Saturday 30 March 2013

Twenty-eight miners reported dead after explosion at Chinese coal mine.

Twenty-eight miners are reported to have died in a gas explosion at the Babao Coal Mine in Jilin Province, in the far northeast of China, at 10.40 pm local time (1.40 pm GMT) on Friday 29 March 2013. A further 13 workers suffered miner injuries; rescuers are not looking for any further people.

The location of the Babao Coal Mine. Google Maps.

Gas explosions in coal mines are an unpleasantly common event. Coal is formed by the compression and heating of plant matter in deeply buried sediments. The remaining coal is mostly carbon, with other elements that  were present in the original material being squeezed out by the pressure. However if these are not able to escape they will be trapped as pockets of gas, typically a mix of methane, hydrogen, carbon monoxide, water vapor and volatile hydrocarbons.

China gains 70% of its energy from coal-burning power stations, which places the country under great pressure to maintain coal supplies. This has led to a poor safety record within the mining sector, particularly in the private sector, where there is a culture of seeking quick profits in poorly regulated (and often officially non-existent) mines. State owned mines are often thought to be better regulated, but still compare badly to mines in other parts of the world; the Babao Coal Mine is run by the state-owned Tonghua Mining Group.

See also 83 feared dead after Tibetan landslipPolish miners rescued after EarthquakeSeven workers killed by mine explosion in Hunan Province, ChinaMiners trapped by flooding at Qielichong Coal Mine in Hunan Province, China and At least 21 miners killed in mining disaster in Yunnan Province, China.

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Earthquake of the coast of El Hierro.

On Friday 29 March 2013, slightly after 5.00 pm GMT, the United States Geological Survey recorded a Magnitude 4.6 Earthquake at a depth of 17.3 km, roughly 30 km southwest of El Hierro in the Canary Islands. This is a moderately large Earthquake, but is unlikely to have been felt this far offshore.


The location of the 29 March 2013 Earthquake. Google Maps.

The Canary Islands are a group of volcanic islands fueled by a mantle plume rising through the African Plate, on which they are situated. The plume is rising from deep within the Earth, and is independent of the movement of the tectonic plates at the Earth's surface. As the plate moves relative to the hotspot new volcanic islands form on its surface, each over the hotspot when it forms, with the oldest islands of the chain in the east (the African Plate is being pushed east by the expansion of the Atlantic Ocean, but the hotspot is relatively motionless). Earthquake activity to the south of El Hierro began in July 2011, since when there has been considerably activity including a number of volcanic eruptions. In December 2011 it was confirmed that a new volcanic fissure had opened up beneath the sea to the south of El Hierro, and a new volcanic island is apparently in the process of being born.

See also Fresh volcanic activity on El HierroOngoing volcanic activity on El Hierro in the Canary Islands, Tourists evacuated due to volcanic activity on El Hierro in the Canary Islands and Volcanoes and Earthquakes on Sciency Thoughts YouTube.

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Fireball over Wyoming.

A fireball was seen traveling from southwest to northeast over Wyoming at about 5.45 am local time (11.45 GMT) on Thursday 28 March 2013, according to the American Meteor Society, who also received witness statements from Colorado, South Dakota, Montana and Alberta. The fireball was observed to flare green and blue, suggesting the object which caused it was composed largely of nickel and magnesium.

Map showing the location of witness reports for the 28 March fireball. Mike Hankey/American Meteor Society.

A fireball is defined as a meteor (shooting star) brighter than the planet Venus. These are typically caused by pieces of rock burning up in the atmosphere, but can be the result of manmade space-junk burning up on re-entry.

Witness reports can help astronomers to understand these events. If you witnessed this fireball you can report it to the American Meteor Society here.


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Homes evacuated after Arkansas oil leak.

A number of homes in Mayflower, Arkansas, were evacuated after pipeline carrying crude oil developed a leak at about 3.00 pm local time (about 8.00 pm GMT) on Friday 29 March 2013. The oil flowed across gardens and residential streets as well as entering a stream and drainage ditches running under Highway 365 and Interstate 40. The Arkansas Department of Emergency Management have been building earth dams to prevent the oil from entering nearby Lake Conway. The pipeline, which is owned by Exxon Mobil and carries crude oil from Canada to Texas, has been shut down.

Oil running down a residential street and across gardens in Mayflower, Arkansas, on Friday 29 March 2013. Fox 16.

The cause of the link has yet to be determined; the pipeline was buried and no excavation work was being carried out at the time when the rupture occurred. The pipeline crosses several waterways in the area and could potentially present a threat to water supplies if it developed a leak in the wrong place. The incident is being investigated by Exxon Mobil.

