Publication Date:
2019-07-17
Description:
During RV SONNE cruise SO173-1, carried in the framework of the Cooperative Research Center (SFB) 574 (Volatiles and Fluids in Subduction Zones) in July and August 2003, an area offshore Nicaragua has been surveyed with the IFM-GEOMAR deep-towed multichannel seismic system (DTMCS). In total 13 NW-SE striking profiles running parallel to the continental slope were recorded in the water depths between 1000 and 2500 m covering an area of approximately 700 square km. This study presents some new results from the ongoing investigations with these seismic profiles. The continental margin off Nicaragua is dominated by deeply incised canyons and numerous mound structures, as well as slides at the lower slope. Most of these mud mounds built positive topographic expressions (up to ca. 130 m) on the seafloor. They are characterized by transparent or semi-transparent seismic facies in the cylinder-like feeder channel tapering upward to cone shape geometry. The mud mounds are of different size and different stages of development. The distribution of the mounds show two distinct orientations (NW-SE and NE-SW) and are most probably controlled by faults. The widespread occurrence of gas hydrate is imaged by a BSR visible in most parts of the survey area. For the first time, our data show that the BSR is continued but uplifted beneath some mud mounds.
Repository Name:
EPIC Alfred Wegener Institut
Type:
Conference
,
notRev
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