An earthquake measuring 4.0 on the Richter scale jolted the island of El Hierro Wednesday morning, which is the strongest earthquake that has yet been felt in the region. The quake, which occurred at 08:54 a.m. local time, took place at a depth of just 20 meters under the earth\'s crust off the north coast of the most westerly of the Spanish controlled Canary Islands. There have been over 40 tremors recorded in recent hours off the coast of the island with the majority occurring off the north coast, while Sunday had registered over 70 tremors, of which the strongest measured 3.9 on the Richter scale. Over 10,700 tremors have been registered since the first tremor was registered on July 17. Meanwhile the underwater volcano which re-entered into eruption off the south of the island continues to expel magma from its crater and deepen the color of the stain in the ocean as a result of the eruption. Although the local government in Canary Island has not yet taken steps to evacuate residents, as it did during the first eruption, which began on October 10, the Spanish military has stepped up preparations of a second evacuation. The Military Emergency Unit (UME) has transported a tent village with the capacity to house up to 2,000 people in response to a petition from the regional government.