DEPARTMENT OF EARTH SCIENCES            UNIVERSITY OF WESTERN ONTARIO


GIS in Geology and Geophysics

COURSE OUTLINE

    A Geographic Information System is a computer-assisted system for the acquisition, storage, analysis (derivative mapping, cartographic and process modeling), and display of spatially referenced data. The system employed in this course is however designed specifically for the geologist/hydrogeologist/geophysicist, and is an extension of the normal methods of analysis of the patterns of geological and geophysical data derived from field mapping and the examination of aerial photos and satellite, gravity, magnetic, and radiometric images.

     While  providing a general introduction to the principles and methodology of Geographic Information Systems as applied to Earth Science, the course will emphasize the practical aspects of setting up a mapping program and establishing a data management system. In as much as the course is largely lab-based, ample  opportunity will be provided for hands-on experimentation with a number of GIS software applications as they might be used in both custodial and project related programs of geological mapping,  mineral potential mapping, resource evaluation, and hazard and environmental assessment.

     Students will first learn the fundamental difference between the raster and vector methods of portraying images, the file structures of the two kinds of images, the concept of paletttes, and the means by which one kind of image can be converted to the other. This will be followed by an examination of coordinate systems, map projections, and the nature of vector images in the form of digital national base maps generated by national and provincial mapping agencies, and how they can be used along with aerial photographs, and existing hard copy geological maps to set up a mapping program. The use of GPS in the electronic determination of coordinate locations will logically lead into the section dealing with the collection and storage of spatial data in various database systems,  the drawing of geological maps, and the concept of topology.  The course will then deal with the raster characteristics of digitized aerial photographs (image enhancement) and remote sensed images, and their use in cartographic modelling and image analysis.

    Software packages used in the course include AUTOCAD MAP (+ FIELDLOG)  and GSMCAD for vector based systems, and IDRISI for raster based systems.  Consideration will also given however to the methodologies employed by ARCVIEW-ARC/INFO and VISION,  and exercises are provided illustrating the portability of spatial data between these various systems.  High-end raster image systems such as PCI and ERMAPPER  will also be demonstrated using Radarsat datasets for the Sudbury region. Please note that the course is not meant to be a general primer in the use of Autocad Map, IDRISI, ArcView, Arc/Info, Vision, PCI or ERMAPPER, and only those components relevant to the Geology/Geophysics theme of the course are treated in detail. No consideration is given to ATLAS, MAPINFO, MICROSTATION, TNT, or INTERGRAPH. Choice of software is largely governed by software cost, and useage of the software by Canadian Federal and Provincial Geological Surveys, the Ontario oil industry, and Canadian mining companies.
(see also Manifold at http://www.manifold.net/news/news_set.html )

    In preparation for the final examination, the concluding part of the course will involve several intensive coaching sessions designed to firmly fix the concepts and terminology used in all forms of data management, data visualization, and visual data analysis.

    Disclaimer: although now two-years old, this course nevertheless remains  very much in the development stage, and is therefore incomplete  in terms of  content,  design,  and pedagogical construction.  The author therefore welcomes constructive suggestions concerning the organisation of the course, and the correction of any errors of  fact,  logic, or syntax.  Please do not be shy!

    This web pages at this site were constructed using Microsoft Word (text), Netscape Composer (tabs, colour, links) , Wordpad (html editing), Microsoft PhotoEditor and Microsoft PhotoDraw (graphics).

