December 23, 2024

The R/V Pelican Sets Sail, and Data Collection Begins

The R/V Pelican Sets Sail, and Data Collection Starts

by
Cecilia McHugh|January 16, 2022

Scientists are mapping the seafloor and subseafloor in between Haiti and Jamaica, to assess the capacity for earthquakes.

The coring system were using is the “Big Bertha” with a coring head weight of 3500 pounds. It can recuperate up to six meters of sediment from the seafloor. Photo: Cecilia McHugh

The coring system were using is the “Big Bertha” with a coring head weight of 3500 pounds. It can recuperate approximately six meters of sediment from the seafloor. Picture: Cecilia McHugh

The R/V Pelican. Photo: Cecilia McHugh
The R/V Pelican left Ocho Rios on January 8, reaching our first location along the Jamaica Passage on January 9.
Throughout the daytime, we run the CHIRP subbottom profiler, which lets us see an acoustic picture of the seafloor and about 10 meters into the subsurface, plus the multichannel seismic study, which permeates much deeper into the subsurface (~ 100 m) in this setting. We gather sediment cores and heat circulation measurements at night.
Due to rough seas with winds of 15 knots, swells as high as eight feet, and small technical concerns, the multichannel seismic survey and sub-bottom profiling were sluggish to begin. The coring was really successful and we recuperated three gravity cores in water depths varying from 2500 to 2700 meters.
A gravity core is a metal pipeline with a really heavy weight (core head) that makes the core descend to the seafloor by the force of gravity. It penetrates the sediments beneath the seafloor and recovers layers of sediment, like a layered cake, that expose the history of a location, with the earliest layer at the bottom and the youngest layer on top.
Together, these measurements and the ones we collect over the coming weeks will assist us examine the possible earthquake hazard along the Enriquillo-Plantain Garden fault, situated between Haiti and Jamaica.
Since January 13, all systems are fully operational and we are gathering fantastic information.