EarthScope

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• EarthScope
• Plate Boundary Observatory

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Introduction
EarthScope Revealing Earth's Secrets Jayme B.
Margolin PBO Siting Education and Outreach
Specialist margolin_at_unavco.org UNAVCO, Boulder,
Colorado February 25, 2008 Mesa Union School
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Outline

• The Plate Tectonic Theory
• Global Positioning System (GPS)
• Plate Boundary Observatory (PBO) and You
• Current Data and Science
• Geological Hazard Activity
• Conclusion

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Plate Tectonics
(from http//mediatheek.thinkquest.nl/, 2007)
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Plate Tectonics
The Theory of Plate Tectonics
(from http//en.wikipedia.org/wiki/Plate_tectonics
, 2008)
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Ring of Fire
(From www.worldbook.com, 2008)
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Plate Boundaries
Plate Tectonics

• Transform
• Divergent
• Convergent

(from USGS, 2005)
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Plate Movement
(from USGS, 2006)
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Global Positioning System (GPS) Examples
GPS Examples
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Method of Operation

• Global positioning system (GPS)
• Receiver determines location, speed, direction,
  and time
• 3 satellite signals are necessary to locate the
  receiver in 3D space
• 4th satellite is used for time accuracy
• Position calculated within sub-centimeter

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Anatomy of a GPS Station

• GPS antenna inside of dome, solidly attached into
  the ground with braces. If the ground moves, the
  station moves.
• Solar panel for power
• Equipment enclosure
• GPS receiver
• Power/batteries
• Communications/ radio/ modem
• Data storage/ memory

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Movement of GPS stations
GPS station positions change as plates move.
How will the position of these stations change
relative to one another?
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EarthScope Partners
EarthScope is funded by the National Science
Foundation and conducted in partnership with the
US Geological Survey.
EarthScope is being constructed, operated, and
maintained as a collaborative effort with UNAVCO,
IRIS, and Stanford University, with contributions
from NASA and several other national and
international organizations.
The data collected by EarthScopes three
observatories will help us to understand
processes that control earthquakes and volcanoes.
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SAFOD
A borehole laboratory on the San Andreas fault
studying the physics of earthquake nucleation at
the depths where earthquakes begin.
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US Array
A continent-spanning deployment of seismometers
for imaging the deep interior of the North
American continent
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Transportable Array
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Plate Boundary Observatory

• A continent-scale network of GPS, borehole, and
  laser strainmeters focusing on the extended plate
  boundary and extending into the continental
  interior
• Measurements of
• Extension/compression
• Dilatation
• Tilt

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PBO Instruments
1100 Continuous GPS
103 Borehole Strainmeters and Seismometers
5 Laser Strainmeters
28 Shallow Borehole Tiltmeters
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GPS Monuments
GPS Station
Monument drilling
Moderate impact Deep Drill Braced
GPS Monument
Monument installation
Final site
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PBO Science Goals

• Earthquake processes and seismic hazards
• Magmatic processes and volcanic hazards
• Active deformation and tectonics
• Exploration and discovery

Requires an Interdisciplinary Approach
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Faults - Chaos
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Mesa Union Region
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Visible Results
Deformed rocks within the San Andreas Fault zone
(from J.K. Nakata, 1988)
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So. CA GPS Sites
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Mesa Union School
Local GPS Stations
Site Webpage http//pboweb.unavco.org/shared/scrip
ts/stations/?checkkeyP729
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Time Series
(from Southern California Earthquake Center, 2007)
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Vectors
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Science Example

• Producing PBO GPS
• velocity solution maps
• Supported scientist Thorsten W. Becker
  (University of Southern California in Los
  Angeles)
• Main research interests as a geophysicist
  focuses on tectonic deformation

(from http//geodynamics.usc.edu/becker, 2007)
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Science in Use
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Hazards
Hazards
In addition to seismic hazards (earthquakes) in
your region, what are some other hazards?
Tsunamis
Liquefaction
Now lets have some fun
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Summary
Determine Through Geodetic (crustal movement)
Observations of Plate Boundaries
(from mymapman.com, 2008)
(from www.scenta.co.uk, 2007)
(from noaa, 2007)
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Science
Earth Science ... from the
descriptive to the numerical
from regional to
global
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Questions?

• Thank You

Are there any questions, comments, or concerns?
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Useful Web Links

• www.earthscope.org
• www.unavco.org
• www.unavco.org/EO
• pboweb.unavco.org/
• www.dlese.org/library/index.jsp
• projects.crustal.ucsb.edu/understanding/
• www.DaretoPrepare.org
• www.explorers.org/
• www.nsf.gov/home/grants
• sopac.ucsd.edu/

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Extra Slides
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Educators
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Data for Educators
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Science Examples
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PBO Network Overview

• Focused, dense deployments of GPS and strain
• 775 continuous Global Positioning Systems
• 175 borehole strainmeters
• 5 long baseline strain components
• Backbone network of GPS stations
• 100 sites to provide a long-wavelength,
  long-period synoptic view of the entire plate
  boundary zone. Receiver spacing is approximately
  200 km
• 16 backbone sites in eastern US at 400 km
  spacing
• Portable GPS receivers
• Pool of 100 portable GPS receivers for temporary
  deployments to areas not sufficiently covered by
  continuous GPS