    List of Lecture Modules
 
01 The nature of Vector and Raster images and files and their mutual conversion
02 Map Projections
03 Ontario Data Base Maps
04  The Canadian NTDB Maps
05 Digital Line Graphs
06 The digital line graph spatial data transfer standard
07 Using the Global Positioning system
08 Georegistration
09 Georegistration using Autocad Map
10 Data Models
11 Fieldlog in DOS
12 Fieldlog and Autocap Map- the Snow Lake Database
13 Setting up Fieldlog and importing data
14 GSMCAD
15 Drawing in Autocad Map
16 External Attribute databases
17 Topology and Map Analysis
18 Aerial Photographs
19 Cartographic Modelling
20 Remote Sensing
21 Macros and Scripts
22 Linking external databases in Idrisi
23 Acessing the Digital Geological Map of Canada
24 Arc/Info-ArcView to Autocad Map
25 Arcview 3.2
26 DXF files and Idrisi
27 Interpolation
28 TIN
29 Raster File Format Conversion
30 Albero
31 Visual Basic/ActiveX - Inovagis
32 RADARSAT
33 High end software
34 Links to Remote Sensing Web Courses


VECTOR versus RASTER IMAGES


GIS data sources; spatial frame elements and attributes; creating vector, raster, and attribute value files; documentation files; the conversion of vector images to raster images.
FILES: c:\aacrse\505\idr\useattr\vecras.rtf (1)

CLICK HERE TO GO TO MODULE 1.
TEST YOUR KNOWLEDGE - What do you know about Vector and Raster images?
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VECTOR IMAGES


  DIGITAL BASE MAPS

Map Projections: conversion of latitude-longitude to UTMS
FILES: c:\aacrse\505\ltlg2utm\utms.rtf (12)

CLICK HERE TO GO TO MODULE 2
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       LINKS TO COORDINATE CONVERSION SOFTWARE
   http://mac.usgs.gov/mac/isb/pubs/pubslists/fctsht.html
   http://www.ngs.noaa.gov/PC_PROD/pc_prod.shtml#UTMS
   http://everest.hunter.cuny.edu/mp/software.html
   http://users.skynet.be/tandt/
   http://cousin.de/kkisbin/trafo.tcl
 


Ontario Digital Base Maps - projections, datums, tiles, and thematic layers.
FILES: c:\aacrse\505\odbm\odbm.rtf (5)

CLICK HERE TO GO TO MODULE 3
TEST YOUR KNOWLEDGE - What do you know about ONTARIO DIGITAL BASE MAPS
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The Canadian NTDB and National Topographic Atlas - data specifications.
FILES: c:\aacrse\505\ntdb\ntdb.rtf (4)

CLICK HERE TO GO TO MODULE 4.
TEST YOUR KNOWLEDGE - What do you know about DIGITAL BASE MAPS
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Digital Line graphs (DLG) and Digital Terrain/Elevation Models (DTM/DEM) (demidris).
FILES: IDRISI exercise 16 (6)
SEE IDRISI TUTORIAL

CLICK HERE TO GO TO MODULE 5.
TEST YOUR KNOWLEDGE - What do you know about DLG's and DEM's?
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DLGSDTS, the digital line graph spatial data transfer standard.
FILES: c:\505\NTDB\dlgsdts\sdts-tutorial.pdf (7)
AVAILABLE AS A PDF FILE

CLICK HERE TO GO TO PDF FILE.
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Using GPS for the location of geological ground stations (outcrops/sampling stations): the Almanac and QPLAN; PFINDER: downloading the data dictionary to the data-logger and collecting data; uploading coordinate and attribute data (SSF files) to the PC; base stations and differential correction.
FILES: c:\aacrse\505\gps\gps1.rtf (9)

CLICK HERE TO GO TO MODULE 6.

see Geologic Mapping and Collection of Geologic Structure Data with a GPS
Receiver and a Personal Digital Assistance (PDA) Computer by Gregory J. Walsh1, James E. Reddy, and Thomas R. Armstrong

http://pubs.usgs.gov/openfile/of99-386/walsh.html
TEST YOUR KNOWLEDGE - What do you know about GPS?
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  SETTING UP A COMPUTER-AIDED MAPPING PROGRAM


Georegistration and changing Reference Systems.
FILES: IDRISI Tutorial Exercise 15, 17). (11)
CLICK HERE TO GO TO MODULE 7.
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Using Autocad Map to georegister base maps, geological maps, aerial photographs, satellite images and geophysical data in preparation for a exploration mapping program.
    FILES: no .rtf file

