JEDDAH, 2 October - An earthquake measuring 3.5 on the Richter scale hit the Red Sea at 6.58 p.m. on Saturday, according to a report of the National Earthquake Observation Center, a subsidiary of the Astronomical and Geophysical Research Center at the King Abdul Aziz City for Science and Technology. The epicenter of the tremor was off the coast of Al-Shaqiq. Dr. Abdul Aziz Radin, professor of Geology at the King Abdul Aziz University in Jeddah, said the university is working on an earthquake guide to the Red Sea area, Al-Madinah newspaper reported yesterday.