1 / 11

IGOS Geohazards Workshop

IGOS Geohazards Workshop. Science working group report. Moderator: Rosalind Helz Rapporteurs: Alik Ismail-Zadeh, Simeon Kostyanev, Pierre Briole WG members: Pascale Ultré-Guérard, Peter Collins, Valério Tramutoli, François Schindélé. Issues in earthquakes.

stella
Download Presentation

IGOS Geohazards Workshop

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. IGOS Geohazards Workshop Science working group report Moderator: Rosalind Helz Rapporteurs: Alik Ismail-Zadeh, Simeon Kostyanev, Pierre Briole WG members: Pascale Ultré-Guérard, Peter Collins, Valério Tramutoli, François Schindélé

  2. Issues in earthquakes • Location and size of the active faults (including blind faults) and the history of earthquakes on each. • Is the seismic cycle model realistic or not ? • Balance between seismic and aseismic deformation • Mapping and interpretation of strain changes produced by an earthquake and the implication for seismic hazard • Detection of precursors and understanding the physical processed that generated them inside Earth

  3. Issues in volcanoes • To know the structure of the magmatic plumbing system. • To distinguish between signal indicating an unrest that will lead to an eruption and “noise” (like changes in the geothermal system). • Will precursors in long dormant volcanoes be similar to those in more active volcanoes ? Will precursors for “super-volcano” eruptions be similar ? • To predict the characteristics of an eruption once it has been forecast (including size) • To predict the evolution of an eruption once it has started

  4. Issues in ground instabilities • Landslides • To detect unknown landslides, to develop landslides inventories • To be able to detect small motions before accelerations • To establish threshold conditions for triggering landslides from rainfall • Subsidence • To detect unknown subsiding areas • To be able to detect changes in subsidence rate

  5. Compound geohazards • Triggering of landslides by earthquakes or volcanic eruptions • Triggering of a volcanic eruption by an earthquake • Occurrence of lahars after large explosive eruptions • Generation of tsunamis

  6. Issues in tsunamis • To determine quickly the critical parameters of an earthquake with tsunamigenic potential: • Depth of the upper edge of the fault below the sea bottom • Length of the rupture • Slip distribution on the fault • To be able to directly detect a tsunami • To forecast amplitude and time of arrival of the waves reaching the coast

  7. Social issues for the geohazards • We need to learn how to maintain awareness in the exposed population between rare events. • We need to learn more about the behaviour of populations in areas exposed to geological risk • We need to understand better the behaviour of populations after major disasters. • We need cost/benefit analysis for the different geohazards

  8. Additional issues discussed by the group but out of scope of IGOS-G • Impact of very large eruptions on global weather • Impact of long term (>0.1Myr) climate change, sea level change, ice sheets evolution on the evolution of hazard

  9. Development/validation of new techniques • IGOS encourages further development and expansion of quantitative deformation measurement techniques • Continuity of InSAR missions is crucial • Combination of GPS and InSAR • Need better tropospheric correction • IGOS encourages development of ground based radars and lidars • IGOS encourages a critical evaluation of the DEMETER mission that is aimed to detect electro-magnetic signals associated with earthquakes. In particular GPS derived ionospheric anomalies should be used in this evaluation. • IGOS encourages more research on techniques to evaluate the location and movement of fluids in the crust • IGOS encourages the development of cross validation methods to combine ground and space based data

  10. Partnership and networking • IGOS recognizes that good research requires strong partnership among: • Observatories and operational agencies • Research scientists • Space agencies • Industry building ground and space sensors • Emergency authorities • IGOS recognises that networking activities are especially important to support near real time analysis and modelling of data

  11. Some specific recommendations to help science for geohazards • Data bases • IGOS recommends that volcano observatories participate in the development of “WOVOdat” project. • IGOS recognizes the need for improved historical archives for all geohazards (comparable to the Global Volcanism Project). • IGOS encourages co-location of sensors (example seismic and GPS data acquired at the same location) • IGOS encourages the development of facilities to feed science community with InSAR and PS-InSAR interferograms produced on a routine basis

More Related