Geothermal and ground water exploration on Maui, Hawaii, by applying D.C. electrical soundings

illmapsTwenty-one Schlumberger resistivity soundings were performed on the island of Maui. Analysis consisted of one-dimensional modeling using an automatic ridge-regression inversion algorithm (Anderson, 1979). The inversion results were compared with available well-log information and geologic maps in order to make geologic interpretations. The soundings were conducted primarily to estimate the depth to and the electrical resistivity of, seawater-saturated basalt for different parts of the island. The resistivity of seawater-saturated basalt on Maui ranges between 3.5 and 60 ohm-meters. The lowest values occurred near Ukumehame canyon, on the south rift zone of West Maui. In this area, which is the site of a warm water (33°C) well, the computed resistivity for seawater-saturated basalt is about 4 ohm-m. Using typical Hawaiian basalt porosity values of 15% to 25%, Archie's Law implies temperatures of between 62° and 171°C at depths below 200 meters in the Ukumehame area. Freshwater piezometric heads were estimated from the sounding data. The largest freshwater head (91 m) was obtained in Keanae valley. The inferred large volume of freshwater is perched on Keanae alluvial valley fill and is observed in a well (W100) towards the back of the valley. All other freshwater heads are under 4 m, indicating that the freshwater lens is rather thin near the coast at the areas surveyed.U.S. Department of Energy"This research was supported by a Department of Energy grant, No. DE-AC03-80SF10819 as a phase of geothermal assessment of the State of Hawaii."M.S

Hawaii geothermal resource assessment program, direct heat resource assessment final report, February 1, 1979 to January 31, 1980

Bibliography: p. 53-54. Material contains illustrations and maps.During 1979 reconnaissance field surveys were conducted on the islands of Hawaii, Maui, and Oahu with the objective of confirming groundwater chemical data and geophysical data compiled during the preliminary regional assessment of Phase I of the Direct Heat Resource Assessment Program. The exploration techniques applied include (1) groundwater chemistry, (2) mercury-radon surveys, (3) isotopic composition of groundwaters, (4) time domain electromagnetics, and (5) Schlumberger resistivity surveys. The results of these surveys can be classified as follows: (1) Hawaii: Kailua-Kona, strong geochemical anomalies; Kawaihae, strong geophysical anomalies, moderate to strong geochemical anomalies; Hualalai northwest rift, weak geochemical and moderate geophysical anomalies; South Point, moderate to weak geophysical anomalies; Hualalai southeast rift, weak geophysical anomalies; Keaau, weak geophysical and geochemical anomalies; (2) Maui: Haiku-Paia, strong geochemical anomalies; Olowalu-Ukamehame canyons, moderate to strong geochemical and geophysical anomalies; Lahaina, weak geochemical and geophysical anomlies; (3) Oahu: Lualualei, moderate to strong geochemical and geophysical anomlies; Waimanalo-Maunawili, insufficient data.Work performed under contract DE-AS03-ET792702

Seismic studies on Kilauea Volcano, Hawaii Island

This volume contains reports on seismological studies done in conjunction with other geophysical and geochemical studies of the Hawaii Geothermal Project. The studies were conducted on the easternmost portion of the East Rift Zone of Kilauea Volcano, near the eventual site of the initial well, HGP-A, drilled by the Hawaii Geothermal Project. The microearthquake survey by Suyenaga and Furumoto found, among other patterns of seismicity, a small cluster of events at 1-to 3-km depth in the immediate vicinity of HGP-A. Another microearthquake survey conducted by Mattice and Furumoto over a high electrical conductivity anomaly located west of HGP-A found it to be probably more seismically active than the area around the well site. Norris and Furumoto contoured noise levels but found no local amplification at any frequency associated with the geothermal reservoir. However, noise may be associated with magmatic activity. The crustal structure of the area was studied with two sets of seismic refraction profiles reported by Suyenaga and by Broyles. The surface layer has a low but highly variable velocity (0.8 to 1.6 km/sec) and consists of interlayered aa and pahoehoe flows with large voids. A jump in velocity to 2.5 to 3.0 km/sec occurs near sea level and is attributed to saturation of water. A layer of velocity about 5.0 km/sec lies between the 3.0-km/sec and a 7.0-km/sec layer. The latter is interpreted as the dike complex and locally is found as shallow as 2 to 2.5 km. Furumoto combines microearthquake, source mechanism, gravity and thermal data into an interpretation of the process of geothermal reservoir formation in the East Rift Zone.Prepared for NATIONAL SCIENCE FOUNDATION, Grant GI-38319 and ENERGY RESEARCH AND DEVELOPMENT AGENCY, Grant E(04-3)-1093

Preliminary geothermal assessment surveys for the State of Hawaii

Transactions, Geothermal Resources Council, Volume 4"The Geothermal Resource Assessment Program of the Hawaii Institute of Geophysics has conducted a series of geochemical and geophysical surveys in ten separate locations within the State of Hawaii in an effort to identify and assess potential geothermal areas throughout the state. The techniques applied include groundwater chemistry and temperatures, soil mercury surveys, ground radon emanometry, time-domain electromagnetic surveys and Schlumberger resistivity soundings. Although geochemical and geophysical anomalies were identified in nearly all the survey sites, those areas which show most promise, based on presently available data, for a geothermal resource are as follows: Puna, Kailua Kona, and Kawaihae on the island of Hawaii; Haiku-Paia and Olowalu-Ukumehame canyons on Maui; and Lualualei Valley on Oahu. Further surveys are planned for most of these areas in order to further define the nature of the thermal resource present.

