The panic that gripped residents of the southern parts of the Kingdom didn’t exactly come as a surprise to seismic experts when an earthquake with a magnitude of 5.1 on the Richter scale hit southeast Sibya in Jazan recently.
The 65 observatories of the National Center for Earthquakes and Volcanoes have been registering weak tremors that can only be recorded by its equipment.
The most quake-prone areas are between Madinah and the border village of Haql, and the aligning coastal lines, because of the existence of rifts like the Red Sea Rift, the Dead Sea Rift, and the Gulf of Aqaba.
Most earthquake activities are concentrated in Harat Al-Shaqah, north of Yanbu, which is described as the field of volcanic basalt belonging to the Holocene geological age.
Observatories monitored 30,000 tremors during 2007, and in May 2009, the observatories recorded significant volcanic activities by registering 950 tremors in three weeks, including the earthquake with a magnitude of 5.6 degrees on the Richter scale in Al-Eis town.
In 1995, an earthquake with a magnitude of 7.2 on the Richter scale occurred next to Haql town, followed by a series of aftershocks in Tabuk and Al-Bada’ center. Local sources said two people were killed in the earthquake and subsequent aftershocks. Aftershocks were estimated at 3,000 and continued for three months, and 90 of them were significant.
The area has had many earthquakes that led to the death of many people. An earthquake in Taima killed 20,000 people. More than 300 earthquakes hit the southern parts of the Kingdom from 1900 to 2006 with varying strengths of 3 and 6.6 degrees on the Richter scale.
Geologists say it’s hard to predict earthquakes, but there are some indications about seismic activity such as the rise or drop in ground-water levels, or the changing color of well waters. Sometimes low mist with sulfurous odor and strange animal behavior indicate earthquake activity.
Madinah and Haql areas found to be quake-prone
