Abstract: Halfaya oilfield is located in the plain of Mesopotamian, south Iraq. The subsurface soils mainly consist of silt, clay and sand. Soil property identification is an important aspect of the geotechnical engineering. It is required that the geotechnical investigation work be performed in accordance with the western codes and there are fairly great difference between the state of the practice in China and western countries. These differences exist in the definitions of silt and elastic silt, empirical relationship between soil properties and blow counts of Standard Penetration Test as well as the criteria for the relative density of the sandy soils. This paper compares the differences of the above aspects and provides recommendations of the geotechnical investigation work if the western code is being used.

Key words: Silt, Elastic Silt, Standard Penetration Tests, Energy Corrected Blow Counts, Relative Density of Sand