Geophysics

1
Geophysics

• Jesse Yoburn
• UTEP Presentation 4/14/03
• Advisors Dr. Ramon Arrowsmith Dr. Matt Fouch

2
Data used thus far

• Seismic Anisotropy
• Heat
• Heat Flow
• Heat Production
• Thermal Conductivity
• Aeromagnetics

3
Seismic Anisotropy

• Shear wave splitting measurements of seismic
  anisotropy
• Taken from tabular data
• Seismic Anisotropy Beneath the Continents
  Probing the Depths of Geology
• Silver, PG, Annual Rev. Earth Planet Sci., 24,
  385-432, 1996.
• Others
• Split into two individual shapefiles
• Splitting Time
• Fast Polarization Direction
• Fast direction is (roughly) the direction of flow
  in the mantle and/or direction of maximum
  extension.

4
(No Transcript)
5
Interactive

• Able to click on a data point, determine exact
  Lat, Long, Splitting Time, Direction, Error, etc.
• Hyperlink to reference

6
Heat Flow, Production, and Conductivity

• Data taken from
• A New Global Heat Flow Compilation
• Assembled by Henry N. Pollack, Suzanne J. Hurter,
  and Jeffrey R. Johnson Department of Geological
  Sciences at the University of Michigan Ann Arbor.
  March, 1991
• North America Data cropped from database,
  assembled into a new file

7
Heat Flow Background

• Calculated using Fouriers Law
• q  K (?t/?z) K thermal conductivity
• Measures energy transfer (flux) through the
  (near) surface
• Uses
• Local Imaging magma chambers
• Global Lithospheric thickness
• Averages (mW/m2)
• Oceanic 101 Continental 65 Global 80

8
Heat Flow
(mW/m2)
9
Heat Production

• Typical range 0-8 microwatts/m3
• Related to radioactive decay, mantle plumes, etc.

10
Heat Production
(10-6 W/m3)
11
Thermal Conductivity

• Determined through boreholes (some points overlap
  with heat flow)
• Shows the efficiency of heat transfer
• Used to determine heat flow (K of Fouriers Law)

12
Thermal Conductivity
(W/mK)
13
Aeromagnetics

• Data taken from online USGS Open-File Reports
• United States Magnetic Compilation Project
• AZ http//pubs.usgs.gov/of/2001/ofr-01-0081/html/
  arizona.htm
• NM http//pubs.usgs.gov/of/2001/ofr-01-0061/html/
  newmex.htm

14
Aeromagnetics
(nT)
15
Future Work

• New Datasets
• Geodetic Velocity Fields
• Crust Mantle xenoliths
• PACE Results
• Crustal thickness (non-PACE)
• Seismic Lines
• Upper Mantle Discontinuity Structure
• Regional Tomography
• GIS related
• Hyperlink all references (web, PDF)
• Topography? (For reference, identification of
  regional features)