RECOGNITION FEATURES of TRANSLATIONAL BLOCK SLIDES

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Part 11

• RECOGNITIONFEATURES ofTRANSLATIONAL BLOCK
  SLIDES

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Topographic Expression of Translational Block
Slides

• Extended ridges or topographic knobs
• Convergent drainage
• Sharp downslope turns in contour lines

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Topographic Patterns on Composite Landslides

• Use drainage and topographic keys to recognize
  anomalous site characteristics typical of
  landslides
• Extended ridges or isolated knobs
• Sudden turns in hillside contours
• Convergent drainage

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Crowleys Ridge Translational Block Slides
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Translational landslides are usually fairly large
and involve underlying bedrock strata
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TRANSLATIONAL BLOCK SLIDES
Translational slides tend to detach along
pre-existing geologic discontinuities The
geologic structure generally mimics the regional
trends, making many of the older slides difficult
to recognize
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Dormant deep-seated bedrock slides are often
characterized by Y-shaped tributaries, anomalous
benches, and arcuate headscarp evacuation scars