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Denis Beloborodov. Matthew A Perras. John Koestel. Beatriz Quintal.

Denis Anikiev. Vladimir Kazei. Martin Ostoja-Starzewski. Vadim Lisitsa. Research Items Conference Paper. In the earth sciences, poroelasticity is essential in many applications, for example, in hydrogeology, in seismic monitoring of CO 2 reservoirs, etc. We present a new treatment of this problem based on the so-called pseudo-transient method.

The idea is that at each time step, another pseudo iteration causes the slow mode to attenuate quickly. As a result, very fine time-stepping is unnecessary and the time-stepping is controlled by a standard Courant stability condition for the fast P-wave. Stiffness tensor dispersion and seismic attenuation in fractured rocks modeled using the T-matrix approach and Krauklis Wave theory.

Litecoin calculators T-matrix approach can be used to calculate the effective properties of rocks. In this study, we demonstrate that the T- matrix method generalized optical potential approximation is capable of calculating the effective viscoelastic properties of fractured rocks, while taking into account the spatial distri- bution of fractures, as well as, the effect of low-velocity and dispersive Krauklis waves, arising in thin fractures.

We show that the developed theory can be used with any homogenisa- tion scheme for rock physics applications. In this study, we introduce viscoelastic components which have complex mod- uli of the Krauklis wave — "Krauklis substance". As a result, the effective properties of a fractured rock become complex.

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We analyse the stiffness tensor dispersion and seismic attenua- tion, as well as, anisotropic behavior of seismic waves, caused by thin fractures filled with visloelastic substance. We demon- strate the results for two models of fractured carbonate rock, having a set of fluid filled aligned fractures.

One of the assumptions of the Marchenko method is that the medium is lossless. One way to circumvent this assumption is to find a compensation parameter for the lossy reflection series so that the lossless Marchenko scheme can be applied. The main goals of this work are to: This method is based on the minimization of the artefacts produced by the lossless Marchenko scheme.

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Artefacts have a very specific behavior: Thus, they can be recognized. This approach is supported by a synthetic example for a 1D acoustic medium without a free surface. Full-text available. Aug Thesis Alkhimenkov Supervisors: Joeri Brackenhoff, Prof.

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The T-matrix approach for the mathematical modeling of the effective elastic properties of hydrocarbon reservoirs. May Various methods of the effective medium theory EMT —the T-matrix approach optical potential approximation and coherent potential approximationMori—Tanaka method, generalized singular approximation, etc. The relationship of the different approaches perturbation btc hasher, self-consistent methods, and variational principles is demonstrated.

The classification of the methods by the degree of complexity of solving the inverse problem is suggested. An example of the theoretical modeling of an oil- gas- and water-saturated rock with the oriented axis of the fractures is presented. The relationship of the different approaches perturbation theory, self-consistent methods, and variational principles is demonstrated. The classification of the methods by the degree of complexity of solving the inverse problem is suggested.

An example of the theoretical modeling of an oil- gas- and water-saturated rock with the oriented axis of the fractures is presented. Conclusions about the applicability of different methods for rock modeling are made. In this study we review and compare different methods of the EMT bitcoin free на русском present the guidelines for determining the effective properties of the medium in rock physics modeling.

Влияние пространственного взаимодействия включений на эффективный тензор упругости порово- трещиноватых сред. Jan Задача определения эффективного тензора упругости микронеод- нородной и, в общем случае, макроскопичеки однородной и анизотроп- ной композитной среды относится к проблеме взаимодействия многих тел. Решение такой задачи возможно лишь приближенно. В работе рас- сматривается решение такой задачи для порово-трещиноватой среды — терригенной горной породы, упругие свойства которой анизотроп- ные.

Причем, анизотропия упругих свойств вызвана различными фак- торами — как собственной анизотропией глинистых минералов, так и преимущественной ориентацией неизометричных неоднородностей по- роды. Различные методы теории эффективных сред ТЭС для вы- числения эффективного тензора упругости порово-трещиноватых сред используют так называемые гипотезы эффективного поля. Так, на- пример, метод Т-Матрицы, метод Мори-Танака, метод Обобщенного Сингулярного приближения и метод Эффективного Поля используют гипотезы эффективного поля в различных вариациях.

Таким образом, различные методы ТЭС показывают близкие результаты. В случае гор- ной породы, которая рассматривается как природный композит, боль- шое значение имеет аппроксимация реальной среды некой парамет- рической модельной средой, отражающей основные особенности мик- роструктуры породы, которая, в свою очередь, является следствием особенностей формирования конкретной породы.

Следовательно, вы- бранная модель среды и выделенные модельные параметры играют очень важную роль в моделировании.

Для подтверждения этого те- зиса было проведено моделирование эффективных упругих характе- ристик порово-трещиноватой породы двумя различными методами: Т- матрицы и Обобщенного Сингулярного приближения для двух разных параметрических моделей одной и той же горной породы, построенных независимо на основе визуального анализа микроструктуры породы в масштабе шлифа.

Каждая из построенных моделей имеет разное коли- чество параметров, которые также различны. Однако общим является то, что при моделировании таких пород необходимо учитывать жест- кость контакта минеральных зерен и органического вещества, а также степень связности компонент.

Найдены параметры каждой модели и определена область изменения пористости породы, в которой обе модели имеют сходные упругие свойства. Hydrocarbon reservoirs generally are composed of rocks with pores and cracks that are filled with different fluids: The fluids filling the pores have a significant impact on the effective characteristics of the reservoir.

Methods of Effective Medium Theory EMT can simulate the effective elastic properties of porous-fractured media, such as rocks. The practical applications of EMT methods for fractured porous rocks are important for fracking, reservoir property prediction using seismic data and understanding the AVO properties of reservoirs.

To date, a huge number of different EMT approaches exist and it is very difficult to choose the best one. Each of the most popular EMT methods for the modeling of effective elastic properties of reservoir rocks, of course, generate different results. The main goal of the paper is to find the most optimal method of effective medium theory.

It can be shown that the T-matrix approach is the most general, modern and adequate for the rock physics applications. A practical application dogechain blockchain the T-matrix approach was developed for the inverse problem with a special choice of comparison body. Also, other theories exist for simulation the effective proprieties of rocks: The EMT has a close connection with these theories.

A connection between the Effective Medium Theory and Poroelasticity are shown. Our conclusions are verified on experimental data. As an example of practical utilization of the T-matrix approach mathematical models for the effective elastic properties of carbonate reservoir rocks including oolitic limestone are constructed. Apr Recently unconventional reservoirs attract more and more attention in prospecting geophysics.

Unconventional reservoirs often exhibit anisotropic physical properties due to specific features of their microstructure and texture. In the work a theoretical modeling of effective elastic properties of such a reservoir - fractured carbonate rock of low porosity - is considered.

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