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2.4. General Geology (GGL)

This knowledge area covers the fundamental Earth materials, processes, and structures relevant to civil engineering: minerals, rocks, geologic structures, surface processes, geologic time, and the descriptive fundamentals of site geological characterization, as a foundation for, and complement to, the applied geotechnical design content covered in GTE.

Knowledge Area (KA)	Core Tier1	Core Tier2
2.4.1 Mineralogy	1	1
2.4.2 Petrology and the Rock Cycle	1	1
2.4.3 Structural Geology	1	1
2.4.4 Geomorphology, Weathering, and Erosion Processes	1	1
2.4.5 Geologic Time, Stratigraphy, and Geologic Mapping	1	1
2.4.6 Basic Surface and Groundwater Hydrology of Geologic Materials	1	1
2.4.7 Applied Geology	1	1
2.4.8 Rock Mass Characterization and Applied Rock and Soil Mechanics	1	1
2.4.9 Engineering Geological and Geotechnical Mapping	1	1
2.4.10 Soils and Rocks as Natural Resources for Construction Materials	1	1
2.4.11 Engineering Geology Applied to Roads and Canals	1	1
2.4.12 Engineering Geology Applied to Bridges, Tunnels, and Dams	1	1
2.4.13 Geological Hazards and Mass Movements	1	1

2.4.1. GGL/Mineralogy  (Core Tier1: 1 hr, Core Tier2: 1 hr) ↑ Back to top

Study of the most common rock-forming minerals, their distinctive physical properties, and the practical mineral identification methods relevant to civil engineering.
Topics:
Core

• Crystal structure and habit of minerals
• Main groups of rock-forming minerals: silicates, carbonates, oxides, and sulfates
• Mohs hardness scale and scratch tests
• Cleavage, fracture, and other diagnostic physical properties
• Luster, color, and streak as identification criteria
• Basic chemical composition and reaction with dilute hydrochloric acid

Learning Outcomes:
Core:

1. Identify the most common rock-forming minerals using physical properties [Familiarity]
2. Apply the Mohs scale to determine the relative hardness of mineral samples [Usage]
3. Distinguish similar minerals through cleavage, fracture, and luster [Assessment]
4. Relate the mineral composition of a rock to its expected engineering behavior [Familiarity]
5. Perform simple field tests (scratch, acid, luster) for mineral identification [Usage]

2.4.2. GGL/Petrology and the Rock Cycle  (Core Tier1: 1 hr, Core Tier2: 1 hr) ↑ Back to top

Formation processes, classification, and engineering properties of igneous, sedimentary, and metamorphic rocks, and their cyclic relationship within the rock cycle.
Topics:
Core

• Classification of intrusive and extrusive igneous rocks by texture and composition
• Sedimentary rock formation processes: erosion, transport, deposition, and lithification
• Classification of clastic, chemical, and biochemical sedimentary rocks
• Metamorphic processes: contact and regional metamorphism
• Classification of foliated and non-foliated metamorphic rocks
• The rock cycle and transformations between lithologic types
• Relevant engineering properties of rocks: strength, durability, and alterability

Learning Outcomes:
Core:

1. Classify hand samples of igneous rocks according to their texture and mineral composition [Assessment]
2. Explain the formation processes of sedimentary rocks and their engineering significance [Familiarity]
3. Recognize foliated and non-foliated metamorphic textures in hand samples [Usage]
4. Trace the pathways of the rock cycle among the three lithologic groups [Familiarity]
5. Qualitatively evaluate the suitability of a rock type for use as a construction or foundation material [Assessment]

2.4.3. GGL/Structural Geology  (Core Tier1: 1 hr, Core Tier2: 1 hr) ↑ Back to top

Principles of stress and strain in the Earth's crust, and the identification and interpretation of geologic structures -folds, faults, and joints- relevant to rock mass stability analysis and infrastructure site selection.
Topics:
Core

