A5013765148- Geological and Geochemical Analysis
- Geology and Paleoclimatology Research
- Hydrocarbon exploration and reservoir analysis
- Methane Hydrates and Related Phenomena
- Geological and Geophysical Studies
- earthquake and tectonic studies
- Geological formations and processes
- Paleontology and Stratigraphy of Fossils
- Geochemistry and Geologic Mapping
- Geological Studies and Exploration
- Geological and Tectonic Studies in Latin America
- Marine Biology and Ecology Research
- Microbial Community Ecology and Physiology
- Underwater Acoustics Research
- Oceanographic and Atmospheric Processes
- Geochemistry and Elemental Analysis
- Geomagnetism and Paleomagnetism Studies
- Underwater Vehicles and Communication Systems
- High-pressure geophysics and materials
- Enhanced Oil Recovery Techniques
- Building materials and conservation
- Seismic Imaging and Inversion Techniques
- Marine and coastal ecosystems
- Drilling and Well Engineering
- Seismic Waves and Analysis
Woods Hole Oceanographic Institution
2013-2024
Institut Français de la Mer
2022
U.S. National Science Foundation
2019
Rutgers, The State University of New Jersey
2004
University of Washington
1985-1986
Seattle University
1985
Author Posting. © Oceanography Society, 2007. This article is posted here by permission of Society for personal use, not redistribution. The definitive version was published in 20, 1 (2007): 50-65.
The TAG active hydrothermal mound, located 2.4 km east of the neovolcanic zone at 26°N, Mid‐Atlantic Ridge, is −200 m in diameter, exhibits 50 relief, and covered entirely by precipitates. Eight different types vent solids were recovered from mound submersibles Alvin Mir 1986, 1990, 1991. Detailed petrographic geochemical studies samples their distribution are used to deduce patterns fluid flow seawater/hydrothermal interaction. Geochemical modeling calculations using composition data...
A high‐precision, high‐resolution geologic map explicitly documents relationships between tectonic features and large steep‐sided, sulfide‐sulfate‐silica deposits in the vigorously venting Endeavour hydrothermal field near northern end of Juan de Fuca Ridge. Water depth vent varies from 2220 to 2200 m. Location most massive sulfide structures appears be controlled by intersections ridge‐parallel normal faults other fracture‐fissure sets that trend oblique to, perpendicular overall structural...
The TAG hydrothermal field is a site of major active and inactive volcanic-hosted mineralization in the rift valley slow-spreading Mid-Atlantic Ridge at 26[degree]N. axial high principal locus present magmatic intrusions. contains three main areas past activity: (1) an actively venting high-temperature sulfide mound; (2) two former vent areas; (3) zone low-temperature precipitation Fe Mn oxide deposits. volcanic centers occur intersections between ridge axis-parallel normal faults projected...
The Lucky Strike hydrothermal field occurs in the summit basin of a large seamount that forms shallow center 65 km long ridge segment near 37°N on Mid-Atlantic Ridge. depth and chemistry are influenced by Azores hot spot, this is first Atlantic site found crust dominated spot signature. Multiple vents occur over an area at least 300 m 700 m. Vent morphologies range from flanges chimneys with temperatures 200–212°C, to black smoker up 333°C. Cooler fluids northern have higher chlorinities...
Summary To evaluate the effects of local fluid geochemistry on microbial communities associated with active hydrothermal vent deposits, we examined archaeal and bacterial 12 samples collected from two very different fields: basalt‐hosted Lucky Strike (37°17′N, 32°16.3′W, depth 1600–1750 m) ultramafic‐hosted Rainbow (36°13′N, 33°54.1′W, 2270–2330 fields along Mid‐Atlantic Ridge (MAR). Using multiplexed barcoded pyrosequencing variable region 4 (V4) 16S rRNA genes, show statistically...
The hydrothermal mats, mounds, and chimneys of the southern Guaymas Basin are surface expression complex subsurface circulation patterns. In this overview, we document most frequently visited features area with photographs, temperature measurements, selected geochemical data; many these distinct habitats await characterization their microbial communities activities. Microprofiler deployments on mats sediments show steep thermal gradients at millimeter-scale vertical resolution. Mapping...
A diffusely venting chimney spire from the East Pacific Rise (9 degrees N) was analysed by petrographic thin sectioning and 16S rRNA gene cloning sequencing in parallel, to correlate microbial community composition with mineralogy inferred situ conditions within mineral matrix. Both approaches indicated a zonation of into distinct microhabitats for different bacteria archaea. The thermal gradient porosity consistent distribution bacterial archaeal phylotypes novel phylogenetic lineage...
A quantitative model of transport and chemical reaction is developed to examine the interplay physical processes controlling evolution black smoker chimneys. Diffusion advection yield steady state profiles temperature concentration across a porous wall bound on one side by hydrothermal fluid other seawater. The pressure gradient estimated from dynamics high‐velocity flow inside chimney. Parametric studies reveal importance diffusion driven gradients in activity coefficients resulting strong...
Summary Thermocouple arrays were deployed on two deep‐sea hydrothermal vents at Guaymas Basin (27°0.5′N, 111°24.5′W) in order to measure situ temperatures which microorganisms colonize the associated mineral deposits. Intact sections of three structures that formed around collected after 4 and 72 day deployments (named BM4, BM72 TS72). Archaeal diversity with discreet subsamples across each deposit was determined by polymerase chain reaction amplification 16S rRNA genes. Spatial differences...
Forty‐nine hydrothermal sulfide‐sulfate rock samples from the Endeavour Segment of Juan de Fuca Ridge, northeastern Pacific Ocean, were dated by measuring decay 226 Ra (half‐life 1600 years) in barite to provide a history venting at site over past 6000 years. This dating method is effective for ranging age ∼200 20,000 years old and effectively bridges an gap between shorter‐ longer‐lived U‐series techniques deposits. Results show that active High Rise, Sasquatch, Main fields began least 850,...
Petrologic and geochemical studies of vent solids from the Main Endeavour Field (MEF) High Rise (HRF), Juan de Fuca Ridge, demonstrate that steep‐sided structures characteristic these sites form dominantly by flange growth, combined with diffuse flow through sealed portions structures, incorporation flanges into structures. Geochemical calculations suggest prevalence amorphous silica in deposits is result conductive cooling fluids have high concentrations ammonia. At Endeavour, as...