Shatsky Rise

The airgun chute on the stern of the R/V Marcus Langseth.

In July-September 2010, I sailed as a research scientist on a marine multichannel seismic reflection (MCS) and ocean bottom seismic (OBS) refraction survey of Shatsky Rise aboard the R/V Marcus Langseth (MGL1004). Shatsky Rise is a 124-145 Million year old large oceanic plateau located 1,600 km southeast of Japan.  The objective of the study is to determine the internal structure and composition of the plateau and to decipher its magmatic emplacement and tectonic history, which is important for understanding mantle dynamics and terrestrial magmatism.

Map of the R/V Marcus Langseth MGL1004 seismic refraction and reflection survey. Green and blue circles: OBS locations. Yellow line: refraction shot path. Red line: MCS profiles. Purple line: Additional high resolution bathymetry survey path. Red dots: Future proposed MCS profile locations.

We deployed and recovered 28 OBSs, shot two refraction profiles, and acquired ~1,800 km of MCS data across TAMU Massif, which is the largest and oldest edifice on Shatsky Rise.  My interests are in imaging the internal structure of TAMU Massif in three dimensions using seismic traveltime tomography and analyzing the shallow oceanic crustal structure and its variability from near-normal oceanic crust to the crest of TAMU Massif using 6-km offset multichannel seismic reflection data. The results from this work, combined with those of my colleagues, will help to distinguish between various possible mechanisms of magmatic emplacement of this large oceanic plateau.