The location of the 29 March pipeline leak. Google Maps.


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Earthquake in Staffordshire.

On Thursday 28 March 2013, at 8.25 pm GMT, the British Geological Survey recorded a Magnitude 1.6 Earthquake at a depth of 7 km, roughly 5 km south of Stafford. This is to small to have caused any serious damage or casualties, but is large enough that it may have been felt locally.

The location of the 28 March Earthquake. Google Maps.

The precise cause of Earthquakes in the UK can be hard to determine, and most are probably the result of more than one source of tectonic stress. The country is being pushed to the east by the expansion of the Atlantic Ocean and to the north by the impact of Africa into Europe from the south. It is also affected by lesser spreading centers beneath the North Sea, Rhine Valley and Bay of Biscay. Finally there is glacial rebound; much of the north of the UK was covered by a thick layer of glacial ice until about 10 000 years ago, pushing the rocks of the British lithosphere down into the underlying mantle. This ice is now gone and the rocks of the lithosphere are still rebounding (slowly) into there original position, causing the occasional Earthquake in the process.

Witness reports can help geologists to understand Earthquake events, and the structures that cause them. If you felt this quake, or were in the area but did not (which is also useful information) then you can report it to the British Geological Survey here.


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Friday 29 March 2013

83 feared dead after Tibetan landslip.

83 mineworkers are feared to have died after a major landslide hit a mining settlement in Tibet at about 6.00 am local time on Friday 29 March 2013 (roughly 10.00 pm on Thursday 28 March, GMT). The landslip occurred in Maizhokunggar County, about 68 km from the Tibetan capitol of Lhasa, when an area of slope 3 km long collapsed causing around 2 million cubic meters of mud and rock to overrun part of the  Jiama Copper Gold Polymetallic Mine, which produces gold, silver, copper and molybdenum.

Operations at the Jiama Mine before the landslip. Claude Arpi.

The site is located at 4600 m, making operations there difficult at the best of times. It is essentially a mountaintop-removal type mine, covering an area of 144 km². Whilst it is a mine, and therefore has a considerable amount of excavation equipment, but a lot of this has also been buried. Over a thousand rescue workers are said to be present at the site, including firefighters, medical teams, police and sniffer dog teams.

The Chinese mine industry has a poor environmental and safety record, though there have been attempts to reform this in the past few years. The Jiama Mine has had a checkered history, with complains about environmental degradation and poor safety from the local population. It was taken over by the Tibet Huatailong Mining Development Co., a subsidiary of the China National Gold Group Corporation, in 2009, when it was promised that improvements would be made to the mine's operation.


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Magnitude 4.1 Earthquake in Montenegro.

On Thursday 28 March 2013, slightly before 5.15 pm local time (slightly before 4.15 pm GMT) the United States Geological Survey recorded a Magnitude 4.1 Earthquake at a depth of 9.1 km, roughly 3 km north of the coastal resort of Budvar. This small enough that serious damage or casualties are unlikely, but large enough to have been felt over a large area.

The location of the 28 March 2013 Earthquake. Google Maps.

The coastal region of Montenegro, and the other states of the western Balkan Peninsula, forms the eastern margin of the Adriatic Plate, a piece of the African Plate that has broken away and is now wedged into the southern part of the Eurasian Plate. This is being squeezed by the impact of Africa into Europe from the south, which is pushing western Italy, which sits on the Eurasian Plate, to the east, and Greece and Turkey, which sit on the Aegean and Anatolian Plates, to the west. This squeezing leads to uplift around the margins of the Adriatic Plate, in the Apennine Mountains of central Italy and the mountain ranges of the west Balkan Peninsula.


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Thursday 28 March 2013

Man swallowed by sinkhole in Shenzhen, South China.

A man was killed in Shenzhen City in Guangdong Province on Wednesday 27 March 2013, when a huge sinkhole opened up in a pavement in a residential area, swallowing him whole. Twenty-five-year-old security guard Yang Jiabin was swallowed instantly when the hole, described as eight meters wide and sixteen meters deep, opened up beneath him. He was pulled from the hole by rescuers, but died later in hospital.

Sinkhole in Shenzhen City which opened up on 27 March 2013. Guardian.

Sinkholes are generally caused by water eroding soft limestone or unconsolidated deposits from beneath, causing a hole that works its way upwards and eventually opening spectacularly at the surface. This particular one appears to have been formed when drainage pipes beneath the surface burst and washed away deposits. The area has been suffering heavy rainfall, which may have caused the pipes to overload, or they may have been damaged by work on a construction site adjacent to the affected pavement. Local authorities have launched an investigation.