Hawaii Geothermal Resource Assessment Program, direct heat resource assessment interim report, February 1, 1979 to January 31, 1980

During 1979 reconnaissance field surveys were conducted on the islands of Hawaii, Maui, and Oahu with the objective of confirming groundwater chemical data and geophysical data compiled during the preliminary regional assessment of Phase I of the Direct Heat Resource Assessment Program. The exploration techniques applied include (1) groundwater chemistry, (2) mercury-radon surveys, (3) isotopic composition of groundwaters, (4) time domain electromagnetics, and (5) Schlumberger resistivity surveys. The results of these surveys can be classified as follows: (1) Hawaii: Kailua-Kona, strong geochemical anomalies; Kawaihae, strong geophysical anomalies, moderate to strong geochemical anomalies; Hualalai northwest rift, weak geochemical and moderate geophysical anomalies; South Point, moderate to weak geophysical anomalies; Hualalai southeast rift, weak geophysical anomalies; Keaau, weak geophysical and geochemical anomalies; (2) Maui: Haiku-Paia, strong geochemical anomalies; Olowalu-Ukamehame canyons, moderate to strong geochemical and geophysical anomalies; Lahaina, weak geochemical and geophysical anomalies; (3) Oahu: Lualualei, moderate to strong geochemical and geophysical anomalies; Waimanalo-Maunawili, insufficient data.Work performed under Contract DE-AS03-ET7927023

Investigation of geothermal potential in the Waianae caldera area, Western Oahu, Hawaii

"Studies of Lualualei Valley, Oahu have been conducted to determine whether a thermal anomaly exists in the area and, if so, to identify sites at which subsurface techniques should be utilized to characterize the resource. Geologic mapping identifies several caldera and rift zone structures in the Valley and provides a tentative outline of their boundaries. Clay mineralogy studies indicate that minor geothermal alteration of near-surface rocks has occurred at some period in the history of the area. Schlumberger resistivity soundings indicate the presence of a low resistivity layer beneath the valley floor, which has been tentatively attributed to warm water-saturated basalt. Soil and groundwater chemistry studies outline several geochemical anomalies around the perimeter and within the inferred caldera boundaries. The observed anomalies strongly suggest a subsurface heat source. Recommendations for further exploratory work to confirm the presence of a geothermal reservoir include more intensive ·surveys in a few selected areas of the valley as well as the drilling of at least three shallow (1000-m) holes for subsurface geochemical, geological and geophysical studies.""Prepared for Western States Cooperative Direct Heat Resource Assessment."Contents: Geology of Oahu and Waianae Volcano / Malcolm E. Cox and Donald M. Thomas -- Detailed geological mapping / John M. Sinton -- Mineral assemblages of basalt and soil samples / Donald M. Helstern and Pow-foong Fan -- Summary of regional geophysics / Malcolm E. Cox -- Geoelectric surveys / Mark D. Mattice and James P. Kauahikaua -- Geochemical surveys / Malcolm E. Cox and Donald M. ThomasBibliography: pages 73-76.U.S. Department of Energy grant no. DOE/ID/01713-

Three dimensional picture of the local structure of 1,4-Polybutadiene from a complete atomistic model and neutron scattering data

An efficient method of combining neutron diffraction data over an extended Q range with detailed atomistic models is presented. A quantitative and qualitative mapping of the organization of the chain conformation in both glass and liquid phase has been performed. The proposed structural refinement method is based on the exploitation of the intrachain features of the diffraction pattern by the use of internal coordinates for bond lengths, valence angles and torsion rotations. Models are built stochastically by assignment of these internal coordinates from probability distributions with limited variable parameters. Variation of these parameters is used in the construction of models that minimize the differences between the observed and calculated structure factors. A series of neutron scattering data of 1,4-polybutadiene at the region 20320 K is presented. Analysis of the experimental data yield bond lengths for C-C and C=C of 1.54 and 1.35 Å respectively. Valence angles of the backbone were found to be at 112 and 122.8 for the CCC and CC=C respectively. Three torsion angles corresponding to the double bond and the adjacent R and β bonds were found to occupy cis and trans, s(, trans and g( and trans states, respectively. We compare our results with theoretical predictions, computer simulations, RIS models, and previously reported experimental results