CLICK HERE TO GO TO MODULE 8.
TEST YOUR KNOWLEDGE - What do you know about Georegistration?
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    STORING POINT VECTOR DATA IN A RELATIONAL DATABASE


WHAT IS A DATA MODEL? - grammar, vocabulary and content

 The storage and organization of point source geological attributes using the GSC developed stand-alone software FIELDLOG v. 2.83; importing ascii comma delimited surface or bore hole data files (200a.dat and 200b.dat) into Fieldlog; setting symbol defaults; exporting DXF files and drawing maps with CorelDraw.
FILES: c:\aacrse\505\acad\flogdos.rtf (13)

CLICK HERE TO GO TO MODULE 9.
CLICK HERE TO GO TO FIELDLOG V2.83 EXERCISE.
TEST YOUR KNOWLEDGE - What do you know about relational databases?
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The Fieldlog v. 3.0 interface with Autocad Map; plotting point data; symbol libraries; plotting structural symbols - the Snow Lake database.
FILES: c:\aacrse\505\acad\fltut.rtf (13)

CLICK HERE TO GO TO MODULE 10.
TEST YOUR KNOWLEDGE - What do you know about FIELDLOG?
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Setting up Fieldlog - Ellipsoids, Datums, and the Projection Transformation (USER, LAT/LONGS, UTM) and importing comma delimited data into Fieldlog; creating stereo, rose, and geochemical plots; the NORMIN database.
FILES: c:\aacrse\505\flogv3\imptofl3.rtf (15)

CLICK HERE TO GO TO MODULE 11.
CLICK HERE TO GO TO NOTES ON THE NORMIN DATABASE.
CLICK HERE TO GO TO THE ARCVIEW MODULE.
TEST YOUR KNOWLEDGE - What do you know about IMPORTING DATA INTO FIELDLOG?
Click here to return to lecture list

see also
North American Data Model for Geologic Maps:
    http://geology.usgs.gov/dm/
Digital Mapping Techniques 99
    http://www.uwex.edu/wgnhs/dmt.htm
Digital Mapping Techniques 2000
    http://www.uky.edu/KGS/mapping/mapping.html
CordLink Info
    http://pubs.usgs.gov/openfile/of99-386/brodaric1.html
CordLink Site
   http://132.156.108.208/Cordlink1/
OGS
    http://www.gov.on.ca/MNDM/MINES/OGS/mmdogse.htm
OGS Digital Data
    http://www.gov.on.ca/MNDM/MINES/PUB/digcat/erlis.htm
OGS Operation Treasure Hunt
    http://www.gov.on.ca/MNDM/MINES/oth/index.htm
NGSC Publications for Canada
    http://ntserv.gis.nrcan.gc.ca/


    DRAWING A GEOLOGICAL MAP


GSMCAD - the USGS mapping software.
FILES: c:\505\gsmcad\gsmtut.rtf. (25)

CLICK HERE TO GO TO MODULE 12.
TEST YOUR KNOWLEDGE - What do you know about GSMCAD?
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Drawing a SPAGHETTI MAP in Autocad  -  Autocad functions: drawing and sketching polylines, converting polyline segments to single polylines, and generating polygons in AutoCad with bpoly; layers; modify; change entities; map trimming; digitizing, tablet calibration; raster back-drops.
FILES: c:\aacrse\505\acad\draw.rtf (18)

CLICK HERE TO GO TO MODULE 13a. - Autocad drawing tools
CLICK HERE TO GO TO MODULE 13b. - drawing exercise
CLICK HERE TO GO TO MODULE 13c. - using the tablet
CLICK HERE TO GO ARCVIEW
TEST YOUR KNOWLEDGE - What do you know about DRAWING SPAGHETTI MAPS USING AUTOCAD?
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External attribute databases such as ACCESS and EXCEL - linking map polygons.
FILES: c:\aacrse\505\acad\accessam\accessmap.rtf  (23); c:\aacrse\505\acad\excelam\excel1.rtf (24)