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Major landslip on Whidbey Island, Washington State.

A major landslip occurred on Whidbey Island, Washington State, at about 4.15 am local time (about 11.15 am GMT) on Wednesday 27 March 2013. Severely damaging one home and destroying a section of road that cut of twenty more. The twenty isolated homes and a further seventeen judged to be potentially unsafe by Central Whidbey Island Fire and Rescue were evacuated. No injuries have been reported, and only twelve people were reported to have been evacuated during the incident, as many properties in the area are holiday homes only inhabited seasonally.

House damaged by the 27 March landslip on Whidbey Island. Though apparently structurally sound this property has more-or-less totally lost its foundations, making it unlikely it can be saved. KING 5/Reuters.

Whidbey Island is notoriously prone to such erosional landslip events. Much of the island is made up of unconsolidated glacial deposits, held together with dried clay rather than lithified by mineral deposits. Such deposits can quickly become waterlogged following heavy rainfall (something Washington State is famed for) and lose all cohesion. The United States Geological Survey estimates that 51% of the coastline of Whidbey Island is at risk from such collapses.

Aerial photograph of part of the landslip on Whidbey Island. Associated Press.


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Wednesday 27 March 2013

Two new species of terrestrial Flatworm from Brazil.

Flatworms (Platyhelminths) are among the simplest animals, and generally considered to be one of the oldest animal groups; they have almost no fossil record, but this is unsurprising given their small size and lack of hard parts. Flatworms are bilaterally symmetrical, but lack a true body cavity, meaning that they have to be small enough for nutrients to diffuse through their tissues by osmosis.

In a paper published in the journal Zootaxa on 13 December 2013, a team of scientists led by Ana Maria Leal-Zanchet of the Instituto de Pesquisas de Planárias and Programa de Pós-Graduação em Biologia at the Universidade do Vale do Rio dos Sinos describe two new species of Flatworms form Brazil. Both species are placed in the genus Pasipha, which is made up of elongate worms from the Neotropical region.

The first new species is named Pasipha backesi, in honour of Albano Backes, an expert in the ecology of Araucaria (Monkey Puzzle) Forests. Pasipha backesi is a 30-50 mm dark brown Flatworm with yellow and black stripes and dorsal eyes. The species was found at São Francisco de Paula in Rio Grande do Sul State.

Pasipha backesi. Leal-Zanchet et al. (2012).

The second species described is Pasipha brevilineata, where brevilineata means thin stripes, referring to a long, thin stripe running the length of the worm's dorsal surface (back). It is a 25-55 mm dark brown or black Flatworm. This species was also discovered at São Francisco de Paula in Rio Grande do Sul State.

Pasipha brevilineataLeal-Zanchet et al. (2012).


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Nigeria threatens Shell with US$11.5 billion in fines and compensation payments over the Bonga Oil Spill.

The Nigerian National Oil Spill Detection and Response Agency and Nigerian Maritime Administration and Safety Agency have recommended that oil giant Shell be ordered to pay a total of US$11.5 billion over the Bonga Oil Spill, which resulted in around 40 000 barrels of oil being lost into the sea off the Nigerian coast in December 2011. This is an unprecedentedly large sum from the Nigerian agencies, which have often been accused of being to close to oil producers. Shell Nigeria has contested the amount and claims much of the oil damage was caused by a second leak from an unnamed third party vessel.

Satellite image showing the extent of the Bonga Oil Spill.  Skytruth.

The spill occurred in December 2011, when an offshore storage facility developed problems while transferring oil to a tanker. Shell estimated the loss to be slightly under 40 000 barrels, though independent agencies suggested the spill might have been three times as large. The spill was treated with dispersants, which the oil company claim prevented the oil from reaching the shore. 

However around a hundred communities in the Niger Delta region were affected by oil washing onshore during the incident, something for which Shell denies responsibility, citing a second spill from an unnamed vessel. Given the disparity between the amount of oil Shell admit to having lost and the amount independent agencies estimate was in the water, this would suggest the unnamed vessel lost around twice as much as the Shell facility, which given Shell admits to having lost the equivalent of 20% of one day's production for the entire oil-field, seems slightly improbable. 

