Exogenic & Endogenic Processes Flashcards
- occurs in Earth’s surface, driven by external force (ex. solar energy)
-destructive forces, result in destruction of landforms via weathering and erosion
-weathering, mass wasting, erosion, deposition
Exogenic Processes
-driven by energy and forces originating deep within the Earth
-constructive forces, create relief features on Earth’s surface
-main source of energy is Earth’s internal heat
-produce visible after-effects after sudden damage caused by earthquakes and volcanic eruptions
Endogenic Processes
It is the on-site breakdown of rocks and its eventual transformation into sediments.
Weathering
Physical breakdown of a rock into unconnected grains or chunks without changes in its composition.
Physical Weathering or Mechanical Weathering
Natural cracks/joints are formed and it breaks the rocks into rectangular blocks, irregular chunks, or onion-like sheets
Exfoliation, Physical Weathering
The rock freezes which causes the joints to expand and grow which causes the rock to detach
Frost Wedging, Physical Weathering
Plants growing on a rock’s surface pry it open due to joints expanding
Root wedging, Physical Weathering
Salt crystallizes which pushes apart surrounding grains which weakens the rock
Salt Wedging, Physical Weathering
Occurs when rock is exposed to high temperature, outer layer expands due to baking
Thermal Expansion, Physical Weathering
-Causes (substances in the air and in rain)
-Occurs when there are chemical changes in the rock’s composition. It is a surface or near-surface process.
Chemical Weathering
Minerals are dissolved in water
Dissolution, Chemical Weathering
Water reacts with minerals which breaks minerals down
Hydrolysis, Chemical Weathering
-Reaction of oxygen with minerals in the rocks.
-Forms oxides
-Rusting
Oxidation, Chemical Weathering
Water is absorbed which causes expansion within the rock
Hydration, Chemical Weathering
Water is absorbed which causes expansion within the rock
Hydration, Chemical Weathering
Polluting gases dissolve in rainwater which makes stronger acids. Causes damage
Acidification, Chemical Weathering
-Causes (plants and animals)
-Occurs when rocks are weakened by the different biological agents like plants and animals.
-Special type of physical and chemical weathering
Biological Weathering
Caused by burrowing animals and human activities
Biological Weathering by Physical Means
Plants and animals produce acidic substances that react with rocks
Biological Weathering by Chemical Compounds
-generated during Earth Formation
-internal heat energy accumulated by dissipation in a planet
-source of heat is accretion energy
Primordial Heat
Conversion of kinetic energy of smaller planetary objects into heat as they collided on ____.
Accretion Energy
-generated by long term radioactive decay or the disintegration of natural radioactive elements
-thermal energy released as a result of spontaneous nuclear disintegrations
-mantle convection
Radiogenic Heat
Heating in the mantle
Mantle convection
Heating in the mantle
Mantle convection
-Form when preexisting or parent rocks are altered by heat, pressure, and the chemical activity of fluids.
Metamorphic Rocks
Changes in form
Metamorphism
Changes in form
Metamorphism
Matter changes form but not chemical identity
Physical change
A chemical reaction occurs and new products are formed
Chemical Changes
-Occurs due to heating, with or without burial of rocks that lie close to a magma intrusion.
-results to nonfoliated metamorphic rocks
Contact metamorphism
-Occurs over broad areas of the crust usually in convergent plate boundaries
-affected by heat, temperature, and differential stress
-results to foliated metamorphic rocks
Regional Metamorphism
-Occurs when sediments are buried deeply enough that the heat and pressure cause minerals to begin to recrystallize and minerals grow.
-occurs in sedimentary basins
Burial Metamorphism
-High-pressure metamorphism resulting from the crushing and shearing of rocks during tectonic movement,
-produces mylonites
Dynamic or Cataclastic Metamorphism
-Occurs along the mid-ocean ridge, spreading centers where heated seawater percolates through hot, fractured basalt
Hydrothermal Metamorphism
-Takes place when the heat and shock waves from meteor or asteroid impact transform rocks immediately around the impact site.
-Extreme compression of the shock wave causes mineral chemical structure change
Shock metamorphism
-Causes rocks to be pulled apart that result to lengthening and break apart
-Stretches the rock which results to elongation and shortening
-Can be found at divergent plate boundaries
Tensional Stress
-Dominant force is directed towards each other
-Squeezes the rocks which results to shortening and elongation
-Causes the rocks to fold and fracture
-Found at convergent plate boundaries
Compressional Stress
-Dominant force is directed towards each other but not on the same axis
-Forces slide pass each other in opposite directions
-Results to slippage and translation
-Found at transform plate boundaries
Shear Stress
-Magma intrudes into a low-density area of another geologic formation such as sedimentary rock structure. When it cools to solid rock, it forms pluton.
Intrusion
Sheared, highly deformed rocks formed by dynamic or cataclastic metamorphism
Mylonites
Sheared, highly deformed rocks formed by dynamic or cataclastic metamorphism
Mylonites
Intrusion of magma that wells up from below the surface
Pluton
-Magma escapes or extrudes through lava
Extrusion
These can be fire fountains of liquid rock or thick, slow-moving rivers of molten material.
Lava eruptions
Formed when magma solidifies
Tephra or volcanic ash
-Decompression
-Flux Melting
-Heat transfer melting
-Partial melting
Magma formation
-Tensional Stress
-Compressional Stress
-Shear Stress
Behaviors of rocks under stress
-Contact Metamorphism
-Regional Metamorphism
-Burial Metamorphism
-Dynamic/Cataclastic Metamorphism
-Hydrothermal Metamorphism
-Shock Metamorphism
Types of Metamorphism
-Primordial Heat
-Radiogenic Heat
Sources of Internal Heat
-Oxidation
-Dissolution
-Hydrolysis
-Hydration
-Acidification
Chemical Weathering
-Exfoliation
-Frost Wedging
-Root Wedging
-Salt Wedging
-Thermal Expansion
Physical/Mechanical Weathering
-Endogenic Processes
-Exogenic Processes
Earth’s processes
-Involves the upward movement of Earth’s mostly solid mantle.
-Hot material rises to a low pressure area
-Overlying pressure/decompression allows mantle rock to melt and form magma.
-Often occurs at divergent plate boundaries, where tectonic plates separate.
Decompression Melting, Magma Formation
-Hot, liquid rock, intrudes into Earth’s cold crust.
-The liquid rock solidifies and loses its heat
-Hot rock from below intrudes into the cooler plate above
-This process transfers heat and forms magma
-Happens at convergent plate boundaries, where tectonic plates are crashing together
Heat Transfer Melting, Magma Formation
-Water or carbon dioxide enters a rock (chemical weathering)
-The compounds cause rocks to melt at lower temperatures which forms magma
-Occurs around subduction zones
Flux Melting, Magma Formation
Rocks - High Temperature - Partial Melting - Magma Formation
-It does not melt uniformly.
-Minerals with lower melting points turn into liquid magma while the higher melting points remain as a solid crystal.
Partial Melting, Magma Formation
