COmoros & maYotte : vOlcanism, TEctonics and Seismicity

Outils pour utilisateurs

Outils du site

wp1:start

Différences

Ci-dessous, les différences entre deux révisions de la page.

Lien vers cette vue comparative

Les deux révisions précédentesRévision précédente
Prochaine révision		Révision précédente
wp1:start [2020/03/11 16:07] – i.thinon_brgm.frwp1:start [2024/11/11 15:31] (Version actuelle) – i.thinon_brgm.fr
Ligne 1: Ligne 1:
 =======WP1-Current seismic sequence, deformation and kinematics======= =======WP1-Current seismic sequence, deformation and kinematics=======
-leader: Nathalie Feuillet (IPGP) +Leader: Nathalie Feuillet (IPGP) & Anne Lemoine (BRGM) 
-Participants & coll.: D. Bertil (BRGM), C. Doubre (IPGS/EOST), P. Briole (ENS), A. Lemoine (BRGM), J. Van der Woerd (IPGS/EOST), A. Maggi (IPGS/EOST), C. Satriano (IPGP), P. Bernard (IPGP), W. Crawford (IPGP). J. Battaglia (Clermont-Ferrand U.), A. Lemarchand (IPGP), M. Grunberg (IPGS/EOST), M. De Michele (BRGM), I. Thinon (BRGM), F. Paquet (BRGM), E. Jacques (IPGP).+ 
 +Participants & coll.: D. Bertil (BRGM), C. Doubre (IPGS/EOST), P. Briole (ENS), A. Lemoine (BRGM), J. Van der Woerd (IPGS/EOST), J. Battaglia (Clermont-Ferrand U.), I. Thinon (BRGM), F. Paquet (BRGM), E. Jacques (IPGP), L. Scholtés (Clermont-Ferrand U.), P. Boymond (IPGP) et al.
 ---- ----
 The objectives of this workpackage are to understand the origin of the current seismo-volcanic sequence (magmatic or tectonic origin and possible volcano-tectonic interactions) and to propose a present-day kinematic model at the regional scale and at the scale of the Comoros axis. \\ The objectives of this workpackage are to understand the origin of the current seismo-volcanic sequence (magmatic or tectonic origin and possible volcano-tectonic interactions) and to propose a present-day kinematic model at the regional scale and at the scale of the Comoros axis. \\
Ligne 7: Ligne 8:
 {{:wp1:diapositive4.jpg?nolink&600|}}\\ {{:wp1:diapositive4.jpg?nolink&600|}}\\
 \\ \\
- ** * Task 1.1: Analysis of the current Mayotte Seismic Sequence (MSS) (Leader: D. Bertil)**+ ** * Task 1.1: Analysis of the current Mayotte Seismic Sequence (MSS)**
  
 The main objective of this task is to understand the origin and the dynamics of the MSS, in relation with the tectonic and volcanic structures of the area and with the geodetic observations. The seismic datasets acquired before (ex: RHUM-RUM project) and during the MSS will be analyzed. The study will be primarily conducted in the framework of a PhD thesis (PhD0, BRGM/IPGS co-funding, not included in this proposal). The main objective of this task is to understand the origin and the dynamics of the MSS, in relation with the tectonic and volcanic structures of the area and with the geodetic observations. The seismic datasets acquired before (ex: RHUM-RUM project) and during the MSS will be analyzed. The study will be primarily conducted in the framework of a PhD thesis (PhD0, BRGM/IPGS co-funding, not included in this proposal).
Ligne 14: Ligne 15:
 Finally, all the detection methods described above will be used on data preceding the start of the MSS (May 2018) to check whether MSS was anticipated by precursor activity.\\ Finally, all the detection methods described above will be used on data preceding the start of the MSS (May 2018) to check whether MSS was anticipated by precursor activity.\\
  
