Radiometric ages (K-Ar and ⁴⁰Ar-
³⁹Ar methods) have been determined on dredged
volcanic rocks from seven of the New England
Seamounts, a prominent northwest-southeast trending
volcanic lineament in the northwestern
Atlantic Ocean. The ⁴⁰Ar-³⁹Ar total fusion and
incremental heating ages show an increase in
seamount construction age from southeast to...
The summit crater of Vailulu’u Seamount, the youngest volcano in the Samoan chain, hosts an active
hydrothermal system with profound impact on the ocean water column inside and around its crater (2 km
wide and 407 m deep at a 593 m summit depth). The turbidity of the ocean water...
Seamounts are a ubiquitous feature of the seafloor but relatively little is known about their internal structure. A seamount preserved in the Franciscan mélange of California suggests a sequence of formation common to all seamounts. Field mapping, geophysical measurements, and geochemical analyses are combined to interpret three stages of seamount...
We examine the thermal effects of seamount subduction. Seamount subduction may cause transient changes in oceanic crust hydrogeology and plate boundary fault position. Prior to subduction, seamounts provide high‐permeability pathways between the basaltic crustal aquifer and overlying ocean that can focus fluid flow and efficiently cool the oceanic crust. As...
We examine the thermal effects of seamount subduction. Seamount subduction may cause transient changes in oceanic crust hydrogeology and plate boundary fault position. Prior to subduction, seamounts provide high-permeability pathways between the basaltic crustal aquifer and overlying ocean that can focus fluid flow and efficiently cool the oceanic crust. As...
We present multiple lines of evidence for years to decade-long changes in the location and
character of volcanic activity at West Mata seamount in the NE Lau basin over a 16 year period, and a hiatus
in summit eruptions from early 2011 to at least September 2012. Boninite lava and...
We present multiple lines of evidence for years to decade-long changes in the location and
character of volcanic activity at West Mata seamount in the NE Lau basin over a 16 year period, and a hiatus
in summit eruptions from early 2011 to at least September 2012. Boninite lava and...
Full Text:
West Mata seamount, NE Lau basin: 1996-2012
Eruptive modes and hiatus of volcanism at West Mata
We present multiple lines of evidence for years to decade-long changes in the location and
character of volcanic activity at West Mata seamount in the NE Lau basin over a 16 year period, and a hiatus
in summit eruptions from early 2011 to at least September 2012. Boninite lava and...
Volcanic samples collected with the Monterey Bay Aquarium Research Institute's ROV Tiburon from eight seamounts at the continental margin offshore central to southern California comprise a diverse suite of mainly alkalic basalt to trachyte but also include rare tholeiitic basalt and basanite. All samples experienced complex crystal fractionation probably near...
Cobb hotspot, currently located beneath Axial seamount on the Juan de Fuca ridge, has the temporal
but not the isotopic characteristics usually attributed to a mantle plume. The earlier volcanic products of
the hotspot, from eight volcanoes in the Cobb-Eickelberg seamount (CES) chain, show a westward age
progression away from...
