EarthRef.org Digital Archive (ERDA)
Development and Maintenance by the EarthRef.org Database Team

Detailed File Information (#1)
The Seamount Catalog Database Interface
File Name koppers.sc.poster.ai
Data Type poster
Computer Program Adobe Illustrator CS2
File Size 2.29 MB - 1 file
Expert Level College and Introduction to Science
Contributor Anthony A.P. Koppers
Source http://earthref.org/SBN
Resource Matrix The Formation of Seamounts
Description
The Seamount Catalog carries a series of key products that will serve the SBN network, including access to a wide range of map products that range from simple downloadable bathymetric maps to the XYZ NetCDF grids and the original data files (multibeam, sidescan) that may be recombined with other data sets to upgrade or re-plot the maps, according to the users own needs and expertise. The Seamount Catalog features an easy-to-use search interface that displays available data for download and some vital statistics for more than 1800 seamounts, such as summit depth, seamount length/width and volume, shape, elongation, age, ocean floor depth and age, multibeam coverage, etc.
Detailed File Information (#2)
The EarthRef.org Web Portal
File Name koppers.earthref.poster.ai
Data Type poster
Computer Program Adobe Illustrator CS2
File Size 1.37 MB - 1 file
Expert Level College and Introduction to Science
Contributor Anthony A.P. Koppers
Source http://earthref.org
Description
The EarthRef.org website originally has been developed as the host website for GERM (the Geochemical Earth Reference Model initiative), but it is now a very substantial website for a wide range of Earth science data that spans from geochemistry to paleomagnetism to geochronology and more. A variety of EarthRef.org tools and databases are immediately available to its users: The EarthRef Address Book is a much used directory for Earth scientists address information (~2,000 registered users) that is frequently visited by users using web search engines such as Google. The Earthref Reference Database includes a very substantial number (~95,000) of publications, archived with complete reference information, abstracts and, in many cases, Microsoft Excel files of tables and appendices. Finally, the EarthRef Digital Archive is a fully functional database that archives any digital object with a critical number of metadata to make it efficiently searchable by researchers, teachers and students. You can upload your own data files in this archive. On top of these common tools, the EarthRef.org Web Portal functions as the umbrella web site for the GERM, MagIC, SBN and ERESE initiatives.
Detailed File Information (#3)
Introduction to the First SBN Workshop by Hubert Staudigel and Anthony Koppers
File Name sbn.introduction.4.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 1.21 MB - 1 file
Expert Level College and Introduction to Science
Contributor Anthony A.P. Koppers
Source http://earthref.org/SBN
Description
In this Powerpoint presentation the goals for the First SBN Workshop are outlined by the conveners, including an overview of the scientific program, the rational for the breakout sessions, and a short summary of all poster presentations. This introduction is ended with an introduction to the online Seamount Catalog.
Detailed File Information (#4)
SBN Workshop Automatic Powerpoint Advertisement
File Name sbn.advertisement.3.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 260.00 KB - 1 file
Expert Level College and Introduction to Science
Contributor Anthony A.P. Koppers
Source http://earthref.org/SBN
Description
In this Powerpoint the Seamount Biogeosciences Network (SBN) is introduced by listing the primary goals and duration of the project. This presentation also includes the people who are involved and the program for the First SBN Workshop being hold at the Scripps Institution of Oceanography in La Jolla at the end of March 2006.
Detailed File Information (#5)
Hotspot and Non-Hotspot Origins for the Age-Distribution of Volcanism in Pacific Seamount
File Name duncan.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 15.61 MB - 1 file
Expert Level College and Introduction to Science
Contributor Robert A. Duncan
Source No source
Resource Matrix The Formation of Seamounts
Description
The Hawaiian-Emperor seamount chain is the type example of an age-progressive, hotspot-generated intraplate volcanic lineament. However, our current knowledge of the age distribution within this province is based largely on radiometric ages determined several decades ago. In this keynote presentation during the First SBN Workshop, Bob Duncan shows that major improvements in instrumentation, sample preparation methods and new material obtained by recent drilling warrant a re-examination of the age relations among the older Hawaiian volcanoes. Plateau and isochron age determinations (40Ar-39Ar incremental heating method) on whole rocks and feldspar separates from deep drilling sites (ODP Leg 197) in the Emperor seamounts, together with similarly modern data from dredged rocks from volcanoes near the prominent bend (47-49 Ma) in the lineament (Sharp and Clague, 2002), confirm the overall trend is increasing volcano age from south to north, consistent with the hotspot model. There are important departures from the earlier reported simple linear age progression, which are related to changes in Pacific plate motion and the rate of southward motion of the Hawaiian hotspot. Recent studies of dredged volcanic rocks from the Louisville seamount chain (Koppers et al. 2004) show many of the same features within an overall, age-progressive trend, illustrating the utility of a hotspot reference frame adjusted for slowly advected mantle plumes (Steinberger and O'Connell, 1998).