• Stress and strain concepts in rocks
• Fold types: anticlines, synclines, and their geometric elements
• Fault types: normal, reverse, and strike-slip
• Joint sets and their influence on rock mass strength
• Measurement and interpretation of strike and dip
• Unconformities and their significance in geologic history
• Influence of geologic structures on slope and excavation stability

Learning Outcomes:
Core:

1. Differentiate folds, faults, and joints based on their geometric features [Familiarity]
2. Measure the strike and dip of geologic planes using a geologic (Brunton-type) compass [Usage]
3. Interpret the orientation of structural discontinuities relative to an excavation or slope [Assessment]
4. Assess the influence of joint sets on the stability of a rock mass [Assessment]
5. Recognize unconformities and relate them to regional geologic history [Familiarity]

2.4.4. GGL/Geomorphology, Weathering, and Erosion Processes  (Core Tier1: 1 hr, Core Tier2: 1 hr) ↑ Back to top

Physical, chemical, and biological weathering processes of Earth materials, resulting landforms, and surface erosion processes relevant to evaluating site conditions in civil engineering projects.
Topics:
Core

• Physical weathering: thermal fragmentation, frost wedging, and unloading
• Chemical weathering: hydrolysis, oxidation, and dissolution
• Biological weathering and bioerosion
• Residual soil formation from in-situ weathering
• Main landforms: valleys, terraces, alluvial fans, and debris cones
• Water and wind erosion processes and mass wasting processes

Learning Outcomes:
Core:

1. Distinguish physical, chemical, and biological weathering types present at an outcrop [Familiarity]
2. Relate the degree of weathering of a rock to the expected quality of a rock mass [Usage]
3. Identify landforms and their geomorphological origin [Familiarity]
4. Evaluate the susceptibility of a slope to erosion and mass wasting processes [Assessment]
5. Apply weathering grade classification criteria to estimate the durability of rock materials in slopes [Usage]

2.4.5. GGL/Geologic Time, Stratigraphy, and Geologic Mapping  (Core Tier1: 1 hr, Core Tier2: 1 hr) ↑ Back to top

Principles of stratigraphy and relative geochronology, and the fundamental techniques for reading and interpreting geologic maps, stratigraphic columns, and geologic cross-sections.
Topics:
Core

• The geologic time scale and the magnitude of deep time
• Principles of relative dating: superposition, original horizontality, and cross-cutting relationships
• Construction and interpretation of stratigraphic columns
• Symbology and conventions of geologic maps
• Construction of geologic cross-sections from maps
• Stratigraphic discontinuities and their expression on geologic maps
• Basic field geologic mapping techniques

Learning Outcomes:
Core:

1. Explain the principles of relative dating to establish stratigraphic sequences [Familiarity]
2. Read and interpret standard geologic maps, including their symbology and legend [Usage]
3. Construct a geologic cross-section from a geologic map and strike/dip data [Assessment]
4. Correlate stratigraphic units between columns from different localities [Assessment]
5. Apply basic field geologic mapping techniques for a simple survey [Usage]

2.4.6. GGL/Basic Surface and Groundwater Hydrology of Geologic Materials  (Core Tier1: 1 hr, Core Tier2: 1 hr) ↑ Back to top

Introductory concepts on the occurrence and movement of surface and groundwater in relation to geologic materials -porosity, permeability, water table, and springs- as a descriptive foundation prior to applied engineering hydrology and hydrogeology.
Topics:
Core

• Porosity and permeability of soils and rocks
• Water table concept and the unsaturated zone
• Basic concepts of aquifer, aquitard, and aquiclude
• Springs, seeps, and their relationship to the geologic context
• Surface drainage patterns and their relationship to lithology and structure
• Water-rock interaction and its influence on weathering

Learning Outcomes:
Core:

1. Differentiate the concepts of porosity and permeability for different geologic materials [Familiarity]
2. Describe the position of the water table and its seasonal variation at a given site [Familiarity]
3. Relate the occurrence of springs and seeps to the local geologic and hydrogeologic context [Usage]
4. Identify surface drainage patterns characteristic of different geologic conditions [Assessment]
5. Explain conceptually the water-rock interaction and its role in chemical weathering [Familiarity]

