Earth system
Geological provinces and tectonic context
Where geological environments are, how they came to be there, and how well anybody knows where their edges run. A curated and expanding corpus — not a map of Earth, and not a basis for locating anything.
A geological region and a drawing of where it is are two different records. A craton is not a polygon; a polygon is one published opinion about where a craton is, at one scale, by one group, on one date. Where two such opinions disagree, Lithoen keeps both rather than averaging them into an outline nobody published.[1, 2]
The author of the plate model used here writes that his coordinates are precise to about sixty metres and adds, in the same paragraph, that accuracy never equals precision. Everything in this section follows from taking that seriously: every geometry states what it means, how certain its edge is, and what was done to it between the ground and the screen.[1, 2]
Tectonic setting is recorded as something a region passed through, never as something it is, and a documented context for a mineral system is never a reason to expect one anywhere. The settings involved are among the largest features on Earth; the systems found in them are not.[1, 2]
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What a geological province is
A named, map-scale region distinguished by its geology and its history. Its identity is the name and the rocks; its outline is a separate thing entirely, and there may be several of those.
Why geological boundaries are not exact
A coordinate can be precise to sixty metres and still be in the wrong place. The author of the plate model Lithoen uses says so himself, and everything in the spatial architecture follows from taking him seriously.
Cratons, shields and platforms
A craton is stable continental lithosphere. A shield is the part of one you can see. They are not two things, and the difference matters more than the words suggest.
Plates, models, and what a boundary line is
Every plate boundary you have ever seen drawn belongs to a model. Model PB2002 divides Earth into fifty-two plates and marks thirteen more regions where it says a rigid plate does not describe the motion at all.
Large igneous provinces: observed, and not explained
A definition made entirely of size, rate and position — and deliberately silent about cause. Lithoen records the provinces and does not attribute them.
Why tectonic context does not prove a deposit
Every mineral system in this corpus is documented in a tectonic setting. Every one of those settings is vastly larger than the systems found in it, and one system barely depends on tectonics at all.
Plates, and the model they belong to
Twenty-four plates from model PB2002, each with the outline that model gives it. A plate boundary is a line in a model, and Lithoen names the model on every one.
Tectonic plate
Pacific Plate
The largest tectonic plate, dominantly oceanic, whose boundaries include the San Andreas transform system and the subduction zone marked by the Mariana Trench.
Tectonic plate
North American Plate
A major tectonic plate carrying most of North America, bounded on its west by the San Andreas transform system and on its east by the Mid-Atlantic Ridge.
Tectonic plate
Eurasian Plate
A major plate carrying Europe and most of Asia. It separates from the North American Plate along the Mid-Atlantic Ridge and converges with the Indian Plate along the Himalayan collision zone.
Tectonic plate
African Plate
A major plate carrying Africa and part of the surrounding ocean floor. It is being actively split in East Africa, where a new spreading centre may be developing.
Tectonic plate
Somali Plate
The eastern part of what is often mapped as a single African Plate, separated from it in plate models by the East African Rift. Whether the rift has yet made two plates is a question about how much relative motion a model needs before it draws a boundary.
Tectonic plate
Antarctic Plate
A major plate carrying Antarctica and a wide surround of ocean floor. It is unusual in being almost entirely ringed by spreading centres, so that it grows on nearly every side and subducts along almost none.
Tectonic plate
Australian Plate
A major plate carrying Australia, part of the Indian Ocean floor and the southern part of New Guinea. Its northern edge is a long convergent zone running from Indonesia to New Zealand, and its motion is among the fastest measured for a large plate.
Tectonic plate
South American Plate
A major plate carrying South America and the adjacent South Atlantic sea floor: overriding the Nazca Plate on its west, diverging from Africa on its east.
Tectonic plate
Nazca Plate
An oceanic plate of the eastern Pacific that is being subducted beneath the South American Plate along the Peru–Chile trench, driving Andean uplift and seismicity.
