among all the geophysical techniques, the magnetotelluric method has improved considerably in recent years and is widely being used in hydrocarbon exploration especially in regions where reflection seismic has difficulties. areas which are covered with high velocity rocks in the near surface are most popular cases. a huge high resolution magnetotelluric investigation was conducted in the sehqan...

This paper presents a new interpretation of the geometry of Triassic alignment of J. Sidi Mahdi –J. Zitoun in Medjerda Valley Plain (Northern Tunisia) based on detailed analysis of gravity and seismic reflection data. The main results of gravity analysis do not show a distinguish gravity anomaly over Triassic evaporites bodies. The positive gravity anomaly seems to be related to the entire stru...

most geologic changes have a seismic response but sometimes this is expressed only in certain spectral ranges hidden within the broadband data. spectral decomposition is one of the methods which can be utilized to help interpreting such cases. there are several time-frequency methods including: short-time fourier transform (stft), continuous wavelet transform (cwt), wigner-ville distribution (w...

Shallow high resolution 2-D and 3-D seismic reflection techniques are assisting in the subsurface delineation of a surface collapsc feature (sinkhole) at Weeks Island. Louisiana. Seismic reflection surveys were conducted in March 1994. Data from walkaway noise tests were used to assist selection of field recording parameters. The top of the salt dome is about 180 ft below ground surface at the ...

avo analysis is a technique which is widely used in industry and is applied on seismic prestack data. results from changes in seismic wave reflection amplitude versus offset can be used in extracting elastic properties and hence lithology and reservoirs pore fluid identification. before performing avo analysis studies, processing steps should be ensured that changes in reflection amplitude are ...

Geophysical imaging by using attenuation property of multichannel seismic reflection data was tested to map spatial variation of physical properties of rocks in a volcanic area. The study area is located around Miyakejima volcanic island, where an intensive earthquake swarm was observed associated with 2000 Miyakejima eruption. Seismic reflection survey was conducted five months after the swarm...

Substantial progress has occurred during the past 15 years in development of shallow CDP seismic-reflection techniques, but there are occasional interpretation problems with the resulting data. We discuss examples of the pitfalls of the method, along with some procedures to help avoid them. Problems that often occur include spatial aliasing of ground roll, interpreting processed ground-coupled ...

Seismic oceanographic studies from various oceans worldwide have indicated that the acoustic reflections are mostly observed along thermal boundaries within the water column. However, the authors present a case study of seismic data from Krishna-Godavari Basin which shows that salinity variations also play an important role in the occurrence of water column reflections. The observed reflection ...

We present an analysis of migration effects on seismic reflection images of very shallow targets. Reflection objectives in engineering, groundwater, and environmental investigations commonly occur at depths between 2 and 50 m. Because the observation surface is near these imaged reflectors, optical distortion may be so small that migration will not have any effect on the seismic image and may t...