2.4.7. GGL/Applied Geology  (Core Tier1: 1 hr, Core Tier2: 1 hr) ↑ Back to top

Introduction to the application of general geology to the preliminary characterization of sites for civil engineering works, including field geologic reconnaissance, descriptive rock mass classification, and identification of geologic hazards, as a descriptive preamble to applied geotechnical investigation.
Topics:
Core

• Preliminary geologic site reconnaissance
• Qualitative description of rock masses: degree of fracturing and weathering
• Types of geologic hazards: landslides, rockfalls, seismic and volcanic activity
• Use of aerial photographs and remote sensing imagery in geologic reconnaissance
• Basic elements of a preliminary geologic site report
• Use of field tools: geologic compass, GPS, hand lens, and rock hammer
• Influence of geologic conditions on infrastructure site selection

Learning Outcomes:
Core:

1. Conduct a preliminary geologic reconnaissance of a site of interest for civil engineering [Usage]
2. Qualitatively describe the degree of fracturing and weathering of a rock mass [Assessment]
3. Recognize the main types of geologic hazards that can affect an infrastructure project [Familiarity]
4. Use basic field tools to gather geologic information [Usage]
5. Prepare a preliminary geologic site report with basic recommendations for further studies [Assessment]

2.4.8. GGL/Rock Mass Characterization and Applied Rock and Soil Mechanics  (Core Tier1: 1 hr, Core Tier2: 1 hr) ↑ Back to top

Field characterization of rock mass discontinuities and quality, standard rock mass classification systems, and the influence of geological origin and weathering on the engineering behavior of rocks and soils, as a link between descriptive geology and applied rock and soil mechanics.
Topics:
Core

• Characterization of rock mass discontinuities: orientation, spacing, persistence, roughness, aperture, and infill
• Rock Quality Designation (RQD) and geotechnical core logging
• Rock mass classification systems: RMR, Q-system, and GSI
• Estimation of rock mass strength and deformability using the Hoek-Brown criterion
• Influence of weathering grade on rock mass mechanical behavior
• Influence of geological origin -residual versus transported- on soil engineering properties

Learning Outcomes:
Core:

1. Characterize rock mass discontinuities from field or core data [Usage]
2. Determine RQD and classify rock mass quality using RMR, Q, and GSI systems [Assessment]
3. Estimate rock mass strength and deformability parameters using the Hoek-Brown criterion [Assessment]
4. Relate weathering grade to expected rock mass mechanical behavior [Familiarity]
5. Relate the geological origin of a soil to its expected engineering properties [Usage]

2.4.9. GGL/Engineering Geological and Geotechnical Mapping  (Core Tier1: 1 hr, Core Tier2: 1 hr) ↑ Back to top

Purpose, types, and preparation of engineering geological and geotechnical maps for infrastructure planning and geotechnical hazard zonation, extending basic geologic map reading into maps prepared specifically for engineering decision-making.
Topics:
Core

• Types and purposes of engineering geological and geotechnical maps
• Geotechnical zonation and microzonation mapping for urban and infrastructure planning
• Specialized symbology and legends for engineering geological maps
• Use of GIS and remote sensing tools in geotechnical mapping

Learning Outcomes:
Core:

1. Distinguish the types and purposes of engineering geological and geotechnical maps [Familiarity]
2. Prepare a basic geotechnical zonation map for a project area [Usage]
3. Apply GIS tools to compile and present geotechnical mapping information [Usage]

2.4.10. GGL/Soils and Rocks as Natural Resources for Construction Materials  (Core Tier1: 1 hr, Core Tier2: 1 hr) ↑ Back to top

Geological evaluation of soils and rocks as natural resources for construction: aggregate and quarry sources, dimension stone, and basic quality control criteria for their use in civil engineering works.
Topics:
Core