-  * **Task 1.2: Active Deformation (Leader: P. Briole) **+  * **Task 1.2: Active Deformation **
 The use of seismic data to quantify the co- and post-seismic and/or dyking deformation will be completed by the surface displacements on Mayotte, using spatial geodetic techniques (GNSS permanent and temporary network and InSAR observations). Offshore, the ground displacement field will be estimated from differential bathymetry method using BATHYMAY data (2004) versus the new data acquired during the MAYOBS cruise (INSU/Tellus). The location and the size of the active structures will be constrained by the observations of the seafloor during MAYOBS, such as submarine flank morphology, evidence of volcanic activity on the seafloor or within the sediment cover. The use of seismic data to quantify the co- and post-seismic and/or dyking deformation will be completed by the surface displacements on Mayotte, using spatial geodetic techniques (GNSS permanent and temporary network and InSAR observations). Offshore, the ground displacement field will be estimated from differential bathymetry method using BATHYMAY data (2004) versus the new data acquired during the MAYOBS cruise (INSU/Tellus). The location and the size of the active structures will be constrained by the observations of the seafloor during MAYOBS, such as submarine flank morphology, evidence of volcanic activity on the seafloor or within the sediment cover.
 All these data and observations will be integrated into mechanical models to constrain the depth and size of the source(s) and its evolution over time, together with the estimate of the volume of magma involved over the whole MSS (e.g. Grandin et al., 2009, Lemoine et al., subm.). \\ All these data and observations will be integrated into mechanical models to constrain the depth and size of the source(s) and its evolution over time, together with the estimate of the volume of magma involved over the whole MSS (e.g. Grandin et al., 2009, Lemoine et al., subm.). \\
  
-  * **Task 1.3: Local and Regional Recent Kinematics (Leader: C. Doubre)**+  * **Task 1.3: Local and Regional Recent Kinematics **
 The main product of this study will be a compilation of active structures (faults, volcanism,…) at the regional scale and at the MSS scale. This compilation will come from those documented in the literature and from the interpretations based on recent bathymetric and seismic data (BATHYMAY, MAYOBS, SISMAORE, SISMAYOTTE). This new tectonic map will be used to compare the distribution and kinematics of active structures with the seismicity distribution and focal mechanisms. These works will provide a basis to evaluate whether the Comoros volcanism is spatially related to the distribution and development of the active faults in the same area. We will focus on the relationships between volcanism and major regional faults.  The main product of this study will be a compilation of active structures (faults, volcanism,…) at the regional scale and at the MSS scale. This compilation will come from those documented in the literature and from the interpretations based on recent bathymetric and seismic data (BATHYMAY, MAYOBS, SISMAORE, SISMAYOTTE). This new tectonic map will be used to compare the distribution and kinematics of active structures with the seismicity distribution and focal mechanisms. These works will provide a basis to evaluate whether the Comoros volcanism is spatially related to the distribution and development of the active faults in the same area. We will focus on the relationships between volcanism and major regional faults. 
 \\ \\
 Together with the worldwide and Africa-Indian Ocean regional networks, the new GNSS data will allow us to build a regional present-day, plate tectonic, kinematic model in order to better understand kinematics of the southern termination of the East-African Rift, its relation with the Indian Ocean Ridge and other structures, such as the Davie Ridge etc…, and focusing on the kinematic nature (divergent vs. transform plate incipient boundary?) and role of the Comoros archipelago axis in the regional geodynamics.  Together with the worldwide and Africa-Indian Ocean regional networks, the new GNSS data will allow us to build a regional present-day, plate tectonic, kinematic model in order to better understand kinematics of the southern termination of the East-African Rift, its relation with the Indian Ocean Ridge and other structures, such as the Davie Ridge etc…, and focusing on the kinematic nature (divergent vs. transform plate incipient boundary?) and role of the Comoros archipelago axis in the regional geodynamics. 
  
wp1/start.1583939248.txt.gz · Dernière modification : de i.thinon_brgm.fr
Donate Powered by PHP Valid HTML5 Valid CSS Driven by DokuWiki