As a result of this the Nigerian National Oil Spill Detection and Response Agency has recommended to a hearing of the Nigerian Parliament that Shell be fined US$5 billion for environmental damages and The Nigerian Maritime Administration and Safety Agency has suggested that the company pay a further $6.5 billion in compensation to communities in the affected area. It is unclear if Nigeria has the legal framework to enforce these charges, though potentially they could be pursued through the courts in other nations, particularly The Netherlands where Shell Nigeria's parent company, Shell Oil, is based.


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At least one person dead following Magnitude 6.0 Earthquake in Taiwan.

Central Taiwan was struck by a Magnitude 6.0 Earthquake at a depth of 20.7 km, slightly after 10.00 am local time (slightly after 2.00 am GMT) on Wednesday 27 March 2013, according to the United States Geological Survey. This is a fairly severe quake, and is reported to have caused a temple wall to collapse  in Nantou County in the central part of the island, killing a 71-year-old woman. Nineteen other people are known to have been injured, and a number of buildings damaged by the quake, which was felt across the island and shook buildings in the capitol, Taipei.

Damage to the facade of a building in Taichung Municipality, central Taiwan. Reuters.

Taiwan has a complex tectonic setting, lying on the boundary between the Eurasian and Philippine Plates, with the Eurasian Plate being subducted beneath the Philippine Plate in the South and the Philippine Plate being subducted beneath the Eurasian in the East. Subduction is not a smooth process even in simple settings, with plates typically sticking together as pressure from tectonic expansion elsewhere builds up, then suddenly breaking apart and shifting abruptly, causing Earthquakes. The more complex situation in Taiwan makes the country extremely Earthquake-prone, though it is well prepared for such events, often weathering quakes that would cause devastation elsewhere without serious problems. Occasional large events do still cause severe problems for Taiwan, however; a magnitude 7.6 quake killed over 2300 people there in 1999, leading the country to erect a museum as a memorial.

The tectonic setting beneath Taiwan. Caltech.


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Magnitude 6.2 Earthquake beneath Guatemala.

On Monday 25 March 2013, slightly after 5.00 pm local time (slightly after 11.00 pm GMT), the United States Geological Survey recorded a Magnitude 6.2 Earthquake 200 km beneath Guatemala, close to the capitol, Guatemala City. This is a major Earthquake, and would be very dangerous close to the surface, but is not particularly dangerous at this depth since the pressure waves of the Earthquake lose energy as they pass through solid rock. The quake is likely to have been felt over a wide area of the country, as well as in neighboring states Mexico, Belize, Honduras and El Salvador.

Map showing the area over which the 25 March Earthquake was likely to have been felt. USGS.

Guatemala lies on the southern tip of the North American Plate, close to it's boundary with the Caribean Plate, which underlies most of Central America. To the south and west the Cocos Plate, which underlies part of the east Pacific, is being subducted beneath along the Middle American Trench, which follows the coast of Central America at a distance of about 100 km. The Cocos Plate passes under the North American and Caribbean Plates as it is subducted, and this quake almost certainly occurred on the margin of these two plates. Subduction is not a smooth process; the two plates constantly stick together and break apart as the pressure builds up, causing the occasional Earthquake in the process. 

Map showing the tectonic plates beneath Central America. John Elliot/University of Oxford.


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Tuesday 26 March 2013

Exxon Mobil fined $1.7 million for Yellowstone River oil spill.

The US Department of Transportation's Pipeline and Hazardous Materials Safety Administration announced it was fining the oil company Exxon Mobil US$1.7 million for safety violations which led to 238 000 liters of oil entering the Yellowstone River in Montana in July 2011. The incident occurred during seasonal flooding, leading to scouring of the riverbed, exposing a pipeline buried a meter beneath the surface, and contributing towards its rupturing. The spill caused a plume of oil 40 km long, fouling riverbanks, causing residents to be evacuated and disrupting the tourist industry in Yellowstone National Park.

Oil on the Yellowstone River near Laurel, Montana. Associated Press.

The agency found that Exxon should have foreseen the possibility of scouring and erosion affecting the pipeline and taken appropriate precautions. Furthermore it took pipeline controllers in Houston almost an hour to shut down the pipeline after realizing there was a problem, significantly increasing the amount of oil entering the river. In total over 100 km of riverbank, killing fish and wildlife and leading to a cleanup operation that lasted several months and which cost Exxon an estimated US$135 million. 

The federal fine comes on top of $1.6 million the company has already agreed to pay the State of Montana for water pollution violations. Exxon will have 30 days to appeal the decision.


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Earthquake off the coast of Tunisia.

