1. GIS in Geology
Lesson 2
Miloš Marjanović

2. Principles of modeling in Geology
Introduction
Model definition and modeling scope
Geological model
GIS definition, relations and rolls
GIS-Geology integration
Material formats and resources in Geology
Geological modeling procedure using GIS

3. Principles of modeling in Geology
Model definition and modeling scope:
No uniform deffinition, but Model is a simplified representation of reality – system (Küne, Stachowiack, Stainmüller)
They are crucial for scientific development in any discipline (Physics, Chemistry, Biology, Geology, Meteorology, Urban planning, Psychology…) due to interoperability, comparativeness, generalization, communication and other model features
Classifications of the model by
Temporal state: static, dynamic
Dimension and resolution: 0-nD; macro-micro
Indeterminism: deterministic, probabilistic, stochastic
Data type: raster, vector
Modeling techniques: white, gray, black-box models
A system is modeled consecutively through model building, model application and model assessment
What is a model?

4. Principles of modeling in Geology
Geological model
What is Geological model?
Difficult to define (observational empiricism, perceptional limitations, uncertainty)
Intuitively developed through practice (depends on education, training and experience)
A way of transferring or presenting information that captures the essence of the character of the soil/rock mass in a simple form that meets the objectives (Sullivan)
So it is a PROCESS not a RESULT!
Modeling principles:
From general to particular (regional to local)
Balancing the complexity (scale vs. information, accuracy vs. representativeness)
Think 5-dimensionally
Extrapolate
Always regard lithology, soil/rock properties, groundwater and structures
Simplification to the essence

5. Principles of modeling in Geology
Building a Geological model
Formulation of hypothesis
Observation/measurement
Merging
Re-examining and testing of hypothesis
Developing of modeling skills
Clustering of data (sorting patterns)
Selecting important
Perception of details and “getting the whole picture”
Learning habits (new discovery says “learn different things simultaneously and in different rooms, with different music”)
Reasoning
Simplification
Using scientific methodology
Obtain good mentoring
Savants

6. Principles of modeling in Geology
Term GIS? A System, analysis or science?
GIS in relation to other disciplines
Purpose: to visualize, analyze combine, merge together…
Fields of application
Geological mapping
Mineral mapping
Hazard/Risk zonation (analysis)
Hydrogeological modeling (Schalstad, Dynlam, Trigg)
Site selection (road route, windmill farm location, building construction site)
RS - spectral signature in relation to geology, vegetation…
Geophysical
GIS is an organized assemblage of computer hardware, software, geographical data and personel designed/trained to efficiently capture, store, update, manipulate analyze and display all forms of geographically referenced information (Voženílek)
Contouring and surface modeling
General statistics
Spread- sheets
Desktop and Web publishing
Geostatistics
Desktop mapping
Image Processing (IP)
Database Management Systems (DBMS)
Computer Aided Drawing (CAD)
Artificial Intelligence(AI)
Geographic Information System (GIS)

7. Principles of modeling in Geology
GIS-Geology integration
GIS data structure revolution
Storage
Generation of new data
Editing data
Visualization
Integration
Isolated
Loose
Tight
Full

8. Principles of modeling in Geology
Material formats and resources in Geology
Maps
Borehole logging
Satellite and aerial imagery
Geophysical data
GPS data
Field logs (digital or hard-copy archived)

9. Principles of modeling in Geology
Material formats and resources in Geology
Logic, Nominal, Ordinal, Scalar & Directional Data
2-2,5D objects
Raster - pixels
Vector - vertices, lines, surfaces
3D objects
Blocks - voxels
Boreholes and interpolating
surfaces
Thematic surfaces

10. Principles of modeling in Geology
Geological modeling procedure using GIS
Knowledge (about object, area or phenomenon of interest)
Conceptual model:
Providing a theoretical framework of a case study (example of mineral exploration, landslide analysis)
Selecting necessary vs. available conditions
Deciding what type of analysis is feasible
Expectations

11. Principles of modeling in Geology
Embedding GIS
Step MODEL BUILDING
Building spatial database (the most time-consuming)
Selecting the area and scale (motif)
Selecting the working projection
Data assemblage – input
Spatial database for different research levels and end-users
Scale concept:
Small scale: preliminary investigation (zonation)
Medium scale: (further research, e.g. mapping, directed by the small scale research)
Large scale: (detailed analysis of the selected areas)

12. Principles of modeling in Geology
Input model types
Raster
Vector
Spatial data input requirements
Geo-referencing
Digitizing (manual, scanning) and converting
Calculating (interpolation) and processing (raster oriented algebra, e.g. different filters, enhancements…)
Conversion to target data type

13. Principles of modeling in Geology
Step MODEL APPLICATION
Spatial analysis, processing and modeling of inputs
Reclassification
Morphometric calculations
Buffering
Statistics
Querying
Type of modeling technique/approach
“White box” (physically-based) models
“Grey box” (statistical) models
“Black box” (AI approach) models

14. Principles of modeling in Geology
Step MODEL APPLICATION
Integrating the input models in some fashion (heuristic, deterministic, statistic, probabilistic, artificial intelligence)
Two maps integration
Multiple maps integration

15. Principles of modeling in Geology
Step MODEL ASSESSMENT
Statistical comparison of expected vs. obtained results
Accuracy (%)
Chi-Square-Tests
Entropy/Uncertainty
Kappa-index
ROC curves (AUC)

16. Geological background and rock unit contact map
Temporary outputs of processing/modeling stage (contact distance buffers, density distributions etc)
Geochemical data maps of different components (from tables)
Geophysical maps (also from table or profile or cross-section data)
Geological background and rock unit contact map
Final map of mineral potential of sulphidic mineralization (favorability map, ranging from 0-1)
Temporary output maps, conecting some of the sources together (e.g. geological and geochemical)
A - Stratigraphic factor
B - “Heat factor”
C - Alteration factor
Outline scheme for Mineral exploration example

17. GIS in Geology
Exercise 1
Miloš Marjanović

18. Exercise 1
Explore geological survey web pages of different countries world-wide, and make your selection (choose a country)
Make a short (2 pg. max) report on your assignment. The report should regard:
Description of the Web Map service provided by the chosen survey
Comment of the interface according to your appeal (is it user- friendly, interactive, good or poor graphic design, versatile – provides many different geological thematic layers and metadata)
Maps’ availability for public (cost-free) use and to which extent
Your suggestions for improvement (if any)
One of the exercise term will be reserved for your oral and interactive presentation of this exercise