碎屑岩地层压实规律及其在古构造恢复中的应用

碎屑岩地层压实作用在不同地质背景和不同盆地演化阶段具有完全不同的规律,一直以来都是油气勘探工作的重点和难点。国内外研究者为推动碎屑岩压实规律定量研究做了大量工作,但其研究成果往往具有地域性和局限性。在国内外相关领域研究成果基础上,从地层压实作用影响因素、压实规律表征方法、正常压实曲线构建方案、利用地层压实规律反演盆地古构造特征和误差定量评价等5个方面进行了系统调研和探讨。结果表明:碎屑岩地层压实规律研究及其在古构造恢复方面的应用仍处于初级阶段,根据研究区地质特征选取适宜的地层压实规律表征方法和误差评价方法是碎屑岩地层压实规律研究和应用的关键。

地层压实恢复的定量计算

在地层压实研究的基础上，阐述了利用压实曲线定量恢复地层原始厚度和原始孔隙度的方法，对计算过程中各种问题的处理以及参数的选取和计算进行了讨论，利用这一方法，可以定量描述地层压实过程以及构造演化史和烃源岩埋藏史。

一种新型地层压实监测仪现场应用实例

随着原油的不断采出，孔隙压力减小，地怪有时会压缩，从而导致套管损坏、地表下沉，测此种现象的重要按需分配技术涉及定期监测置入地层或套和寂的放射性标记间距。基柯用来估算产层压缩率，预测未来地层压实、地表下沉以及原油产量。为此，研制际层压实监没暹ＣＭＩ）５０７个层段平均测量精度达１．１５ｍｍ。

储层压实引起套管失效的机理研究

套管失效问题是一个世界性的难题 ,严重影响了石油工业的经济效益。其典型失效形式包括套管腐蚀、径向变形、剪断等 ,失效原因包括油井水腐蚀、层间滑动引起的剪切作用和非均匀地应力作用等 ,其中油藏压实是诱发失效原因的主要因素之一。为了弄清油藏压实对套管损坏的影响规律 ,在对地层发生压实的原因、机理进行了研究的基础上 ,对地层压实引起的套管失效机理进行了详细分析 ,提出了预防或减少压实地层套管失效的对策 ,即提高套管设计水平 ,确定合理井身结构 ,维持合理注水压力 ,采用厚壁套管等。

碎屑岩层的分层去压实校正方法

由于同一探井或同一地区中的不同层段的碎屑岩层在岩性和埋藏的动力学过程等方面存在差异,根据观测数据建立的统一的孔隙度-深度函数并不能真实地反映出各岩层的压实历史。同种类的沉积岩石的初始孔隙度值可能相差不大,它们主要受碎屑颗粒大小和沉积相影响,但是其压实过程可能会存在较大的差异。为了提高碎屑岩层去压实校正的精度,该文提出一种分层去压实校正方法。首先,可以按岩性和地层时代等划分"地层压实单元",然后,分别建立各"地层压实单元"的孔隙度-深度函数。不同的"地层压实单元"可以分别采用能反映它们的压实过程的压实模型,并通过实验方法确定各"地层压实单元"的初始孔隙度。在此基础上再根据"地层骨架厚度不变"原理进行去压实校正。

地层压力预测方法评价及发展趋势

将现有的各种地层压力预测方法按照预测原理进行分类,总结并归纳了各类方法的特点和应用条件,在此基础上分析了已有的地层压力预测方法在理论和应用实践上的缺陷,并对地层压力总体预测方法的发展趋势作了预测。

菲律蒲斯石油公司为EKOFISK油田新增一套注水系统

由于EKOFISK油田地层压实而导致海底继续下陷,挪威菲律蒲斯石抽公司决定扩大其2/4K平台的现有注水计划,使其注水能力由80,000m^3/d增至128,000m^3/d以上。此项计划被认为是减轻海底进一步下陷及大幅度提高产油量的最有效方法。由于急需注水,而固定平台上又没有空间以及平台改造时间长,耗资大,菲律蒲斯公司决定在一艘钻井船上安装注水设施。

A formation pressure prediction method based on tectonic overpressure

Traditional formation pressure prediction methods all are based on the formation undercompaction mechanism and the prediction results are obviously low when predicting abnormally high pressure caused by compressional structure overpressure.To eliminate this problem,we propose a new formation pressure prediction method considering compressional structure overpressure as the dominant factor causing abnormally high pressure.First,we establish a model for predicting maximum principal stress,this virtual maximum principal stress is calculated by a double stress field analysis.Then we predict the formation pressure by fitting the maximum principal stress with formation pressure. The real maximum principal stress can be determined by caculating the sum of the virtual maximum principal stresses.Practical application to real data from the A1 and A2 wells in the A gas field shows that this new method has higher accuracy than the traditional equivalent depth method.

