Sciency Thoughts: Styria

Monday, 9 March 2020

Avalanches kill six people in two separate incidents in Austria.

Six people have died in two different avalanche incidents in Austria on Sunday 8 March 2020. The first incident happened at about 9.30 am local time in the Dachstein area, on the border between Upper Austria and Styria, to the southeast of Salzberg, when five tourists, thought to have been from the Czech Republic, were hit by an avalanche while snowshoeing; all were dead by the time emergency services arrived. The second incident happened at about 11.30 am, on Mount Großglockner in the Carinthian Region, where a 33-year-old police officer was hit by an avalanche while on a training exercise, and died of his injuries before he could be removed from the Mountain.

Mount Großglockner, in summer 2013. Wikimedia Commons.

Avalanches are caused by the mechanical failure of snowpacks; essentially when the weight of the snow above a certain point exceeds the carrying capacity of the snow at that point to support its weight. This can happen for two reasons, because more snow falls upslope, causing the weight to rise, or because snow begins to melt downslope, causing the carrying capacity to fall. Avalanches may also be triggered by other events, such as Earthquakes or rockfalls. Contrary to what is often seen in films and on television, avalanches are not usually triggered by loud noises. Because snow forms layers, with each layer typically occurring due to a different snowfall, and having different physical properties, multiple avalanches can occur at the same spot, with the failure of a weaker layer losing to the loss of the snow above it, but other layers below left in place - to potentially fail later.

Diagrammatic representation of an avalanche, showing how layering of snow contributes to these events. Expedition Earth.

Iphiculus eliasi: A new species of Iphiculid Crab from the Miocene of Austria.

Iphiculid Crabs are today found only in the Indian Ocean and western Pacific, and with a fossil record from Borneo. However they are closely related to the Leucosid Crabs (Pebble or Nut Crabs), which are found across the Old World from the west coasts of Europe and Africa to the shores of Australia, and the Folguerolsid Crabs, which are known only from the Miocene of Spain.

In a paper published in the journal Zootaxa on 31 October 2016, Matúš Hyžný of the Department of Geology and Palaeontology at Comenius University and the Geological-paleontological Department at the Natural History Museum in Vienna and Martin Gross of the Department for Geology & Palaeontology at Universalmuseum Joanneum describe an Iphiculid Crab from the Miocene of Wetzelsdorf in the state of Styria, Austria.

The new species is placed in the extant genus Iphiculus and given the specific name eliasi, in honour of Eliáš Hyžný, the son of Matúš Hyžný. It is described from three specimens, one almost intact carapace and two partial ones, the intact specimen measuring 15.7 mm in length and 19.0 mm in width, and all covered in tubercles.

Iphiculus eliasi. (A–D) First specimen in dorsal (A), posterodorsal (B), frontal (C), and posterior view (D); (E) second specimen in dorsal view. Specimens were coated with ammonium chloride prior the photography. All specimens to scale. Hyžný & Gross (2016).

The discovery of Iphiculus eliasi from Miocene deposits in Austria combined with a possible Iphiculid Crab from the Miocene of Catalonia and the presence of the related Leucosid and Folguerolsid Crabs in the Miocene of Europe suggests that the Iphiculids, now found predominantly in Southeast Asia and Indonesia, may have originated in what is now the Mediterranean Basin and spread eastwards along the Tethys Seaway, vanishing from the western part of its range as that seaway closed (prior to the opening of the Mediterranean), then subsequently spread back around the shores of Asia to attain their current distribution.