A 7.5 magnitude earthquake has rocked Iran’s southeastern province of Sistan and Baluchestan near the border with Pakistan.
Officials confirmed that up to 34 people had died due to the earthquake, while 80 were reported to be injured in the Mashkel area of Balochistan’s Washuk district alone, according to a report by Dispatch News Desk in Pakistan.
Several hundred houses were also reported to have collapsed, raising fears of further casualties in the area. Dozens of shops and buildings have also been destroyed by the tremors. According to the most recent reports, two Pakistan Army helicopters carrying medical teams and supplies have reached Mashkel, where personnel are now busy in relief and rescue efforts.
The tremor was powerful enough to be felt as far away as New Delhi, India, where it rocked tall buildings.
It was also felt in the Persian Gulf’s littoral states of Bahrain, Kuwait, Oman, Saudi Arabia and the United Arab Emirates.
The Iranian Seismological Center (IRSC) said the epicenter of the quake, which occurred at 15:14 local time at a depth of 18 kilometers on Tuesday, was situated 95 kilometers north of the city of Saravan.
The quake, unprecedented in the past 50 years, prompted officials to declare a state of emergency in the region.
Assessment and evaluation teams as well as rescue teams from the Iranian Red Crescent Society have been dispatched to the quake-stricken area, which is a sparsely populated rural area between the provincial cities of Saravan and Khash.
According to local officials, the Tuesday earthquake has caused no casualties in the quake-stricken areas. The Iranian Fars News Agency had earlier reported that 40 people had died as a result of the quake.
According to Iranian Press TV correspondent, several are feared dead and 100 others injured in Balochistan province of Pakistan near Iran border.
Officials and local sources told Press TV that several houses were destroyed due to earthquake in Panjgur District near Iran border on Tuesday.
A spokesman for the Russian contractor of the Bushehr nuclear power plant has said the quake did not affect the nuclear station.
The April 16, 2013 M 7.8 earthquake east of Khash, Iran, occurred as a result of normal faulting at an intermediate depth in the Arabian plate lithosphere, approximately 80 km beneath the Earth’s surface. Regional tectonics are dominated by the collisions of the Arabian and India plates with Eurasia; at the longitude of this event, the Arabian plate is converging towards the north-northeast at a rate of approximately 37 mm/yr with respect to the Eurasian plate. Arabian plate lithosphere is subducted beneath the Eurasian plate at the Makran coast of Pakistan and Iran, and becomes progressively deeper to the north.
The subducted Arabian plate is known to be seismically active to depths of about 160 km. The frequency of moderate and large earthquakes within the subducted Arabian plate is not high compared with similar events in some other subducted plates worldwide, but several earthquakes have occurred within this slab in the region of today’s event over the past 40 years, including a magnitude 6.7 shock 50 km to the south in 1983. In January of 2011, a M 7.2 earthquake occurred approximately 200 km to the east, in a similar tectonic environment to the April 16 earthquake.
Seismotectonics of the Middle East and Vicinity
No fewer than four major tectonic plates (Arabia, Eurasia, India, and Africa) and one smaller tectonic block (Anatolia) are responsible for seismicity and tectonics in the Middle East and surrounding region. Geologic development of the region is a consequence of a number of first-order plate tectonic processes that include subduction, large-scale transform faulting, compressional mountain building and crustal extension.
Mountain building in northern Pakistan and Afghanistan is the result of compressional tectonics associated with collision of the India plate moving northwards at a rate of 40 mm/yr with respect to the Eurasia plate. Continental thickening of the northern and western edge of the India subcontinent has produced the highest mountains in the world, including the Himalayan, Karakoram, Pamir and Hindu Kush ranges. Earthquake activity and faulting found in this region, as well as adjacent parts of Afghanistan and India, are due to collisional plate tectonics.
Beneath the Pamir-Hindu Kush Mountains of northern Afghanistan, earthquakes occur to depths as great as 200 km as a result of remnant lithospheric subduction. Shallower crustal earthquakes in the Pamir-Hindu Mountains occur primarily along the Main Pamir Thrust and other active Quaternary faults, which accommodate much of the region’s crustal shortening. The western and eastern margins of the Main Pamir Thrust display a combination of thrust and strike-slip mechanisms.
