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NADM , Links, GeoMatter and friends
An overview of NADM Eric Boisvert & Vincent Desjardins
Centre géoscientifique de Québec
Schedule
What is NADM ?
What is <geo>Link (Cordlink, Hydrolink, GASLLink,etc...)
What is GeoMatter ?
How does it work ?
A down to earth example
NADM North American Data Model
Result of an international effort (USA and Canada, Mexico could eventually jump in)Lead by a « Steering Commitee » composed of USGS, AASG, GSC and OGS.SC created a set of 6 Technical Teams addressing specific issues of the Data Model
Requirements Data Model Design Documentation Data Interchange Science Language Tool Development
NADM North American Data Model
GSC has 2 seats, 1 occupied by Boyan Brodaric and 1 rotating seat.Provincial also have 2 seats, one occupied by Brian Berdusco (OGS) and another to be filled (Eric Grunsky, Alb. ?)Remaining seats occupied by USGS and AASG (American Association of State Geologists)
NADM North American Data Model
They produced several documents but the most important for us so far is the Version 4.3 of the database structure.http://geology.usgs.gov/dm/model/Model43a.pdf
This is the only true NADM data structureA NADM inspired version has been developed for the Cordlink ResSources project. It is called V 5.2 or simply the « Cordlink version »http://cordlink.gsc.nrcan.gc.ca/cordlink1/info_pages/English/dm52.pdf
NADM 4.3 versus 5.2 at a glance
5.2 is a generalization of 4.35.2 is enhanced to serve as a Virtual Library core (handles images and texts)5.2 has « shared attributes »5.2 embeds higher level of information description and relationships5.2 embeds tool specific metadata (system tables)
NADM logic (5.2)
Source
Legend schemeLegend
items
Spatial objects
references
Compound
Object
Archive
Singular
Object
Archive
Attributes
NADM logic (5.2)
Source: Map related information- Author, Edition, Publication, etc.- Scale, projection, resolution
Legend : Scheme and Classification-Labels, symbolisation, Legend description
Spatial References: Geographical objects- References to points, lines, polygons, volumes, etc..
COA, SOA, Attributes: actual data-Rock description, structural measurements, sample descriptions, ages, stratigraphic positions
Glossary SourceScheme
Glossary Classification ObjectSymbol
Glossary Spatial objects
Glossary
striae
Classification
Scheme
SOA:
Type: striae
Azimuth: 210
Direction: Unknown
Chronology: 1
•Glacial flow indicator
•Striae
Faint marks on rock
Except on volcanic outcrops
Why is it so interesting ?
Data deep : it incorporates both factual and interpretative information
v 5.2 integrates images and texts
Incorporates « conceptual » integration through COA hierarchy
Say what ?
Incorporates « conceptual » integration through COA hierarchy
Universe
Atmosphere
Lithosphere
Hydrosphere
Biosphere
Continental
Oceanic
Plateform
Sea floor
COA
Most difficult concept to understand
It’s a hierarchical list of « things » that will appear on a map
There is a fuzzy frontier between COA and legend
COA
Saint Lawrence LowlandPotsdam Group
• Cairnside Formation
• …
Chazy Group
IgneousPlutonic
• Mafic Gabbro …
• Intermediate …
• Felsic Syenite Granite …
Volcanic• Mafic
ContinentalAlluvial
• Alluvial terrasses
• …
Glacial
Lithostratigraphic
Morphogenetic
Lithologic
COA
NADM allow multiple types of COA arborescences to coexists
UniverseRock Unit
• …
MorphoGenetic• ...
Rock Unit
specific attribute
table
Morphogenetic
specific attribute
table
COA
COA
Emphasize the fact that a map is always create with a conceptual frameworkGeologists are not interoperable between themselves (specially if you include time factor) (D. Lebel, March 21, 2000)
So this is not a limitation of NADM itself
Geologists were
not using the same COA
tree
Interoperability & integration
A B
A1 A2 B1
Corporate wide concepts
Local
Why do I annoy you with this COA tree stuff ?
Example of different concept levels
Corporate levelTholeiite
Local LevelHigh Mg Tholeiite with large amount of feldspar phenocrists.
Someone working in volcanic petrology could
have 24 differents classes of Tholeiites, but unless the client
is looking something very specific, chances are he would stop
at the tholeiite level
Interoperability
A B
A1 A2 B1
A B
A1 B2 B1
Ba Bb BcSite 1 Site 2
Do you have any A ?
A1 -> A
A2 -> AA1 -> A
Benefit of the COA approach
Can create a global integration of geosciences « things »
Corporate don ’t have to update the tree everytimes to accomodate new concepts
More specific concepts can be created at local level without affecting the rest
Helps search and retrieval of information in multiple (distributed) databases
NADM Important consideration regarding GIS
NADM data
structure
DatasetID
SpatialObjId
GIS
NADM only handles references to
Spatial objects
DatasetId = Coverage
SpatialObjId = item
NADM Where does it fit ?
NADM structured
System
Cordlink
GeoServ
Spatial Objects pool
NADM Where does it fit ?
NADM structured
System
Spatial Objects pool
ArcView
Shape files, ArcInfo Coverages
DatasetIdSpatialObjId
Cordlink, HydroLink and others
Application that taps into NADM structure to deliver information
5.2 version has been developed to respond to Cordlink needs
Cordlink is built around the « Virtual Library » paradigm
Hydrolink is a « port » of Cordlink to address hydrogeological purposes
Cordlink and Hydrolink
Cordlink, HydroLink and others
NADM structured
System
Spatial Objects pool
SDL and WFM
Browser
MapGuide
Server
ColdFusion
Server
MapGuide
Viewer
.cfm files
HTML
request
DatasetIdSpatialObjId
DatasetIdSpatialObjId
What’s next ?
NADM is getting more and more attention as a data integration approach
Is this truly perfect ???
Nope, there are a couple of flawsSymbolisation has a couple of conceptual problems, for instance, some symbolisation is SOA basedFormally, a single spatial object can be related to more than one COA in the same map (leading to another symbolisation problem)
I personally think symbolisation should have been left out of the model
SOA symbolisation
Gabbro X
COA
Therefore, these blobs are related to this COA by the mean
Of this legend item and given this symbol
Specific attributes of blobs
Are not required
SOA symbolisation
Schistosity
COA
1- Multiple symbol for 1 point
2- Rotation from SOA
3- Dip label also from SOA
45
30
44
SOA
SOA
SOA
Multiple COA
Gabbro X
COA
COAAquitar
WARNING – Personal opinion
Keep the database at the data content level
Implement external symbolisation processes (such as Coleman-Sadd’s GeoLegend) to create map out of database content
This is an open debate
What is Geomatter ?
We have NADM in the core, <geo>link to diffusion information, now how do we populate it ?
GeoMatter is essentially a tool to populate the database
NADM version 5.2 - scary version
Friendly version
GeoMatter philosophy
COA Generalization
Hide data structure complexity
What ’s missing ?
Geomatter
Curly
« scripts »
Entry tools
Cordlink and other
<geo>links
Cubewerks stuff
Diffusion tools
Mostly none
Geomatter (?)
Management tools
None
Import/Export tools
What ’s next ?
servlet
OGDI
Abstraction
layer
NADM
OpenGIS
Java
clientNADM API
OGDI API