Each claim states how it is known and cites its evidence.
EstablishedA public-domain coastline, credited; no political boundaries, on any map.
General principle, shown here for context — not an observation about this record.
The coastline behind Lithoen’s static maps is Natural Earth 1:110,000,000 land, which its authors place in the public domain, stating that no permission is needed and that crediting them is unnecessary. Lithoen credits them anyway, because a map that does not say where its coastline came from cannot be checked. No political boundary is drawn from it or from anything else: political geography is not Lithoen’s subject, and border styling would imply editorial positions Lithoen does not hold.
- precision note: The basemap is a background, not evidence. Nothing in the corpus is claimed from it.
- generality: GENERAL_PRINCIPLE
Evidence support: Supported by the cited evidence · one source
Evidence: Patterson n.d. · Peer-reviewed
Inferred4.54 Ga before present
The best age for the Earth is 4.54 billion years, obtained from lead isotope ratios in iron meteorites rather than from any Earth rock.
- method: Lead–lead isotope systematics using presumed single-stage leads coupled with lead ratios in troilite from the Canyon Diablo iron meteorite.
- assumption: Assumes the Earth and the other solid bodies of the Solar System formed at the same time and are therefore of the same age.
Evidence support: Supported by the cited evidence · one source
Evidence: Newman 1997 · Primary authority
InferredThe oldest preserved rocks are ordinary surface rocks, implying a substantial prior history now lost.
Rocks exceeding 3.5 billion years in age occur on every continent, and they are not primordial crust but lava flows and sediments deposited in shallow water — evidence that Earth history began well before them.
Evidence support: Supported by the cited evidence · one source
Evidence: Newman 1997 · Primary authority
EstablishedInner core, outer core, mantle and crust.
Described mechanically rather than compositionally, the Earth is often divided into four major layers: inner core, outer core, mantle and crust.
- definition basis: A four-layer division that splits the core by physical state; it does not contradict the three-layer compositional division of crust, mantle and core.
Evidence support: Supported by the cited evidence · one source
Evidence: Wald n.d. · Primary authority
Established44.2 ± 1 TW
The total heat flux from the Earth to space is 44.2 terawatts, with an uncertainty of 1.0 terawatt.
- precision note: Quoted by the cited paper as the current total heat flux; it derives from compilations of global heat-flow measurements rather than from the geoneutrino experiment itself.
Evidence support: Supported by the cited evidence · one source
Evidence: Nature Geoscience 2011 · Peer-reviewed
EstablishedThree main compositional layers: crust, mantle and core.
The Earth is made up of three main compositional layers: crust, mantle and core.
Evidence support: Supported by the cited evidence · one source
Evidence: Kious 1996 · Primary authority
Established12,750 km
The Earth is about 12,750 kilometres in diameter.
- precision note: Approximate figure, as stated by the source.
Evidence support: Supported by the cited evidence · one source
Evidence: Kious 1996 · Primary authority
EstablishedThe terrestrial rock record does not reach Earth’s formation; the age is obtained indirectly.
Earth’s own rock record cannot date the planet’s formation, because the oldest rocks have been recycled and destroyed by plate tectonics; no rock in its original primordial state has been found.
Evidence support: Supported by the cited evidence · one source
Evidence: Newman 1997 · Primary authority
Measured4.3 Ga before present
Single zircon crystals preserved in younger sedimentary rocks in Western Australia give radiometric ages of as much as 4.3 billion years, making them the oldest terrestrial materials yet found.
- method: Radiometric dating of detrital zircon crystals.
- precision note: The source rocks for these crystals have not been found; the crystals are older than any surviving rock.
Evidence support: Supported by the cited evidence · one source
Evidence: Newman 1997 · Primary authority
Measured4.03 Ga before present
The oldest rocks found on Earth so far are the Acasta Gneisses of northwestern Canada, at 4.03 billion years.
- method: Radiometric dating by a number of methods, with consistent results.
- precision note: A lower bound on the age of preserved crust, not on the age of the Earth.
Evidence support: Supported by the cited evidence · one source
Evidence: Newman 1997 · Primary authority
EstablishedTwo main sources: radiogenic decay and residual primordial heat.
Heat within the Earth comes from two main sources: radioactive decay of uranium, thorium and potassium, and residual heat left from the planet’s formation.
Evidence support: Supported by the cited evidence · one source
Evidence: Kious 1996 · Primary authority
Measured95 percent
Earth’s main field — the part generated in the core — accounts for over 95 per cent of the magnetic field strength measured at the surface.
- precision note: Stated by the source as "over 95%": a lower bound, not a central estimate.
- method: Separation of the observed field into core, crustal and external contributions in geomagnetic field modelling.
Evidence support: Supported by the cited evidence · one source
Evidence: NOAA National Centers for Environmental Information n.d. · Primary authority
InferredRadiogenic decay supplies roughly half the total heat flux; primordial heat is not exhausted.
Geoneutrino observations from KamLAND and Borexino indicate that heat from radioactive decay contributes about half of Earth’s total heat flux, and therefore that the planet’s primordial heat supply has not yet been exhausted.
- method: Combination of geoneutrino flux measurements from the KamLAND and Borexino liquid-scintillator detectors.
- precision note: "About half" is the authors’ own phrasing; the split between primordial and radiogenic heat remains uncertain.
Evidence support: Supported by the cited evidence · one source
Evidence: Nature Geoscience 2011 · Peer-reviewed