Detailed File Information (#6)
Cultivation of novel marine Fe-oxidizing bacteria from the Loihi Seamount
File Name emerson.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 15.87 MB - 1 file
Expert Level College and Introduction to Science
Contributor David Emerson
Source No source
Resource Matrix The Formation of Seamounts
Description
Iron is one of the most abundant energy sources for lithotrophic organisms on Earth, yet very few cultures exist of Fe-oxidizing bacteria (FeOB) that can utilize Fe(II) as a sole energy source at circumneutral pH. Much of the work that has been done on FeOB is from freshwater habitats, so marine FeOB are even less well understood. In his keynote presentation for the First SBN Workshop, Dave Emerson shows that the advent of a variety of molecular techniques now make us much less dependent on culturing microbes to understand their diversity, abundance and role in the environment. At the same time those techniques underscore the importance of having representative isolates available in culture that can provide context for the interpretation of molecular methods. The culture of FeOB represents a special case in point, where specialized culturing conditions that mimic the host environment are essential to achieving success. We have focused studies on the extensive mats of (FeOB) at the summit of the Loihi Seamount (1100m deep) that are associated with low to intermediate temperature (10° to 65°C) vents whose fluids contain 10's to 100's of µM Fe(II). The mats contain 107 to 108 bacterial cells/cc and the morphology of the Fe-oxides is indicative of biological origins. We have isolated an obligately lithotrophic FeOB from Loihi, Mariprofundus ferroxydans. Phylogenetic analysis shows that M. ferroxydans is the first cultured representative of a proposed new Bacterial division, the zeta-Proteobacteria. Molecular evidence from Loihi, based on clone libraries and terminal restriction length polymorphism (tRFLP) analysis of 16S rRNA genes, indicate this lineage of FeOB is the most abundant inhabitant in the Fe-mats. Furthermore, this lineage is ubiquitous at diverse Fe(II)-driven ecosystems at hydrothermal vent sites throughout the Pacific.
Detailed File Information (#7)
The Global Distribution of Seamounts from Ship Depth Soundings and Satellite Altimetry
File Name sandwell.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 26.18 MB - 1 file
Expert Level College and Introduction to Science
Contributor David Sandwell
Source No source
Resource Matrix The Formation of Seamounts
Description
Seamounts are active or extinct undersea volcanoes rising more than 1 km above the abyssal plain. They represent a significant fraction of the volcanic extrusive budget for oceanic seafloor and their distribution gives information about spatial and temporal variations in intraplate volcanic activity. In addition, they sustain important ecological communities, determine habitats for fish, and act as obstacles to currents, enhancing tidal energy dissipation and ocean mixing. In this keynote presentation for the First SBN Workshop, Dave Sandwell explains that for all these reasons, it is important to locate and characterize seamounts. Two approaches are used to map the global seamount distribution. Depth sounds from single- and multi-beam echo sounders can provide the most detailed maps with up to 200 m horizontal resolution. However, soundings from the 5600 publicly available cruises sample only a small fraction of the ocean floor. Satellite altimeter measurements of the marine gravity field can detect sea-mounts taller than about 2 km and such studies have produced seamount catalogues holding almost 15,000 seamounts . Recent retracking of the radar altimeter waveforms to improve the accuracy of the gravity field has resulted in a two-fold increase in resolution. We predict that 45,000 smaller seamounts remain uncharted. Future altimetry missions could improve on resolution and decrease noise levels even further, allowing for an even larger number of small (1-1.5 km) seamounts to be detected. Mapping the complete global distribution will help constrain the hotly-debated models of seamount formation as well as aid in understanding of marine habitats and deep ocean circulation.
Detailed File Information (#8)
Microbial Community Characterization at Seamounts
File Name tebo.introduction.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 1001.00 KB - 1 file
Expert Level Graduate School
Contributor Bradley Tebo
Source No source
Resource Matrix The Formation of Seamounts
Description
This is an introduction talk by Brad Tebo on Microbial Community Characterization at Seamounts session during the First SBN Workshop. In this introduction whole cell and cell extract assays are introduced to answer the question on what micro-organisms are present on seamounts, how many, what they are doing and how fast. This introduction is concluded by listing the current approaches in answerring these questions.
