burial compaction, three main diagenetic events influenced the reservoir quality of the sandstones. Firstly, early eodiagenesis involved kaolinitization of plagioclase grains. This began before subsequent calcite cementation, probably as a result of flushing by meteoric pore-waters. The deformation of kaolinite during later compaction resulted in the formation of pseudomatrix which further reduced porosity and permeability. Kaolinite is commonly transformed to illite at temperatures above 140°C in the presence of K-feldspar. Although K-feldspar was recorded in the samples, no illite was observed, suggesting that the Lower Carboniferous strata in the study area were not buried in excess of approximately 3.5 km. The second diagenetic phase was the precipitation of calcite cement, present either dispersed throughout the sandbodies or as concretions up to 2 m across, in both cases reducing reservoir quality. The high intergranular volumes (IGV) of calcite-cemented sandstones (ranging between 35% and 40%) suggest that cementation occurred at burial depths of <500 m. Sandstones without calcite cement have lower IGV of between 17% and 25% as a result of mechanical and chemical compaction. Stable C and O isotope analysis of the calcite cement also supports precipitation at shallow burial depths, indicating a meteoric pore-water source for the calcite. The third and final diagenetic stage was partial chloritisation of kaolinite during meso-diagenesis. The elevated temperatures required for this transformation indicate burial to a minimum depth of approximately 2.5 km, which is consistent with the compaction data. Despite these diagenetic effects, the fluvial sandstones have an average porosity of 12%, with a range from 0.5% up to 25%. Permeability measurements on four sandstone samples indicate that the development of pseudomatrix did not reduce permeability significantly.     

一种加速勘探开发的最佳模式——四川盆地大天池构造带石炭系气藏开发概念设计

气藏开发概念设计是在气田评价勘探中引入开发设计编制的一个新概念、新方式。以四川大天池构造带石炭系气藏开发概念设计为例，详细地介绍了如何从建立地质模型入手，进行包括气藏地质研究、开发方案编制、钻采工程设计、地面建设工程设计等内容的气藏开发概念设计；以详细的资料数据反映了该概念设计在大天池构造带开发前期建设中取得的经济效益及这种“模式”的应用推广情况。开发概念设计的及早编制和实施，加强了开发与勘探的早期衔接，加快了勘探开发进程，节约了大量资金。     

论川东苟家场构造带天然气勘探

川东苟家场构造带石炭系天敢勘探累遭失利。分析钻探及探井测试资料，认为苟家场构造天然气充满程度不同，原因在于；构造两翼倾轴逆断层封闭性差，石炭系及上覆盖层破碎严重南端已缺失石炭系；氢此，认为家场构造的圈各地层－地垒背斜复合圈闭、志留系气源岩生成的天然气只能在狭２长的圈闭范围内由下向上，自北向南端多，聚集，因而控气范围有限，可能只在构造顶部有气。     

北淮阳带北缘石炭系碎屑岩地球化学特征及物源区构造环境

北淮阳构造带出露的石炭系为古生代唯一一套未变质或轻微变质的地层,其沉积记录可较好地反映物源区物质组成及构造环境。基于1∶5万区域地质调查工作,对采自北淮阳构造带北缘三仙山地区的石炭系碎屑岩进行主量、微量及稀土元素分析,探讨石炭系物源区及构造环境。研究表明三仙山地区的石炭系有不同的物源区,杨山组和道人冲组物源区可能主要为扬子陆块或再旋回造山带,胡油坊组物源区可能为扬子陆块与华北陆块。     

柴达木盆地石炭系烃源岩评价

在野外地质调查基础上,系统分析了柴达木盆地石炭系烃源岩分布以及地球化学特征,并从有机质丰度、类型和成熟度方面对烃源岩进行了综合评价。研究认为:柴达木盆地石炭系烃源岩广泛分布在全盆地大部分地区。柴北缘烃源岩厚度大\,分布广,厚度中心主要位于欧龙布鲁克山一带,最大残余厚度达900 m;柴南缘厚度次之,沿盆地边缘呈带状展布,在格尔木-乌图美仁-甘森一带厚度在400~500 m之间,盆地西北及东南角厚度较小。石炭系主要发育暗色泥岩、碳酸盐岩和煤3种类型烃源岩。暗色泥岩有机质丰度均值为1.28%,有机质类型主要为Ⅲ型与Ⅱ₂型,处于成熟-高成熟阶段,为中等-好的烃源岩;碳酸盐岩有机质丰度较低,平均值为0.37%,有机质类型为Ⅱ₁-Ⅱ₂型,综合评价为差烃源岩;石炭系煤岩则为良好的气源岩。总体而言,柴达木盆地石炭系分布广泛,具有较好的油气勘探远景。 