Standards for Global Geophysics and Resource Exploration?
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StandardsStandards andand softwaresoftware forfor globalglobal geophysicsgeophysics DietmarDietmar MMüüllerller School of Geosciences and Univ. of Sydney Institute of Marine Science The University of Sydney Why do we need standards for global geophysics and resource exploration? Earth Science is data rich and information poor Earth resources form over time periods of hundreds of millions or billions of years In order to associate a likelihood of resource formation with a particular basin or geological terrane, we must be able to trace all relevant data through geological time PLATEPLATE TECTONICSTECTONICS Most of us have a “static” view of the Earth and nearly all geodata we store in Geographic Information Systems (GIS) are associated with present-day coordinates only. However, the most fundamental, large-scale process occurring in the Earth’s interior is convection of the mantle, responsible for the continual reshaping of the surface through plate tectonics ’Everything’ on Earth is controlled by Plate Tectonics Resources (hydrocarbons, minerals) Geothermal energy (mostly granites and active volcanism) Tourism (landscape, beaches, ocean) Climate past and present (distribution of continents and oceans) Agriculture (limestone, weathered basalt) Wine & beer (beer: magnesium limestone, terroir) Civil engineering (stability of slopes, tunnels, dams, hazards) Evolution of life and biodiversity (distribution of continents) Very important in planetary research Why do we need standards for global geophysics and resource exploration? It is not the data themselves that lead to commercial success, but the well-informed interpretation of geodata in a plate tectonic context, leading to the generation of new ideas, models and more successful exploration We need standardised, platform-independent, web- extensible software and a "Plate Tectonic GIS" in which all data are attached to moving tectonic plates through geological time This software and database system needs to be connected to HPC computing tools for 4D process modelling Data to plate encoder via EarthBytesEarthBytes SystemSystem global plate polygon file to GPML, based on XMML Plate Tectonic GIS Interactive QuickTime™ and a Cinepak decompressor are needed to see this picture. manipulation of plate models GPlates map making module Geodynamic/ (based on GMT software), paleoclimate interactive or scripting-based modelling applications QuickTime™ and a Video decompressor are needed to see this picture. Müller, 2003, Marine geo-informatics, In: The Science Foundation for Physics 60 50 40 30 20 10 Mantle convection 170Ma to present - density anomaly slice at 790 km QuickTime™ and a Video decompressor are needed to see this picture. Mantle convection through time from analytical flow model Starting point: mantle tomographic model 1300km 2700km • Convert velocity anomalies into density anomalies using empirical conversion factor • Use spectral code to advect density anomalies back through time, by spherical harmonic expansion of the flow field • Viscosity model based on geoid/postglacial rebound constraints • Surface plate velocities (and plate boundaries) through time are used as model boundary conditions. Basal boundary free slip. O’Neill, Müller and Steinberger, EPSL 2004, Geochemistry, QuickTime™ and a Video decompressor Geophysics, are needed to see this picture. Geosystems, 2005 Dynamic surface topography due to QuickTime™ and a vertical component Video decompressor are needed to see this picture. of mantle convection Anomalous Late Tertiary subsidence along northern margin of South China Sea (Xie, Müller et al, Basin Research, in rev.) Modelling continental paleostress: Need to merge oceanic and continental data as boundary condition constraints for FEM Collision HY C SA olli PNG sion BA NH JT SOL TK NZ MOR AAD HOT! Plate driving forces 56 Ma Crustal Age (Ma) Rheological Provinces Fold Belts Sedimentary Basins Strength: Cratons > Basins > Fold Belts Cratons N.W. C.S = north west continental shelf, S. C.S. = southern continental shelf, E. C.S. = eastern continental shelf, NEB = north east block, ARB = Arunta block, MIB = Mt Isa Block, MUB = Musgrave block, YB = Yilgarn craton, GB = Gawler block, MD = Murray- Darling basin, N. LA. F. B = north Lachlan fold belt, S. LA. F. B = south Lachlan fold belt, OB = Otway basin, CWZ = Central Weak Zone Late Miocene (20 Ma) Present Early Miocene (45 Ma) Eocene (55 Ma) Dyksterhuis and Müller (Exploration Geophysics, 2004) Dyksterhuis, Albert, Müller (Comp. & Geosci, 2005) Dyksterhuis, Müller, Albert (JGR, in press) Basin dynamics Integration of data as constraints for geodynamic and basin models 2-D (+3d) dynamic basin modelling including the mantle, lithosphere and sediments Investigate alternative basin formation scenarios to provide a framework for new exploration models/plays – Extension/strain history and tectonic reactivation, role of magmatism – resulting paleogeography and basin architecture that controls spatial and temporal hydrocarbon distribution Iberian seismic data Newfoundland seismic data Conceptual Newfoundland -Iberian rifting models Rheic ocean closure Global Crustal Types Continental Crust Oceanic Crust Accretionary Crust Young Accreted Oceanic Terranes Arcs & Rifted Crust Oceanic Plateaus 3-layer model with quartzite rheology for the upper crust, felsic granulite for the lower crust and dry periodotite for the mantle). All layers are 15km thick. One pre-existing fault Is implemented in middle of model, dipping to the right at 45 deg. QuickTime™ and a GIF decompressor are needed to see this picture. Moho temp. of 500 deg. C. QuickTime™ and a GIF decompressor are needed to see this picture. Moho temp. of 600 deg. C. Melt in plume rising beneath thick cratonic keel - with diamonds QuickTime™ and a GIF decompressor are needed to see this picture. O’Neill et al., GSA Spec. Pub. 22, 2003 Temperature isosurface (red), chemically distinct root (orange), diamond stability field (blue diamonds), melt (ie. supersolidus temperature, yellow spheres), and gridded plot of diamonds + melt (bluish grid on top: diamonds and melt simultaneously occur in hot regions). Geodynamic modelling on explorers’ desktops: Exploration geodynamics through interoperability in geo-databases and software Geodynamics Seismic and well Combined mantle convection data integration and and plate kinematic modelling interpretation Palaeostress modelling Lithologies Physical properties Dynamic basin modelling Biostratigraphy (mantle convection, lithos- Basin geometry pheric thinning, sedimentation/ Faulting through time erosion) Frontier basin history Improved palaeogeography based on moving hotspot reference frame Put constraints on tectonic/thermal history of deep sedimentary sections Determine cause of syn-rift magmatism Constrain timing of fault reactivation by combining palaeo-stress modelling with observations from seismic data EarthBytes challenges Standard information model development – GPlates Markup Language - GPML, based on XMML - is still in its infancy (GPlates Group) – GeoDynamics Markup Language - GDML (will probably be spearheaded through Computational Infrastructure for Geodynamics (CIG) Group (GDML) - only a concept for now – Geological timescale model (S. Cox, CHRONOS) - relatively advanced (S. Cox) – Rock properties data base (pmdCRC?) ?? EarthBytes challenges Embedding of gridded data into GPML - based on CSML? (collaboration with AUKEGGS/NERC Data Grid) Platform independent binary encodings essential (netcdf?) Vertical slices as important as in CSML (eg seismic data) Irregularly spaced grids (important for numerical model meshes - also for deforming grids (as tectonics plates are deformable) Design and “populate” data bases (import legacy data) Link variety of geodynamic modelling tools to Earthbytes data EarthBytesEarthBytes PartnersPartners QuickTime™ and a TIFF (LZW) decompressor are needed to see this picture..