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Allison, M. Lee

Publications and source records attributed to Allison, M. Lee.

4 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

State Geological Survey Contributions to the National Geothermal Data System (Final Technical Report)

The State Geological Survey Contributions to the National Geothermal Data System project is built on the work of the project managed by Boise State University to design and build the National Geothermal Data System, by deploying it nationwide and populating it with data principally from State Geological Surveys through collaboration with the Association of American State Geologists (AASG). This project subsequently incorporated the results of the design-build and other DOE-funded projects in support of the NGDS. The NGDS (www.geothermaldata.org) provides free open access to millions of data records, images, maps, and reports, sharing relevant geoscience, production, and land use data in 30+ categories to propel geothermal development and production in the U.S. NGDS currently serves information gathered from hundreds of the U.S. Department of Energy sponsored development and research projects and geologic data feeds from 60+ data providers throughout all 50 states. These data are relevant to geothermal energy exploration and development, but also have broad applicability in other areas including natural resources (e.g., energy, minerals, water), natural hazards, and land use and management.

15 GEOTHERMAL ENERGY↗
NASA NTRS1987

Ice-covered water volcanism on Ganymede

Eruption of liquid H2O magmas along extensional fractures and graben-bounding normal faults may have played a critical role in the development of Ganymede's grooved terrain. The resurfacing potential of a water magma is dependent on a variety of factors, including the areal extent of the source region, the rate of discharge, the thickness of the flow, and the time that it takes the flow to completely freeze to its base. In this paper the thermal evolution of such a flow is considered in detail. The minimum unfrozen lifetime of a 5-m flow is approximately 12.5 days while a 10-m flow would survive for at least 50 days. Heating resulting from frictional head loss could reasonably extend these lifetimes by 50 percent or more. With a discharge rate of the order of 1-10 cu km/d, an individual volcanic water flow could flood an area of about 10,000 sq km before freezing. As the flow solidifies, its volume will increase, thus lifting and arching its protective ice cover. Extensional fractures may then develop in the ice subparallel to the graben walls. These fractures could result in grooves directly, given a sufficiently thick (1 km) flow, or they may simply act to concentrate various tectonic forces that could initiate groove-producing faults.

Allison, M. Lee↗