• Geological sources and quality evaluation of aggregates for concrete and construction
• Site selection and geological evaluation of quarries and borrow pits
• Dimension stone and other rock and soil resources used in construction
• Basic quality control criteria and tests for construction material sources

Learning Outcomes:
Core:

1. Evaluate geological sources of aggregates and construction materials for quality and suitability [Usage]
2. Select and assess quarry and borrow-pit sites based on geological criteria [Assessment]
3. Apply basic quality control criteria to construction material sources [Familiarity]

2.4.11. GGL/Engineering Geology Applied to Roads and Canals  (Core Tier1: 1 hr, Core Tier2: 1 hr) ↑ Back to top

Application of engineering geology to the siting, design, and construction of linear infrastructure -roads and canals- including alignment selection, cut-slope stability, and embankment foundation conditions.
Topics:
Core

• Geological considerations for highway and road alignment selection
• Geological and hydrogeological conditions for canal siting and seepage control
• Structural geological controls on cut-slope stability along transportation corridors
• Geological and geotechnical conditions for road and canal embankment foundations
• Engineering geological mapping and hazard identification along linear infrastructure corridors

Learning Outcomes:
Core:

1. Evaluate geological conditions to support road and canal alignment selection [Assessment]
2. Assess seepage and foundation conditions for canal design based on geological survey [Usage]
3. Analyze structural geological controls on cut-slope stability along a transportation corridor [Assessment]
4. Prepare an engineering geological map identifying hazards along a linear infrastructure corridor [Usage]

2.4.12. GGL/Engineering Geology Applied to Bridges, Tunnels, and Dams  (Core Tier1: 1 hr, Core Tier2: 1 hr) ↑ Back to top

Application of engineering geology to the site selection and geological characterization of major infrastructure works -bridges, tunnels, and dams- across the phases of a project, from reconnaissance through design.
Topics:
Core

• Engineering geological studies required at each phase of an infrastructure project: reconnaissance, feasibility, design, and construction
• Geological and rock mass considerations for tunnel alignment, excavation method, and support selection
• Geological siting and foundation and abutment characterization for dams
• Reservoir geology: seepage, landslide-induced impoundment hazards, and sedimentation sources
• Geological considerations for bridge site selection and pier and abutment foundation conditions
• Comparative geological criteria for selecting sites and alignments among infrastructure alternatives

Learning Outcomes:
Core:

1. Identify the engineering geological studies required at each phase of an infrastructure project [Familiarity]
2. Evaluate rock mass conditions relevant to tunnel excavation method and support selection [Assessment]
3. Characterize the geological suitability of a site for dam foundations and abutments [Assessment]
4. Assess reservoir-related geological hazards including landslide-induced impoundment risk [Usage]
5. Evaluate geological conditions relevant to bridge foundation siting [Usage]

2.4.13. GGL/Geological Hazards and Mass Movements  (Core Tier1: 1 hr, Core Tier2: 1 hr) ↑ Back to top

Classification, recognition, and hazard/susceptibility assessment of mass movements and other geological hazards relevant to civil infrastructure, extending the basic hazard-type awareness introduced in GGL.EngineeringGeologyBasics into systematic hazard classification, mapping, and mitigation.
Topics:
Core

• Classification of mass movements: falls, topples, slides, flows, and lateral spreads
• Triggering and controlling factors of mass movements: geological, hydrological, and seismic
• Field recognition of landslide morphology and indicators of active or past instability
• Geological hazards from seismic and volcanic activity relevant to civil infrastructure
• Geological hazard susceptibility mapping and risk zonation
• Overview of structural and non-structural mitigation measures for geological hazards

Learning Outcomes:
Core:

1. Classify mass movements according to their mechanism and material type [Assessment]
2. Identify triggering and controlling factors of mass movements at a given site [Familiarity]
3. Recognize field indicators of landslide morphology and slope instability [Usage]
4. Prepare a geological hazard susceptibility map for a project area [Assessment]
5. Propose mitigation measures appropriate to a specific type of geological hazard [Usage]