Deformation Due to Magma Movement and Ice Unloading at Katla Volcano, Iceland, Detected by Persistent Scatterer Insar
نویسندگان
چکیده
Katla volcano is situated in the south of Iceland, and is largely covered by the Mýrdalsjökull ice cap. Historically, Katla is one of the most active of Iceland’s volcanoes, with 20 eruptions in the last 1100 years, the last one being in 1918. The proximity of populated areas and international flight paths makes prediction of the timing and character of any future eruption particularly important. Between late 2000 and early 2005 there was increased seismicity beneath the caldera and west flank of Katla, accompanied by upwards and radially outwards movement of two continuous GPS stations north of Katla caldera. This motion has since ceased, but two continuous GPS sites on the southern flank have been trending upwards and south-southwest since 2000, and this motion continues to the present. We use both persistent scatterer and combined multiple acquisition InSAR techniques to analyse ENVISAT ASAR data acquired from September 2003 to July 2006, and ERS data acquired between 1995 and 2003, to determine line-of-sight displacements for the area surrounding Katla. The signal we see is consistent with a response to ice unloading, and intrusion of magma or fluids is not required to explain the data. We don’t, however, rule out shallow intrusion beneath the caldera causing local deformation that is not visible on the volcano flanks. We also identify possible local landsliding occurring on the volcano flanks.
منابع مشابه
Corrigendum: Crustal movements due to Iceland’s shrinking ice caps mimic magma inflow signal at Katla volcano
Many volcanic systems around the world are located beneath, or in close proximity to, ice caps. Mass change of these ice caps causes surface movements, which are typically neglected when interpreting surface deformation measurements around these volcanoes. These movements can however be significant, and may closely resemble movements due to magma accumulation. Here we show such an example, from...
متن کاملOn the absence of InSAR-detected volcano deformation spanning the 1995–1996 and 1999 eruptions of Shishaldin Volcano, Alaska
Shishaldin Volcano, a large, frequently active basaltic-andesite volcano located on Unimak Island in the Aleutian Arc of Alaska, had a minor eruption in 1995–1996 and a VEI 3 sub-Plinian basaltic eruption in 1999. We used 21 synthetic aperture radar images acquired by ERS-1, ERS-2, JERS-1, and RADARSAT-1 satellites to construct 12 coherent interferograms that span most of the 1993–2003 time int...
متن کاملMeasurement and interpretation of subtle deformation signals at Unimak Island from 2003 to 2010 using weather model-assisted time series InSAR
A 7 year time series of satellite radar images over Unimak Island, Alaska—site of Westdahl Volcano, Fisher Caldera, and Shishaldin Volcano—was processed using a model-free Persistent Scatterer Interferometry technique assisted by numerical weather prediction model. The deformation-only signals were optimally extracted from atmosphere-contaminated phase records. The reconstructed deformation tim...
متن کاملClimate effects on volcanism: influence on magmatic systems of loading and unloading from ice mass variations, with examples from Iceland.
Pressure influences both magma production and the failure of magma chambers. Changes in pressure interact with the local tectonic settings and can affect magmatic activity. Present-day reduction in ice load on subglacial volcanoes due to global warming is modifying pressure conditions in magmatic systems. The large pulse in volcanic production at the end of the last glaciation in Iceland sugges...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2007