Reading through this issue of Oceanography, it will become
apparent that researchers in different disciplines see their
seamounts in quite different ways. The term seamount has been
defined many times (e.g., Menard, 1964; Wessel, 2001; Schmidt and
Schmincke, 2000; Pitcher et al., 2007; International Hydrographic
Organization, 2008; Wessel et al.,...
Lō`ihi Seamount defines the volcanically active, leading edge in the Hawaiian hotspot chain. It is located on the submarine flank of Mauna Loa, 30 km south of the island of Hawai`i. Lō`ihi’s summit is at 975-m water depth (Pisces Peak), and the seamount has a pronounced southern rift that extends...
Seamounts are ubiquitous features of the seafloor that form part of the fabric of oceanic crust. When a seamount enters a subduction zone, it has a major affect on forearc morphology, the uplift history of the island arc, and the structure of the downgoing slab. It is not known, however,...
We report new ⁴⁰Ar/³⁹Ar ages for the oldest Pacific oceanic floor at Ocean Drilling Program Site 801C in the Pigafetta basin and Site 1149D close to the Izu-Bonin subduction zone in the Nadezhda basin. These ages were determined by applying high-resolution incremental heating experiments (including 15–30 heating steps) to better...
Many disciplines of geochemistry have no data reporting standards, and their use of metadata is inadequately developed. This presents problems to the quality of the published science, and it limits the utility of computers in data analysis and the exploitation of Information Technology (IT). We discuss problems of data and...
On 3 April 2001, a 20 kg point source of fluorescein dye was released 30 m above the bottom of the active summit caldera of Vailulu’u submarine volcano, Samoa. Vailulu’u crater is 2000 m wide and at water depths of 600–1000 m, with the bottom 200 m completely enclosed; it...
In this study we present 42 new ⁴⁰Ar/³⁹Ar incremental heating age determinations updated age progression for the Louisville seamount trail. Louisville is the South Hawaiian‐Emperor seamount trail, both trails representing intraplate volcanism (~80 Ma to present) and being examples of primary hot spot lineaments. Our age‐progressive trend from 71 to...
Estimates of the relative motion between the Hawaiian and Louisville hot spots have consequences
for understanding the role and character of deep Pacific-mantle return flow. The relative motion between
these primary hot spots can be inferred by comparing the age records for their seamount trails. We report
⁴⁰Ar/³⁹Ar ages for...
Estimates of the relative motion between the Hawaiian and Louisville hot spots have consequences
for understanding the role and character of deep Pacific-mantle return flow. The relative motion between
these primary hot spots can be inferred by comparing the age records for their seamount trails. We report
⁴⁰Ar/³⁹Ar ages for...
Lau Basin basalts host an array of geochemical signatures that suggest incorporation of enriched mantle source material often associated with intraplate hotspots, but the origin of these signatures remain uncertain. Geochemical signatures associated with mantle material entrained from the nearby Samoan hotspot are present in northwest Lau Basin lavas, and...
Coring/logging data and physical property measurements from International Ocean Discovery Program Expedition 349 are integrated with, and correlated to, reflection seismic data to map seismic sequence boundaries and facies of the central basin and neighboring regions of the South China Sea. First-order sequence boundaries are interpreted, which are Oligocene/Miocene, middle...
Combined analyses of deep tow magnetic anomalies and International Ocean Discovery Program Expedition 349 cores show that initial seafloor spreading started around 33 Ma in the northeastern South China Sea (SCS), but varied slightly by 1-2 Myr along the northern continent-ocean boundary (COB). A southward ridge jump of ∼20 km...
Estimates of the relative motion between the Hawaiian and Louisville hot spots have consequences
for understanding the role and character of deep Pacific-mantle return flow. The relative motion between
these primary hot spots can be inferred by comparing the age records for their seamount trails. We report
⁴⁰Ar/³⁹Ar ages for...
The volcanic origin of the Samoan archipelago can be explained by one of three models, specifically, by a hot spot forming over a mantle plume, by lithospheric extension resulting from complex subduction tectonics in the region, or by a combination of these two processes, either acting sequentially or synchronously. In...
Submersible exploration of the Samoan hotspot revealed a new, 300-m-tall, volcanic cone, named Nafanua, in the summit crater of Vailulu’u seamount. Nafanua grew from the 1,000-m-deep crater floor in <4 years and could reach the sea surface within decades. Vents fill Vailulu’u crater with a thick suspension of particulates and...
The Sr, Nd, and Pb isotopic compositions of five Cretaceous guyots (Limalok, Lo-En, Wodejebato, MIT, and Takuyo-Daisan) within the West Pacific Seamount Province (WPSP) indicate that they originated from geochemically enriched mantle sources. They are characterized by large isotopic variations in Pb (²⁰⁶Pb/²⁰⁴Pb = 18.58-19.80, ²⁰⁷Pb/²⁰⁴Pb = 15.55-15.68, and ²⁰⁸Pb/²⁰⁴Pb...
Vailulu’u seamount is an active underwater volcano that marks the end of the Samoan hotspot trail (Hart et al., 2000). Vailulu’u has a simple conical morphology (Figure 1) with a largely enclosed volcanic crater at relatively shallow water depths, ranging from 590 m (highest point on the crater rim) to...
Seamounts are windows into the deep Earth that are helping to
elucidate various deep Earth processes. For example, thermal and mechanical
properties of oceanic lithosphere can be determined from the flexing of oceanic
crust caused by the growth of seamounts on top of it. Seamount trails also are
excellent recorders...
Seamount research, more often than not,
is carried out by highly specialized science
teams with narrowly focused science objectives.
As a result, different seamount science
disciplines often do not collaborate or are
not even aware of each other. However, it is
obvious that interdisciplinary collaboration
is the most successful approach...
Vailulu'u Seamount is identified as an active volcano marking the current location of the Samoan hotspot. This seamount is located 45 km east of Ta'u Island, Samoa, at 169°03.5′W, 14°12.9′S. Vailulu'u defines the easternmost edge of the Samoan Swell, rising from the 5000‐m ocean floor to a summit depth of...