Detailed File Information (#9)
The history of seamounts that reach the sea surface
File Name winterer.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 53.76 MB - 1 file
Expert Level College and Introduction to Science
Contributor Jerry Winterer
Source No source
Resource Matrix The Formation of Seamounts
Description
Only a tiny proportion (a few percent) of seamounts attain heights that bring their summits above sealevel where a post-volcanic history more complicated than mere subsidence can develop. Nearly all of these island volcanoes erupt on lithosphere older than 5 m.y. and most develop on crust at least several tens of m.y. old. In this keynote presentation for the First SBN Workshop Jerry Winterer reviews the history of seamounts and how they come to forming reefs, crags, barriers, atolls and guyots. Repeated fluctuations of sealevel, particularly those of the magnitude a frequency of those in the Pleistocene, result in the formation of an atoll through rainwater dissolution, rather than the classical Darwin model of atoll formation. Few pre-Neogene atolls are known, possible because sealevel fluctuations were of insufficient amplitude (100 m) and duration (100 ky) to permit the necessary rainwater dissolution.
Detailed File Information (#10)
Seamount Communities and Pelagic Interfaces: A Tale of Two Seamounts
File Name wishner.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 16.53 MB - 1 file
Expert Level College and Introduction to Science
Contributor Karen Wishner
Source No source
Description
What happens when a strong pelagic chemical interface intersects a seamount? How do responses of zooplankton and benthos differ and what unique interactions are created by the seamount situation? We have opportunistically explored two examples of this phenomenon and in this keynote presentation from Karen Wishner during the First SBN Workshop two seamounts are discussed as examples, one in the eastern tropical Paficif (Volcano 7) and one in the Caribbean Sea near Grenada (Kick'em Jenny). The first deals with a seamount penetrating into the oxygen minimum zone; the second deals with hydrothermal vent effluent in a volcanic crater. In both cases, the chemical gradient seems to be spatially (horizontally) extensive, although varying in depth over time, and delineates a zone physiologically hostile to many animal taxa. This has created some unusual biological distributions.
Detailed File Information (#11)
Deepsea Seamounts in the Southwest Pacific: Fisheries and Conservation
File Name clark.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 22.08 MB - 1 file
Expert Level College and Introduction to Science
Contributor Malcolm R. Clark
Source No source
Description
The world¿s major marine fisheries have generally taken place on the relatively narrow and shallow continental shelf. But over the last 2-3 decades deepwater trawl fisheries have developed on the upper continental slope and offshore seamounts, and are an important component of commercial fisheries in the Southwest Pacific. These fisheries include well-known species like orange roughy, oreos, cardinalfish and alfonsino. New Zealand and Australian catches of these species total several thousand tonnes per year, with orange roughy being the largest fishery at about 20,000 tons. In this keynote lecture for the First SBN Workshop Malcolm Clark details the current status on seamount fisheries, the amount of overfishing, fisheries management and attempts to habitat conservation -- all with an emphasis on the EEC of New Zealand.
Detailed File Information (#12)
A review of physical oceanographic processes at seamounts
File Name lavelle.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 7.85 MB - 1 file
Expert Level Graduate School
Contributor J William Lavelle
Source No source
Resource Matrix Waves and Tides
Description
Ocean conditions at seamounts depend on topography, on ambient stratification, on latitude, and on the strength and periodicity of flows that sweep each object. Geometrical considerations include seamount summit size, shape, and proximity to the sea surface, as well as flank slope and overall water depth. Flow impinging on a seamount can be steady, quasi-steady as might be caused by meso-scale eddies, oscillatory with tidal flows being prominent, or intermittent as in wind-driven flows with inertial response. A wide range of flow, hydrographic, and turbulent energy responses at and around seamounts is consequently possible. In this keynote presentation by William Lavelle during the First SBN Workshop the basic physical oceanographic features at seamounts are identified and related to topographic and environmental factors. Emphasis is given to numerical model results. Steady and tidally forced circulation both can lead to time-mean flows that are trapped around the seamount summit. In the case of tidal forcing, a short recirculation cell typically drives flow downward toward and radially outward from the center of the seamount apex. That flow is related to time-mean temperature anomalies, i.e. cold domes, that are often observed above the summit.
