|AVO and multispectra images of gas hydrates on the Hydrate Ridge off the Cascadia Margin|
Klaeschen, D.; Koenitz, D.; Bialas, J.; Kopf, A.; Flueh, E. R.; HYDGAS-Working (2001). AVO and multispectra images of gas hydrates on the Hydrate Ridge off the Cascadia Margin. Geophys. Res. Abstr. 3(774)
In: Geophysical Research Abstracts. Copernicus: Katlenburg-Lindau. ISSN 1029-7006; e-ISSN 1607-7962
|Auteurs|| || Top |
- Klaeschen, D.
- Koenitz, D.
- Bialas, J.
- Kopf, A.
- Flueh, E. R.
During cruise Sonne SO-150, improved geophysical methods were used to identify and quantify the spatial variation of gas hydrates across Hydrate Ridge. Narrowly spaced receivers on the seafloor (approximately 200 m apart), shallow and deep towed systems, and a broad range of source frequencies (5 Hz to 2 kHz) were used to guarantee pristine data quality. Here, special attention will be given to parameters which will assist in gas hydrate identification and quantification. The new geophysical data will be compared and calibrated using the results from direct measurements on recovered core as well as along the borehole wall (downhole logging) at ODP Site 892. Calibration of the geophysical information will allow us to optimize data processing and interpretation. The results from cruise Sonne SO-150 will significantly broaden the understanding of seismic signals in hydratebearing sediments, and thus will add a quantitative component to the overall gas hydrate research.Five receiver assemblages in three locations at Site 892 (ODP Leg 146) and at two future ODP drillsites (ODP eg 204, scheduled for autumn 2002), provided a wealth of data from 5 different sources used. During intervals of data retrieval and OBH/OBS refitting, a total of 1490 km of seismic reflection profiles were acquired using five different source (broad frequency range) and three different streamer (surface and deep tow) configurations. The narrowly spaced grid of seismic reflection and Parasound lines permits us to tie in the results from the receiver experiments for quantitative estimates. First results of the multispectra images of gas hydrates on the Hydrate Ridge will be presented.