Tectonic plate
Indian Plate
The plate carrying the Indian subcontinent, whose collision with Eurasia raised the Himalaya and the Tibetan Plateau and continues to shorten the crust today.
Tectonic plate
Arabian Plate
A plate carrying the Arabian Peninsula, separated from the African Plate by the Red Sea — an ocean basin caught in the act of opening.
Tectonic plate
Philippine Sea Plate
An oceanic plate of the western Pacific. The fast-moving Pacific Plate converges against it, and the Mariana Trench marks where subduction occurs.
Where the model does not apply
Thirteen regions PB2002 calls orogens: areas where deformation is distributed and no rigid plate describes the motion. They are not orogenic belts.
Geological region
Persia–Tibet–Burma diffuse deformation zone
The largest orogen in model PB2002, running from the Zagros through Tibet to Burma. Deformation across it is distributed over thousands of kilometres, which is why a rigid-plate description fails there and why Bird’s subduction criteria explicitly exclude the Zagros, Pamirs, Himalaya and Tien Shan.
Geological region
Alps diffuse deformation zone
PB2002 marks the Alpine region as an orogen: a zone where the rigid-plate model does not describe the motion, because deformation is distributed rather than confined to a boundary. It overlaps the Alps but is not the Alpine orogenic belt, and its outline is a statement about where a plate model stops working.
Geological region
Gorda–California–Nevada diffuse deformation zone
A zone of distributed deformation spanning the Gorda plate, the California margin and the Basin and Range, where Pacific–North America motion is shared among many structures rather than taken up on the San Andreas alone.
Geological region
Alaska–Yukon diffuse deformation zone
A zone of distributed deformation across interior Alaska and the Yukon, where motion transferred from the southern Alaska margin is spread across many faults.
Geological region
Philippines diffuse deformation zone
A zone of distributed deformation through the Philippine archipelago, where convergence is partitioned across several structures rather than taken up on one boundary.
Geological region
Ninetyeast–Sumatra diffuse deformation zone
A zone of distributed deformation in the northeastern Indian Ocean, where the Indo-Australian plate deforms internally rather than behaving rigidly — one of the clearest cases of intraplate deformation on Earth.
Geological region
Laptev Sea diffuse deformation zone
A zone of distributed deformation where the Arctic spreading system meets the Siberian margin and the boundary between the Eurasian and North American plates becomes indistinct.
Ancient continental lithosphere
Cratons and the shields that expose them. A shield is not a smaller craton — it is the part of one you can see, and the block continues under the cover.
Geological region
Kaapvaal Craton
An Archean craton of southern Africa, described by the USGS stratiform chromite model as stable and as the host of the Bushveld Complex. It is the setting of the largest layered intrusion on Earth, which holds most of the world’s chromium.
Geological region
Zimbabwe Craton
An Archean craton of southern Africa, host to the Great Dyke, which was emplaced along the Archean–Proterozoic boundary. Adjacent to the Kaapvaal Craton across the Limpopo belt.
Geological region
Superior Province
A large Archean craton of central and eastern Canada, made of granite-greenstone terrains including the Bird River and Sachigo greenstone belts. It is the largest area of Archean crust exposed on Earth.
Geological region
Slave Craton
An Archean craton of northwestern Canada, shown in the USGS chromite model beneath the Proterozoic cover that hosts the Muskox intrusion, and bounded by the Wopmay orogen.
Geological region
Wyoming Province
An Archean province of the western United States, described by the USGS chromite model as containing the Beartooth Range as a major block. The Stillwater Complex lies along its faulted front.
Geological region
Yilgarn Craton
An Archean craton of Western Australia. Its Eastern Goldfields region hosts nickel sulfide deposits associated with komatiite lavas, and its weathering profiles host nickel-cobalt laterites — two entirely different mineral systems on the same ancient crust, separated by billions of years.
Geological region
Canadian Shield
The great exposure of Precambrian basement across northern and central Canada — the surface expression of the cratons beneath, not a separate body from them. The Muskox intrusion, the Mackenzie dyke swarm and the Coppermine River flood basalts lie on its northwestern part.