声波测井的时差和延迟

声波仪器中多个接收器记录的纵波首波初至时间可用来估算地层时差。在井眼周围变化的情况下，例如蚀变层或污染带(由于钻井的结果)，井眼折射波至能穿过井壁几英寸到几英尺，所以时间被延迟。用地面地震测量中已广泛用于解释折射波至的截距时间法来计算延迟。计算出来的延迟可用来确定蚀变层范围。但是，计算延迟需要精确选取折射波至的真初至波时间。然后用选取的时问来获得时差曲线和延迟曲线。本文描述了选取真初至波时间以及计算延迟、对差曲线的方法。选取过程有两个步骤：第一步；使用自动程序选取特定相位的波至时间，在信噪比较好的情况下，跟踪选取真初至波。使用的算法是以人工智能方法为基础，以形状和连续为准则，监视某个特殊波从一个径迹到下一个径迹，从一次激发到下一次激发。第二步；使用单侧脉；中反褶积后恢复真初至波。本文还列举了在碳酸盐储层及砂岩储层中记录的声波数据，从中导出的时差和延迟曲线。这种延迟和井眼相一致并与岩性有关。第一个现场实例为白云岩和石灰岩组成的碳酸盐储层。该储层中延迟时间的增加与裂缝带有关。第二个现场实例为泥岩和砂岩组成的储层。延迟时间在泥岩层中增加。砂岩多孔层中延迟时问的增加与疏松砂层的存在有关。用与泥岩指数、地层压实系数相关的声波参数(延迟和泊松比)预测疏松地层。

Determining areas in an inclined coal seam floor prone to water-inrush by micro-seismic monitoring

The failure depth of the coal seam floor is one important consideration that must be kept in mind when mining is carried out above a confined aquifer.Determining the floor failure depth is the essential precondition for predicting the water-resisting ability of the floor.We have used a high-precision microseismic monitoring technique to overcome the limited amount of data available from field measurements. The failure depth of a coal seam floor,especially an inclined coal seam floor,may be more accurately estimated by monitoring the continuous,dynamic failure of the floor.The monitoring results indicate the failure depth of the coal seam floor near the workface conveyance roadway（the lower crossheading） is deeper and that the failure range is wider here compared to the coal seam floor near the return airway（the upper crossheading）.The results of micro-seismic monitoring show that the dangerous area for water-inrush from the coal seam floor may be identified.This provides an important field measurement that helps ensure safe and highly efficient mining of the inclined coal seam above the confined aquifer at the Taoyuan Coal Mine.

Technology of back stoping from level floors in gateway and pillar mining areas of extra-thick seams

According to the special requirements of secondary mining of resources in gateway-and-pillar goal in extra-thick seams of Shanxi, this paper presents a technical proposal of back stoping from level floors. Numerical simulation and theoretical analysis are ccsed to investigate the compaction characteristics of cavities under stress as well as an appropriate mining height of the primary-mining layer based on dif- ferent mining widths and pillar widths. For Yangjian coal mine, the mining thickness of the first seam during back stoping from level floor is determined to be 3 m, which meets the relevant requirements. Gateway-and-pillar goaf of a single layer has a range of influence of 9 m vertically. If gateway-and-pillar goaf occurs both in 9-1 and 9-5 layers, the range is extended to within 11.2 m. When the mining width of a gateway is less than 2 m or larger than 5 m, the gateway-and-pillar goal in the upper layer of the primary-mining seam can be filled in and compacted after stoping. When the working face is 2 m away from the gateway and pillar before entering into it and after passing through it, the coal body under the gateway and pillar is subjected to relatively high stress. During mining of the upper layer, moreover, the working face should interlock the goaf in primary-mining layer for 20 m.

Study on Properties of Anti-Gas Channeling Lightweight Temperature-Resistant Latex Slurry

There is low formation pressure coefficient and high formation temperature in ludong-wucaiwan area. Gas cut and gas channeling happen seriously during oil and gas well cementing. The existing anti-migration additive has only effects on single trait, so it is difficult to meet cementing requirement. According to this situation we could use latex slurry to anti-gas channeling. We have synthesised a set of anti-gas channeling lightweight temperature-resistant latex slurry and formed a new channeling preventing latex slurry through plenty of previous laboratory experiments. Finally the performance of latex slurry on temperature-resistant, anti-gas channeling and the anti-gas channeling of cement paste are studied. The experimental results show that this latex system has strong temperature-resistant and anti-gas channeling, which completely meet the requirement of cementing in this area.

The Drainage Exchange of Stormwater Potential in Flat Area Problems

Groundwater as an alternative source still does not contribute to the water supply in area of Parit Raja because of the limitation of water availability in the ground. This lacking of groundwater could be caused by the circumstance that the top layer of soil is dominated by compacted clay around 2 meters in which its permeability is small, so the water is difficult to infiltrate the ground. The recharge well technique was designed based on the flat area problems, layer of real condition, flow water table and low infiltration rate. Resistivity soundings were made at existing wells to assess the subsurface layers. Beside that, the past records on floods event, sub surface and surface studies were collected around study area as a preliminary studies. It was presented that the study area promised good prospects to increase the capability of groundwater and contribute to the drainage system by reducing the volume of rainfall runoff using the recharge well technique.