On Monday 25 March 2013, slighlty before 11.10 pm local time (slightly before 10.10 pm, GMT) the United States Geological Survey recoreded a Magnitude 4.1 Earthquake at a depth of 15.7 km, 67 km offshore from Monastir on the Tunisian coast. This is a moderately large Earthquake, but some way from land, so it is unlikely to have caused any damage or casualties, and may not have been felt by anyone.

The location of the 25 March Earthquake. USGS.

Tunisia is not a country generally associated with Earthquakes, but is close to an active tectonic margin, with the boundary between the African and Eurasian Plates running along the north coast of the country, then along the south coast of Sicilly. This is a convergent margin, with the two continental masses being pushed together by the northward movement of Africa. This is a convergent margin, with Africa being partially subducted beneath the Eaurasian Plate and fuelling the volcanoes of southern and western Italy, and compression and folding of the southern part of the Eurasian Plate, causing uplift in the Appenines and Alps.


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Woman dies as house destroyed by landslip in Looe, Cornwall.

A woman was reportedly killed when her house collapsed in a landslip in Looe, Cornwall, on Friday 22 March 2013. She has been named as Susan Norman, a 68-year-old grandmother who lived in one of three single-occupancy flats inside the property. The house collapsed slightly before 6.00 am, but it was not until 1.15 pm that the Cornwall Fire and Rescue Service determined the property was sufficiently structurally sound for searchers and rescue dogs to enter. A body was removed at about 6.00 pm. A further 15 people have been evacuated from neighboring properties, and several roads and a railway line in the area are closed to traffic.

Police and Fire Fighters at the scene of the house collapse on 22 March. James Dadzitis/SWNS.

The landslip occurred following heavy rainfall, which apparently weakened the rock under the house. Residents had apparently complained to Cornwall Council about blocked drains which were causing a build-up of standing water in the road, and which has been linked to smaller landslips in the area in January and December.


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Eruption on Mount Lokon, Sulawesi.

Mount Lokon on northern Sulawesi erupted explosively slightly before 8.00 am local time on Wednesday 20 March 2013 (slightly before midnight on 19 March, GMT), throwing a column of ask 2 km into the sky, according to Badan Nasional Penangulanggan Bencana (Indonesia's Disaster Mitigation Agency). The eruption came from the Tomohon crater, which lies on a sadle between the more prominent Lokon and Empung craters, and which has been erupting intermittently since 2011, though this eruption was described as exceptionally loud, shocking local people.

The ash column over Mount Lokon. Viva.

Mount Lokon is on Sulawesi's Northern Peninsula, which forms one end of the Sangihe Volcanic Arc, a string of volcanic islands which runs from Sulawesi to Mindanao Island in the Philippines. The arc is formed as part of the Molucca Plate to the east is subducted beneath the Sangihe Plate to the west. As the Molucca Plate sinks into the Earth, it is partially melted by friction and the heat of the Earth's interior. Some of the melted material then rises through the overlying plate, fueling the volcanoes of the Sangihe Arc.


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Monday 25 March 2013

A new species of Oil Bee from northeast Brazil.

Oil Bees (Centridini) are largish Bees with special combs of bristles or velvety pads on their legs and abdomens, which they use to gather floral oils instead of or as well as nectar and pollen. They are mostly found in the Neotropics.

In a paper published in the journal ZooKeys on 27 December 2012, Thiago Mahlmann and Favízia Freitas de Oliveira of the Laboratório de Bionomia, Biogeografia e Sistemática de Insetos at the Instituto de Biologia at the Universidade Federal da Bahia, describe a new species of Oil Bee from northeastern Brazil, described from museum specimens examined during in a review of the genus Centris. The species has been known since at least the mid-nineteen-eighties, but has not previously been described formally.

The new species is named Centris byrsonimae; a name which has been in use for the species since 1985, when it was used by Jesus Moure to describe specimens in collections, though he never detailed his criteria for including specimens within the species and died in 2010. It is a 10 mm brown Bee.

Centris byrsonimae; female (top) and male (bottom). Scale bars are 5 mm. Mahlman & Oliviera (2012).


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Earthquake beneath Loch Maree.

On Sunday 24 March 2013, slightly after 10.00 pm GMT, the British Geological Survey recorded a Magnitude 2.0 Earthquake 7 km beneath Loch Maree in the Scottish Highlands. This is a small quake unlikely to have caused any damage or casualties, and given its remote location may not have felt by anybody.

The location of the 24 March 2013 Earthquake. Google Maps.

