Monterey Bay Aquarium Research Institute

Paull Fluid Flow Cruise
October 2 - October 8, 2000
Monterey Bay
Logbook

October 2, 2000: Day #1


A seep at the top of Extravert Cliff

Charlie Paull writes: Twelve thermal gradient measurements were taken on a transect running across the trend of the Monterey Bay fault zone over Extravert Cliff, at a depth range of 972 m - 992 m. Eight of the measurements were in background sediments and showed modest temperature gradients-not suggesting flow.

On top of Extravert Cliff, three measurements were taken on the flank of a small circular seep community, 1.5 m across and 20 cm high. The structure had abundant living clams on the lower flank and a barren zone in the center. Temperature gradients on the top were markedly different from all the others-1/2 degree centigrade warmer and isothermal. deployed four peepers across the mound.

Two thermal gradient measurements were also made in another elliptical community. Thermal measurements from the central barren zone showed temperatures that were over 2 degrees centigrade higher than the background cores. Four peepers and a temperature monitoring probe were deployed at this site.


Next Day