IG
SED
The Rock Cycle
"What is the solid Earth made of, and how is it transformed?"
The Material Transformation
Geology is one of the hidden architects of Geography. A ridge is not simply “there.” We must ask: What rock? What structure? How resistant? The Earth continually transforms material from one state into another, driving the relief of the planetary surface.
MAGMA
↓ (Crystallisation)
IGNEOUS ROCK
↓ (Weathering & Erosion)
SEDIMENT
↓ (Lithification)
SEDIMENTARY ROCK
↓ (Heat & Pressure)
↓ (Melting)
MAGMA
The 34 Domains of Earth Materials
Deconstructing Realm 04
DOMAIN 01
Extrusive
Intrusive
The Mineral Realm
- Naturally Occurring
- Inorganic Solid
- Definite Composition
- Crystalline Structure
Mineral Properties
- Colour & Lustre
- Streak & Cleavage
- Mohs Hardness Scale
- Specific Gravity
Mineral Formation
- Cooling of Magma
- Precipitation / Evaporation
- Hydrothermal Processes
- Metamorphic Recrystallisation
Major Mineral Groups
- Silicates (Quartz, Feldspar)
- Carbonates & Oxides
- Sulfides & Sulfates
- Native Elements
Rock Assemblages
- Polymineralic vs Monomineralic
- Grain Size & Shape
- Texture & Fabric
- Colour Index
Igneous Rocks
- Plutonic (Intrusive)
- Volcanic (Extrusive)
- Cooling Rate & Crystal Size
- Porphyritic & Glassy Textures
Igneous Composition
FELSIC
INTER
MAFIC
- Felsic (Silica Rich)
- Mafic (Iron-Magnesium)
- Ultramafic
- Viscosity & Gas Content
Major Igneous Rocks
- Granite & Diorite
- Basalt & Gabbro
- Obsidian & Pumice
- Rhyolite & Andesite
Sedimentary Rocks
- Weathering & Erosion
- Transportation & Deposition
- Compaction & Cementation
- Lithification
Types of Sedimentary
- Clastic (Sandstone, Shale)
- Chemical (Limestone, Halite)
- Biochemical (Coal)
- Sedimentary Environments
Sedimentary Structures
- Stratification & Bedding
- Cross-Bedding & Ripple Marks
- Fossils & Burrows
- Depositional Indicators
Metamorphic Rocks
- Protolith (Parent Rock)
- Heat & Pressure Changes
- Regional vs Contact
- Recrystallisation
Metamorphic Textures
- Foliation & Banding
- Slaty Cleavage
- Mineral Alignment
- Non-Foliated Textures
Major Metamorphic Rocks
- Slate, Phyllite, Schist
- Gneiss (High Grade)
- Marble (from Limestone)
- Quartzite (from Sandstone)
The Rock Cycle
- Continuous Transformation
- No Fixed Starting Point
- Uplift & Burial Pathways
- Melting vs Lithification
Open vs Closed System
↓ IN
↓ OUT
- Material Recycling
- Energy Input (Sun & Core)
- Surface vs Internal Processes
- Geological Transformation
Weathering Controls
- Climate (Temp & Rain)
- Rock Type & Mineral Stability
- Relief & Vegetation
- Time
Geological Structure
- Dip & Strike
- Structural Attitude
- Massive vs Stratified Rocks
- Structural Control of Relief
Folds
→
→
- Compression Forces
- Anticline & Syncline
- Symmetrical vs Overturned
- Fold-Mountain Relationships
Faults
- Fracture with Displacement
- Normal & Reverse Faults
- Hanging Wall & Footwall
- Horst & Graben (Rift Valley)
Joints
- Fracture without Displacement
- Columnar Jointing
- Cooling vs Unloading Joints
- Joint-Controlled Weathering
Unconformities
- Break in Geological Record
- Angular Unconformity
- Erosion Surface
- Uplift, Erosion, Subsidence
Lithology
HARD
SOFT
- Rock Type & Composition
- Porosity & Permeability
- Resistance to Erosion
- Lithology-Landscape Link
Differential Erosion
- Hard vs Soft Rock Alternation
- Differential Weathering
- Structural Landscapes
- Bedding & Joint Controls
Rock-Landform Logic
- Resistant Cap Rocks
- Mesas & Escarpments
- Karst (Limestone) Landscapes
- Granite Tors & Inselbergs
Porosity & Permeability
- Pore Space Storage
- Ability to Transmit Fluids
- Fracture vs Pore Flow
- Rock-Water Interaction
Rocks & Soil
- Parent Material Control
- Mineral Weathering
- Residual vs Transported Soil
- Soil Chemistry & Fertility
Rocks & Groundwater
- Aquifers vs Aquitards
- Sandstone & Limestone Aquifers
- Groundwater Storage
- Geological Water Control
Geological Resources
- Metallic Minerals (Iron, Gold)
- Non-Metallic (Mica, Gypsum)
- Building Stones
- Resource Distribution
Fossil Fuel Traps
- Sedimentary Basins
- Source Rock & Reservoir Rock
- Cap Rock Seals
- Structural Traps (Anticlines)
Economic Geology
- Ore Grade & Gangue
- Geological Reserves
- Metallogenic Provinces
- Resource Extraction
Rocks & Civilization
- Construction Stone & Cement
- Metals & Industrial Minerals
- Settlement & Industry Location
Geological Hazards
- Landslides & Rockfalls
- Subsidence & Karst Collapse
- Fault Rupture
- Geological Risk
The Great Rock Engine
- Magma → Rock → Sediment
- Uplift → Weathering
- Burial → Heat → Metamorphism
- The Ultimate Transformation
Exit Portal
We have examined the solid materials of the Earth and the tectonic forces that uplift them. But the moment a rock is exposed to the atmosphere, it begins to die. It is attacked by water, wind, ice, and gravity. Now, we must witness the destruction of the rock cycle.