seismic waves are non-stationary due to its propagation through the earth. time-frequency transformsare suitable tools for analyzing non-stationary seismic signals. spectral decomposition can reveal thenon-stationary characteristics which cannot be easily observed in the time or frequency representationalone. various types of spectral decomposition methods have been introduced by some researche...

Due to low stiffness of braces after yielding, the structures with buckling-restrained braces (BRBs) experience high residual drifts during an earthquake, which can be intensified by aftershocks and causes considerable damages to structures. Also, due to poor distribution of stiffness, this problem is exacerbated for irregular structures. Recently, the yielding brace system (YBS) has been intro...

Blast-induced seismic wave is very important to theory study of structure damage and stability analysis of corresponding geotechnical engineering; however it is not well solved. Based on measured data of Lafarge quarry, shortcoming of traditional analysis method is pointed out. Wavelet analysis method is presented to describe spectral characteristics and energy distribution of blast-induced sei...

My choice of research projects over the past decade has been rather eclectic, covering aspects relating to both seismic sources and Earth structure. There is, however, a consistent theme, and that is a fascination with the large variety of methods for extracting pertinent information from seismic data. In this thesis, I give an brief, largely chronological outline of the steps and insights that...

Seismic data comprise many traces that provide a spatiotemporal sampling of the reflected wavefield. However, such informationmay suffer from ambient and random noise during acquisition, which could possibly limit the use of seismic data in reservoir locating. Traditionally, fixed transforms are used to separate the noise from the data by exploiting their different characteristics in a transfor...

Today, the major challenge in reservoir characterization is integrating data coming from different sources in varying scales, in order to obtain an accurate and high-resolution reservoir model. The role of seismic data in this integration is often limited to providing a structural model for the reservoir. Its relatively low resolution usually limits its further use. However, its areal coverage ...

Obtaining seismic images with good quality in hardrock environments has been challenging. This condition applies to many mineral explorations using seismic methods including our study area where the data quality is strongly affected by soft, near-surface materials and a reflector with low contrast in rock physical properties. Until recently, no effective processing has been applied to the seism...

a new and significant source of information on earthquake studies has been provided by space geodesy. the data which are gathered by various techniques of space geodesy, can quantify potential of seismic activity in the region of interest. to achieve this goal, the main advantage of extra-terrestrial geodetic data in comparison with the conventional data from geology and seismology is the abili...

Information about reservoir properties usually comes from two sources: seismic data and well logs. The former provide an indirect, low resolution image of rock velocity and density. The latter provide direct, high resolution (but laterally sparse) sampling of these and other rock parameters. An important problem in reservoir characterization is how best to combine these data sets, allowing the ...