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GeoSciML- a geoscience specific GML application to support interchange of geoscience information. CGI Interoperability Working Group Presented by Stephen Richard Arizona Geological Survey/ U.S. Geological Survey. Objectives of presentation:. What is GeoSciML? How was it developed?
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GeoSciML-a geoscience specific GML application to support interchange of geoscience information CGI Interoperability Working Group Presented by Stephen Richard Arizona Geological Survey/U.S. Geological Survey
Objectives of presentation: • What is GeoSciML? • How was it developed? • What does it look like? • How do I use it?
What is GeoSciML • GeoSciML is an XML-based Geography Markup Language (GML) application • Based on Open Geospatial Consortium (OGC) standards • Framework for application-neutral encoding of geoscience thematic data and related spatial data.
History • Meeting in Edinburgh, Nov. 2003 to discuss problem: • Requirement to provide and exchange data in electronic format • Data from each source in a different format so difficult to integrate • Representatives of geological surveys from: UK, Canada, US, France, Germany, Netherlands, Australia (CSIRO), Sweden, Japan, Czech Republic, Poland, Ireland, Finland • Set up Interoperability Working Group under auspices of new IUGS CGI to address problem
Objectives for working group • Develop a conceptual geoscience data model • Map this to an interchange format • Develop testbed(s) to prove / demonstrate use of the interchange format • Assess vocabulary requirements
Approach: • Draw on previous work • Existing geoscience data models • Existing markup language specs • Face-to-face meetings and Twiki • Start with main components of geological map and borehole data (geological unit, Earth material, faults, contacts, and their defining concepts) • Expand later to other geoscience domains (extend model or import namespaces?) Mostly piggyback on ongoing activities
Participants • GeoSciML development team: • Eric Boisvert (GSC) • Boyan Brodaric (GSC) • Tim Duffy (BGS) • Simon Cox (CSIRO) • Bruce Johnson (USGS) • John Laxton (BGS) • Steve Richard (AZGS-USGS) • Jean-Jacques Serrano (BRGM) • Bruce Simons (GSV) • Lars Stolen (SGU) • Leslie Wyborn (GA)
Process • Review existing models • Develop a conceptual data model and from this derive logical data model in UML • Map this to XML for interchange using OGC GML standard (UML2GML profile) • Use web services for delivery
NADM C1: North American Geologic Map Data Model • Conceptual—UML diagrams and text; implementation not specified • Scope: • Materials—rock, mineral, sediment • Bodies of material (geologic units) • Structures • Processes, Events • Relationships
XMMLObservation and Measurement • OGC draft standard (OGC® 05-087r4) • Scope: • Site (includes boreholes) • Sample • Observation • Measurement • Basis for documenting provenance of data
G S C wrapper GSC GSC GSC sc h e m a W e b U S G S wrapper NGMDB U U SGS SGS C l ien t sc h e m a wrapper S ervice s B G S wrapper B B B GS GS GS sc h e m a G A wrapper G G G A A A sc h e m a Interoperability via web service Communication between service providers and clients takes place using XML mark up. Use of standard markup language means schema mapping only needs to be done once Web service only implements interface for standard markup input and output
Transform Data Interchange Extract Load Interchange schema GeoSciML GeoSciML NGMDB U U SGS SGS GSC GSC GSC wrapper wrapper Data Interchange Each data provider and consumer implements a wrapper that maps xml to and from local schema to interchange schema; Use of standard means this schema mapping only needs to be done once. Users must still resolve semantic (terminological) differences in datasets that do not use a common vocabulary.