Detailed File Information (#13)
Introduction to Benthic Ecology and Oceanographic Controls
File Name mohn.introduction.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 631.00 KB - 1 file
Expert Level College and Introduction to Science
Contributor Christian Mohn
Source No source
Resource Matrix Ocean Currents
Description
In this introduction of one of the keynote sessions during the First SBN Workshop, Christian Mohn summarizes what the important ingredients are to describe the dominant physical processes and their interactions in the water column around seamounts.
Detailed File Information (#14)
Variability in microbial mat communities from the pre- and post-eruption Loihi volcano
File Name moyer.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 14.77 MB - 1 file
Expert Level College and Introduction to Science
Contributor Craig L. Moyer
Source No source
Resource Matrix Biomediation of Lavas
Description
Loihi Seamount is an active submarine volcano that marks the southernmost extent of the Hawaiian hot-spot. Loihi rises over 3000 meters from the seafloor and summits nearly 1000 meters below sea level. Hydrothermal activity was discovered at Loihi in 1987, yielding diffuse vent effluent (Tmax ~37C) with associated high CO2 and Fe(II) concentrations and luxuriant microbial mats near the summit of the volcano. The Seamount erupted in 1996 forming a new 300m deep caldera (Pele's Pit) with hydrothermal venting up to 200̊C. Pele's Pit now contains multiple hydrothermal vents with hydrothermal fluids rang-ing from 8-65C with concentrations of Fe(II) between 50 and 750¿M. Community fingerprints from over 50 microbial mat samples collected from Loihi Seamount from 1993 to 2004, with temperatures ranging from ambient (4C) up to ~200C, were analyzed using cluster analysis of terminal restriction fragment length polymorphisms (T-RFLP) coupled with traditional clone library and sequence analysis. In this keynote presentation for the First SBN Workshop Craig Moyer show cases the spatial and temporal variabilities in the microbial communities as observed before and after an important volcanic episode at Loihi.
Detailed File Information (#15)
The Supply of Food and Larvae to Benthic Seamount Communities
File Name mullineaux.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 6.80 MB - 1 file
Expert Level College and Introduction to Science
Contributor Lauren Mullineaux
Source No source
Description
Physical processes at seamounts influence the transport and retention of living and non-living particles. When fluxes of particles such as small plankton or detritus are enhanced near a seamount, the food supply to benthic organisms is increased. When particles such as larvae of benthic organisms are retained near a seamount, their recruitment into the natal populations may be increased, but their exchange with other seamount populations will be limited. Lauren Mullineaux explores how the physical processes at seamounts appear to influence food supply to the populations of suspension-feeding corals and sponges that live there in dense aggregations in this keynote presentation for the First SBN Workshop. She also reviews the evidence for retention of larvae and other particles near seamounts and considers the implications of larval retention for population connectivity and endemism of benthic species.
Detailed File Information (#16)
Physical characterisation and biological classification of New Zealand seamounts
File Name pile.discussion.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 1.88 MB - 1 file
Expert Level College and Introduction to Science
Contributor Adele J PIle
Source No source
Description
In this discussion item for the First SBN Workshop Adele Pile highlights recent research that performed a statistical analyses to classify all seamounts in the New Zealand's EEC and its proximity. In this analysis 475 seamounts were included that gave 12 groupings based on group average hierarchical clustering using an euclidean distance metric. The most important parameters turn out to be the variable depth at the seamount base, depth at peak, elevation and distance to continental shelf.
Detailed File Information (#17)
Fe-Microbial Mats at Vailulu'u
File Name templeton.discussion.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 2.56 MB - 1 file
Expert Level Graduate School
Contributor Alexis Templeton
Source No source
Resource Matrix Biomediation of Lavas
Description
In this discussion item during the First SBN Workshop Alexis Templeton summarizes the recent data on microbial mats collected from the crater and crater rim of the Vailulu'u underwater volcano. The aim of these studies are to understand the microbial interactions with the fresh basalt as erupted over the last 4 years on top of the Nafanua volcanic cone inside the crater.