The precise cause of Earthquakes can be hard to determine in the UK, a country which lacks a single obvious source of tectonic activity, and most quakes are the result of the interaction of more than one source of stress. The UK is being pushed to the east by the expansion of the Atlantic Ocean and to the north by the impact of Africa into Europe from the south. It is also affected by lesser centers of expansion beneath the North Sea, Rhine Valley and Bay of Biscay, all of which exert some stress upon rocks in the UK. Finally there is glacial rebound; until about 10 000 years ago much of the north of Britain was covered by a thick layer of glacial ice, which pushed the rocks of the lithosphere down into the underlying mantle. This ice is now gone, and the rocks are (slowly) springing back into place, causing the occasional Earthquake in the process. This is particularly true in western Scotland, where the Pleistocene ice is believed to have been at its thickest, and which is now the most Earthquake-prone part of the country.

Witness reports of Earthquakes can help scientists to understand these events and the processes that cause them. If you felt this quake (or if you were in the area but did not, which is also useful information) then you can report it to the British Geological Survey here.


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At least six killed by West Java landslide.

Six people are known to have been killed following a landslide in West Java according to the Badan Nasional Penangulanggan Bencana (Indonesia's Disaster Mitigation Agency), with another eleven still missing. Another two people have reportedly been seriously injured. The occured around 5.30 am on 25 March 2013 local time (10.30 pm on 24 March, GMT )in Cililin Subdistrict following heavy rains, destroying a number of houses in Mukapayung Village. Rescue efforts are being coordinated by the Badan Nasional Penangulanggan Bencana, with help from the Police, Indonesian Red Cross and local volunteers, who are sorting through debris by hand. There have been a number of other landslides in the area, some of which may also have led to casualties.

 Villagers in Makapayung after the 25 March 2013 landslide. Associated Press.

Indonesia is prone to flash floods during the monsoon season, and in recent years has suffered from a growing number of landlides, which has been linked to deforestation on mountainsides. Indonesia has a rapidly growing population, with 138 million people living on Java (which has an area of 128 000 km2, roughly the same as England or North Carolina) alone. This, combined with a rapid expansion in comercial farming for export crops, has lead to widespread deforestation, making slopes vulnerable to landslides, as soils become waterlogged without the extensive treecover to keep them in place. 

Presure for agricultural land has led to increasing use of steeper slopes. Indonesia Tourism.


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Sunday 24 March 2013

A new species of Lungfish from the Late Devonian of northwest Australia.

Lungfish are an ancient group of Vertebrates more closely related to the Tetrapods (terrestrial Vertebrates) than to other groups of Fish. They get their name from their ability to breath air, which is useful in anoxic or seasonal waters; all modern species are freshwater and most can no longer use their gills to extract oxygen from water, though ancient Lungfish are known to have originated in fully marine waters. The group have a fossil record dating back to at least the Devonian, and were one of the most numerous Fish groups in the Palaeozoic.

In a paper published in the journal Palaeontology on 9 January 2012, Alice Clement of the Research School of Earth Sciences at the Australian National University in Canberra describes a new species of Lungfish from the Late Devonian Gogo Formation of northern Western Australia.

The Gogo Formation is a Fossil Lagerstätte in the Kimberly Region of Western Australia. It is noted for its diverse fish fauna, which are preserved in limestone concretions, and recovered by slowly dissolving  the concretions in weak acid. The deposits were laid down in anoxic lagoons behind algal reefs in the Late Devonian.

The location and outcrop distribution of the Gogo Formation. Clement (2012).

The new species of Lungfish is described from a single specimen from a limestone concretion from the Long Wells Area. It is placed in the genus Rhinodipterus, which has previously only been known from Europe and Russia, and given the specific name kimberleyensis, meaning 'from Kimberly'.

The skull of Rhinodipterus kimberlyensis in dorsal (A & B) and lateral (C & D) views. B & D are interpretive drawings based upon A & C. Abbreviations: A, skull roof bone A; art.c.r, articulation surface for cranial ribs; art.mnd, articulation surface for mandible; B, skull roof bone B; f.a.orb, foramen for orbital artery; ft.hy, hyomandibular facet; gr.op, groove for ophthalmic superficialis nerve VII; gr.v.jug, groove for jugular vein; hy.sp, facet for hyosuspensory ligament; I, skull roof bone I; J, skull roof bone J; L, skull roof bone L; med.cav, median cavity; n.I, foramen for olfactory nerve I; n.II, foramen
for optic nerve II; n.X, foramen for vagus nerve X; olf, olfactory canals I; orb, position of orbit; p.o.sc, orbital sensory canal pores; p.l, pit line; pr.I, posterior projection of I bone; psph, parasphenoid; qu, quadrate; sc, scales; sp.occ, spino-occipital nerve foramen; t.p, tooth plate; X, skull roof bone X; Y1, skull roof bone Y1; Y2, skull roof bone Y2; Z, skull roof
bone Z. Arrow indicates midline. Clement (2012).