GeoSciML v2 • Document content—collection of: • Geologic unit • Geologic structure • Mapped feature (lines, polygons) • Earth material description (rock, unconsolidated) • Vocabulary (Collection of terms with definitions) • Events • Relationships
Geologic Unit • Classifier– link to lexicon, identifies described unit • Body morphology– shape of unit as 3-D body • Color— color of unit in exposures • Composition category– general composition character of unit; chemical or petrographic • Outcrop character — nature of outcrops formed by geologic unit • Parts – aggregate geologic units • Composition -- lithologic constituents • Metamorphic description — facies, grade, peak P, Peak T, protolith • Unit thickness • Age, geologic history — one or more genetic events in history of unit • Bedding character — pattern, style, thickness • Physical properties — density, magnetic susceptibility, porosity, permeability • Weathering character — degree, products, process, environment • Related geologic units and structures – soft typed relationships
Geologic structure • Subtypes: • Shear displacement structure, fault, ductile shear zone • Fracture, joint • Contact – boundary between units • Fold, Fold system – collection of related folds • Foliation, layering • Lineation • Non directed structure – soft typed class to represent sedimentary and igneous structures
Faults • Displacement-- collection of displacement events • Each has age, process environment, movement type (strike slip, normal…) and sense (normal, right…), may have slip or separation • Segmentation, aggregation segments faults Fault system
Structure orientation • Planar and linear orientation elements • Allow numeric measurement, numeric range, or qualitative text specifier (e.g. steep, northerly) • Planar orientation has polarity (facing) • Linear orientation may be directed
Earth Material • Mass noun, not a feature • Subtypes: • Mineral • Inorganic fluid (water..) • OrganicMaterial • CompoundMaterial — material that is an aggregation of constituent parts • Rock, • UnconsolidatedMaterial • MaterialFossil
Rock, Unconsolidated material parts • Each part: • role, proportion, type • represents aggregation of particles of some type, which may have a grain size and shape description • composed of some Earth Material • Relationships between parts (overgrows, replaces…)
Rock, Unconsolidated material properties • Color • Composition category – terms for chemical or petrographic character • Genetic category – term to characterize geologic history of material • Consolidation degree • Lithology classifier – kind of material described, from controlled vocabulary • Physical properties — density, magnetic susceptibility, porosity, permeability • Metamorphic description – facies, grade, peak P, peak T, protolith • Fabric description – type, text description • Particle geometry – grain size, sorting, shape, aspect ratio
Cobre Ridge Tuff (Jurassic)- Drewes [1997] divided into upper and lower welded tuff (units Juw and Jlw of Drewes, 1997) separated by sandstone of Arivaca (Jsa). Described as porphyritic rock with 10-25 % phenocrysts 2-7 mm in size, in cryptocrystalline groundmass with some relict devitrified glass and shards. Phenocrysts included quartz (3-8%), albitized plagioclase (2-10%), potassium feldspar (possibly sanidine in some rocks) (2-10%), biotite (1-5%), and trace magnetite, apatite, and zircon. Lithic fragments and fiamme are sparse. Rock weathers slightly platy, with foliation oriented parallelt o bedding in sandstone of Arivaca. Fiamme and shardy structure are usually visible without a microscope, but in some rocks they are nebulous features. Probably more than 500 m thick.
Metadata • Uses ISO 19115 • Feature Level or Dataset level • Extensive capability to record • Data processing steps • Source citation • Spatial reference • Maintenance information • Use constraints, availability, point of contact….
