Heat productivities

▪ Table

Heat productivities

isotope heat productivity, A

(calories per gram per year)

U-235 4.29

U-238 0.71

natural uranium 0.73

Th-232 0.20

K-40 0.22

natural potassium 27(10⁻⁶)

Rb-87 130(10⁻⁶)

natural rubidium 36(10⁻⁶)

major rock province

U

ppm abundances

Th

ppm

K

% heat productivity, A (in 10⁻¹³ calories per cubic centimetre per second)

oceanic crust 0.42 1.68 0.69 0.71

continental shield crust (old) 1.00 4.00 1.63 1.67

continental upper crust (young) 1.32 5.28 2.15 2.20

See as table:

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