Rhinodipterus kimberlyensis appears to have been a long snouted fish, with limited dentition and oral a mouth that did not open to a very high angle. This implies that it was probably a suction feeder targeting soft-bodied prey. This is a common strategy among modern Fish, and is also the primary feeding method in Walruses.

The skull of Rhinodipterus kimberlyensis in ventral (A & B) anterior (C)  and anterioventral (D) views. B is an interpretive drawing based upon A. Abbreviations: art.c.r, articulation surface for cranial ribs; cr.dl, dorsolateral cristae; cr.m, median crista; crp, corpus of parasphenoid; dent, dentine; ec.cav, extracranial space; ext, anteromedial extension of pterygoid and prearticular tooth plates; ext, anteromedial extension of pterygoid and prearticular tooth plates; f.a.ic, foramen for internal carotid artery; f.a.occ, foramen for occipital artery; f.a.orb, foramen for orbital artery; f.a.ps, foramen for efferent pseudobranchial artery; gr.op, groove for ophthalmic superficialis nerve VII; gr.v.jug, groove for jugular vein; med.cav, median cavity;  n.X, foramen for vagus nerve X; olf, olfactory canals I; psph, parasphenoid; pt, pterygoid; stk, stalk of parasphenoid; t.p, tooth plate; t.r, tooth row. 


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Saturday 23 March 2013

The taxonomic implications of host preference in Large Blue Butterflies.

Butterflies of the genus Maculinea (Large Blues) are social parasites targeting Ants of the genus Myrmica. The Butterflies lay their eggs on Gentian Flowers (Gentiana spp.) where the caterpillars emerge and pass through a number of instars (growth phases separated by molting events), before reaching a final larval stage, which secretes chemicals attractive to the host Ants, which then cary them back to their nests and feed them as they would their own larvae. 

The life cycle of Large Blue Butterflies. (a) The adult female, living about 5 days, lays 50-100 white eggs on the leaves and flower buds of Gentiana spp. (b) The young caterpillar bores into the plant, where it feeds on the developing seeds for 10-15 days, reaching 2% of its adult biomass. (c) The caterpillar emerges and falls to the ground, where it secretes chemicals attractive to ants of the genus Myrmica, who carry the caterpillar back to their nest. (d) The caterpillar competes with the ant larvae in the nest. Each species is capable of secreting chemicals specific to one species of ant; if carried to the wrong sort of nest it stops secreting chemicals, relying on the general smell of the nest to provoke the ants to feed it, however this is much less reliable and frequently results in the death of the caterpillar. (e) The growing ant makes vocalizations similar to the ants' queen, causing it to be fed in preference to the ants' own larvae. It feeds this way for 10-22 months before emerging as an adult and repeating the life-cycle. Thomas et al. (2013).


The taxonomy of Large Blue Butterflies is notoriously hard to unravel. The genus is currently split into six morphospecies (species differentiated by their appearance) but it is thought likely that each of these is made up of a number of different cryptic species. In order to test this a team of scientists led by Jeremy Thomas of the Department of Zoology at the University of Oxford and the Centre for Ecology and Hydrology carried out an experiment in which Butterflies of the species Maculinea rebeli from Poland and Spain were raised under laboratory conditions, along with their respective hosts. The results of the study were published in a paper in the Proceedings of the Royal Society Series B on 22 January 2013.

Thomas et al. found that the Butterflies from Poland used Ants of the species Myrmica sabuleti, while those from Spain used Myrmica schencki. Neither group of Butterflies were capable of surviving with the host of the other, suggesting that they are reproductively isolated, and should be regarded as separate species. 

This has important conservation implications. All Large Blue Butterflies are considered to be threatened by habitat loss. If the known morphospecies are all made up of a number of different cryptic species, as seems likely, then the reproductive populations of each of these populations will be much lower than is currently thought, and the species will be at greater risk of extinction.


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Earthquake under the Lleyn Peninsula.

On Friday 22 March 2013, slightly before 1.00 pm, GMT, the British Geological Survey recorded a Magnitude 2.2 Earthquake at a depth of 12 km beneath the Lleyn Peninsula in North Wales, roughly 20 km west of Porthmadog. This is not a large Earthquake, and occuring at this depth in a fairly remote location, it is quite likely that this event was not witnessed by anyone, and it is highly unlikely to have caused any damage or injuries.

