On the basis of data obtained from boring and surface survey to Quaternary sediments in the district under consideration, has it become clear that thickness of the alluvium is less than 15m. and early to middle Pleistocene formations lie under the Alluvium.
Besides standard penetration test to these sediments indicates that N value of Alluvial fine to medium sand and silt is not more than 10 at shallower than 5m. underground, while that of Diluvial sand is more than 25 at deeper than 15m. But as for gravel, their N value is not always in proportion to depth where they 1ie.
The Alluvium is composed mostly of shallow sea sediments, on the other hand, the Diluvium contains very often tuffs, and lacustrine materials in the lower part and bay ones in the upper.