Volcanoes - Astronomy News

Blobrana

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Posts: 131433

Date: Jan 23 15:47 2007

Mud Volcanoes	Permalink

The first scientific report into the causes and impact of Lusi, the Indonesian mud volcano, reveals that the 2006 eruption will continue to erupt and spew out between 7,000 and 150,000 cubic metres of mud a day for months, if not years to come, leaving at least 10 km2 around the volcano vent uninhabitable for years and over 11,000 people permanently displaced. The paper by a Durham University-led team and published in the February issue of US journal, GSA Today, reveals that the eruption was almost certainly manmade and caused by the drilling of a nearby exploratory borehole looking for gas, reinforcing the possible explanation in a UN report from July last year. The mud volcano, known locally as ‘Lusi’, has been erupting for 239 (4) days and has continued to spew between 7,000 and 150,000 cubic metres of mud out every day, destroying infrastructure, razing four villages and 25 factories. Thirteen people have also died as a result of a rupture in a natural gas pipeline that lay underneath one of the holding dams built to retain the mud. It first erupted on 29 May 2006 in the Porong subdistrict of Sidoarjo in Eastern Java, close to Indonesia’s second city of Surabaya. The team of mud volcano and pressure experts, who analysed satellite images of the area for their study, propose that a local region around the central volcano vent will collapse to form a crater. In addition an area of at least the dimensions of the flow (10km2) will probably sag over the next few months and years. Seepage of mud and water are common on earth but usually a preventable hazard when exploring for oil and gas. Mud volcano expert, Professor Richard Davies of Durham University’s Centre for Research into Earth Energy Systems (CeREES) comments: “It is standard industry procedure that this kind of drilling requires the use of steel casing to support the borehole, to protect against the pressure of fluids such as water, oil or gas. In the case of Lusi a pressured limestone rock containing water (a water aquifer) was drilled while the lower part of the borehole was exposed and not protected by casing. As a result rocks fractured and a mix of mud and water worked its way to the surface. Our research brings us to the conclusion that the incident was most probably the result of drilling.” The team from Durham, Cardiff and Aberdeen Universities and GeoPressure Technology Ltd, an Ikon Science company, has essentially discounted the effect of an earthquake which occurred in the region two days prior to the mud volcano as the cause of the eruption. This is based on the time-lapse between the earthquake and the eruption, the fact that there were no other mud volcanoes in the region following the earthquake and through comparison with other geological examples. Source Durham University __________________

Blobrana

L

Posts: 131433

Date: Dec 12 03:06 2006

Four submarine mud volcanoes	Permalink

A team of Thai and German marine geologists has found four submarine mud volcanoes about 200 kilometres from Phuket, the team leader announced yesterday. Dr Anon Sanitwong na Ayutthaya, of Chulalongkorn University, said tests had been carried out for 16 days ending on December 6 with support from the German government and from the National Marine Geology Institute in Keil, Germany. The team surveyed the seabed for 1,500 square kilometres at a depth of 1,000 to 2,800 metres at the edge of the continental shelf, about 300km from Phuket. "We have good news … the team detected four mud volcanoes in the area" - Dr Anon Sanitwong na Ayutthaya. Read more __________________

Blobrana

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Posts: 131433

Date: Dec 11 14:18 2006

Mud Volcanoes	Permalink

Research on underwater mud volcanoes One of the subjects being explored by HERMES is mud volcanoes, and more specifically underwater mud volcanoes. Mud volcanoes are cone-shaped formations of sediment, of variable size. They are composed of a mixture of fluids (generally water and gases) and mud (undercompacted clay), which flow from one or more vent holes in the middle of the crater. During an eruption, mud volcanoes emit large amounts of methane. Mud volcanoes are found on land and underwater. The latter are the subject of this new report for television stations. Indeed, researchers are studying the impact on climate change of the gases emitted by these volcanoes. They have discovered that the immediate surroundings of these volcanoes are constituted of micro-organisms, of which 99% are still unidentified today, and some of which feed on methane, hydrogen sulphide and other gases, preventing them from being released into the sea and consequently rising to the surface. The oceans are home to 90% of life on earth, which is why it is essential to study their functions. That is precisely the aim of the HERMES project (Hotspot Ecosystem Research on the Margins of European Seas) initiated under the Sixth European Research Framework Programme. HERMES is one of the biggest integrated research projects for the study of ecosystems in the depths of European waters. Launched in April 2005 as part of the 6th European Research Framework Programme, HERMES is run by a consortium made up of 45 European partners, divided into 11 distinct working groups. This international and multidisciplinary project financed by the European Commission, gathers experts in biodiversity, geology, sedimentology, physical oceanography, microbiology, biogeochemistry and socio-economic. It constitutes the first major attempt to achieve a global understanding of ecosystems in the depths of European waters and their environment. The study sites are located in the Arctic, the Black Sea, the Baltic Sea, the Atlantic and the Mediterranean. The main research sites are currently located in: * Nordic waters * the waters of Rockall (west of the United Kingdom) * the Portuguese Atlantic seaboard * the Gulf of Cadiz * the eastern Mediterranean * the Black Sea * the western Mediterranean The approach is identical for each site: * Acquire a better understanding of the natural conductors which control ocean ecosystems * Acquire a better understanding of how biodiversity works and of critical ecosystems * Forecast changes which will affect the processes involved in biodiversity and ecosystem * Develop strategies for the sustainable use of marine resources Read more __________________

Blobrana

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Posts: 131433

Date: Sep 6 19:10 2006

RE: Volcanoes	Permalink

The team's study looked at a range of material thrown out from the US mountain in the 1980s, and from more recent events at Shiveluch in Russia. The samples contained small glassy inclusions - minute droplets of once molten material that came up with the rising magma but whose contents remained unaltered. The scientists probed these tiny volcanic blobs to determine what conditions must have been like deep underground. Read more __________________

Blobrana

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Posts: 131433

Date: Sep 6 17:56 2006

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New insights into what might trigger the eruption of Mount St Helens and other potentially explosive volcanoes are reported today in Nature by scientists working at the University of Bristol, UK.

Professor Jon Blundy and colleagues show that as magmas crystallise they heat up rather than cool down, as previously thought. And the more a magma crystallises the hotter it gets – by up to 100 °C. This ability to self-heat may provide a trigger for eruptions.

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