Physical processes and effects of magmatism in the Yucca Mountain region

Conference · Tue Dec 31 04:00:00 EST 1991

OSTI ID:138303

Valentine, G A; Crowe, B M ^[1]; Perry, F V ^[2]

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1. Los Alamos National Lab., NM (United States)
2. New Mexico Univ., Albuquerque, New Mexico (USA). Dept. of Geology

This paper describes initial studies related to the effects of volcanism on performance of the proposed Yucca Mountain radioactive waste repository, and to the general processes of magmatism in the Yucca Mountain region. Volcanism or igneous activity can affect the repository performance by ejection of waste onto the earth`s surface (eruptive effects), or by subsurface effects of hydrothermal processes and altered hydrology if an intrusion occurs within the repository block. Initial, conservative calculations of the volume of waste that might be erupted during a small-volume basaltic eruption (such as those which occurred in the Yucca Mountain region) indicate that regulatory limits might be exceeded. Current efforts to refine these calculations, based upon field studies at analog sites, are described. Studies of subsurface effects are just beginning, and are currently focused on field studies of intrusion properties and contact metamorphism at deeply eroded analog sites. General processes of magmatism are important for providing a physical basis for predictions of future volcanic activity. Initial studies have focused on modeling basaltic magma chambers in conjunction with petrographic and geochemical studies. An example of the thermal-fluid dynamic evolution of a small basaltic sill is described, based on numerical simulation. Quantification of eruption conditions can provide valuable information on the overall magmatic system. We are developing quantitative methods for mapping pyroclastic facies of small basaltic centers and, in combination with two-phase hydrodynamic simulation, using this information to estimate eruption conditions. Examples of such hydrodynamic simulations are presented, along with comparison to an historical eruption in Hawaii.

• Research Organization: Los Alamos National Lab., NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 138303
• Report Number(s): LA-UR--91-4041; CONF-920430--10; ON: DE92005056; IN: TWS-EES-5-12-91-01
• Country of Publication: United States
• Language: English

Related Subjects

05 NUCLEAR FUELS
54 ENVIRONMENTAL SCIENCES
DIKES
ENVIRONMENTAL IMPACTS
ERUPTION
FORECASTING
GEOLOGIC FRACTURES
GEOLOGIC STRATA
HYDROLOGY
HYDROTHERMAL SYSTEMS
MAGMA
MAGMATISM
MATHEMATICAL MODELS
MORPHOLOGY
PROBABILISTIC ESTIMATION
RADIOACTIVE WASTE DISPOSAL
RADIOACTIVE WASTES
RISK ASSESSMENT
TUFF
VOLCANIC REGIONS
VOLCANISM
YUCCA MOUNTAIN
Yucca Mountain Project