张掖市平山湖地区煤岩层物性规律研究与测井方法应用

通过对平山湖地区11口井的测井资料进行分析,初步掌握了该区含煤岩层的地球物理特性及其在视电阻率、密度、自然伽马、声波时差、自然电位等测井曲线上的响应特征。总结出一套适合该地区的测井方法,如各种测井参数的数据计算方法与曲线处理技巧,为该类地区使用TYSC-3Q测井仪器进行测井提供了参考依据。针对该地区煤层具有中高阻、低密度、低放射性、高时差、弱自然电位的物性特征,以多个实例介绍了煤层在不同测井参数曲线上的识别方法及定量解释原则。     

浅议测井曲线在松树头煤矿含水层解释中的应用

以松树头煤矿水文地质勘查为例,介绍了测井曲线在含水层解释中的应用。实例表明,自然伽马、自然电位和视电阻率三种曲线对含水层具有明显的异常反应,在含水层中,前二种曲线表现为负异常,后者表现为正异常;对于隔水层,前二种曲线则表现为正异常,而视电阻率表现为负异常。根据测井解释成果与钻孔消耗量、岩心及抽水试验资料相互印证,解释松树头煤矿ZK5-2钻孔368.30～406.42m段,从上到下依次为含水层、隔水层、含水层、隔水层四段。另外,从实例应用的三种曲线可知,视电阻率曲线对于岩石粒度及含水层具有明显的响应特征,极差高达117Ω.m。     

测井方法在湖南测水煤系中的应用

测水煤系是湖南分布较广、储量丰富的含煤地层之一。对于结构简单,灰份较低的煤层,可以通过异常明显的自然伽马低异常与伽马伽马高异常加以判别。但在结构复杂、挤压破坏强烈、薄煤分层、夹矸与顶底围岩炭化程度高、煤与围岩及夹矸物性差异小等情况下,仅靠自然伽马与伽马伽马等常规测井方法难以满足测井质量验收标准。以浆江勘探区3909孔、3503孔及金竹山矿区7403孔为例,利用伽马伽马短源距、三侧向、声速及密度等测井方法,结合常规自然伽马与伽马伽马测井,较好地解决了复杂结构煤层的定性、定厚问题,取得了较好的地质效果。     

Quantification of uplift in the Carnarvon Basin based on interval velocities

Sonic velocities in the Toolonga Calcilutite (Upper Cretaceous), the Gearle Siltstone and Haycock Marl (mid‐Cretaceous), and the Muderong Shale (Lower Cretaceous) were each used to independently quantify apparent uplift (height above maximum burial depth) in the Carnarvon Basin. Apparent uplift is given by the difference in depth between the present‐day velocity‐depth trend for a unit in a particular well and the reference trend (unaffected by uplift) of the unit. Apparent uplift results derived from the Toolonga Calcilutite, Gearle Siltstone and Muderong Shale are statistically similar. The consistency of results from carbonate and clastic units suggests that, at the formation and regional scale, overcompaction (i.e. anomalously high interval velocity) in these three units reflects previously greater burial depth, rather than sedimentological and/or diagenetic processes, and validates the use of lithologies other than shale in maximum burial‐depth studies. The proposed magnitudes of apparent uplift are greatest along some of the main structural highs of the Carnarvon Basin. Apparent uplift of approximately 800 m was determined along the Legendre Trend, and along the Barrow Arch. In excess of 900 m of apparent uplift was determined on the Bambra Anticline. The consistency of results from units of Early to Late Cretaceous age suggests that uplift must have post‐dated the youngest (Late Cretaceous) unit analysed.     

Shallow geothermal regime in the Perth Metropolitan Area

Exploration of Perth's geothermal potential has been performed by the Western Australian Geothermal Centre of Excellence (WAGCoE). Detailed vertical temperature and gamma ray logging of 17 Western Australia Department of Water's (DoW) Artesian Monitoring (AM) wells was completed throughout the Perth Metropolitan Area (PMA). In addition, temperature logs from 53 DoW AM wells measured in the 1980s were digitised into LAS format. The logged data are available in the WAGCoE Data Catalogue.

Analysis of the gamma ray logs yielded the first estimates of radiogenic heat production in Perth Basin formations. Values by formation ranged between 0.24 and 1.065 μW m^?3. The temperature logs provide a picture of true formation temperatures within shallow sediments in the Perth Basin. A three-dimensional model of the temperature distribution was used to produce maps of temperature at depth and on the top of the Yarragadee aquifer.