Detailed File Information (#18)
Geochemical Fluxes and the Role of Seamounts in Ventilating the Oceanic Crust
File Name wheat.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 4.25 MB - 1 file
Expert Level College and Introduction to Science
Contributor C. Geoffrey Wheat
Source No source
Resource Matrix Hydrothermal Systems
Description
Ridge flank hydrothermal systems (RFHS) remove most of the convective heat loss from the oceanic crust. This heat loss and the associated fluid flow is almost completely confined to seamounts and guided by faults, because the permeability of basaltic basement is orders of magnitude greater than that of overlying sediment. The magnitude of this flow is the largest crustal fluid flux in the oceans, but it is only ~66% of the riverine water flux. Yet even a small chemical anomaly, resulting from water-rock interactions or from diffusive exchange with the overlying sediment, coupled with this amount of flow could result in a chemical flux that is important (defined as >10%) to global budgets. For example, the entire riverine influx of Mg could be deposited within the oceanic crust in the form of secondary clays (primarily smectites), given this vast flow of seawater through the crust and only a 0.3% decrease in the seawater concentration. Although the calculated thermal and fluid fluxes from RFHS are fairly well con-strained, chemical fluxes from RFHS are not well constrained because of the paucity of sites sampled to date. In this keynote presentation during the First SBN Workshop Geoffrey Wheat summarizes the recent studies that deal with geochemical fluxes from seamounts and their impact on global geochemical budgets.
Detailed File Information (#19)
The Biota of Vailulu'u Seamount in the Samoan Archipelago
File Name young.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 38.58 MB - 1 file
Expert Level College and Introduction to Science
Contributor Craig Young
Source No source
Description
Vailulu'u is the active seamount on the hotspot at the Eastern end of the Samoan volcanic chain, and has been the focus of two research cruises in April and June 2005 using the Pisces V submersible. The objectives of biological studies include the macrobiological and microbiological exploration of biota in a wide range of settings, including a newly formed volcanic cone, Nafanua forming a pronounced summit in the crater of Vailulu¿u, a series of hydrothermal vents up to 80¿C, and settings inside and outside the crater. In this keynote presentation for the First SBN Workhop Craig Young lays out all the evidence for a widely diverse group of biota as observed for Vailulu'u. In particular, he describes Eel City that has been occupied a large group of the synaphobranchid eel Dysommina rugosa.
Detailed File Information (#20)
CARD-FISH approaches for characterizing endolithic rock-hosted microbial populations
File Name edwards.mov
Data Type presentation
Computer Program Quicktime
File Size 20.57 MB - 1 file
Expert Level Graduate School
Contributor Katrina J Edwards
Source No source
Resource Matrix Biomediation of Lavas
Description
In this keynote presentation for the First SBN Workshop Katrina Edwards discusses the process of basalt-weathering as promoted by endolithic microbes that colonize volcanic rocks at seamounts and on the flanks of mid-ocean ridge spreading centers at and below the seafloor. She hypothesizes that the activities of autotrophic Fe- and S-oxidizing prokaryotes play important roles in the initial colonization and weathering of ocean crust. This process results in (1) the development of sharp redox gradients associated with seafloor-exposed surfaces, or subseafloor surfaces exposed to recirculating fluids along fractures, and (2) a flux of fresh organic C to ridge flanks that may be used for respiration by endolithic heterotrophic (including Fe- and S-reducing) prokaryote communities. The objectives of these kind of studies are to define this succession on basalt during the aging/weathering process, and to identify and quantify key constituents of these communities and understand the physical and mineralogical associations between microbes and dissolution features and secondary weathering products.
Detailed File Information (#21)
Seamounts Enhance the Global Influence of Ridge-flank Hydrothermal Circulation
File Name fisher.ppt
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 3.94 MB - 1 file
Expert Level College and Introduction to Science
Contributor Andrew Fisher
Source No source
Resource Matrix The Formation of Oceanic Crust
Description
Seamounts are recognized to influence global hydrothermal fluxes in at least three ways. First, volcanically active seamounts, generally located close to active spreading centers and/or associated with hotspot magmatism, are often hydrothermally active. These systems may vent both high-temperature and low-temperature hydrothermal fluids, although these fluxes are likely to be small compared to those at spreading centers (simply because spreading centers are spatially more common). Second, volcanically inactive seamounts provide access points for entry and exit of ridge-flank hydrothermal fluids, those extracting lithospheric heat on a regional basis across much of the seafloor. Fluid fluxes associated with these systems are much larger than those at spreading centers (probably by a factor of 100-1000), and the heat output of ridge-flank systems is also larger than that of systems at spreading centers, but the influence of ridge-flank circulation on global geochemical fluxes varies species by species and remains less certain. Third, volcanically inactive seamounts may host isolated hydrothermal circulation systems associated with local basement relief. In his keynote presentation for the First SBN Workshop, Andrew Fisher shows that a recent analysis of the dynamics of these systems suggests that they may result in globally-significant fluid fluxes (smaller than conventional ridge-flank fluxes but greater than those at spreading centers or volcanically-active seamounts). The primary thermal influence of these isolated, seamount circulation systems is likely to be local, but they may have biased measurements of seafloor heat flow during earlier studies (particularly in cases where the presence of seamounts was unknown), and their influence on geochemical fluxes remains uncertain. The influence of all of these systems on subseafloor microbiology also remains largely unknown and a focus of much ongoing research.