Geological region
Fennoscandian Shield
The exposed Precambrian basement of Finland, Sweden, Norway and northwestern Russia. The USGS chromite model places the Burakovsky intrusion on its East Karelian block, described as a prominent suture zone.
Geological region
Limpopo Belt
The high-grade belt between the Kaapvaal and Zimbabwe cratons in southern Africa. Lithoen records it because the chromite deposit model places the Bushveld Complex in "the Limpopo province of South Africa", which is a statement about where the intrusion sits relative to two ancient blocks and the belt between them.
Large igneous provinces
Provinces defined by extent, volume and rate — and by a definition that deliberately says nothing about cause.
Geological region
Siberian Traps
A continental flood basalt province of northern Siberia, cited by the USGS magmatic nickel model as an example of a large igneous province. The Noril’sk intrusions, which host the world’s largest magmatic nickel-copper-PGE deposits, belong to its plumbing system.
Geological region
Deccan Traps
A continental flood basalt province of western and central India, cited by the USGS magmatic nickel model among the examples of large igneous provinces.
Geological region
Karoo Igneous Province
A continental flood basalt province of southern Africa, cited by the USGS magmatic nickel model among the examples of large igneous provinces.
Geological region
Columbia River Basalt Province
A continental flood basalt province of the northwestern United States, cited by the USGS magmatic nickel model among the examples of large igneous provinces.
Geological region
North Atlantic Igneous Province
A volcanic rifted margin province spanning the northern Atlantic, cited by the USGS magmatic nickel model as an example of a large igneous province of that kind rather than a continental flood basalt.
Geological region
Ontong Java Plateau
An oceanic plateau of the western Pacific, cited by the USGS magmatic nickel model as the representative example of a large igneous province in an oceanic setting.
Events
Named episodes bounded in time and place. An event is not a process: subduction operates wherever conditions allow; the Bushveld was emplaced once.
Geological event
Bushveld emplacement
The emplacement of the Bushveld Complex into the Kaapvaal Craton at about 2.05 billion years ago — a magmatic episode that produced the largest layered intrusion known and most of the world’s chromium.
Geological event
Great Dyke emplacement
The emplacement of the Great Dyke into the Zimbabwe Craton at about 2.46 billion years ago, along what the USGS chromite model calls the Archean–Proterozoic boundary.
Geological event
Stillwater emplacement
The emplacement of the Stillwater Complex in Montana at about 2.7 billion years ago, along the structure now marked by the faulted front of the Beartooth Range in the Wyoming Province.
Geological event
Muskox–Mackenzie magmatic event
A magmatic episode at about 1.27 billion years ago on the northwestern Canadian Shield, comprising the Muskox intrusion, the Mackenzie dyke swarm and the Coppermine River continental flood basalts, which the USGS chromite model treats as coeval and possibly cogenetic.
Geological event
Assembly of Pangaea
The series of collisions through Devonian to Permian time that brought the continents together into Pangaea. The USGS Mississippi Valley-type model connects that interval to about 61 percent of the lead and zinc in dated deposits of that class, through the basinal fluid flow that orogenic loading drives.
Geological event
Breakup of Pangaea
The dispersal of Pangaea from Triassic through Jurassic time. The Mississippi Valley-type model records that few deposits of that class formed during it — a period of major plate dispersal producing few of the basins and few of the fluid drives that the class requires.
Crust that arrived
A terrane is a block whose history differs from its neighbours and which is interpreted to have arrived where it now sits. Terrane boundaries are commonly interpretive.
Geological region
New Caledonia Ophiolite
An obducted ophiolite sheet in the southwest Pacific, named by the USGS laterite model among the accreted terranes and obducted ophiolites on which nickel-cobalt laterites have developed. Ophiolite is oceanic lithosphere emplaced onto a continental margin — crust that arrived rather than formed where it now sits.
Hub last updated 2026-09-07. Every entry above is a structured record; the bracketed references link to the entities whose claims support each statement.