A 4.4-magnitude earthquake was registered on Friday by the Egyptian National Seismic Network (ENSN).
It was a medium-intensity earthquake centered in the Mediterranean Sea north of the Egyptian coasts in an area called the Nile continental margin.
Dr. Ahmed Ali Badawi, Head of Seismology Department at the National Institute of Astronomical and Geophysical Research, said that the earthquake was registered at 4:19 am (Cairo local time).
Ali Badawi added: “The earthquake took place 230 kilometers north to Helwan, 92 kilometers from Rashid and 130 kilometers from Alexandria.”
He pointed out that the earthquake was felt by some residents of Cairo, explaining that in the event of aftershocks will be less than 3 degrees on the Richter Scale.
Noteworthy, Californians woke up to a 5.4-magnitude aftershock early Friday, renewing concerns one day after two decades of Southern California's greatest earthquake.
Susan Hough, a seismologist with the United States Geological Survey, said the 4:07 a.m. tremor, nine miles northeast of the Mojave Desert city of Ridgecrest near where Thursday’s earthquake took place, would likely be the strongest aftershock, although more powerful ones could follow. There have been about 200 aftershocks since the 6.4-magnitude earthquake on Thursday morning, which led to about two dozen fire and emergency medical calls but no serious injuries.
Thursday’s earthquake punctured a period of relative seismic calm in California, but scientists said it did not change their calculations of when the Big One might strike.
Although the faults around Ridgecrest are part of the larger San Andreas system that runs from the Gulf of California to Mendocino, north of San Francisco, Thursday’s earthquake did not relieve the stress on the San Andreas, said Paul Caruso, a geophysicist with the U.S.G.S. in Golden, Colo.
“We are not changing our forecast for the San Andreas,” Dr. Caruso said. “We still believe there’s a 70 percent chance of a magnitude 7 or greater in Southern California before 2030.”
The San Andreas fault, which runs near heavily populated areas and defines the boundary between the North American and Pacific tectonic plates, is considered the biggest seismic threat to California. Related cracks in the earth, like the Hayward fault that runs through Oakland and Berkeley in the San Francisco Bay Area, are also considered major threats.