Transcript NEAREST_WP02_Valenti - Integrated observations from NEAR

NEAREST Kick Off Meeting
Bologna, 09/10/2006
WP2
Tsunami source
characterisation
OBJECTIVES
Collect wide-angle seismic profiles across the continental
margin and basins offshore SW Iberia to obtain 2-D
velocity models and constrain the geometry of the main
boundaries. Integration of existing MCS depth images and
WAS velocity models must allow to:
1) Map the deep crustal and upper mantle structure, so that
geodynamic models of the area can be tested;
2) Determine the location and crustal-scale geometry of the
main fault surfaces accommodating plate convergence;
3) Construct coarse 3-D velocity models to be used to
relocate local seismicity recorded in WP3;
4) Constrain physical properties (r, f) to characterise the
main structural domains and tectonic features.
TASKS
Task 2.1 Reprocessing and pre-stack depth migration
of existing MCS data
Participating: CSIC/ICREA, ISMAR ,UBO
Task 2.2 Wide-Angle reflection/refraction acquisition
experiment
Participating: CSIC, ISMAR ,UBO, CNRST, INGV, AWI, FFCUL
Task 2.3 Processing and modelling of acquired wideangle seismic data
Participating: CSIC ,UBO, AWI, FFCUL
1 Pre-doc student (36 months)
Task 2.1 Reprocessing and pre-stack depth
migration of existing MCS data
What profiles are worth to be depth-migrated?
are the criteria to select them?
What
Task 2.2 Wide-Angle reflection/refraction
acquisition experiment
CSIC request for ~30 days shiptime with BIO Hesperides (WAS only)
Profile 1: 295 km, Horseshoe
Abyssal plain to accretionary
wedge. To characterize E-W
dipping subduction zone under
the Gibraltar arc
Profile 2: 305 km, Iberian to the
Moroccan margin. To constrain
3-D geometry of plate boundary,
lineament of Portimao-Guadalq.
Banks, nature and variability of
the crust under the prism
Profile 3: 275 km, NE limit of
Gorringe Bank to E Coral Patch
Ridge To characterize deep
structure of Marques de Pombal
and Horseshoe fault system
~25-30 OBS/H each profile > LSF IFMGEOMAR + CSIC, UBO-Ifremer, FFCUL?
Task 2.2 Wide-Angle reflection/refraction
acquisition experiment
Shot over the BB
AWI-OBS network
that will be deployed
as part of WP3:
• Network location
and consequent
airgun shot locations
to be defined
• Ship schedules to
be defined and
coordinated (09/2007
difficult for
Hesperides)
BB AWI-OBS
network location?
Task 2.3 Processing and modelling of acquired
wide-angle seismic data
SUB-TASKS
• Data pre-processing, phase picking
• 2-D refraction/reflection travel-time inversion along
profiles (velocity, reflector’s geometry)
• Estimation of model parameters uncertainty >
Monte-Carlo type
• Construction of a 3-D block using 2-D profiles
• 3-D first arrival inversion at the BB AWI-OBS
network sub-region > to be used joint inversion of
local earthkaques location
WP2 DELIVERABLES
D4 - Reprocessing of existing MCS data
D5 - Cruise for reflection/refraction experiment at sea
D6 - Processing of wide-angle seismic data
WP2 MILESTONES
M2 – End of the processing of reflection/refraction data,
end of experiments at sea
ACTIONS MADE TO DATE
• Proposal for funding and shiptime with Hesperides(?)
submitted to Spanish Agency (Acciones
Complementarias to EU Projects) in July 20th 2006
• Max. Budget is 25% of EU contribution to CSIC
• Response expected by the end of this year
NEAREST-SEIS (WP2)
NEAREST-CORE (WP6)
29 days shiptime
21 days shiptime
Dates: 09/2007 – 09/2008
Dates: 09/2007 – 09/2008
MCS + WAS + Multibeam
+ Potential fields
Coring + HRS + Multibeam
+ Heat flux
NEAREST-SEIS
• 7 days MCS
• 20 days WAS
Port call in
Cadiz between
the 2 legs
PROPOSED SCHEDULE AND
POTENTIAL ISSUES
WP2 Objectives & Tasks
Accomplishment
Pre-doc (asap!)
MCS > OK
WAS? > Survey!
Approval (12/2006)
OBS/H
Hespérides > not
before 11/2008!
Available shiptime slot?
Sarmiento de Gamboa >
operative by 01/2008(?)
LSF-GEOMAR once
shiptime allocated
CSIC funding for 10-15
requested in 08/2006
Other
OBS?