CLICK HERE TO GO TO MODULE 14 - ACCESS.
CLICK HERE TO GO TO MODULE 15 - EXCEL.
TEST YOUR KNOWLEDGE - What do you know about LINKING AUTOCAD DRAWING OBJECTS TO AN EXTERNAL DATABASE?
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 TOPOLOGY AND MAP ANALYSIS IN AUTOCAD

Drawing a TOPOLOGICAL MAP; polygon locators/label points/centroids; buffers; boolean map analysis.
FILES: c:\aacrse\505\acad\topol\topol1.rtf (19)

CLICK HERE TO GO TO MODULE 16.
CLICK HERE TO GO TO MAP ANALYSIS EXERCISE.
TEST YOUR KNOWLEDGE - What do you know about TOPOLOGY
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RASTER IMAGES


    AERIAL PHOTOGRAPHS AS RASTER IMAGES

Aerial photography; scanning and pseudo-colouring; classification; air photo interpretation.
FILES: c:\aacrse\505\idr\aerial.rtf(31)

CLICK HERE TO GO TO MODULE 17.
TEST YOUR KNOWLEDGE - What do you know about pseudocolouring?
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    RELATING DIFFERENT KINDS OF SPATIAL DATA  - CARTOGRAPHIC MODELING

Cartographic modelling and Boolean images (ASSIGN; RECLASS; OVERLAY; GROUP; AREA).
FILES: c:\aacrse\505\idr\ex5\id5geo.rtf  (2)

CLICK HERE TO GO TO MODULE 18.
TEST YOUR KNOWLEDGE - What do you know about CARTOGRAPHIC MODELLING?
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   REMOTE SENSED IMAGES - IMAGE ANALYSIS

Principles of remote sensing - the integration of Landsat TM, radar, and geomagnetic images.
FILES: c:\aacrse\505\remote\remote.rtf (8); satellite and magnetic imagery of the SUDBURY basin.

CLICK HERE TO GO TO MODULE 19.
TEST YOUR KNOWLEDGE - What do you know about REMOTE SENSING?
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Writing macros and scripts.
FILES: c:\aacrse\505\idr\ex9\id9macro.rtf (27)

CLICK HERE TO GO TO MODULE 20.
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    RELATING DATA IN TABULAR FORM TO DATA IN IMAGE FORM

Linking an external database to raster and vector images in IDRISI.
FILES: c:\aacrse\505\idr\ex7id\id78dbs.rtf (3)

CLICK HERE TO GO TO MODULE 21.
CLICK HERE TO GO TO ARCVIEW.
TEST YOUR KNOWLEDGE - What do you know about LINKING RATER IMAGES TO AN EXTERNAL DATABASE?
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   AUTOCAD MAP AND ARC/INFO-ARCVIEW

Digital Geological Map of Canada - ARC/INFO, ARCVIEW viewing software.
FILES: c:\aacrse\505\gscmap\gscmap.rtf, DBSTRUC.rtf (20), FILESDF.rtf (21)
also used in course 300B 'Geological Evolution of North America'.

CLICK HERE TO GO TO MODULE 22.
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ARC/INFO - ARCVIEW to Autocad Map conversion.
FILES: c:\aacrse\505\gscmap\arc2cad.rtf (22)

CLICK HERE TO GO TO MODULE 23.
TEST YOUR KNOWLEDGE - What do you know about ARC/INFO - AUTOCAD MAP CONVERSIONS?
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       ARCVIEW

The basics of ArcView 3.2 and Autocad to ArcView conversion.
    FILES: c:\aacrse\505\arcview\arcview.rtf

CLICK HERE TO GO ARCVIEW NOTES MODULE 24
    see also: http://www.esri.com/software/arcview/whatsnew.html
TEST YOUR KNOWLEDGE - What do you know about ARCVIEW?
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  CONVERTING VECTOR IMAGES AND TABULAR DATA TO  RASTER IMAGES


