Extensive volcanic fields on the western Arabian Plate have erupted intermittently over the last 30 Ma following emplacement of the Afar flood basalts in Ethiopia. In an effort to better understand the origin of this volcanism in western Saudi Arabia, we analyzed ³He/⁴He, and He, CO₂ and trace element concentrations...
Harrat Hutaymah is an alkali basalt volcanic field in north-central Saudi Arabia, at the eastern margin of a large Neogene continental, intraplate magmatic province. Lava flow, tephra and spatter cone compositions in the field include alkali olivine basalts and basanites. These compositions contrast with the predominantly tholeiitic, fissure-fed basalts found...
The Franciscan Complex accretionary prism was assembled during an similar to 165-m.y.-long period of subduction of Pacific Ocean plates beneath the western margin of the North American plate. In such fossil subduction complexes, it is generally difficult to reconstruct details of the accretion of continent-derived sediments and to evaluate the...
The factors that control the explosivity of silicic volcanoes are critical for hazard assessment, but are often poorly constrained for specific volcanic systems. Mount Hood, Oregon, is a somewhat atypical arc volcano in that it is characterized by a lack of large explosive eruptions over the entire lifetime of the...
Concentrations of H₂O and CO₂ in olivine-hosted melt inclusions can be used to estimate crystallization depths for the olivine host. However, the original dissolved CO₂ concentration of melt inclusions at the time of trapping can be difficult to measure directly because in many cases substantial CO₂ is transferred to shrinkage...
We present 36 new ⁴⁰Ar-³⁹Ar incremental heating age determinations from the Caribbean Large
Igneous Province (CLIP) providing evidence for extended periods of volcanic activity and suggest a new
tectonomagmatic model for the province’s timing and construction. These new ⁴⁰Ar-³⁹Ar ages for the
Curaçao Lava Formation (CLF) and Haiti’s Dumisseau Formation...
To test the utility of otolith chemical composition as a tool for determining the natal stream of origin for salmon, we examined water chemistry and otoliths of juvenile and adult Chum Salmon Oncorhynchus keta and Coho Salmon O. kisutch from three watersheds (five rivers) in the Norton Sound region of...
Plagioclase ultraphyric basalts (PUBs) have been sampled along most mid-ocean ridges with
ultraslow to intermediate spreading rates. Over the past 40 years, the prevalent models for their origin
assume positive buoyancy of plagioclase in basaltic liquids resulting in selective concentration of
plagioclase phenocrysts by floatation. However, when the global population...
Subduction zone recycling of volatiles (H₂O, Cl, S, F) is controlled by the nature of subducted materials and the temperature-pressure profile of the downgoing slab. We investigate the variability in volatile and fluid-mobile trace element enrichment in the Sunda arc using melt inclusion data from Kawah Ijen and Tambora volcanoes,...
The zebrafish’s potential as a model for human neurobehavioral research appears nearly limitless despite its relatively recent emergence as an experimental organism. Since the zebrafish has only been part of the research community for a handful of decades, pathogens from its commercial origins continue to plague laboratory stocks. One such...