层裂

The determination of formation fracture pressure and the geometry of hydraulic fracture is critical for designing rational fracturing program, providing optimal operation pressure, avoiding interzonal crossflow caused by excessive fracture height, and better stimulating the reservoirs.

确定地层破裂压力和水力压裂裂缝延伸几何形态，对于设计合理的压裂方案、提供合理的压裂施工压力、避免压裂裂缝高度过高导致地层间的层间窜漏、更好地达到改善储层的目的至关重要。

This article that focuses on the systematic and in-depth research in the current primal problem about abnormal burst pressure reservoir depress burst pressure has procured following main fruits:1 It forms the method which could obtain massive vertical static state mechanics parameters.2 In a foundation of acquisition of rock mechanics parameters,apply bent lamella that as mechanical model along with characteristic of actual geologic characteristics to analysis curvature for anticlinal strcture, get homologous tectonic stress value throug relation between the curvature and stress and different principal curvature in anticlinal structure,consequently set up laminational stress model for anticline reservoir. The block lamination for existed fracturing date has formed method of setting up mechanical model of lamination terrestrial stress by abtaining the block tectonic stress coefficients which are got by complex utilization test, laboratory test and fracturing date playback.3 Analysesing the main reason which lead to high burst pressure by considering the characteristic of reservoir geology,reservoir,and rock mechanics and reservoir damage,etc.Establishing burst pressure quantitative prediction model which provide gist for depressing construction risk and optimizing construction craft under the condition of open hole completion ,gun-perforated completion and damaged reservoir.4 Provding theoretical basis for interpreting acidification pretreatment which could depress busrt pressure by finding the relation between the influencing factors and rock machanics parameters and analysing the factors that have effect on rock mechanics parameters. Expounding the mechanism of reaction of mixed monomineral and acid from the angle of microcosmic element, evaluating quantitatively acid sensilility of different kinds of mineral effectively, and determing the first-order reaction dynamical equation of each mineral.5 Revealing rock mechanics property chage as a result of acid flooding in different condition by sandstone traumata experiment in different temperatures which combined with rock mechanics triaxial stress experiment.6 Associating damage mechanics with sandstone acidizing, established sandstone damage mechanics model in the foundation of the recognition on the rock mechanics parametric variation which is caused by acid-rock reaction in both macroscopic view and microscopic view ,also demonstrated those processes and quantitative estimated the acid busrt pressure to direct the site operation.

本文针对目前异常破裂压力储层降低破裂压力的主要问题展开较为系统和深入的研究，取得了以下主要成果：1形成了利用测井资料，结合室内岩芯测试结果，获取静动岩石力学参数的相关性特征，从而获得纵向上大量静态力学参数的方法。2在获取了岩石力学参数的此基础上，利用弯曲薄板作为力学模型，结合区块实际地质特征对背斜构造进行曲率分析，通过曲率与应力的关系，利用背斜构造不同部位的主曲率求得相应的构造应力值，从而建立起背斜储层的分层应力模型；对已有压裂资料的区块分层，形成了综合利用测试、室内实验、压裂资料反演获得该区块构造应力系数，建立起分层地应力的力学模型的方法。3综合考虑储层地质、油藏、岩石力学特性和储层伤害等因素，分析造成高破裂压力的主要原因，综合利用岩石力学、弹性力学等知识，建立了裸眼完井、射孔完井条件下以及储层受到伤害后的储层破裂压力定量预测模型，为降低施工风险和优化施工工艺提供了依据。4完成了物性、岩性影响岩石力学参数的因素分析，找出了各影响因素和岩石力学参数之间的关系，为从机理上解释酸化预处理降低破裂压力提供了理论基础；从微观元素的角度阐述了单矿物与酸反应的机理；并在此基础上，有效评价了各种矿物的酸敏感性，定量确定了岩石中各矿物的一级反应动力学方程。5完成了不同温度下的酸液类型、酸液浓度、注酸量等一系列砂岩损伤实验，结合岩石力学三轴应力实验，系统揭示了在不同条件下注酸而引起的岩石力学性质变化。6将损伤力学与砂岩酸化相结合，在宏观、微观两个方面认识酸岩反应引起岩石力学参数变化基础上，建立了砂岩损伤力学模型，并对其进行验证，在此基础上定量计算酸化后的破裂压力，有效指导现场施工