Conversion of DXF vector polygons to IDRISI raster polyline and polygon images.
FILES: c:\aacrse\505\acad\acad2id3.rtf (26)

CLICK HERE TO GO TO MODULE 25.
TEST YOUR KNOWLEDGE - What do you know about CONVERTING VECTOR OBJECTS TO IDRISI VECTOR OBJECTS?
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Creation of raster point images from X-Y-Z data files, and the INTERPOLATION of trend surfaces.
FILES: c:\aacrse\505\acad\acad2id\acad2id2.rtf (16)

CLICK HERE TO GO TO MODULE 26.
TEST YOUR KNOWLEDGE - What do you know about INTERPOLATION?
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TIN.
FILES: c:\aacrse\505\idr\tin\tin.rtf(30)

CLICK HERE TO GO TO MODULE 27.
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    RASTER FILE FORMAT CONVERSIONS AND IDRISI SOFTWARE EXTENSIONS


File format conversion programs; GXF/ASCII format to IDRISI/ASCII format; change Vision geophysical data (radiometric, magnetic, etc) to IDRISI format.
FILES: c:\aacrse\505\vision\vision.rtf.(32)

CLICK HERE TO GO TO MODULE 28.
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Albero by Michael Bedward.
FILES: c:\aacrse\505\idr\albero.rtf (28)

CLICK HERE TO GO TO MODULE 29.
Available only as an explanatory file written by M. Bedward
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Visual Basic/ActiveX INOVAGIS by Pedro Pereira Gonçalves
FILES: C:\5050\idr\inovagis\info.rtf; (29)

CLICK HERE TO GO TO MODULE 30.
Available as an info file written by Pedro Pereira Gonçalves
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   RADARSAT AND HIGH-END GIS SOFTWARE PACKAGES

Using radar imagery (RADARSAT)
FILES: c:\aacrse\505\radarsat\usguide.pdf (33)

CLICK HERE TO GO TO MODULE 31.
AVAILABLE  AS A .PDF FILE
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High end image systems: PCI, ERMAPPER, TNT, ARCINFO, MapINFO-ENCOM, CARIS, GDM-SynARC, GEMCOM, MAPTEK, SYNMAP (PC), AUTOCAD WORLD, and GRASS (Unix)
FILES: c:\aacrse\505\remote\sources.rtf (34); c:\aacrse\505\remote\pciman.rtf (35); pcidec.rtf (36); c:\aacrse\505\remote\TMIMAGE.rtf (37)

CLICK HERE TO GO TO MODULE 32.
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WEB-BASED COURSES IN REMOTE SENSING

     The NASA WEB course in Remote sensing
        (http://code935.gsfc.nasa.gov/Tutorial/TofC/table.html)

     Canadian Centre for Remote Sensing WEB Tutorial
       (http://www.ccrs.nrcan.gc.ca/ccrs/eduref/tutorial/indexe.html)

     The Murnion ARCINFO web course.
        (http://boris.qub.ac.uk/shane/arc/ARChome.html)

     The Short NASA Web remote sensing course                    (http://www.sbg.ac.at/geo/idrisi/Remote_Sensing_Tutorial/code935.gsfc.nasa.go v/IIFS-html/LT/NewTutorial/intro1.html)

        Click here to return to lecture list

        Free maps and images


       REFERENCE TEXTS:

Avery, T.E. & Berlin, G.L. 1992. Fundamentals of Remote Sensing and Airphoto Interpretation, 5th Ed., MacMillan Pub. Co., 472 p.

Bonham-Carter, G.F. 1994. Geographic information systems for geoscientists. Computer Methods in the Geosciences, v. 13, Pergamon. (principal text)

Drury, S. 1993. Image interpretation in Geology. Chapman and Hall, London.

Eastman, R.J. 1994. IDRISI - manuals. Clark University Graduate School of Geography.

Jensen, J.R. 1995. Introductory Digital Image Processing, a remote sensing perspective, 2nd edition. Prentice Hall Series in Geographic Information Science.

