Browsing Earth and Ocean Sciences by Title
Now showing items 17-34 of 34
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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. ... -
Quantitative geometric description of fracture systems in an andesite lava flow using terrestrial laser scanner data
(Elsevier, 2017-06-03)Permeability hosted in andesitic lava flows is dominantly controlled by fracture systems, with geometries that are often poorly constrained. This paper explores the fracture system geometry of an andesitic lava flow formed ... -
A review of the Rotokawa Geothermal Field, New Zealand
(Elsevier, 2015-07-29)The Rotokawa Geothermal Field of New Zealand has seen significant development over the last 20 years and has been the study site for new and innovative geological and geothermal research. This includes the one of the first ... -
Rock properties of Greywacke Basement hosting geothermal reservoirs, New Zealand: preliminary results
(Stanford University, 2014-02-24)Geothermal resources in New Zealand are known to be hosted in greywacke basement rocks. Fluid flow in these reservoirs and the wells that access them is controlled by fracture networks. As such it is of vital importance ... -
Statistical corrections of fracture sampling bias in boreholes from acoustic televiewer logs
(New Zealand Geothermal Workshop, 2012)Targeting structurally controlled permeability remains a challenge in high temperature geothermal fields, because of the difficulties in characterising faults and fractures and their behaviour within the reservoir. The ... -
Tectonic structure and permeability in the Taupô Rift: new insights from analysis of LiDAR derived dems
(New Zealand Geothermal Workshop, 2017-11-22)The location of permeable zones, and preliminary quantification of a geothermal well’s production or injection capacity are routinely interpreted from well pressure, temperature, and flow measurements made at ... -
Volcanic texture identification and influence on permeability using a borehole resistivity image log in the Whakamaru Group Ignimbrite, Wairakei Geothermal Field, New Zealand
(Workshop on Geothermal Reservoir Engineering, 2018-02-12)Discerning the contributions to fluid flow in a geothermal reservoir from intrinsic and structural permeability components is an important, yet difficult task. High-quality, resistivity borehole image log data (Formation ...