The tuffaceous volcanic reservoir s of Xing'anling group in Hailaer Basin, Daqing Oilfield, includes andesite-rhyolite tuffaceous, andesite tuffaceous and trachy-rhyolite tuffaceous volcanic rocks.

针对这些特点，通过岩石水理特性实验和岩石力学特征研究，提出了以下解决措施：①凝灰质火山岩储层粘土含量高时，应提高压裂液的防膨胀性能，大排量施工，增加裂缝净压力；②碱性和偏碱性凝灰质储层，应研究使用低滤失压裂液，降低滤失量，同时提高压裂液的防膨胀性能；③凝灰质储层塑性较强时，应尽量提高施工排量。

Since the polymer bar material has a lower mechanical impedance than the concrete specimen, spalling can be produced in the concrete rod after the compressive wave in the concrete specimen is reflected back as a tension wave at the concrete/buffer bar interface.

由于波在粘弹性材料中的弥散效应，吸收杆中透射波形会发生变化，但三维有限元分析表明，在利用吸收杆上透射波确定混凝土层裂强度时弥散产生的影响可以忽略。

During the fracturing for low pressure and low permeability gas reservoirs, there are some main problems in conventional hydroxypropylguar - organic boron cross-linking system: Firstly, the water-lock damage to low pressure and low permeability gas formations by filter liquor; Secondly, the reason for alkali-sensitive damage in alkali-sensitive reservoirs is that conventional hydroxypropylguar - organic boron cross-linking fracturing fluids were cross-linked under alkaline environment, while the permeability of reservoirs is reduced greatly; Thirdly, the formation pressure is low, and the energy of flow back is not enough, at present, the main measure in oil fields is "injecting with liquid nitrogen", but this technique increased the cost of fracturing, making great troubles in operating, and leaving the liquid nitrogen also is a big problem.

在低压低渗透气藏的压裂改造过程中，常规羟丙基胍胶-有机硼交联压裂液体系存在的主要问题，一是压裂液滤液对低压低渗透气层造成的水锁损害；二是常规羟丙基胍胶-有机硼压裂液是在碱性条件下交联的，对碱敏性储层造成碱敏损害，降低储层渗流能力；三是地层压力低，压裂液返排能量不足，当前各油田采取的措施主要是&液氮伴注&技术，但是&液氮伴注&技术增加了压裂的费用，而且液氮存放也存在较大问题。

After unloading,both ends of the rod become free surface,which both play the role of stress unloading for the incident stress wave,and multiple spalls may occur.

加载端卸载后，杆处于两端自由面共同应力卸载作用下，可能出现多重层裂的现象。

SEM observation of the spalled surface of the alloy unveils statistically self similar pattern in the range between 10μm and 1000μm.

在一定的尺度范围（约为10～1000μm）内，不同放大倍数下的层裂表面可以看到统计自相似的网络状图案。

Noticeably, the spalled surface is formed by the coalescence of roughly parallel microcracks.

层裂表面是由大量相互平行的微裂纹级串连接形成的。

The crack occured in silica brick generally includes surface crack and layer crack.

硅砖中裂纹包括表面裂纹和层裂。

Using a gas gun,a set of plate impact experiments were performed for 20 steel by measuring the rear free-surface velocity profiles with a velocity interferometer system for any reflector.

采用轻气炮加载技术和激光速度干涉测速技术相结合，对不同拉伸应变率条件下20钢的层裂特性进行了实验研究。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。