metamorphism
Let an agent explain metamorphism and its kinds, describe how metamorphic rocks are recognised and classified by grade and facies, relay standard references, and separate metamorphism from weathering, diagenesis and melting.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify
Researched by: Claude
Purpose and description
Let an agent explain metamorphism and its kinds, describe how metamorphic rocks are recognised and classified by grade and facies, relay standard references, and separate metamorphism from weathering, diagenesis and melting.
The change of a rock in the solid state through heat, pressure and chemically active fluids, without melting, producing new minerals and textures; metamorphism occurs regionally in mountain belts, around igneous intrusions, along faults and at meteorite impacts, and turns shale into slate and schist, limestone into marble and sandstone into quartzite.
What it is for: Not for anything; a geological process.
It can be explain the process and its agents; describe kinds and settings; explain grade, facies and index minerals; distinguish from diagenesis and melting.
Distinguishing features
Solid-state recrystallisation
Controlled by temperature, pressure and fluids
Graded by facies and index minerals
Records tectonic history
What it looks like
Not visible as a process; seen in foliated or crystalline rocks such as slate, schist, gneiss and marble.
Physical character
temperature range: about 150-850 degrees C - below melting
pressure range: up to several GPa - in deep and ultrahigh-pressure settings
How it is recognised
Solid-state change of rock by heat, pressure and fluids
Regional, contact, dynamic and shock settings
Diagenesis is lower temperature; melting produces igneous rock
Related models
is a kind of - rock transformation
produces - the result
is related to - regional setting
is contrasted with - lower temperature changes
In practice
Families and kinds
regional metamorphism
contact metamorphism
dynamic or fault metamorphism
shock metamorphism at impacts
burial and hydrothermal metamorphism
retrograde metamorphism
coal rank change as a related process
Standards and regulation
IUGS recommendations on metamorphic rock nomenclature
Geological survey mapping standards
Failure modes and hazards
Confusing metamorphism with weathering or melting
Misreading textures
Outdated facies boundaries
Also called
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.metamorphism
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.
Process How metamorphism works.
Process.
Agents
Heat, pressure, fluids.
Agents
Agents.
- How do temperature, pressure and fluids change rocks in the solid state? definition
- Is the process metamorphism, diagenesis, weathering or melting? boundary
Kinds
Kinds and settings.
Kinds
Kinds.
- What kinds of metamorphism occur in which tectonic settings? definition
- Which entry fits the specific kind? action
Classify Grade and facies.
Classification.
Facies
Facies and index minerals.
Facies
Facies.
- What are metamorphic facies and index minerals, and how do they indicate conditions? definition
- Which entry fits metamorphic facies? action
Rocks
Metamorphic rocks.
Rocks
Rocks.
- How are metamorphic rocks named and recognised? provenance
- Which entry fits a specific rock? action
Measure Conditions and dating.
Method.
Conditions
Thermobarometry.
Conditions
Conditions.
- How are pressures and temperatures of metamorphism estimated? measurement
- Which methods are standard? provenance
Dating
Dating.
Dating
Dating.
- How are metamorphic events dated? measurement
- Which entry fits geochronology? action
Context Tectonics and teaching.
Context.
Tectonics
Tectonic meaning.
Tectonics
Tectonics.
- What does metamorphism reveal about mountain building and plate tectonics? provenance
- Which entry fits orogeny? action
Teach
Teaching.
Teach
Teaching.
- How is metamorphism taught, and which references are standard? provenance
- Which misconceptions arise? provenance
What the second pass must settle
- Should each kind be a separate entry?
- How should nomenclature references be linked?
- The registry entry has merged aliases for kinds and coal rank; should they be split off?