Lillesand, T.M. and Kieffer, R.W. 1993. Remote Sensing and Image Interpretation, 3rd Ed. J. Wiley & Sons, 720 p.

RadarSat International 1997. RADARSAT Geology Handbook.

Sabins, Jr., F.F. 1987. Remote Sensing: Principles and Interpretation. 2nd Ed. W.H. Freeman & Co., 449 p.

     Selected Bibliography, Geology and Mining

Anonymous. Feb. 8, 1993. Geo-haz Consultants. Summary of Procedures to Produce a Landslide Susceptibility Map. p. 1-2.

Anonymous. Sept. 1992. Computers and Mining. Gibbs Associates Vol. 8, no 1.

Anonymous. May 1992. Geographic Analysis Software. Coal magazine. p. 60.

Krist, Frank J., Daniel G. Brown. Sept. 1994. GIS Modeling of Paleo-Indian Period Caribou Migrations and Viewsheds in Northeastern Lower Michigan. PE&RS, Vol. 60, No. 9, p. 1129-1137.

McCalpin, James P. Jan. 1993. The Professional Geologist. Geohazards Mapping and Geographic Information Systems, Vol. 30, No. 1, p. 5-6.

Memmi, John M. Feb. 1995. Expertise and GIS Converge for Diamond Exploration. GIS World, Vol. 8, No. 2, p. 54-55.

Teeuw, Richard M., 1995. Groundwater Exploration Using Remote Sensing and a Low-Cost Geographical Information System. Hydrogeology Journal, Vol. 3, No. 3, p. 21-30.


    Software kindly made available by the Ontario Geological Survey under the Survey's Digital Data Royalty Licence Agreement:

Data Set 6 Bedrock Geology of Ontariobedseam.dxf

Data Set 11Tectonic AssemblagesTecseam.dxf

Data Set 12 Township and Areas of Ontario Lambert Conf.- Ont_lamb.dxf; UTM - Twp_z15,16,17,18.dxf

Data Set 13Drill Hole DatabaseASCII text files

Data Set 22 Topographic Map of OntarioBaseseam.dxf

Data 36 Geological compilation of the Timmins area, Abitibi Greenstone beltUTM NAD1927 1:20,000

ERLIS data set 1009Airborne Mag. and Electromag data for the Wawa area, Dighem III, CENTURION Data Display

    MAP PROJECTION SPECIFICATIONS FOR LAMBERT CONFORMAL - OGS Data set 12

The Township and Areas were digitized from hardcopy 1:50,000 scale NTS maps and assembled into an Ontario-wide fabric in Lambert Conic Conformal map projection. The following parameters define the planimetric reference grid:

Clarke 1866 ellipsoid a=6, 378,206.4 (equatorial radius) e=0.006768658 (eccentricity squared)

Standard parallels 49 degrees N latitude 77 degrees N latitude

Origin 92 degrees W longitude 0 degrees N latitude; Central Meridian 92 degrees W longitude

False Easting 1,000,000 metres


    MAP PROJECTION SPECIFICATIONS FOR LAMBERT CONFORMAL - GSC, Geological Map of Canada

    Lambert Conformal Conical Projection parameters

        Type
                 Lambert Conformal Conic projection
        Datum
                 North American Datum 1927 (NAD27)
        Units
                 metres
        Spheroid
                 Clarke, 1866
        Lambert standard parallels
                 49 00 00 N
                 77 00 00 N
       Projection origin
                 95 00 00 W (central meridian)
                 49 00 00 N
       False origin
                 (easting, northing)=(0, 0)


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            GEOSTATISTICS - GSTAT
        Gstat is a computer program for geostatistical modelling, prediction and simulation, copyright 1992, 1998 (C) Edzer J. Pebesma. The Gstat program is free software and can be redistributed and/or modified under the terms  of the GNU General Public License as published by the Free Software Foundation. Information about the source code and documentation of Gstat are available at: http://www.geog.uu.nl/gstat/

