Short articles

This section is focused to collect "short articles" of general interest for the IAVCEI members. Anyone interested in publishing a "short article" should contact A.Geyer (ageyertraver@gmail.com).

INDEX

Workshop on large-scale experiments for volcano processes and geohazards – research priorities and infrastructure concepts (PDF)

 

Greg A. Valentine (University at Buffalo), Costanza Bonadonna and Irene Manzella (Université de Genève), Amanda Clarke (Arizona State University), Pierfrancesco Dellino (Università di Bari)


Some of the least understood and most hazardous geologic processes involve complex multiphase flows, particularly those related to explosive volcanic eruptions. These phenomena inherently involve a wide range of characteristic length and time scales, and processes that are coupled across those scales in a range of flow regimes. For example, a pyroclastic density current’s (PDC; a.k.a. pyroclastic flows and surges) behavior is governed in a complex way by the interactions between individual particles (~10-4-10-1 m, ~10-1-101 s) as well as by turbulent mixing with surrounding air (~10-2-102 m, 1-102 s). Material properties within individual flows can vary over huge ranges. A second example is the large-scale interaction between shearing magma and external water in a volcanic conduit, where the starting material is viscous melt and upon fragmentation the material properties range from brittle glass to steam. There are four ways in which we explore these processes: observations in real time, observations of deposits after an event, bench top and analog experiments that try and recreate conditions that occur at much larger scales, and numerical models. Data collection from active volcanic flows is greatly limited by the unpredictability of the events and the dangerous conditions they produce; and, even if measurements can be made, the initial and boundary conditions of the eruptive flows are poorly constrained and this limits the physical insight that can be gained. Data measured on deposits or other eruptive products, such as individual clasts,
provide important, but indirect information on the parent processes. While analog experiments provide many insights into the flows, a fundamental difficulty with multiphase volcanic processes is that they cannot be strictly scaled to the bench top. Numerical modeling is of growing importance in predicting and interpreting volcanic flows. However, such modeling is limited by two important factors: (1) our inability to resolve all the scales and processes due to computer capacity and to a lack of appropriate “sub-models” (i.e., constitutive models) for processes such as multiphase turbulence coupled with granular flow, coupled solid-fluid mechanics, and extremely rapid processes that include phase changes; and (2) the difficulty of validating complex numerical models, which requires high-quality measurements on real flows that incorporate the dynamics represented in the governing conservation equations.. ...READ MORE

 

United Nations International Strategy for Disaster Reduction Secretariat (UNISDR)Geneva, Switzerland

 

RISK REDUCTION PLANS NEEDED TO MINIMIZE VOLCANIC DISRUPTION Although air travel in Europe is starting to resume after ash from Iceland's Eyjafjallajökull volcano grounded flights for almost a week, thousands of travellers continue to be affected and more delays possible with the threat of further eruptions.

“We only realize how disruptive hazards can be when they have already happened,” Margareta Wahlström, the UN Secretary-General's Special Representative for Disaster Risk Reduction, said Thursday. “The volcano eruption is an example of a rare but largely disruptive event that exposes our key infrastructure vulnerability.”

To minimize severe disruptions in the future, the UN's International Strategy for Disaster Reduction (ISDR) is urging European governments to take more action to integrate volcano risk as part of their air travel policies and legislation. Through the Hyogo Framework for Action – a global plan for disaster risk reduction efforts – the UNISDR is working to ensure greater coordination and interaction between decision-makers and the scientific community.

“This situation demonstrates that it is important to have international and regional contingency plans in addition to local or national ones to assess volcano risks,” said Wahlström.

While the Eyjafjallajökull eruption was not a relatively big one compared with others in the past, it has caused chaos on a massive scale. Other volcanoes in Europe, such as Italy's Vesuvius and Iceland's much bigger Katla, would create far more disruption if they were to erupt today, according to Henry Gaudru, President of the European Volcanologist Society, speaking at a UNISDR briefing in Geneva.

Volcanologists will meet from 31 May to 4 June 2010 in Tenerife, Canary Islands, at an international conference to discuss volcanic crisis management, particularly their effect on megacities. “This meeting will be a good opportunity to discuss more action,” said Margareta Wahlström. “As the Pinatubo eruption in the Philippines showed us in 1991 as well as other ones since then, volcano risks must be urgently considered for their huge economic and social impacts and be integrated in urban planning, early warning systems and preparedness plans.”

The International Air Transport Association (IATA) has reported that airport closures in Europe have caused losses of close to US$2 billion, and left tens of thousands of travellers stranded. The final economic cost of the natural disaster is still being assessed.

UNISDR Volcanologist contact : Henry Gaudru, European Volcanological Society, UNISDR scientific adviser for volcanic risk mitigation - hgaudru@sveurop.org , http://www.sveurop.org - http://www.unisdr.org

 

 

Erionite Exposure and Mesothelioma Cancer (PDF)

 

The naturally occurring mineral erionite is usually found in volcanic ash that has been altered by weathering and ground water. Typically, the substance is located throughout the hollows of rock formations where asbestos can also be found. It usually varies in color from white to clear, and is said to feel and look like wool.

 

 

Although the properties of erionite have been compared to those of asbestos, the U.S. Environmental Protection Agency (EPA) has yet to regulate the toxic mineral. In fact, the inhalation of erionite poses some of the same health effects that are associated with asbestos, including lung cancer and mesothelioma .

Mesothelioma is a type of cancer that develops in the mesothelial cells found in the body. Pleural mesothelioma , the most common type of mesothelioma cancer, develops in the mesothelial lining of the lungs. After attaching to the lungs, many of these erionite and asbestos fibers can remain in place because the body has a difficult time expelling them.

Other areas that are known to be afflicted by the disease, but are less likely to, include the mesothelial linings of the abdomen and heart. Due to an extended latency period associated with mesothelioma, a diagnosis usually occurs during the latest stages of development, which often leads to mesothelioma treatments being more palliative than curative.

According to the EPA, erionite fibers exhibit the same size and structure of asbestos particles. Because of this, any disturbance to the mineral can present serious hazards and lead to toxic fibers being released into the air. In Cappadocia, Turkey, an unprecedented mesothelioma epidemic caused 50% of all deaths in three small villages.

The mesothelioma epidemic was attributed to erionite stones from volcanic rocks used in homes. At first, the erionite-containing stones were strictly noted as the cause of death, however, it has recently been discovered that erionite exposure typically causes mesothelioma in those with a genetic predisposition. These findings have shown that genetically predisposed individuals can actually develop malignant mesothelioma at rates much higher than those without a genetic predisposition.

Approximately 2,000 to 3,000 cases of mesothelioma are currently diagnosed each year, and those numbers are expected to rise in the very near future. If you or a loved one has been exposed to erionite or asbestos, it is important to seek the advice of a medical doctor. For more information on mesothelioma, please visit Asbestos.com.

References
http://www.inctr.org/publications/2003_v04_n01_s03.shtml
http://www.health.state.nd.us/EHS/Erionite/General/Erionite_Fact_Sheet.pdf