An important problem that confronts marine geochemists today is balancing the fluxes of
elements in the oceans. Thirty-two years ago Mackenzie and Garrels (1966) could not
produce such a balance without invoking "reverse weathering." At the time this
paper was published, seawater circulation through the oceanic crust was only a hypothesis.
Much of my research has focused on a myriad of problems associated with fluid
circulation through the oceanic crustcirculation caused by the intrusion of basaltic
magma; differential lithospheric cooling on mid-ocean ridge flanks; compression along
zones of subduction, and differences in head gradient on continental shelves and margins.
Although these geologic settings and mechanisms for fluid flow are vastly different, in
each of them, the fluid in basement reacts with and changes the crust as it is
transported, thus resulting in chemical, mass, and thermal fluxes to and from the oceans.
By examining this range of settings, one can study the continued alteration and evolution
of the crust as it passes along a continuum from the ridge axis to the flanks before it is
I will highlight some of my work that relates to global geochemical fluxes in each of
the oceanic settings mentioned above, and I will provide a direction for determining these
fluxes. The methods and results from this work also are applicable for studies of
microbial and benthic communities, the nature and size of geologic deposits, and crustal
behavior in pelagic animal colonies- Siphonophores, salps, and Pyrosoma
Last updated: December 19, 2000