Along the western margin of the Tibetan Plateau, in the vicinity of southeastern Afghanistan and western Pakistan, the India plate translates obliquely relative to the Eurasia plate, resulting in a complex fold-and-thrust belt known as the Sulaiman Range. Faulting in this region includes strike-slip, reverse-slip and oblique-slip motion and often results in shallow, destructive earthquakes. The relatively fast moving left-lateral, strike-slip Chaman Fault system in southeastern Afghanistan accommodates translational motion between the India and Eurasia plates. In 1505, a segment of the Chaman Fault system near Kabul, Afghanistan ruptured causing widespread destruction of Kabul and surrounding villages. In the same region, the more recent 30 May 1935, M7.6 Quetta, Pakistan earthquake, occurred within the Sulaiman Range, killing between 30,000 and 60,000 people.
Off the south coast of Pakistan and southeast coast of Iran, the Makran trench is the present-day surface expression of active subduction of the Arabia plate beneath the continental Eurasia plate, which converge at a rate of approximately 20 mm/yr. Although the Makran subduction zone has a relatively slow convergence rate, it has produced large devastating earthquakes and tsunamis. For example, the November 27, 1945 M8.0 mega-thrust earthquake produced a tsunami within the Gulf of Oman and Arabia Sea, killing over 4,000 people. Northwest of this active subduction zone, collision of the Arabia and Eurasia plates forms the approximately 1,500-km-long fold and thrust belt of the Zagros Mountains, which crosses the whole of western Iran and extends into northeastern Iraq. Collision of the Arabia and Eurasia plates also causes crustal shortening in the Alborz Mountains and Kopet Dag in northern Iran. Eastern Iran experiences destructive earthquakes that originate on both strike-slip and reverse faults. For example, the 16 September 1978 M7.8 earthquake, along the southwest edge of the Dasht-e-Lut Basin killed at least 15,000 people.
Along the eastern margin of the Mediterranean region there is complex interaction between the Africa, Arabia and Eurasia plates. The Red Sea Rift is a spreading center between the Africa and Arabia plates, with a spreading rate of approximately 10mm/yr near its northern end, and 16mm/yr near its southern end (Chu, D. and Gordon, R. G., 1998). Seismicity rate and size of earthquakes has been relatively small along the spreading center, but the rifting process has produced a series of volcanic systems across western Saudi Arabia.
Further north, the Red Sea Rift terminates at the southern boundary of the Dead Sea Transform Fault. The Dead Sea Transform is a strike-slip fault that accommodates differential motion between the Africa and Arabia plates. Though both the Africa plate, to the west, and the Arabia plate, to the east, are moving in a NNE direction, the Arabia plate is moving slightly faster, resulting in the left-lateral, strike-slip motion along this segment of the plate boundary. Historically, earthquake activity along the Dead Sea Transform has been a significant hazard in the densely populated Levant region (eastern Mediterranean). For example, the November 1759 Near East earthquake is thought to have killed somewhere between 2,000-20,000 people. The northern termination of the Dead Sea Transform occurs within a complex tectonic region of southeast Turkey, where interaction of the Africa and Arabia plates and the Anatolia block occurs. This involves translational motion of the Anatolia Block westwards, with a speed of approximately 25mm/yr with respect to Eurasia, in order to accommodate closure of the Mediterranean basin.
The right-lateral, strike-slip North Anatolia Fault, in northern Turkey, accommodates much of the westwards motion between the Anatolia Block and Eurasia Plate. Between 1939 and 1999, a series of devastating M7.0+ strike-slip earthquakes propagated westwards along the North Anatolia Fault system. The westernmost of these earthquakes was the 17th August 1999, M7.6 Izmit earthquake, near the Sea of Marmara, killed approximately 17,000 people.
At the southern edge of the Anatolia Block lies the east-west trending Cyprian Arc with associated levels of moderate seismicity. The Cyprian Arc represents the convergent boundary between the Anatolia Block to the north and the Africa Plate to the south. The boundary is thought to join the East Anatolia Fault zone in eastern Turkey; however no certain geometry or sense of relative motion along the entire boundary is widely accepted.