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The Qayen earthquake, also known as the Ardekul or Qaen earthquake, struck northern Iran's Khorasan Province in the vicinity of Qaen on May 10, 1997 at 07:57 UTC (12:57 local time). The largest in the area since 1990, the earthquake registered 7.3 on the moment magnitude scale and was centered approximately 270 kilometers (170 mi) south of Mashhad on the village of Ardekul. The third earthquake that year to cause severe damage, it devastated the Birjand–Qayen region, killing 1,567 and injuring more than 2,300. The earthquake—which left 50,000 homeless and damaged or destroyed over 15,000 homes—was described as the deadliest of 1997 by the United States Geological Survey. Some 155 aftershocks caused further destruction and drove away survivors. The earthquake was later discovered to have been caused by a rupture along a fault that runs underneath the Iran–Afghanistan border.
Damage was eventually estimated at $100 million, and many countries responded to the emergency with donations of blankets, tents, clothing, and food. Rescue teams were also dispatched to assist local volunteers in finding survivors trapped under the debris. The destruction around the earthquake's epicenter was, in places, almost total; this has been attributed to poor construction practices in rural areas, and imparted momentum to a growing movement for changes in building codes for earthquake-safe buildings. With 1 in 3,000 deaths in Iran attributable to earthquakes, a US geophysicist has suggested that a country-wide rebuilding program would be needed to address the ongoing public safety concerns. (Full article...)
There have probably been many such eruptions during Earth's history beyond those shown in these lists. However erosion and plate tectonics have taken their toll, and many eruptions have not left enough evidence for geologists to establish their size. Even for the eruptions listed here, estimates of the volume erupted can be subject to considerable uncertainty. (Full article...)
The 2005 Qeshm earthquake occurred on November 27 at 13:52 IRST (10:22 UTC) on the sparsely populated Qeshm Island off Southern Iran, killing 13 people and devastating 13 villages. It was Iran's second major earthquake of 2005, following the one at Zarand in February. The epicenter was about 1,500 kilometers (930 mi) south of Tehran, close to Iran's southern borders. Initial measurements showed that the earthquake registered about 6.0 on the moment magnitude scale, although that was reduced to 5.8 after further analysis. More than 400 minor aftershocks followed the main quake, 36 of which were greater than magnitude 2.5. The earthquake occurred in a remote area during the middle of the day, limiting the number of fatalities. Iranian relief efforts were effective and largely adequate, leading the country to decline offers of support from other nations and UNICEF.
Qeshm Island is part of the Simply Folded Belt, the most seismically active part of the Zagros fold and thrust belt. Similar to most earthquakes in the area, the 2005 event resulted from reverse slip faulting. Since it lies in such a seismically active area, there is a high risk of destructive earthquakes in Iran; 1 in 3,000 deaths are attributable to earthquakes. One geophysicist has cited the lack of strict building codes as a serious concern. (Full article...)
An ice core is a core sample that is typically removed from an ice sheet or a high mountain glacier. Since the ice forms from the incremental buildup of annual layers of snow, lower layers are older than upper ones, and an ice core contains ice formed over a range of years. Cores are drilled with hand augers (for shallow holes) or powered drills; they can reach depths of over two miles (3.2 km), and contain ice up to 800,000 years old.
The physical properties of the ice and of material trapped in it can be used to reconstruct the climate over the age range of the core. The proportions of different oxygen and hydrogen isotopes provide information about ancient temperatures, and the air trapped in tiny bubbles can be analysed to determine the level of atmospheric gases such as carbon dioxide. Since heat flow in a large ice sheet is very slow, the borehole temperature is another indicator of temperature in the past. These data can be combined to find the climate model that best fits all the available data. (Full article...)
Between 3 and 4 million years ago, volcanic-derived mud flows called lahars streamed down several major mountains that included nearby but now extinct Mount Yana and Mount Maidu to become the Tuscan Formation. Basaltic and later andesitic to dacitic flows of lava covered increasingly larger areas of this formation to eventually form the lava plateau upon which the park is situated. About 600,000 years ago, Mount Tehama started to rise as a stratovolcano in the southwestern corner of the park, eventually reaching an estimated 11,000 ft (3,400 m) in height. (Full article...)
