沾化凹陷南斜坡油气运移条件及运移特征研究

油气运移的条件和油气运移的特征决定了油气藏的形成与分布。沾化凹陷南斜坡不整合面、断层以及各层系储集砂体的空间配置构成复杂的立体网络通道，决定了油气的运移，控制了油气分布。以断层为垂向运移通道的油气藏常在断层带附近多层叠置；以连通砂体为主要运移通道的油气藏常形成于距烃源层较近或相邻的层位；以不整合面作为运移通道往往可使油气长距离运移形成各种地层油气藏。沾化凹陷南斜坡的油气藏都是油气经过两种或多种输导层阶梯式运移而形成的。砂体、断层和不整合面组成的输导系统的末端和边缘是油气运移的重要指向区。     

Simulation-based sequential analysis of Markov switching stochastic volatility models

We propose a simulation-based algorithm for inference in stochastic volatility models with possible regime switching in which the regime state is governed by a first-order Markov process. Using auxiliary particle filters we developed a strategy to sequentially learn about states and parameters of the model. The methodology is tested against a synthetic time series and validated with a real financial time series: the IBOVESPA stock index (São Paulo Stock Exchange).     

Design of thermophoretic probe for precise particle sampling

We proposed a design methodology for improved thermophoretic probes that can sample particles with high spatial resolution. A bending vibration analysis for the instantaneous motion of a probe has been done together with direct observation of the probe motion and flow disturbance for systematic study of the effect of different designs on particle sampling. Direct observation of the motion of thermophoretic sampling probes revealed that the probe with a low stiffness would result in inaccurate particle sampling. Based on these, the thermophoretic sampling probe was modified to minimize probe vibration and flow disturbance and this modified design was confirmed to sample particles with higher spatial resolution than the original one by examining transmission electron microscope (TEM) images of particles collected in a flame.     

塔里木盆地塔河油区原油生物标志化合物在运移方面的应用探讨

塔河油区奥陶系原油的成熟度较高,且受生物严重降解.不同的生物标志化合物成熟度参数仅对有机质生成原油的不同阶段起到标尺作用,需优选既能较好地抗生物降解且适用于较宽的成熟度范围的指标来分析塔河油气运移的可能途径.三环萜烷/17α(H)-藿烷、重排甾烷/规则甾烷及Ts/(Ts+Tm)的比值是比较适用于塔河油区这种特殊性质的原油的生物标志化合物.根据研究,奥陶系原油油气存在两个注入通道,早期主要是由南向北方向运移,油气成熟度相对较低,成藏较早;晚期由东向西运移,原油成熟度相对于早期的较高,原油成藏稍晚.     

叠前深度偏移中的旅行时并行计算技术

旅行时计算技术是基于波动方程叠前深度偏移方法的核心内容，射线跟踪的数值计算精度和效率直接影响着介质成像质量和实用化。基于三维射线跟踪的微变网络方法和波前重建思路，提出一种适用于三维复杂介质地震波走时的快速算法。但它所需计算量巨大。采用并行计算技术，设计出基于“任务缓冲池”的动态负载平衡策略，在现有的分布式计算机上，实现了三维射线追踪和叠前深度偏移的并行计算。     

常速度梯度射线追踪与二维层速度反演

速度问题是勘探地震学的核心 ,可以借助常速度梯度射线追踪方法 ,从反演的角度探讨速度建模问题。在射线追踪方面 ,从程函方程出发 ,将复杂的速度场剖分成小的矩形单元 ,并假设在每个矩形单元内速度具有常速度梯度 ,由此导出的一组常速度梯度射线追踪公式 ,可实现非均匀介质的射线追踪 ,具有适应性强、精度高和快速的优点。在层速度反演方面 ,采用相干速度反演的思想 ,根据各向同性介质中 ,零偏移距射线在界面处是法向入射的原理 ,建立了合成共中心点道集与射线深度偏移的正反演关系 ,由此利用合成共中心点道集与观测的共中心点道集逼近 ,采用层剥离方法进行层速度反演。通过理论推导与模型试算得到如下的认识与结论 :常速度梯度射线追踪具有较高的计算精度与效率 ,公式采用向量形式很容易推广到三维 ;确定层速度采用的是正反演相结合的方法 ,可得到稳定的速度场 ;该方法屏弃了基于双曲时矩关系确定层速度场的假设 ,使其能适应任意的速度分布。     

Monotonic and cyclic oedometer tests on sand at high stress levels

In this paper, one-dimensional compression behavior of uniformly graded fine sand is studied with the use of oedometer test at elevated stress levels. To reach the elevated stress levels, testing is performed in a strain controlled manner. In addition, standard stress controlled testing method is also used at lower stress levels for the purpose of comparison. Specimens prepared with initial relative densities ranging from loose to dense are subjected to normal loading as well as hysteretic and repeated loading patterns. Results showed that there is a linear relationship between compressibility index and relative density. The magnitude of compression is mainly influenced by inundation where the compressibility behavior is found to be depending on the initial formation density. Regardless of the initial formation density, convergence to a similar compression index is observed with the hysteretically loaded samples whereas a continuous modification was obtained with repetitively loaded reformed specimens.     

Characterisation of inter-particle forces within agglomerated metallurgical powders

The strength of agglomerates of nickel flash furnace concentrate and dust was determined from experimental observations of agglomerates forming under controlled conditions, combined with mathematical equations from the literature. It was found that the agglomerates had a tensile strength ranging from 0.01 Pa to 38.7 Pa, while inter-particle forces ranged from 2.2 × 10^− 12 N to 1.5 × 10^− 10 N. These values were compared to the expected magnitude of van der Waals, electrostatic, magnetic and capillary forces within the agglomerates, and it was found that both electrostatic and van der Waals forces are likely to contribute to the cohesion of agglomerates, although sub-micron particles and the presence of sufficiently large asperities on the surface of particles limit the magnitude of van der Waals forces. Magnetic forces are large enough to contribute to the cohesion of dust agglomerates, which is in keeping with the high magnetite content of the recycle dust. It is postulated that electrostatic forces, acting over a longer range than van der Waals forces, may be responsible for initially bringing particles together. The methodology for determining inter-particle forces can be applied to the computer modelling of flash smelting systems, as well as other gas/particle systems such as fluidized beds.     

Investigation into Displacement of Placer Gold Particles

The experimental research in displacement of gold particles in washed-out thickness of sand-gravel layer is conducted. The parameters of ability of gold particles to migrate in pulp flow are determined, and their immersion into loose soil is investigated.     

三维合成炮叠前深度偏移

对国际上标准的SEG/EAEG模型进行了三维合成炮叠前偏移研究。与三维单炮叠前深度偏移不同 ,三维合成炮叠前偏移有一个叠前数据的合成过程 ,由于合成后数据量大大减少 ,所以合成炮偏移的计算量要比单炮偏移小得多。阐述了三维合成炮叠前偏移的实现过程 ,给出了相应公式。对SEG/EAEG盐丘模型的一个数据集进行了MPI并行计算 ,取得了良好的成像效果。所作的较多计算表明了三维合成炮叠前偏移的正确性和有效性 ,这为野外实际数据的三维叠前深度偏移提供了另一条有效途径。