ELECTRIC RESISTIVITY INVESTIGATION AT NUWEIBA HARBOUR GULF OF AQABA, SOUTH SINAI, EGYPT

ELECTRIC RESISTIVITY INVESTIGATION AT NUWEIBA
HARBOUR GULF OF AQABA, SOUTH SINAI, EGYPT
MAHMOUD ISMAIL ISMAIL MOHAMADEN
National Institute of Oceanography and Fisheries, Alexandria, Egypt.
Key wards: Resistivity, Vertical electric sounding (V.E.S.), cathodic.
ABSTRACT
The results obtained from the interpretation of the V.E.S.’s gave information regarding
the geological situation in the Nuweiba Harbour, Gulf of Aqaba south Sinai, Egypt. A total
of 20 vertical electrical soundings (V.E.S.’s) were conducted along 6 profiles. The
geoelectrical field emphasis some knowledge about structural geology and lithology of the
subsurface formations of the study area. In this work, the Schlumberger array with
maximum current electrode half spacing (AB/2) of 75 m was applied. This spacing is
sufficient to reach adequate depths for this study. The established geoelectric sections
reveal the presence of the following geoelectric units: (a) A superficial unit characterized
by electric resistivity value ranging from 2.47 to 106 ohm-m., and with a thickness ranges
from 0.7 to 9.7 m. (b) A second unit with electric resistivity values (0.82 – 24 ohm-m.) and
of depths from 0.35 to 5.8 m. (c) A third unit characterized by electric resistivity values
ranging from 0.7 and 6.5 ohm-m. This third unit has a maximum thickness of 22m. which
disappears at some localities. (d) A basal unit characterized by lower electric resistivity
values that ranging from 0.2 to 0.6 ohm-m.
Location for cathodic protection necessary for construction of civil engineering harbour
project is determined by the lowest values of resistivity values.