Mount Etna changes over time, new INGV map reveals
Researchers at the National Institute of Geophysics and Volcanology have published a topographic map, using cutting-edge technology, which shows the morphological changes that affected Mount Etna from 2007 to 2010. The study was published in the journal Geophysical Research Letters.
Mount Etna, the most active volcano in Europe, has been affected by morphological changes over time, particularly at the summit vents. It was revealed by a new topographic map developed by researchers at the National Institute of Geophysics and Volcanology (INGV) of the sections of Catania and Pisa, who have recently published the results of their research in the journal Geophysical Research Letters.
To measure the extent of the morphological changes that affected Mount Etna between 2007 and 2010, the INGV researchers used the LiDAR technology (Light Detection And Ranging): an “active” remote sensing system used to carry out high-resolution topographic aerial surveys. To use this technology, a laser scanning unit, composed of a laser transmitter, a receiver and a data acquisition and processing system, is mounted on an aircraft, which allows the acquisition of high-speed and high space resolution data.
“Soil surveys at an active volcano”, explains Marco Neri, researcher at INGV in Catania and study coordinator, “often provide results that, by their very nature, are subject to some degree of uncertainty. Today, modern technology provides us with increasingly sophisticated tools, able to obtain precious and extremely precise information about the surface of a volcano remotely, that is, without coming into direct contact with it”.
Using LiDAR data, the researchers created a digital elevation model (DEM) of Mount Etna reproducing its morphology in June 2007 and September 2010. Comparing the two maps, the researchers also measured with great accuracy the volume changes and the morphological changes occurred at the summit area of the volcano and along the Valle del Bove, which showed that, in about three years, over 86 million cubic meters of volcanic products accumulated in the studied area, most of which (about 74 million) were emitted by an eruptive fissure that opened on the western flank of the Valle del Bove, which was profoundly changed.
“Quantifying the changes occurred at Mount Etna is of fundamental importance to understand recent eruptive dynamics”, adds Alessandro Fornaciai, researcher at INGV in Pisa. “Aerial LiDAR surveys, thanks to the overall view and accuracy that they provide, are extremely useful to obtain, through appropriate corrections and elaborations, temporal sequences of high-resolution digital elevation models (DEMs) of the area studied”.
“The new 2010 topography represents a starting point for the calculation of subsequent morphological and structural changes of the volcano”, adds Boris Behncke, researcher at INGV in Catania. “Important changes such as those occurred from January 2011 on, which gave rise to a long series of summit eruptive events, evolving, in the following years, into the new cone of the Southeast Crater, 300 m high and grown faster than any other volcano in recorded history”.