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| Title: | Seismic characterization of hydrates in faulted, fine-grained sediments of Krishna-Godavari basin: Unified imaging |
| Authors: | Jaiswal, P. Dewangan, P. Ramprasad, T. Zelt, C.A. |
| Citation: | Journal of Geophysical Research, vol.117; 2012; 13 pp, B04306; doi:10.1029/2011JB009024 |
| Issue Date: | 2012 |
| Publisher: | American Geophysical Union |
| Abstract: | A combination of diffusion and advection in fine grained sediments can create a patchy Bottom Simulating Reflector (BSR) which has little to no apparent correlation with the overlying hydrate distribution. Using 2D seismic data from faulted, clay-rich sediments in the Krishna-Godavari (KG) basin, we show both the hydrate distribution and the BSR structure are fault controlled. Our demonstration hinges upon a kinematically accurate P wave velocity (V sub(P)) model which is estimated using a composite traveltime-inversion, depth-migration method in an iterative manner. The flexibility of the method allows simultaneous usage of traveltimes from multiple, discontinuous reflectors. The application begins with a simple V sub(P) model from time processing which is reflective of a diffusive, continuous, hydrate– and free gas–bearing system. The application converges in three iterations yielding a final V sub(P) model which is suggestive of a patchy distribution of hydrates and free gas possibly developing through a combined diffusive-advective system. The depth image corresponding to the final V sub(P) model can be interpreted for faults that suggest ongoing tectonism. The BSR appears to be truncated at active faults zones. Both the final V sub(P) model and the corresponding depth image can be reconciled with the hydrate distribution and BSR depth at logging/coring sites located approx. 250 m away from the line by projecting the sites along the strike direction of the regional faults. |
| Document type: | Journal Article |
| Copyright: | An edited version of this paper was published by AGU. Copyright [2012] AGU. To view the published open abstract, go to http://dx.doi.org/10.1029/2011JB009024 |
| URI: | http://drs.nio.org/drs/handle/2264/4067 |
| Appears in Collections: | Geology & Geophysical Sciences
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