Fig: A view of the Triassic Succession, Nammal Gorge, Salt Range, Punjab, Pakistan. (After Iqbal et.al.
2013)
FIELD GEOLOGY
GEOL. 508 (3CH)
BS Geology (6th Semester)
Course Contents
• Introduction, topographic and geological maps.
• Methods and techniques of surface and subsurface geological mapping.
• Introduction to instrumental geological mapping.
• Correlation techniques.
• Field description of igneous, metamorphic and sedimentary rocks.
• Modes of geological illustration including structural contour, isopach
and lithofacies maps, block and fence diagrams.
• Field mapping, preparation of geological maps and cross sections.
Recommended Books
• Introduction to Field Geology. Bevier, M. L., 2006. McGraw-Hill Ryerson.
• Geology in the Field by Compton, R.R., 1985, John Wiley & Sons.
• Elements of Field Geology by Himus, G.W. & Sweeting, G.S., 1968.,
University Tutorial Press Ltd.
• Field Geology by Lahee, F.H., 1961, McGraw Hill.
• The study of rocks and rock materials in their
environment and their relation to one another.
OR
• It involves integrating(mixing) spatial,
Introduction descriptive, structural, petrologic, and temporal
data to understand the geological makeup and
history of an area.
• Result is:
• Geological Maps, Cross sections and written reports
4
Introduction…
• Primary focus – Geological maps
• Other purposes – for specific reasons like sampling for geochemical
analysis or fossil identification etc.
• These maps are then used as a guide for different other projects i.e.
mineral & hydrocarbon exploration, natural hazard assessment and
land-use planning etc.
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A map is a visual representation of an area.
Geologic/Geological Map is a map showing the distribution of rock
units and structures across a region, usually on a plane surface.
Introduction…
Figure: Geological map of Salt Range with location of measured section of the Nammal Formation, western Salt Range, Pakistan (after Afzal and Butt, 2000) 7
➢Standardized symbols, patterns, and colors on a map:
• To depict rock units, their ages, structures, and
important localities, such as fossil and mineral
occurrences.
Introduction…
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Any cross sections and geological reports that
accompany a geologic map represent additional
ways of presenting geologic data and
interpretations.
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Introduction…
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Introduction…
Any scientific report can be broken down
into a number of basic parts. These are:
• Title page
• (contents)
Layout of a • Abstract
• Introduction
Geological • Main body
• Conclusions
Report • References
• Appendices
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Introduction…
• In short reports, some of these parts may be only a few lines
long.
• In others, even the Introduction may include several sub-
sections and the ‘body’ itself may consist of many sections
and sub-sections. It varies from project to project.
Introduction…
• Purpose, budget and time allotted for a mapping project.
• Interpretations and conclusions based on your observation in
the field and available data.
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Introduction…
WHAT MAKES A SUCCESSFUL FIELD GEOLOGIST?
• How to read a topographic map or air photograph or any base map and locate
yourself.
• Use of Brunton or Silva compass for measuring linear and planar structures.
• Use of portable GPS receivers, and knowledge of their limitations.
• Know how to locate and plot geologic data accurately on a base map.
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• Ability to recognize and measure sedimentary structures, structural
features (folds, faults — sense of movement, lineations, foliations; use of
stereonet).
• How to measure a stratigraphic section (use of Jacob’s staff or pogo
stick).
• Rock identification skills (hand sample and thin section; fresh and altered
rocks; mineralized assemblages).
• Ability to take organized, coherent, and legible notes.
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Introduction…
• Ability to collect properly trimmed rock and fossil specimens;
ability to recognize the appropriate rock to sample depending on
the purpose
• e.g., microfossil age determination, radiometric age determination — which
accessory minerals for which dating technique, alteration assemblages.
• Ability to visualize and think in three dimensions.
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Introduction…
• Ability to independently plan, execute and accurately plot the
results of a traverse.
• Ability to write reports in a timely manner; write reports that are
complete yet concise.
• Field safety.
• Have a positive attitude (every day, in all conditions, on all projects).
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Thanks
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