Detailed File Information (#22)
OASIS - An Integrated Study of Oceanic Seamounts
File Name christiansen.pdf
Data Type presentation
Computer Program Adobe Acrobat
File Size 3.67 MB - 1 file
Expert Level College and Introduction to Science
Contributor Bernd Christiansen
Source No source
Description
OASIS is a research project which describes the functioning characteristics of seamount ecosystems. It is funded by the European Union and involves 9 institutions from 5 European countries. In this keynote presentation for the First SBN Workshop, Bernd Christiansen describes OASIS' holistic approach to investigate seamount ecosystems integrates hydrographic, biogeochemical and biological information. Based on two case studies, OASIS yields an advanced mechanistic under-standing of the processes characterizing seamount ecosystems, and their influence on the surrounding ocean. The scientific results, condensed in conceptual and mass balanced ecosystem models, are applied to outline a model management plan as well as site-specific management plans for the seamounts investigated.
Detailed File Information (#23)
Tumult in Samoa
File Name hart.staudigel.ppt
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 24.90 MB - 1 file
Expert Level College and Introduction to Science
Contributor Hubert Staudigel
Source No source
Resource Matrix The Formation of Seamounts
Description
Is the Samoan volcanic chain the result of a hotspot or plume? Or not? Argued for decades, the discovery of volcanic activity at Vailulu'u seamount certainly supports the hotspot/plume model. Vailulu'u anchors the east end of the Samoan chain, much as Loihi anchors the Hawaiian chain's east end. The Samoan volcanic centers get older to westward, and are aligned with Pacific plate motion. This trend of aging is broken only by the voluminous young rejuvenated volcanism on Savai¿i, a large island some 370 km west of Vailulu'u. Volcanism all along the chain has characteristic and unusual Sr, Nd, and Pb isotopic signatures, affirming a common Samoan pedigree. However, in this keynote presentation during the First SBN Workshop Stan Hart and Hubert Staudigel discuss a completely different aspect of Vailulu'u seamount, namely its summit crater which hosts active hydrothermal venting, with a power output of some 600 megawatts (measured by a dye release experiment). The crater waters are remarkably high in manganese, iron, helium-3 and particulates, and a resurgent volcanic cone ~300 meters high has grown in the crater since 2001. The hydrothermal power drives a remarkably complex and dynamic circulation system in and surrounding the summit crater.
Detailed File Information (#24)
Henry Seamount at the western Canary Islands
File Name sbn.poster.kluegel.hansteen.pdf
Data Type poster
Computer Program Acrobat Reader 5.0
File Size 3.61 MB - 1 file
Expert Level College and Introduction to Science
Contributor Andreas Kluegel
Source No source
Resource Matrix The Formation of Seamounts
Description
Henry Seamount is a 660-m-high circular structure that rises from 3700 m deep seafloor southeast of El Hierro, close to the present location of the Canary hotspot. Because of its morphology and thick sediment coverage the seamount is interpreted as a comparatively old and passive volcano. A dredging campaign in 2005, however, yielded some volcanic rocks, massive barite and also well-preserved shells of vesicomyid clams that are indicative of active fluid flow. It appears that the seamount is or was recently discharging warm fluid, the driving force being either volcanic activity from Henry Seamount itself or heating of the underlying crust by the nearby hotspot.
Detailed File Information (#25)
Seamount ecology
File Name stocks.pps
Data Type presentation
Computer Program Microsoft Powerpoint 2003
File Size 8.39 MB - 1 file
Expert Level College and Introduction to Science
Contributor Karen Stocks
Source No source
Description
One of the reasons why seamounts have been the focus of substantial ecological research is that they are thought to represent unique communities, supporting assemblages of species that are distinct from the surrounding seafloor. In this keynote presentation during the First SBN Workshop, Karen Stocks summarizes a literature review to examine three aspects of community structure ¿ biodiversity, endemism, and biogeographic affinities ¿ to ask how distinct seamount communities really are. The topic has clear management implications, for example determining whether marine protected areas on seamounts are needed and how they should be placed. Describing and comparing seamount community structure also has theoretical implications: once patterns are determined, they can be compared to predictions from various biogeographic theories to understand how these theories may be useful for predicting from the handful of studied seamounts to the tens of thousands of unknown ones.
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