     Idrisi32 provides three interactive interfaces to Gstat functions:

     1. Spatial Dependence Modeller
     2. Model Fitting
     3. Kriging and Simulation

     Exploratory Data Analysis
     In addition to the variogram modelling options in the Spatial Dependence Modeler and Gstat, other Idrisi32 modules have been revised to provide better support for geostatistical analysis. These include interactive displays, histogram analysis (HISTO), moving window statistics (via a new version of the FILTER module), spatial autocorrelation assessment (AUTOCORR), trend analysis (TREND) and scattergram analysis (SCATTER).

    The most fruitful exploratory data analysis is achieved by viewing and describing a data set through a variety of means, and reviewing such representations in light of other ancilliary information known about the sampled phenomenon.

     Spatial Dependence Modeler
 The Spatial Dependence Modeller is an interactive interface that accesses a combination of Clark Labs and Gstat functions for creating h-scatterplots, surface variogram models, directional variogram models, and additional summary statistics. Spatial continuity can be modelled using the following methods: semivariogram (moments estimator or Cressie robust estimator), covariogram, correlogram, cross variogram, cross covariogram, or cross correlogram. Results can be saved and copied to documents. Data transformations allow on-the-fly application of the log transform, standard, and indicator transform.

     Variograms can be omnidirectional or directional. An omnidirectional variogram combines all possible directions (i.e., all sample pairs) in a single variogram. It can be represented as a curve, or it can be extended to create a surface variogram (grid). The figure above shows both the surface and the
directional variograms. The raster grid represents statistical space in which lag distance zero is located in the center and lag distances increase outward in all directions. The attribute of each pixel represents an average of variogram values for the particular distances and directions (i.e. separation vectors) defined by the pixel location. Lag separation distances can be regularly or irregularly spaced. The surface representation may be used to determine the maximum and minimum directions of spatial continuity.

     Model Fitting
 The Model Fitting interface allows for interactive fitting of different mathematical structures to the variogram. Ten structure types are available: spherical, exponential, gaussian, linear with sill, linear, power, logarithmic, circular, pentaspherical, and periodic. The fitting method algorithms accessed in Gstat include Weighted Least Squares, Weighted Least Squares with normalized weights, and Restricted Maximum Likelihood (REML).

     The top graph of the interface reflects the model to be fit and geometric anisotropies (when present), while the lower graph serves as a visual tool for viewing the independent structures. The three independent structures provided can be used for modeling nested structures, including zonal anisotropies.

     Kriging and Simulation

     The Kriging and Simulation interface provides access to simple and ordinary kriging and cokriging, stratified kriging and Gaussian conditional and unconditional simulation (including multiple simulations). It includes data transformation (log and standardization), multiple methods for setting the neighborhood parameters for local kriging interpolation, and cross-validation of the sample data. A mask image can be used to limit regions to be interpolated. In addition, this mask image can identify regions (called strata) to be interpolated separately.

     References:

 “Conditional simulation and the value of information,” In: Geostatistics for the next Century, R. Simitrakopoulos (ed.), Kluwer Academic Publishers, 209-217, 1994, (Solow, A.R. and Ratick, S.J.).

 A Method for Incorporating Topographic Uncertainty in the Management of Flood Effects Associated with Changing Storm Climate, Phase I report to: the U.S.  Department of Commerce, Economics of Global Change Program,  National Oceanographic and Atmospheric Administration, April, 1994. (S. Ratick, A.  Solow, J. Eastman, W. Jin, H. Jiang).

 “Assessing the Vulnerability of Coastal Communities to Extreme Storms:  The Case of Revere, MA., USA,” Mitigation and Adaptive Strategies for Global Change 3: 59-82, 1998.  (G. E. Clark, S. C. Moser, S. J. Ratick, K.Dow, W.B.  Meyer, S.Emani, W. Jin, J. X. Kasperson, R.E. Kasperson and H.E. Schwartz).


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