Calibration of the electric piezocone penetrometer for predicting sediment character and geologic mapping of Eocene Carolina coastal plain sediments.

摘要

The cone penetration test (CPT) is a cost effective, reliable technology for subsurface investigations in unconsolidated sediments. However, use of the technology for geologic mapping has been limited because of the lack of a reliable method to relate CPT measurements to quantifiable sediment characteristics. This study utilizes 562 sieve test results, acquired from twelve soil borings with adjacent CPT soundings, to develop a mathematical solution to relate CPT measurements to mud content (fines) for the Eocene Carolina Coastal Plain. The result is a method to directly translate CPT measurements into vertical fines content profiles, similar to down-hole geophysical logs, for geologic mapping application.; Effectiveness of the method for describing sediment character and mapping is demonstrated by comparing CPT fines content profiles to actual sediment characteristics in large scale exposures, as well as, core and natural gamma geophysical logs. This methodology is further extended to a regional scale by using CPT soundings to produce stratigraphic surface maps thus demonstrating the working application for geologic mapping with the CPT.