Browsing Earth and Ocean Sciences (Conference Papers) by Title
Now showing items 1-18 of 18
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Comparing borehole televiewer logs with continuous core: An example from New Zealand
(International Geothermal Association, 2015-04-19)The use of borehole televiewer logging is a recent addition to the well logging toolkit available to the geothermal industry in New Zealand. The information acquired from borehole televiewer (BHTV) equipment, such as the ... -
A damage mechanics approach to modeling failure in Greywacke rock
(New Zealand Geothermal Workshop, 2014)Fracture networks within greywacke basement rocks often control fluid flow in geothermal reservoirs in New Zealand. Thermal, hydrological, chemical, and mechanical processes affect the evolution of these fracture networks. ... -
Discussion between a reservoir engineer and a geologist: permeability identification from completion test data and borehole image logs integration
(39th 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 different ... -
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 ... -
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, ... -
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 ... -
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. ... -
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. ... -
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 ...