Amarillo by Morning: Data Visualization in Geostatistics

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Amarillo by Morning Data Visualization in
Geostatistics

• William V. Harper, Otterbein College, USA
  wharper_at_otterbein.edu
• Isobel Clark, Geostokos, Scotland
• Environmental Statistics, Session 6A2
• ICOTS8, Ljubljana, Slovenia
• 11 16 July 2010

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Amarillo by Morning a Haunting Country Song

• Amarillo by morning, up from San Antone.
• Everything that Ive got is just what Ive got
  on.
• When that sun is high in that Texas sky
• Ill be bucking it to county fair.
• Amarillo by morning, Amarillo Ill be there.
• They took my saddle in Houston, broke my leg in
  Santa Fe.
• Lost my wife and a girlfriend somewhere along the
  way.
• Well Ill be looking for eight when they pull
  that gate,
• And Im hoping that judge aint blind.
• Amarillo by morning, Amarillos on my mind.

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Amarillo, Wolfcamp Aquifer, and Nuclear Waste
Repository

• In the United States in 1987, the possible
  nuclear waste sites were reduced to
• Salt bed in Texas
• Basalt formation in Washington state
• Tuff formation near Las Vegas, Nevada
• Wolfcamp Aquifer underlies salt site
• Briny (salty) slow moving water
• Modeled as 2-D plane using geostatistics

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Geostatistics

• Geostatistics
• Spatial statistics used for continuous data
• Each data value has a location in space
• Roots in Mining, not Statistics
• Observations close have similar values
• Goals of Geostatistics
• Estimate spatial correlation structure
• Predict values at un-sampled locations

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Wolfcamp Potentiometric Data 85 values
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Wolfcamp Initial Assessment

• Higher values in Southwest, Lower in Northeast
• Travel path from Deaf Smith county toward
  Amarillo in lower Potter County
• If a breach, flow is toward Amarillo

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Kriging, Universal Kriging

• Universal Kriging (combines trend, kriging)
• Many possible iterative steps to produce minimum
  variance linear unbiased estimates
• Distribution Analysis, Data Transformation
• Trend, Isotropy/Anisotropy analysis
• Semi-variogram modeling of spatial variability
• Cross-Validation to partially validate model
• Kriged expected value map at un-sampled locations
• Kriged standard error map

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Will you be my Neighbor?

• Nearest Neighbor Analysis

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Empirical Semi-variogram, Semi-variogram Cloud

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Directional Semi-variograms get color version
from Is

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Directional Shaded Plot Semi-variograms

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Directional Semi-variograms on Regression
Residuals