Lava flow hazard at Fogo Volcano, Cabo Verde, before and after the 2014–2015eruption

Abstract. Lava flow simulations help to better understand volcanic hazards and may assist emergency preparedness at active volcanoes. We demonstrate that at Fogo Volcano, Cabo Verde, such simulations can explain the 2014–2015 lava flow crisis and therefore provide a valuable base to better prepare for the next inevitable eruption. We conducted topographic mapping in the field and a satellite-based remote sensing analysis. We produced the first topographic model of the 2014–2015 lava flow from combined terrestrial laser scanner (TLS) and photogrammetric data. This high-resolution topographic information facilitates lava flow volume estimates of 43.7 ± 5.2 × 106 m3 from the vertical difference between pre- and posteruptive topographies. Both the pre-eruptive and updated digital elevation models (DEMs) serve as the fundamental input data for lava flow simulations using the well-established DOWNFLOW algorithm. Based on thousands of simulations, we assess the lava flow hazard before and after the 2014–2015 eruption. We find that, although the lava flow hazard has changed significantly, it remains high at the locations of two villages that were destroyed during this eruption. This result is of particular importance as villagers have already started to rebuild the settlements. We also analysed satellite radar imagery acquired by the German TerraSAR-X (TSX) satellite to map lava flow emplacement over time. We obtain the lava flow boundaries every 6 to 11 days during the eruption, which assists the interpretation and evaluation of the lava flow model performance. Our results highlight the fact that lava flow hazards change as a result of modifications of the local topography due to lava flow emplacement. This implies the need for up-to-date topographic information in order to assess lava flow hazards. We also emphasize that areas that were once overrun by lava flows are not necessarily safer, even if local lava flow thicknesses exceed the average lava flow thickness. Our observations will be important for the next eruption of Fogo Volcano and have implications for future lava flow crises and disaster response efforts at basaltic volcanoes elsewhere in the world.

[1]  J. Lockwood,et al.  Applications of GIS to the estimation of lava flow hazards on Mauna Loa Volcano, Hawai'i , 2013 .

[2]  M. Favalli,et al.  DOWNFLOW code and LIDAR technology for lava flow analysis and hazard assessment at Mount Etna , 2011 .

[3]  J. Zumberge,et al.  Precise point positioning for the efficient and robust analysis of GPS data from large networks , 1997 .

[4]  Paolo Papale,et al.  Lava flow hazard at Nyiragongo Volcano, DRC , 2009 .

[5]  V. Troll,et al.  Volcanic and structural evolution of Pico do Fogo, Cape Verde , 2015 .

[6]  Delphine Grancher,et al.  Reducing volcanic risk on Fogo Volcano, Cape Verde, through a participatory approach: which outcome? , 2013 .

[7]  M. Favalli,et al.  Simulating the area covered by lava flows using the DOWNFLOW code , 2015, Special Publications.

[8]  C. Kilburn.  Lava Flow Hazards and Modeling , 2015 .

[9]  M. Favalli,et al.  Forecasting lava flow paths by a stochastic approach , 2005 .

[10]  I. Stewart,et al.  The Archaeology of Geological Catastrophes , 2000 .

[11]  Paolo Papale,et al.  Lava flow hazard and risk at Mt. Cameroon volcano , 2012, Bulletin of Volcanology.

[12]  Simon Day,et al.  A past giant lateral collapse and present-day flank instability of Fogo, Cape Verde Islands , 1999 .

[13]  Matthias Winkler,et al.  MINUIT User's Guide , 2004 .

[14]  M. Favalli,et al.  Uncertainties in lava flow hazard maps derived from numerical simulations: the case study of Mount Etna , 2013 .

[15]  Fabien Albino,et al.  High‐resolution TanDEM‐X DEM: An accurate method to estimate lava flow volumes at Nyamulagira Volcano (D. R. Congo) , 2015 .

[16]  Joerg M. Schaefer,et al.  Hazard potential of volcanic flank collapses raised by new megatsunami evidence , 2015, Science Advances.

[17]  T. Wright,et al.  The 2014–2015 eruption of Fogo volcano: Geodetic modeling of Sentinel‐1 TOPS interferometry , 2015 .

[18]  P. Okubo,et al.  The 2014-2015 Pahoa lava flow crisis at Kilauea Volcano, Hawai'i; disaster avoided and lessons learned , 2016 .

[19]  Germán Padilla,et al.  Diffuse volcanic gas emission and thermal energy release from the summit crater of Pico do Fogo, Cape Verde , 2015, Bulletin of Volcanology.

[20]  M. James,et al.  Detecting the development of active lava flow fields with a very‐long‐range terrestrial laser scanner and thermal imagery , 2009 .

[21]  Gaetana Ganci,et al.  Quantifying Effusion Rates at Active Volcanoes through Integrated Time-Lapse Laser Scanning and Photography , 2015, Remote. Sens..