Linked packages • Observation and measurement • Detailed data acquisition metadata, process, equipment, observation conditions • Sampling • Site, Borehole • Specimen • Assay data exchange • Specimen splits • Chain of custody • Geologic Time • GSSP • Time ordinal era
What is “an Observation” • Observation -- a procedure applied at a specific time and place • Result -- an estimate of some property value • Observed property is bound to a feature of interest
Observed property • Sensible phenomenon or property-type • Length, mass, temperature, shape • location, event-time • colour, chemical concentration • count/frequency, presence • species or kind • Expressed using a reference system or scale • Scale may also be ordinal or categorical • May require a complex structure • “Sensible”, but not necessarily physical …
Feature-of-interest • The observed property is associated with something • “Location” does not have properties, the thing at a location does • The property must be logically consistent with the domain feature-type • E.g. rock sample->density, pixel->colour, city-> population, ocean-surface->temperature • … Observation-target
Procedures • Instruments & Sensors • Respond to a stimulus from local physics or chemistry • Intention may concern local or remote source (brunton compass vs. camera) • Sample (feature of interest) may be in situ or re-located • Observers, algorithms, simulations, processing chains … • “estimation” process
A common pattern: the observation model • An Observation is an Event whose result is an estimate of the value of some observedProperty of the featureOfInterest, obtained using a specified procedure • The Feature-of-interest concept reconciles remote and in-situ observations
Proximate vs. Ultimate Feature-of-Interest • The proximate feature-of-interest may sample a more meaningful domain-feature • Rock-specimen samples an ore-body • Well samples an aquifer • Sounding samples an ocean/atmosphere column • Cross-section samples a rock-unit • Scene samples the earth’s surface • i.e. two feature types involved, with an association between them
GeoSciML use cases • Data publication/interchange • Geologic maps • Borehole geology • Specimen descriptions • Earth material substrate for soil map • Input/output format for applications • 3-D models • Mineral resource assessment • Hazard assessment • Shared schema for specifying properties of interest • Queries • Data discovery • Symbolization
What GeoSciML does not do • Create information • Determine fitness for use • Resolve semantic conflicts • Not efficient for online display of maps • Record cartographic portrayal information
Interoperability Stack interoperability Data content Ontology (shared concepts) Data structure GeoSciML Geoscience OpenGIS Data language GML, XML Communication protocols WFS, WMS, WCS TCP/IP, hardware protocols, etc
SAME? SAME? Semantic interoperability:
Activities: Testbed 2 Use cases • display map, query one feature, return attributes in GeoSciML • query several map features, return GeoSciML file for download • reclassify map features based on GeoSciML GeologicAge or Lithology
Results • Use-case 1: query feature • Query one map feature (e.g. a geologic unit) and return GeoSciML
Current activities • Concept definition task group mission • Specify concept space for GeoSciML attributes • Define categories that cover each space and assign language independent identifiers to each category • Melbourne, Australia Sept. 2007 – test bed 3 use cases Learn more, get involved: https://www.seegrid.csiro.au/twiki/bin/view/CGIModel/GeoSciML or Google ‘GeoSciML Twiki’
Concept Definition Task Group • Specify concepts and property values required to populate GeoSciML document instances • Language independent identifiers allow association of these with different words for different communities
In Closing • Significant challenges • Service definitions • Development of wrappers for mapping to/from interchange format(s) • Semantic interoperability-- shared vocabulary/ontology or software semantic mediation
Why GeoSciML?Geoinformatics! • Discover information resources • Utilize existing data • Enable automated workflow utilizing geoscience information • Decision making; Research; Education
C l ien t Automated process Human user C l ient side m a y be an automated app l ication f or f urther p r ocessing or Query construction, Query construction, a human in f ormation use r . C l ients R esu l t viewin g R esu l t viewin g ope r ate in local e n vi r onmen t Middle w a r e A web service m a y be c l ient f or one or mo r e other services . W eb services W eb services use XML f or communication (syntactic inte r ope r ab il i t y), but each c l ient and data sou r ce m a y use d i f f e r ent schema . Data Tier Data sou r ces a r e hete r ogeneous in schema and semantics Data sou r ces a r e independently managed
Requirements to set up service: • Data in vector digital form • Web server connected to the internet • Internet map server that can access data. • Software to process OGC Web Map Service (WMS) and Web Feature Service (WFS) requests • Software to convert hosted data into GeoSciML based on service requests.
Related Work • CML – components for geochemistry • Water ML – components for hydrogeology • Mineral Occurrence model – components for economic geology • DIGGS – Data interchange for geotechnical and geoenvironmental specialists
feature of interest Feature-type taken from a domain-model observed property Member of feature-of-interest-type procedure Suitable for property-type Application to a domain