Geothermal

2016 American Samoa Energy Action Plan

Document Overview The 2016 American Samoa Energy  Action Plan outlines actions being taken to reduce American Samoa’s petroleum consumption. It describes the four near-term strategies selected by the American Samoa Renewable Energy Committee (ASREC) during action-planning workshops conducted in May 2016, and describes the steps that will need to be taken to implement those strategies. In August 2016, following the action-planning workshops, ASREC adopted a goal of having 50% of American Samoa’s energy come from renewable energy resources by 2025 and 100% by 2040. All of the strategies in this action plan support those targets. This 2016 Energy Action Plan ...
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Detecting Microseismic Activity in American Samoa with Surface and Deep Borehole Stations

M. Boese,  International Earth Sciences IESE Ltd., 29 East Street, Auckland 1010, New Zealand and T. Bodell, American Samoa EPA, PO Box 8019, Pago Pago, American Samoa 96799, American Samoa carolin.boese@iese.co.nz   Download Complete Report ABSTRACT American Samoa is located at the eastern end of a ~500 km-long chain of islands formed by hotspot volcanism. The original shield volcano edifices of the islands are formed from submarine volcanoes between 5 Ma to present. Various theories explaining the origin of widespread recent and historic rejuvenated volcanism throughout the Samoa chain are based on limited seismic and geochemical data from the surface. This paper presents the ...
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Tutuila Holocene Rift Zone Phase 3 Geothermal Exploration

This report presents the results of geothermal temperature gradient hole (TGH) drilling on Tutuila, American Samoa. The TGH drilling was the third of three phases of geothermal resource exploration conducted by Geologica Geothermal Group Inc. (GEOLOGICA) in American Samoa between 2013 and 2016 for the purposes of evaluating the potential of geothermal power generation. The initial geothermal exploration included evaluation of available geoscientific data and a surface reconnaissance (Phase 1) which focused further exploration on the Holocene Rift Zone (HRZ) of Tutuila. This was followed by geological, geophysical and geochemical investigations, conceptual modeling of a possible geothermal system, and drilling ...
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Geothermal Exploration Update

all of the core samples (in storage), from two x 2000 ft boreholes A core drilling campaign was successful in measuring the thermal gradient in the upper 2,200 feet of the youngest volcanic rift zone of Tutuila.  Temperatures of 1.5 Degrees Centigrade per 100 feet of depth are below the gradient considered feasible for commercial development of 3 degrees centigrade per 100 feet. close-up of the samples Analysis of the core samples confirmed that the Tafuna Leone lowlands are created from a series of volcanic eruptions occurring approximately every 2,000 years over a period greater than 10,000 years and less ...
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Phase 2 Evaluation of the Geothermal Resource Potential of Tutuila Island, American Samoa

Executive Summary The 2nd phase of geothermal exploration on the island of Tutuila included a magnetotelluric (MT) survey of subsurface resistivity, additional soil gas measurements, estimates for the ages of the most recent volcanism, and an evaluation of lineaments previously identified by LiDAR using aerial photography. The background of this scope of work is described in the Preliminary Evaluation of the Geothermal Resource Potential of Tutuila Island, American Samoa (Geologica, 2013) and Interim Evaluation of the Geothermal Resource Potential of American Samoa (Interim Report; Geologica, 2014) which identified and further confirmed the potential for a geothermal resource in the north-northwest ...
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Geothermal Investigation is Moving Forward

3D Simulation of Geologic Conditions of the NNW Rift Zone of Tutuila, American Samoa (Courtesy of University of Hawaii, 2014) July, 2014 Over the past year the American Samoa Power Authority (ASPA), has procured the services of scientists and engineers to explore new groundwater and geothermal energy resources. Specialized aerial surveying, geologic mapping, water, rock and soil analysis have been performed identifying an area of potential geothermal power development. With the geochemical analysis nearly completed, further testing (Magneto tellurics), will begin this month at approximately 100 locations to measure geophysical characteristics over the Area of Interest (AOI).  Based on the ...
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Geothermal Energy

Geothermal Potential of American Samoa

Note from ASREC: The following article was researched and written by Mr. Charles Visser, Principal Geoscientist at the National Renewable Energy Laboratory (NREL) in Golden, Colorado.  From this document, finalized in October, 2011, the American Samoa Government (ASG), has devised and initiated a three-phase plan to further investigate the territory’s geothermal potential.  Phase One of that investigation was completed this month, with findings to be uploaded soon.  By Charles Visser  Summary Tutuila, the most populous island in American Samoa, has no active volcanism and no reported surface evidence of hydrothermal activity. However, evidence of very young (post-cultural) volcanic activity on ...
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American Samoa Airborne LiDAR

As part of the American Samoa Geothermal investigation, Phase One, this LiDAR (Light Detection and Ranging) footage was taken earlier in the year to creating a three dimensional analysis of stratigraphic units in targeted resource areas ...
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