Methods and results

 

• Subproject 1: Real-time evaluation of earthquake-related-processes and development of database, and coordination of the project as a whole
  • Task 1: Database, development and service
    • Task 1.1: Data collection
    • Task 1.2: The database access
  • Task 2: To map seismically active minifaults of the seismic fault systems
  • Task 3: To search for time and space patterns in the multiplicity of information in the SIL data
  • Task 4: Introduction of new algorithms into the alert system and other evaluations of the SIL system
  • Meetings and conferences
• Subproject 2: Development of methods using microearthquakes for monitoring crustal instability
  • Task 1: Methods for subcrustal mapping of faults
  • Task 2: Methods for monitoring crustal wave velocities from microearthquakes
  • Task 3: Methods for monitoring the local rock stress tensor
  • Task 4: Methods for monitoring of stable/unstable fault movements
  • Task 5: Methods for statistical analysis of the space/time distribution of microearthquakes and earthquakes
  • Task 6: Development of a method for acqusition of continuous GPS data at the SIL stations
  • Meetings and conferences
• Subproject 3: Monitoring stress changes before earthquakes using seismic shear-wave splitting
  • Task 1: Identify optimal stations and search for precursors
  • Task 2: Station/EQ relationship
  • Task 3: Developing routine techniques
  • Task 4: Identify optimum areas
  • Meetings and conferences
• Subproject 4: Borehole monitoring of fluid-rock interaction
  • Subpart 4A: Geophysical loggings
    • Task 1: Logging activities
    • Task 2: Check for changes - results from repeated logging
    • Tasks 3 and 4: Evaluation of measuring results
    • Acknowledgements
  • Subpart 4B: Radon related to seismicity in the South Iceland seismic zone
    • Task 1: Build an improved LSC apparatus to measure the radon content of water and gas samples
    • Task 2: Revive the radon sampling program in South Iceland
• Subproject 5: Active deformation determined from GPS and SAR
  • Subpart 5A: SAR interferometry
    • Task 1: Analysis of SAR images from the ERS-1 and ERS-2 satellites
  • Subpart 5B: GPS geodesy
    • Task 1: Installation
    • Task 2: Deformation rates
• Subproject 6: Formation and development of seismogenic faults and fault populations
  • Subpart 6A: Paleostresses
    • Task 1: Determine the paleostress tensor
      • Detailed analysis of focal mechanisms of earthquakes and recent faulting in the central part of the SISZ (work carried out with Gudmundsson and Rögnvaldsson)
      • Seismi-tectonic studies in the whole SISZ (work carried out with Gudmundsson and Rögnvaldsson)
      • Stress tensor determination from focal mechanisms: development of new methodology, especially aiming at solving the problem of the choice between the nodal planes
    • Task 2: Participate in a cooperative effort in the overall project to reconstruct the stress field in these seismic zones
      • Deformation pattern and morphology in the Krafla fissure swarm: the Mófell area (work carried out with Dauteuil and Villemin)
      • Tension-shear deformation in the Krafla fissure swarm: the Leirhnjúkur area (work carried out with Dauteuil and Villemin)
  • Subpart 6B: Field and theoretical studies of fault populations
    • Task 1: Make a detailed study of the faults in the TFZ and the SISZ
      • The SISZ
      • The TFZ
      • Effects of fluid pressure on fault development
    • Task 2: Boundary-element models of the faults
      • Analytical and numerical studies on fault populations
    • Task 3: Boundary-element studies of the TFZ and the SISZ
    • Task 4: Make analog models of the SISZ and the TFZ
    • Task 5: Detailed tectonic map of the TFZ
      • The TFZ
• Subproject 7: Theoretical analysis of faulting and earthquake processes
  • Subpart 7A: Crust-mantle rheology in Iceland and Mid-Atlantic Ridge from studies of post-seismic rebound
    • Task 1: Inferences on the regional stress field from the study of secondary earthquake fractures
    • Task 2: Global post-seismic rebound following strike-slip and normal faulting earthquakes
    • Task 3: Comparison between global earth models, including sphericity and self-gravitation, and plane models
    • Task 4: Modelling of a spreading ridge
    • Task 5: Modelling of accelerated plate tectonics on a ridge following a major earthquake in a transform shear zone: inferences on the rheological structure below Iceland
    • PRENLAB workshops and coordination meetings
  • Subpart 7B: Modelling of the earthquake related space-time behaviour of the stress field in the fault system of southern Iceland
    • Task 1: Calculation of the stress field due to motions on the main faults
    • Task 2: Comparison with the seismic moment release
    • Task 3: Stress build-up by these motions and stress release by the major earthquakes
    • Task 4: Forward modelling of the rheological parameters of the lithosphere/asthenosphere in southern Iceland using data of postseismic deformations
    • Methods
    • Modelling tools
    • Report
      • The model on stress changes in the SISZ
      • Model on the influence of volcanic loads
    • Meetings and conferences