RESEARCH INTERESTS:
I find the petrologic and
tectonic evolution of active oceanic plate margins, mostly convergent margin
systems of the Western Pacific, particularly fascinating. I've worked on
the tectonics and metamorphism of supra-subduction zone regions and the associated
production of serpentine mud volcanoes in convergent margin settings.
These phenomena bear on problems related to geochemical mass balance in the
plate tectonic cycle. I'm also working on aspects of rifting in suprasubduction
zone regions. This has maintained my interest in mid-ocean ridge crest
structural and petrologic processes and, of course, seafloor volcanism.
My recent participation on IODP Expedition 305 provided an opportunity to
make comparisons of the nature of metamorphic processes in the mid-ocean
ridge environment with that at convergent margins. Serpentinization
occurs in both, but differences between the process in the two environments
will tell us a great deal about geochemical cycles associated with plate
tectonics. In addition to working with seafloor samples, one of the techniques
I've used to engage in this sort of research is remote sensing, mainly side-scan sonar imagery and bathymetric
studies of seafloor textures and morphology. I like to be able
to do field work in the deep oceans, hence my interest in deep submergence
science and deep ocean drilling. For the future, I see a burgeoning
growth in the effort to instrument the ocean floor and the development of
seafloor observatories. As a consequence, I am interested in the design
of precision coring devices and of mini-CORKing devices for gravity and piston
core holes to augment ODP drilling sites that house down-hole observatories.
FIELD EXPERIENCE:
38 marine geophysical/geological research cruises:
9 months as shipboard scientist aboard R/V KANA KEOKI (9 cruises, 1971-1980)
1 month total as shipboard scientist aboard R/V TERI TU and R/V NOI'I
(2 cruises, 1972 &1974)
3 months as co-chief scientist aboard R/V KANA KEOKI (4 cruises, 1981
-1985)
2 months as shipboard scientist aboard D/V GLOMAR CHALLENGER (1 cruise,
1978)
4 days aboard chartered yacht (side-scan sonar and bottom photography surveys
of Rabaul Caldera, PNG, 1985)
1 day dredge sampling Rabaul caldera aboard R/V MOANA WAVE (1985)
1 month total as chief scientist aboard R/V ATLANTIS II directing ALVIN
submersible operations (2 cruises, 1987)
1 month total as co-chief scientist aboard R/V ATLANTIS II assisting in
directing ALVIN submersible operations (2 cruises, 1987)
1 week as chief scientist aboard R/V FRED H. MOORE (1 cruise, 1987)
2 weeks as shipboard scientist aboard R/V HAKUHO MARU (1 cruise,
1987)
2 months as co-chief scientist on JOIDES Resolution, ODP Leg
125 (1989)
3 weeks as shipboard scientist aboard R/V Thomas Washington, (Dec.
1991)
2 weeks as co-chief scientist on Yokosuka/Shinkai 6500. Invited to participate
on Japan-US cooperative diving efforts in the Mariana forearc (Nov. 1992)
2 weeks as co-chief scientist on Yokosuka/Shinkai 6500. Invited to participate
on Japan-US cooperative diving efforts in the Mariana forearc as co-chief
scientist (Sept. - Oct. 1993)
2 weeks as co-chief scientist on Yokosuka/Shinkai 6500. Invited to participate
on Japan-US cooperative diving efforts in the Mariana forearc as co-chief
scientist (Sept. 1995)
4.5 weeks as chief scientist of R/V Thomas G Thompson ROV (Jason, WHOI)
and coring cruise in the Mariana forearc (Jan.- Mar, 1997).
2.5 weeks aboard the R/V Moana Wave as chief scientist (Aug. - Sept., 1997)
4 day equipment testing aboard the R/V Melville (chief scientist Nov 30-Dec.
3, 1999)
3.5 weeks scheduled aboard the R/V Melville (chief scientist Feb. 10 -
Mar. 1, 2001)
3 weeks aboard the Joides Resolution Mar. 2001
6 weeks aboard R/V Ewing
55-day cruise on the R/V Thompson as Chief Scientist to do DSL-120 and Jason2
work on Mariana forearc
seamounts (2003)
IODP Expedition 305, 2 months as Scientific Shipboard Participant (Lead Metamorphic
Petrologist) Jan. 8 to Mar. 2, 2005.
3 weeks as co-chief scientist on Yokosuka/Shinkai 6500 to participate in
diving efforts in the Mariana backarc basin (July. - Aug. 2005)
field work on Papuan ophiolite sequence, PNG (1977)
field work on active volcanoes of the Mariana island arc (1978-1987)
field work on ash distribution of 1937 Vulcan eruption, Rabaul, PNG (1985)
field work in serpentinite terrains of central California (1985-1988,
2005)
field work on Guam tectonics (1981-1997)
Duties on geophysical research cruises have included directing acquisition
of data from the Hawaii Institute of Geophysics side-scan sonar and bathymetry
mapping systems SeaMARC II and HMR-1 and from multi-beam bathymetry systems
(SeaBeam, Hydrosweep, Japanese systems, EM300), directing rock dredging operation,
onboard petrographic analysis of rocks, planning and directing ALVIN submersible
research (14 dives) and , planning and directing Jason/Medea ROV submersible
research (5 lowerings), planning and directing ODP Leg 125 and assisting
in planing and directong Site 1200 operations on ODP Leg 195, directing and
assisting in piston and free-fall sediment coring, analysis for biological
assemblages and sedimentary characteristics of cores, assisting in heat flow
probe deployment and analysis of heat flow recordings, assisting in
deployment of ocean bottom seismometers and sonobuoy recorders, directing
and assisting marine seismic experiments using explosive charges and airguns,
interpretation of seismic records, monitoring navigational equipment, including
satellite navigation systems, LORAN-C, GPS, and mini-rangers, monitoring
bathymetric profiling equipment and multi-beam bathymetry systems (SeaMARC
II, SeaBeam, Hydrosweep, Japanese multinarrow-beam, and EM300 systems), geologic
interpretation of seismic reflection profiles, digitizing bathymetric reflection
profiles and bathymetry contour maps, production of bathymetric charts both
by hand from reflection profile data and using a variety of modern software
packages, tectonic interpretation of bathymetry and side-scan data initial
processing of MCS data collected aboard the R/V Ewing.
Shore-based work has included chemical analysis of rock samples (primarily
basalt and peridotite samples) for major and trace elements using the following
techniques: Atomic Absorption Spectrophotometry (Hawaii Institute of
Geophysics), X-Ray Diffraction (Hawaii Institute of Geophysics), X-Ray Fluorescence
(Hawaii Institute of Geophysics and Scripps Institution of Oceanography),
Scanning Electron Microscopy, (Virginia Institute of Marine Sciences - for
undergraduate senior thesis; Hawaii Institute of Geophysics), Electron
Microprobe (Hawaii Institute of Geophysics; Princeton University), Induction
Coupled Plasma Spectrophotometry (Lamont-Doherty Geological Observatory),
and Rare Earth analysis by Isotope Dilution Mass-spectrometry (Hawaii Institute
of Geophysics) and Induction Coupled Plasma Spectrophotometry (Lamont-Doherty
Geological Observatory), Raman spectyroscopy with S. Sharma at University
of Hawaii.