The term landslide refers to a rapid displacement of a mass of rock, residual soil, or sediments adjoining a slope, in which the center of gravity of the moving mass advances in a downward and outward direction. A similar movement proceeding at an imperceptible rate is called creep. The velocity of the masses involved in a typical landslide increases more or less rapidly from almost zero to at least 1 foot per hour. Then i t again decreases to a small value. By contrast, typical creep is a continuous movement which proceeds at an average rate of less than 1 foot per decade. Higher rates of creep movements are rather uncommon.
Figures & Tables
Application of Geology to Engineering Practice
Some years ago a group of geologists led by Professor C. R. Longwell of Yale University and Professor A. I . Levorsen of Stanford University proposed to honor Dr. Charles Peter Berkey, Newberry Professor Emeritus of Columbia University, for his life-long contributions in the field of engineering geology, by assembling and publishing a number of original papers each of which would deal with a special facet of the subject.
The Geological Society of America, through its President Dr. N. L. Bowen, appointed a committee to carry out this proposal and agreed to publish the symposium. Dr. W. O. Hotchkiss was duly appointed Chairman of a working group, among whom were Sidney Paige, W. S. Mead, J. P. Buwalda, and B. C. Moneymaker.
The authors, each selected for his particular knowledge in the field, have given generously of their time. I t was agreed that broad principles, rather than engineering or geologic detail, should be emphasized, but aside from this broad consideration each author was to prepare his material independently. To them all our thanks are due.
It is doubtful whether these papers need further introduction. Each is addressd to a technically trained audience and is planned to emphasize principles, rather than the minutiae of engineering and geologic practice. The title of the boor–The Application of Geology to Engineering Practice–is self-explanatory and is well understood by engineers and geologists.
- cohesionless materials
- engineering properties
- geologic hazards
- mass movements
- natural hazards
- potentiometric surface
- preventive measures
- rock mechanics
- shear stress
- slope stability
- soil mechanics