The temperature data were interpreted with a one-dimensional conductive heat model. Significant differences between the model and the observations was indicative of heat moving via non-conductive mechanisms, such as advection or convection. Evidence of non-conductive or advective heat flow is demonstrated in most formations in the region, with significant effects in the aquifers. Average conductive geothermal gradients range from 13°C km^?1 to 39°C km^?1, with sandstone formations exhibiting average gradients of approximately 25°C km^?1, while insulating silt/shale formations show higher average gradients of over 30°C km^?1.

To produce preliminary heat flow estimates, temperature gradients were combined with thermal conductivities measured elsewhere. The geometric mean heat flow estimates range between 64 mW m^?2 to 91 mW m^?2, with the standard deviation of the arithmetic mean heat flow ranging between 15 and 23 mW m^?2.

The study characterises the shallow temperature regime in the Perth Metropolitan Area, which is of direct relevance towards developing commercial geothermal projects.     

测井曲线在杭东勘查区煤炭普查煤岩层对比中的应用

杭东普查区煤层产状平缓,构造简单,但由于含煤地层为陆相沉积,煤层层数多、厚度、间距变化大,沉积岩相变化快、大范围内缺乏稳定的对比标志层,因此煤岩层对比是本区勘查需要重点解决的难题。通过对比杭东普查区与邻区200余孔的测井资料,分析煤岩层在各种测井曲线的异常特征与异常组合规律,确定了对煤岩层对比有重大意义的标志层,如延长组与上覆延安组的典型视电阻率异常分界;延安组在高视电阻率曲线上的“树杆”状凸起特征;安定组视电阻率曲线近直线的低值形态;4-1煤在视电阻率曲线上呈现出的“斜坡”状或“刀”状高异常,以及在自然伽玛曲线上的“凹坑”特征;侏罗系中统直罗组的高伽马异常,等等。这些典型特征保证了该区煤岩层对比可靠性,为提交优质地质勘查报告发挥了重要作用。     

陕北三叠纪煤田蟠龙至高家屯勘查区5号煤层顶板工程地质特征

研究区5号煤层位于三叠系瓦窑堡组第四段上部,煤层直接顶以泥岩、砂质泥岩为主,老顶以粉砂岩、泥岩和细粒砂岩为主,从岩性分布来看,总体呈现出向上变粗的沉积层序,对应的顶板类型为下软上硬型.进一步分析其岩石力学性质、测井曲线与岩体质量指标,参考岩层厚度、层理及裂隙等,综合分析确定该区5号煤层顶板属基本稳定型.该研究为煤矿的安全生产提供了技术支持.     

海拉尔油田乌东区块螺旋井壁成因分析与解决方法

自海拉尔油田实施钻井提速以来,部分井出现螺旋井壁现象,对完井电测曲线造成一定影响,影响测井解释的共151口井,比例达15.60%。螺旋井壁现象在乌东区块尤为明显,仅乌东区块发生明显螺旋井达到36口,占乌东区块全部钻井的28.8%。从地质、工程等角度阐述了形成螺旋井的原因,并提出了解决思路与技术措施。2012年下半年在乌尔逊凹陷2口井试验螺旋井壁预防及解决方法,获得了较好的效果,未再大面积出现螺旋井壁现象。     

建立磁化率快速预测白马钒钛磁铁矿含量模型

根据白马钒钛磁铁矿区试验钻孔井壁岩矿石磁化率与钒钛磁铁矿含量的关系,矿区岩矿石磁化率与钒钛磁铁矿含量的相关性,建立了磁化率与钒钛磁铁矿含量的回归方程。通过此方程的应用可以快速判断井壁岩矿体的钒钛磁铁矿含量,指导采样布设。     

地球物理测井在天然气水合物勘探中的应用

天然气水合物是一种潜在的巨大能源。美国、日本、俄罗斯等发达国家在该领域已经进行了大量的研究工作，试图从各个角度去探测天然气水合物的存在并评价其蕴藏量。地球物理测井在天然气水合物探测与储量评价领域发挥了重要作用并且随着以勘探天然气水合物为目的的钻井的增多，日益受到重视。基于国内在该领域研究较少的现状，综述了国外地球物理测井技术在天然气水合物勘探中的应用，详细介绍了常规测井方法定性识别和定量评价天然气水合物储层的孔隙度、饱和度方法和技术，基于含天然气水合物储层的碳氧比能谱测井解释模型以及成像测井在含天然气水合物井段的测井响应。并在此基础上分析了我国在该领域的研究思路。