Magmas also contain many other chemical elements in trace quantities.
The settlement of this problem awaits the solution of the more general problem of the origin and crystallization of magmas.
With the recognition of evidence of a deeper source related to magmas, the emphasis has swung rapidly to the other extreme.
Facts of this kind seem to favor the position of certain geologists that magmas may assimilate the rocks they invade.
This is the so-called "inorganic" theory, that oil comes from magmas and volcanic exhalations.
Basaltic magmas, generated in the upper mantle beneath the ridge, rise along fractures through the basaltic layer.
Basaltic magmas, generated in the mantle beneath the ridge, rise along fractures through the granitic layer.
Magmas, generated near the base of the mountain root, rise slowly or intermittently along fractures in the crust.