masjed soleyman dam site is located in the zagros mountain of western iran, which is one of the most seismically active zones of the alpe-himalayan belt. after impounding of dam, the seismicity of area increased considerably, showing the impact of reservoir (177 m height, 261 million m3) in changing the rate of seismicity in the area. we have analyzed the seismicity of area in terms of the spat...

The frequency–magnitude distribution was spatially mapped beneath Makushin Volcano, Unalaska Island, Alaska using an earthquake catalog of 491 events that occurred between July 2001 and April 2005. An area of high seismic b-values (∼2.0) is found ∼4 km east of Makushin's main vent at a depth between 4 and 7 km. The anomaly is statistically significant based on Utsu's p-test [T. Utsu, On seismic...

b a c k g r o u n d & aim: in many studies, the survival of patients with chronic kidney disease who are treated with peritoneal dialysis technique has been considered, while this is possible in peritoneal dialysis  patients  to switch  to another  treatment.  to achieve  more  accurate  estimation  of patient survival is necessary to examine all events. the purpose of this study is to estimate...

This paper presents least-squares wave equation AVP (Amplitude versus Ray Parameter) migration with non-quadratic regularization. We pose migration as an inverse problem and propose a cost function that makes use of a priori information about the AVP common image gather. In particular, we introduce two regularization goals: smoothness along the ray parameter direction and sparseness in the dept...

pore pressureis defined as the pressure of the fluid inside the pore space of the formation, which is also known as the formation pressure. when the pore pressure is higher than hydrostatic pressure, it is referred to as overpressure. knowledge of this pressure is essential for cost-effective drilling, safe well planning, and efficient reservoir modeling. the main objective of this study is to ...

Seismic images and the geologic information they provide contribute significantly to our understanding of the earth’s subsurface. In this thesis, I focus on methods relevant for constructing and interpreting seismic images, including methods for velocity estimation, seismic imaging, and interpretation, which together address key aspects of reflection seismic data processing. Specifically, I pro...

Channels have always been important geologic features in the exploration for oil and gas. With 3-D seismic data they can often be mapped easily on time or depth slices. In other situations they can be difficult to detect, due to structural complexity or other factors. There are a number of image-processing algorithms that can be used to enhance linear features such as channels in 3-D seismic vo...

Velocity dispersion and attenuation in rocks are coupled properties that depend on the pore fluids and fluid flow. Attenuation shows a peak at high partial gas saturation. The amplitude of this peak increases with frequency. With full saturation, velocities rise but dispersion remains approximately constant. A substantial frequency shift occurs with decreasing permeability or fluid mobility. Th...

In this paper, it was firstly confirmed by FEM analysis of ground during earthquake that two kinds of techniques using both displacements of hollow and natural grounds in seismic deformation method were equivalent. Then, the authors were proposed a criterion for evaluating applicability of seismic deformation method, based on comparison of calculated results of both the above-mentioned techniqu...