Deep Structure Of Long Valley, California, Based On Deep Reflections From Earthquakes

Zucca, J J; Kasameyer, P W

Title: Deep Structure Of Long Valley, California, Based On Deep Reflections From Earthquakes

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Abstract

Knowledge of the deep structure of Long Valley comes primarily from seismic studies. Most of these efforts have focused on delimiting the top of the inferred magma chamber. We present evidence for the location of the bottom of the low velocity layer (LVL). Two other studies have provided similar information. Steeples and Iyer (1976) inferred from teleseismic P-wave delays that low-velocity material extends from 7 km depth to 25 to 40 km, depending on the velocities assumed. Luetgert and Mooney (1985) have examined seismic refraction data from earthquake sources and have identified a reflection that appears to be from the lower boundary of a magma chamber. They detected the reflection with a linear array of single component stations, and assuming it traveled in a vertical plane, matched the travel time and apparent velocity (6.3 km/sec) to deduce that it was a P-P reflection from within a LVL. We recorded a similar phase with a 2-dimensional array of three-component stations, and carried out a similar analysis, but utilized additional information about the travel path, particle motions and amplitudes to constrain our interpretation. Our data comes from a passive seismic refraction experiment conducted during August 1982. Fourteen portable seismograph stations were deployedmore »« less

Authors:: Zucca, J J; Kasameyer, P W

Publication Date:: Thu Jan 01 00:00:00 EST 1987

Research Org.:: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 882028

Report Number(s):: UCRL-96369
TRN: US200618%%131

DOE Contract Number:: W-7405-ENG-48

Resource Type:: Journal Article

Country of Publication:: United States

Language:: English

Subject:: 58 GEOSCIENCES; CALIFORNIA; EARTHQUAKES; LONG VALLEY; MAGMA; REFLECTION; REFRACTION; SEISMOGRAPHS; GEOMORPHOLOGY; DEPTH; SEISMIC P WAVES

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                    Zucca, J J, and Kasameyer, P W. Deep Structure Of Long Valley, California, Based On Deep Reflections From Earthquakes.  United States: N. p., 1987. 
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                    Zucca, J J, & Kasameyer, P W. Deep Structure Of Long Valley, California, Based On Deep Reflections From Earthquakes.  United States.

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                    Zucca, J J, and Kasameyer, P W. 1987.  
        "Deep Structure Of Long Valley, California, Based On Deep Reflections From Earthquakes".  United States.  https://www.osti.gov/servlets/purl/882028.

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@article{osti_882028,

  title        = {Deep Structure Of Long Valley, California, Based On Deep Reflections From Earthquakes},

  author       = {Zucca, J J and Kasameyer, P W},

  abstractNote = {Knowledge of the deep structure of Long Valley comes primarily from seismic studies. Most of these efforts have focused on delimiting the top of the inferred magma chamber. We present evidence for the location of the bottom of the low velocity layer (LVL). Two other studies have provided similar information. Steeples and Iyer (1976) inferred from teleseismic P-wave delays that low-velocity material extends from 7 km depth to 25 to 40 km, depending on the velocities assumed. Luetgert and Mooney (1985) have examined seismic refraction data from earthquake sources and have identified a reflection that appears to be from the lower boundary of a magma chamber. They detected the reflection with a linear array of single component stations, and assuming it traveled in a vertical plane, matched the travel time and apparent velocity (6.3 km/sec) to deduce that it was a P-P reflection from within a LVL. We recorded a similar phase with a 2-dimensional array of three-component stations, and carried out a similar analysis, but utilized additional information about the travel path, particle motions and amplitudes to constrain our interpretation. Our data comes from a passive seismic refraction experiment conducted during August 1982. Fourteen portable seismograph stations were deployed in a network with approximately 5 km station spacing in the Mono Craters region north of Long Valley (Figure 1). The network recorded earthquakes located south of Long Valley and in the south moat. Three components of motion were recorded at all sites. The data represent one of the few times that three-component data has been collected for raypaths through a magma chamber in the Long Valley area.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/882028},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Thu Jan 01 00:00:00 EST 1987},

  month        = {Thu Jan 01 00:00:00 EST 1987}

}

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