EqPac benthic leg completed



In December 1992, the U.S. JGOFS Equatorial Pacific Process Study (EqPac) completed a 43-day cruise on which benthic processes affecting carbon fluxes were studied. One of the major goals of EqPac is to understand the role of deep water and benthic processes on the cycling and ultimate removal of carbon and related elements from the oceans.

Like the other U.S. JGOFS EqPac studies, the benthic expedition followed a track along 140°W from 12°S to 9°N. Data from deep hydrocasts, in-situ measurements of benthic fluxes, and several coring techniques were used to test four hypotheses: that benthic fluxes and burial rates are a function of particle rain rate, bottom-water chemistry, and bioturbation; that regions of high burial and benthic flux coincide with areas of surface upwelling and enhanced primary production; that destruction of particulate organic matter below a depth of 1 km in the ocean is dominated by the decomposition that takes place in surface sediments; and that accumulation of biogenic phases in surface sediments is proportional to the present-day export production modified by benthic fluxes.