Shear source multiazimuth near- and far-offset vertical seismic profiles, Asal Rift, Republic of Djibouti

Hirn, A; Magnier, S A

doi:10.1029/92JB00222

Title: Shear source multiazimuth near- and far-offset vertical seismic profiles, Asal Rift, Republic of Djibouti

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Abstract

A three-component borehole seismic data set obtained in the Asal rift zone shows that azimuthal anisotropy may be present with the fast propagation direction aligned with the present-day rift axis. This is seen on the near- and far-offset vertical seismic profile (VSP) data from the two source points lying parallel to the rift axis. The third orthogonal source point gives propagation times characteristic of near-horizontal paths along the detected slow direction. The reflected VSP wave field contains both P and S energy. The main P and S reflections correlate well and correspond to thin clay and siltstone layers interspersed within the lava flow series. Some evidence exists for a change with depth of the amount or direction of the anisotropy found in the uppermost 400 m.

Authors:

Hirn, A; Magnier, S A ^[1]

Institut de Physique du Globe, Paris (France)

Publication Date:: Thu Dec 10 00:00:00 EST 1992

OSTI Identifier:: 7093287

Resource Type:: Journal Article

Journal Name:: Journal of Geophysical Research; (United States)

Additional Journal Information:: Journal Volume: 97:B13; Journal ID: ISSN 0148-0227

Country of Publication:: United States

Language:: English

Subject:: 15 GEOTHERMAL ENERGY; GEOTHERMAL FIELDS; SEISMIC SURVEYS; ANISOTROPY; BOREHOLES; CLAYS; GEOTHERMAL EXPLORATION; LAVA; SEISMIC P WAVES; SEISMIC S WAVES; SEISMOLOGY; SILTSTONES; CAVITIES; EXPLORATION; GEOPHYSICAL SURVEYS; ROCKS; SEDIMENTARY ROCKS; SEISMIC WAVES; SURVEYS; 150300* - Geothermal Exploration & Exploration Technology

Citation Formats


                    Hirn, A, and Magnier, S A. Shear source multiazimuth near- and far-offset vertical seismic profiles, Asal Rift, Republic of Djibouti.  United States: N. p., 1992. 
        Web.  doi:10.1029/92JB00222.

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                    Hirn, A, & Magnier, S A. Shear source multiazimuth near- and far-offset vertical seismic profiles, Asal Rift, Republic of Djibouti.  United States.  https://doi.org/10.1029/92JB00222

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                    Hirn, A, and Magnier, S A. 1992.  
        "Shear source multiazimuth near- and far-offset vertical seismic profiles, Asal Rift, Republic of Djibouti".  United States.  https://doi.org/10.1029/92JB00222.

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@article{osti_7093287,

  title        = {Shear source multiazimuth near- and far-offset vertical seismic profiles, Asal Rift, Republic of Djibouti},

  author       = {Hirn, A and Magnier, S A},

  abstractNote = {A three-component borehole seismic data set obtained in the Asal rift zone shows that azimuthal anisotropy may be present with the fast propagation direction aligned with the present-day rift axis. This is seen on the near- and far-offset vertical seismic profile (VSP) data from the two source points lying parallel to the rift axis. The third orthogonal source point gives propagation times characteristic of near-horizontal paths along the detected slow direction. The reflected VSP wave field contains both P and S energy. The main P and S reflections correlate well and correspond to thin clay and siltstone layers interspersed within the lava flow series. Some evidence exists for a change with depth of the amount or direction of the anisotropy found in the uppermost 400 m.},

  doi          = {10.1029/92JB00222},

  url          = {https://www.osti.gov/biblio/7093287},
  journal      = {Journal of Geophysical Research; (United States)},

  issn         = {0148-0227},

  number       = ,

  volume       = 97:B13,

  place        = {United States},

  year         = {Thu Dec 10 00:00:00 EST 1992},

  month        = {Thu Dec 10 00:00:00 EST 1992}

}

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