The location of the 22 March Earthquake. Google Maps.

Small Earthquakes are not uncommon in the UK, though more serious events are rare; there has only ever been one recorded Earthquake-related death in Wales, in 1940, when an elderly woman fell down a flight of stairs in Porthmadog.

The precise cause of Earthquakes in the UK can be hard to determine, with most probably being the result of the interplay of more than one source of tectonic stress. The UK is being pushed to the east by the expansion of the Atlantic Ocean (allong with the rest of Eurasia) and to the north by the impact of Africa into Europe from the south. It is also affected by lesser spreading centers beneath the North Sea, Rhine Valley and Bay of Bicay. Finally it is subject to glacial rebound; until about 10 000 years ago much of the north of the country was covered by a thick layer of glacial ice, pushing the rocks of the British lithosphere down into the underlying mantle. These rocks are now rebounding (slowly) into place, causing the occational Earthquake in the process. This is particularly true in the north and west of the country, with Earthquakes being most common on the west coast of Scotland.

Witness accounts can help geologists to understand Earthquakes and the geological processes that cause them. If you felt this quake, or if you were in the area but did not (which is also useful information) then you can report it to the British Geological Survey here.


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Fireball over the northeastern United States.

A fireball was seen streaking through the sky over the US Coast from South Carolina to Maine, and inland as far as Ohio and Ontario, on the evening of Friday 22 March. The object was described as outshining both the Moon and the lights of New York City, and was described as probably being a rock the size of a volleyball by Derek Pitts of the Franklin Institute.

Map showing siting reports for the 22 March fireball. Mike Hankey/American Meteor Society.

The object appears to have first become visible in the Ohio/east Pennsylvania region, moving to the east, before breaking up as it passed over New York and disappearing out to sea. Such events are relatively common, and are being noticed more in the press at the moment following the breakup of an exceptionally large object over the Russian city of Cherblinsk in February.


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Willard Bay State Park, Utah, closed by oil spill.

Willard Bay is a freshwater reservior seperated off from Great Salt Lake in 1964. It suplies freshwater to much of northern Utah, an is a popular recreational facility, with camping, boating and fishing facilities. On Monday 18 March 2013 the northern part of the park was closed following a leak from a deisel pipeline connecting Salt Lake City to Burley, Idaho, which was detected when opperators Chevron detected a fall in pressue in the pipe.

Map showing the location of Willard Bay State Park. Standard-Examiner.

Two campers and the family of the park manager were evacuated and the northern part of the park, where the spill occurred, was closed as a precaution. Since the southern part of the park was closed for seasonal maintenance, this means the park is currently completely shut, although workers from Utah State Parks are now attempting to reopen the southern part of the park as quickly as possible.

Deisel is believed to have been prevented from entering the reservoir itslef by a series of beaver dams, though scientists from the Utah Division of Water Quality are monitoring the situation closely. Sadly the Beaver dams are likely to be demolished as part of the cleanup operation. Two oiled beavers have been brought into local rescue centers since Monday, it is unclear how the rest of the local population has been affected.

Workers from Chevron began excavating the area around the pipeline on Tuesday, vacuuming spilt fuel from the ditch in the process. The United States Environmental Protection Agency also have a team on the ground, and have expressed concerns about the possibility of contamination enetering the reservoir or affecting migratory birds, including Snow Geese, Tundra Swans and Pelicans, which are expected to start ariving at the site within the next two weeks.

Workers from Chevron excavating the damaged pipeline on Wednesday. Salt Lake Tribune.

The pipeline is believed to have leaked at least 83 000 liters of diesel, and it is not clear that the leak has been halted. The area near the pipeline has been isolated from the reservoir by a series of absorbant booms.Chevron have been ordered not to reopen the pipeline without permission from U.S. Transportation Department’s Pipeline and Hazardous Materials Safety Administration.

This is the third serious spill from a pipeline in Utah in three years; it follows on from two spills near Red Butte Garden in 2010. Utah is crossed by a network of aging pipelines (this weeks leak comes from a pipeline laid in 1950), and environmental groups such as Friends of the Great Salt Lake have raised questions as to whether this is a sustainable situation.

See also North Sea oil rig partially evacuated following leakDutch court fines Shell over pollution in ther Niger DeltaPipeline explosion in Ogun State, southwest NigeriaGas pipeline explosion in West Virginia and Amnesty International reports on the 2012 Bodo Oil Spill.

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