Browsing Earth and Ocean Sciences by Title
Now showing items 9-28 of 34
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Electron backscatter diffraction (EBSD) in the SEM: applications to microstructures in minerals and rocks and recent technological advancements
(Sociedad Española de la Mineralogía, 2008-09-16)Electron backscatter diffraction (EBSD) is based on the principle that a beam of electrons generated in the scanning electron microscope (SEM) is the source of randomly scattered electrons in a specimen. The backscattered ... -
An energy-driven geologist
(The New Zealand Association of Scientists, 2013)[No abstract available] -
Exploring structure and stress from depth to surface in the Wairakei Geothermal Field, New Zealand
(International Geothermal Association, 2016-02-22)Structures such as fractures and faults have an important role as fluid flow pathways in geothermal fields, as the reservoir rocks hosting geothermal resources can often have little to no intrinsic permeability. As such, ... -
Fabrics produced mimetically during static metamorphism in retrogressed eclogites from the Zermatt-Saas zone, Western Italian Alps
(Elsevier, 2012-09-12)Lattice preferred orientations (LPOs) are commonly interpreted to form by dislocation creep. Consequently they are used to infer deformation at the metamorphic grade at which the minerals were stable, especially if those ... -
Feasibility of storing carbon dioxide on a tectonically active margin: New Zealand
(American Association of Petroleum Geologists, 2015-09-13)New Zealand's sedimentary basins was found to have available several gigatonnes of CO2 storage capacity. However, CO2 storage is currently untested in New Zealand. The country's position on an active Neogene plate boundary ... -
Fracture geometries and processes in andesites at Mt Ruapehu, New Zealand: implications for the fracture modelling of the Rotokawa Geothermal Field
(Le Consortium Gocad, 2014-09-16)Fluid flow in the high-temperature (300 C), andesite-hosted Rotokawa geothermal reservoir (Taupo Volcanic Zone (TVZ), New Zealand) is largely controlled by fractures and faults but their geometries are still poorly ... -
Fracture width and spacing distributions from borehole televiewer logs and cores in the Rotokawa Geothermal Field, New Zealand
(International Geothermal Association, 2015-04-19)The successful targeting of permeable fractures in geothermal fields is aided by understanding the spatial and geometric characteristics of fracture populations. Studies of numerous outcrop, and a limited number of geothermal ... -
Fractures interpreted from acoustic formation imaging technology: Correlation to permeability
(Stanford University, 2011-01-31)Permeable feed zones in geothermal wells are commonly identified using well profiles of temperature, pressure and fluid velocity measured at different injection rates during well completion testing and heat-up. While this ... -
Geothermal structural geology in New Zealand: Innovative characterisation and micro-analytical techniques
(International Geothermal Association, 2016-11-23)Many of New Zealand's geothermal reservoirs are hosted in rocks with low intrinsic permeability. As such, successful development of these resources relies on understanding the role subsurface structures, such as fractures ... -
Heterogeneity of structure and stress in the Rotokawa Geothermal Field, New Zealand
(American Geophysical Union (AGU), 2015-02-12)Geometric characterization of a geothermal reservoir's structures, and their relation to stress field orientation, is vital for resource development. Subsurface structure and stress field orientations of the Rotokawa ... -
Identifying the sources and sinks of CDOM/FDOM across the Mauritanian Shelf and their potential role in the decomposition of superoxide (O2- )
(Frontiers Media, 2016-08-03)Superoxide (O−2O2-) is a short lived reactive oxygen species (ROS) formed in seawater by photochemical or biological sources, it is important in the redox cycling of trace elements and organic matter in the ocean. The ... -
International ocean discovery program expedition 372 preliminary report: creeping gas hydrate slides and Hikurangi LWD, 26 November 2017 - 4 January 2018
(Texan A&M University, 2018-03)International Ocean Discovery Program (IODP) Expedition 372 combined two research topics, slow slip events (SSEs) on subduction faults (IODP Proposal 781A-Full) and actively deforming gas hydrate bearing landslides (IODP ... -
Interpretive review of the acoustic borehole image logs acquired to date in the Wairakei-Tauhara Geothermal Field
(Institute of Geological and Nuclear Sciences Limited, 2013)[No abstract available] -
Late-interseismic state of a continental plate-bounding fault: Petrophysical results from DFDP-1 wireline logging and core analysis, Alpine Fault, New Zealand
(American Geophysical Union (AGU), 2013)We present a geophysical characterization at 0.1-100 m scales of a major plate-bounding continental fault in a late-interseismic state. The Alpine Fault produces M-W approximate to 8 earthquakes every 200-400 years and ... -
Methods and techniques employed to monitor and manage carbon capture and sequestration (CCS) induced seismicity
(GNS Science, 2016)This report discusses the topic of induced seismicity resulting from the operations of subsurface CO2 injection at Carbon Capture and Storage (CCS) sites. The potential for induced seismicity to occur in CCS projects is ... -
Modelling fluid flow through fractured rock: Examples using TVZ geothermal reservoirs
(New Zealand Geothermal Workshop, 2015-11-18)Geothermal resources are often hosted within volcanic, plutonic, and basement-type lithologies. As such their matrix permeability can be very low and the transport and circulation of geothermal fluids will be dominated by ... -
The nature of fracture permeability in the basement greywacke at Kawerau Geothermal Field, New Zealand
(Stanford University, 2012-01-30)The Mesozoic basement at Kawerau Geothermal Field comprises well indurated, inter-bedded sandstones and argillites with a complex structural history. These rocks have very low matrix porosity but nonetheless host both ... -
New Zealand geothermal power plants as critical facilities: an active fault avoidance study in the Wairakei Geothermal Field, New Zealand
(International Geothermal Association, 2015-04-19)Active faults in rifts commonly provide high crustal permeability and control geothermal fluid pathways. However, active faults can also pose surface deformation hazards to geothermal power plants and associated infrastructure. ... -
Processing and analysis of high temperature geothermal acoustic borehole image logs in the Taupo Volcanic Zone, New Zealand
(Elsevier, 2014-06-19)Acoustic borehole televiewer (BHTV) logs provide direct observations of lithology, structure and in-situ stress in reservoirs, essential for successful well targeting and field management. Analyses of BHTV logs acquired ... -
Quantifying the stress distribution at the Rotokawa Geothermal Field, New Zealand
(New Zealand Geothermal Workshop, 2012)Knowledge of the orientation and magnitude of the principal stresses can be used to model the behavior of faults and fractures, and determine how they may influence fracture hosted permeability in geothermal reservoirs. ...