Seismic processing

V.G. Gomes de Oliveira, MinenaMet (Mexico) No.35, 93-132(1965) (Span) CA 66, 2947(1967) (Some general notions on explosives and the role they fulfil in the seismic process)... 

M.A. Sadovskii and V.F. Pisarenko, Seismic Process in Block Medium, Nauka Publishers, Moscow, Russia, 1991, [in Russian]. 

Among these cracks, the widest cracks with 1 m opening occurred in Shuanghe Village. The cracks changed with seismic process. Firstly, the ground surface was ruptured under tensile force with wide opening and certain vertical displacements. After the... 

Sadovsky, M.F., Bolkhvitinov, L.G., Pisarenko, VF. 1987. Deformatum of geophysical media and seismic process. Nauka, Moscow. 

In this entry only two problems have been presented representation of the power spectral density (PSD) and correlation by means of complex fractional moments and filter equations. Regarding the first problem, it has been shown that both PSD and correlation may be represented by the so-called fractional spectral moments (FSMs). The latter are the extension of the classical spectral moments introduced by Vanmarcke (1972) to complex order. The appealing in using these FSM is that they are able to reconstruct both PSD and correlation. As a result, it may be stated that FSM functiOTi is another equivalent representation of PSD and correlation. Moreover it has been shown that with a limited number of informations (few FSM), the whole PSD and correlation may be restored, including the trend at infinity. Extension to multivariate seismic process has been also provided in both frequency... 

Implementation of elastic anisotropy is of increasing importance for seismic processing and interpretation. Armstrong et al. (1994) discuss fundamental characteristics and consequences of elastic anisotropy for seismic and acoustic methods. Wang (2002) gives a detailed discussion of elastic anisotropy of sedimentary rocks. Lo et al. (1986) analysed laboratory measurements at the Berea sandstone, Chicopee shale, and Chelmsford granite. 

Sonic logs. The sonic log provides in situ measurement of the speed of sound in the formation over the scale of the sonde. It can only be used in open, uncased holes. The measurement is useful in seismic processing, it can be used to infer porosity but not that accurately and can be used to identify the rock type since the sound speed is a definite characteristic of each type of rock. Further detail can be found in [45, 138]. 

After often a lengthy period (several months) of acquisition and processing, the data may be loaded onto a seismic workstation for interpretation. These workstations are UNIX based, dual screen systems (sections on one side, maps on the other, typically) where all the trace data is stored on fast access disk, and where the picked horizons and faults can be digitised from the screen Into a database. Of vital Importance is access to all existing well data in the area for establishing the well - seismic tie. 2D data will be interpreted line by intersecting line, and 3D as a volume. 

Keywords reducing uncertainty, cost-effective information, ranking sources of uncertainty, re-processing seismic, interference tests, aquifer behaviour, % uncertainty, decision tree analysis, value of information, fiscal regime, suspended wells, phased development. 

Consumption of natural gas, as of the mid-1990s, was about 2000 x 10 /yr. Using seismic detection equipment, exploration firms search for gas reserves buried deep underground and beneath the sea floor. Advanced computer systems process the seismic data to pinpoint the most likely locations for reserves. These advanced systems have both cut the time required for data analysis, by 80%, and gready improved the success rate for new drill rigs. 

The commercial value of a clay deposit depends on market trends, competitive materials, transportation faciflties, new machinery and processes, and labor and fuel costs. Naturally exposed outcrops, geological area and stmcture maps, aerial photographs, hand and power auger drills, core drills, earth resistivity, and shallow seismic methods are used ia exploration for clays (32). Clays are mined primarily by open-pit operation, including hydraulic extraction however, underground mining is also practiced. 

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