[22]  M. Favalli,et al.  Dispersion index of topographic surfaces , 2012 .

[23]  R. Hanssen.  Radar Interferometry: Data Interpretation and Error Analysis , 2001 .

[24]  M. Poland.  Time‐averaged discharge rate of subaerial lava at Kīlauea Volcano, Hawai‘i, measured from TanDEM‐X interferometry: Implications for magma supply and storage during 2011–2013 , 2014 .

[25]  Simone Tarquini,et al.  A new approach to risk assessment of lava flow at Mount Etna , 2009 .

[26]  Maria Luisa Carapezza,et al.  The control of lava flow during the 1991 1992 eruption of Mt. Etna , 1993 .

[27]  Simone Tarquini,et al.  Mapping and DOWNFLOW simulation of recent lava flow fields at Mount Etna , 2011 .

[28]  Simone Tarquini,et al.  Evolution of an active lava flow field using a multitemporal LIDAR acquisition , 2010 .

[29]  C. Del Negro,et al.  MAGFLOW: a physics-based model for the dynamics of lava-flow emplacement , 2015, Special Publications.

[30]  Paolo Papale,et al.  Lava flow hazard at Nyiragongo volcano, D.R.C. , 2009 .

[31]  C. Adam,et al.  Refined models of gravitational potential energy compared with stress and strain rate patterns in Iberia , 2014 .

[32]  Adrian W. Bowman,et al.  Computational aspects of nonparametric smoothing with illustrations from the sm library , 2003, Comput. Stat. Data Anal..

[33]  Andrew J. L. Harris,et al.  Simulating the thermorheological evolution of channel-contained lava: FLOWGO and its implementation in EXCEL , 2015, Special Publications.

[34]  Z. Altamimi,et al.  ITRF2008: an improved solution of the international terrestrial reference frame , 2011 .

[35]  P. Rosen,et al.  Analysis of Active Lava Flows on Kilauea Volcano, Hawaii, Using SIR-C Radar Correlation Measurements , 1996 .

[36]  C. Oppenheimer,et al.  Terrestrial laser scanning observations of geomorphic changes and varying lava lake levels at Erebus volcano, Antarctica , 2015 .

[37]  Falk Amelung,et al.  InSAR observations of the 1995 Fogo, Cape Verde, eruption: Implications for the effects of collapse events upon island volcanoes , 2002 .

[38]  C. Del Negro,et al.  Lava flow hazard modeling during the 2014–2015 Fogo eruption, Cape Verde , 2015 .

[39]  A. Hooper,et al.  High‐resolution digital elevation model from tri‐stereo Pleiades‐1 satellite imagery for lava flow volume estimates at Fogo Volcano , 2016 .

[40]  J. Kauahikaua,et al.  Natural hazards and risk reduction in Hawai'i: Chapter 10 in Characteristics of Hawaiian volcanoes , 2014 .

[41]  M. Westoby,et al.  ‘Structure-from-Motion’ photogrammetry: A low-cost, effective tool for geoscience applications , 2012 .

[42]  A. Cappello,et al.  QVAST: a new Quantum GIS plugin for estimating volcanic susceptibility , 2013 .

[43]  Orlando Ribeiro.  A ilha do fogo e as suas erupções , 1960 .

[44]  F. Loddo,et al.  Integration of ground-based laser scanner and aerial digital photogrammetry for topographic modelling of Vesuvio volcano , 2007 .

[45]  S. Day,et al.  Comparison and cross-checking of historical, archaeological and geological evidence for the location and type of historical and sub-historical eruptions of multiple-vent oceanic island volcanoes , 2000, Geological Society, London, Special Publications.

[46]  P. Worsley.  Physical geology of the Fogo volcano (Cape Verde Islands) and its 2014–2015 eruption , 2015 .

[47]  Geert Verhoeven,et al.  Taking computer vision aloft – archaeological three‐dimensional reconstructions from aerial photographs with photoscan , 2011 .

[48]  A. Harris,et al.  Effusion rate controls on lava flow length and the role of heat loss: a review , 2009 .

[49]  A. Harris,et al.  Lava effusion rate definition and measurement: a review , 2007 .

[50]  Michael P. Poland,et al.  Hawaiian Volcanoes: From Source to Surface , 2015 .

[51]  L. Fortuna,et al.  Simulations of the 2004 lava flow at Etna volcano using the magflow cellular automata model , 2008 .

[52]  Simona Zoffoli,et al.  Multi-payload Multi-platform Tactical Monitoring and Evaluation of the 2014 Eruption of Fogo, Cabo Verde , 2015 .

[53]  R. Spence,et al.  Volcanic risk assessment: Quantifying physical vulnerability in the built environment , 2014 .

[54]  Michael P. Poland,et al.  Tracking lava flow emplacement on the east rift zone of Kīlauea, Hawai‘i, with synthetic aperture radar coherence , 2012 .