THE RELATIONSHIP BETWEEN GEOLOGICAL CONDITIONS, EROSION CAPACITY AND EROSION CONTROL

THE DIRECT RELATIONSHIP BETWEEN THE GEOLOGICAL ENVIRONMENT, TOPOGRAPHIC RELIEF AND THE POTENTIAL EROSION CHARACTERISTICS OF VARIOUS GEOLOGICAL ROCK TYPES ARE DIRECTLY APPARENT. EXPERIENCE IN THE SOUTHERN CALIFORNIA AREA WITH CUT AND FILL SLOPE CONSTRUCTION ON MANY DIVERSE TYPES OF GEOLOGICAL FORMATIONS CONSISTING OF IGNEOUS, METAMORPHIC AND SEDIMENTARY ROCK TYPES DURING THE PERIOD FROM 1945-1969 FULLY DEMONSTRATE THIS RELATIONSHIP. THE PRIMARY PURPOSE FOR PLANTING CUT AND FILL SLOPES IS FOR THE PROTECTION OF THE SURFACE OF THOSE SLOPES FROM EXCESSIVE EROSION DURING PERIODS OF HEAVY RAINFALL. THE WEATHERING CHARACTERISTICS OF THE ROCKS EXPOSED THROUGHOUT THIS AREA, MOST OF WHICH INCLUDE VARIOUS TYPES OF MINERAL CONSTITUENTS THAT ARE SENSITIVE TO WATER AND OF AN EXPANSIVE NATURE, FACILITATE THE DEEP WEATHERING AND FORMATION OF DEEP SOIL OPENINGS OF SMALL CRACKS WHICH LEADS TO DEEPER AND DEEPER EROSION PENETRATION OF WATER DURING THE RAINY SEASON AND FURTHER DEEPER AND DEEPER EROSION AND SLUMPING. A CLASSIFICATION OF ROCK TYPES AND WEATHERING AND EROSION CHARACTERISTICS ARE INCLUDED BASED UPON THE 20 YEARS EXPERIENCE IN THE SOUTHERN CALIFORNIA AREA. RELATIONSHIPS BETWEEN ROCK AND SOIL TYPES AND VEGETATIVE COVER REQUIRED ARE DISCUSSED IN TERMS OF FUTURE PERFORMANCE OF THE SLOPES INVOLVED AND EXPECTED MAINTENANCE BY INDIVIDUAL HOMEOWNERS. DEVELOPMENT OF ORDINANCES AND FIRE RESISTANT PLANT AND GROUND COVER FOR SLOPES AND THE EFFECTIVENESS OF THESE MEASURES ARE DISCUSSED. /AUTHOR/

Media Info

  • Serial:
    • Issue Number: 0

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Filing Info

  • Accession Number: 00229740
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Mar 9 1970 12:00AM