Mauna Loa has probably been erupting for at least 700,000 years, and may have emerged above sea level about 400,000 years ago. The oldest-known dated rocks are not older than 200,000 years. The volcano's magma comes from the Hawaii hotspot, which has been responsible for the creation of the Hawaiian island chain over tens of millions of years. The slow drift of the Pacific Plate will eventually carry Mauna Loa away from the hotspot within 500,000 to one million years from now, at which point it will become extinct. (Full article...)
The ACFEL ice auger showing an ice core pushed up into the core remover barrel.
Ice drilling allows scientists studying glaciers and ice sheets to gain access to what is beneath the ice, to take measurements along the interior of the ice, and to retrieve samples. Instruments can be placed in the drilled holes to record temperature, pressure, speed, direction of movement, and for other scientific research, such as neutrino detection. (Full article...)
Alfred Philippson (1 January 1864 – 28 March 1953) was a German geologist and geographer.
He was born at Bonn, son of Ludwig Philippson. He received his education at the gymnasium and university of his native town and at the University of Leipzig (Ph.D. 1886). In 1892 he became Privatdozent at Bonn, was appointed assistant professor seven years later, and in 1904 he was called to Bern as professor of geography. Having made voyages through Italy (Apulia region), Greece, Turkey, and Asia Minor, he published: Studien über Wasserscheiden, Berlin, 1886; Der Peloponnes, ib. 1892; Europa (with Neumann), Leipzig, 1894; Thessalien und Epirus, Berlin, 1897; Beiträge zur Kenntnis der Griechischen Inselwelt, Gotha, 1901; Das Mittelmeergebiet, Leipzig, 1904. He also published essays in the technical journals, such as Das fernste Italien. Geographische Reiseskizzen und Studien, Leipzig, 1925, and Apulien, Netherlands, 1937.
Since 1887 Philippson undertook, on a commission from the Berlin Akademie der Wissenschaften, an annual journey to Asia Minor for the purpose of geological investigation. His chief object in these excursions was to study, on a geological basis, the phenomena of the earth's surface both in their interrelationship and in their influence on the human race. (Full article...)
The Mariana Trench or Marianas Trench is located in the western Pacific Ocean about 200 kilometres (124 mi) east of the Mariana Islands; it is the deepestoceanic trench on Earth. It is crescent-shaped and measures about 2,550 km (1,580 mi) in length and 69 km (43 mi) in width. The maximum known depth is 10,984 ± 25 metres (36,037 ± 82 ft; 6.825 ± 0.016 mi) at the southern end of a small slot-shaped valley in its floor known as the Challenger Deep. If Mount Everest were hypothetically placed into the trench at this point, its peak would still be underwater by more than 2 kilometres (1.2 mi). (Full article...)
This false-color mosaic showing compositional variations in the geology of the Moon was constructed from a series of 53 images taken through three spectral filters by the imaging system of the Galileo spacecraft. Bright pinkish areas are highlands materials, such as those surrounding the oval lava-filled Mare Crisiumimpact basin toward the bottom. Blue to orange shades indicate volcanic lava flows. To the left of Crisium, the dark blue Mare Tranquillitatis is richer in titanium than the green and orange maria above it. Thin mineral-rich soils associated with relatively recent impacts are represented by light blue colors. The monochrome band on the right edge shows the unretouched surface of the moon.
This picture is a self-portrait of Curiosity on Mars at the "Big Sky" drilling site, where it collected a rock sample at the foothills of Aeolis Mons (Mount Sharp) in October 2015. The photograph combines dozens of images taken by the Mars Hand Lens Imager (MAHLI) camera at the end of the rover's robotic arm; the arm itself is not included, although its shadow is visible on the ground. Wrist motions and turret rotations on the arm allowed MAHLI to acquire the mosaic's component images.