Wave Propagation Modeling and Amplitude-Variation-with-Offset Response in a Fractured Coalbed

• Autorzy: Lin Q-X. , Peng S-P. , Du W-F. , Shi S-Z. , Gou J-W.

Identyfikatory

DOI

10.1515/acgeo-2015-0014

• Języki publikacji: EN

Abstrakty

EN

Coalbed methane can be detected employing the amplitudevariation- with-offset technique. However, there are two issues in applying this technique to a coalbed: strong azimuthal anisotropy resulting from high-density fractures, and the seismic response being composed of many or several individual reflections within the coalbed. To overcome these difficulties, we present an exact solution for reflections in extensive dilatancy anisotropy media. First, we build a three-layer model and simulate the wave propagation in this model. Then we derive an exact P- and converted S-wave reflection coefficient equation based on boundary conditions. Finally, substituting given model parameters into the exact equation, we obtain the variation in the reflection coefficient with incidence angle. The results show that the fracture factors, wavelet frequency and thickness of the coalbed have different effects on the reflection coefficient. Furthermore, we create a synthetic seismogram by forward calculation, and the result fits well with results of the exact equation.

Słowa kluczowe

EN

extensive-dilatancy anisotropy; amplitude-variation-with-offset response; wave propagation for wave field modeling; reflection coefficient

PL

anizotropia; propagacja fali; modelowania pola falowego; współczynnik odbicia

• Wydawca: Instytut Geofizyki PAN ; Springer
• Czasopismo: Acta Geophysica
• Rocznik: 2015
• Tom: Vol. 63, no. 3
• Strony: 815--842
• Opis fizyczny: Bibliogr. 32 poz., rys., tab., wykr.

Twórcy

autor

Lin Q-X.

• State Key Laboratory of Coal Resources and Mine Safety, China University of Mining & Technology (Beijing), Beijing, China

autor

Peng S-P.

• State Key Laboratory of Coal Resources and Mine Safety, China University of Mining & Technology (Beijing), Beijing, China

autor

Du W-F.

• State Key Laboratory of Coal Resources and Mine Safety, China University of Mining & Technology (Beijing), Beijing, China

autor

Shi S-Z.

• State Key Laboratory of Coal Resources and Mine Safety, China University of Mining & Technology (Beijing), Beijing, China

autor

Gou J-W.

• Geophysical Prospecting Institute, China National Administration of Coal Geology, Zhuozhou, China

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