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An element a in a magma (M, ∗) has the two-sided cancellation property (or is cancellative) if it is both left- and right-cancellative. A magma (M, ∗) is left-cancellative if all a in the magma are left cancellative, and similar definitions apply for the right cancellative or two-sided cancellative properties.
A loop has the weak inverse property when (xy)z = e if and only if x(yz) = e. This may be stated in terms of inverses via (xy) λ x = y λ or equivalently x(yx) ρ = y ρ. A loop has the inverse property if it has both the left and right inverse properties. Inverse property loops also have the antiautomorphic and weak inverse properties.
Texas is approximately bisected by a series of faults that trend southwest to northeast across the state, from the area of Uvalde to Texarkana.South and east of these faults, the surface exposures consist mostly of Cenozoic sandstone and shale strata that grow progressively younger toward the coast, indicative of a regression that has continued from the late Mesozoic to the present.
A further control on the morphology and characteristics of a deposit is the water to magma ratio. It is considered that the products of phreatomagmatic eruptions are fine grained and poorly sorted where the magma/water ratio is high, but when there is a lower magma/water ratio the deposits may be coarser and better sorted. [4]
In some compositions, at high pressures without water crystallization of enstatite is favored, but in the presence of water at high pressures, olivine is favored. [12] Granitic magmas provide additional examples of how melts of generally similar composition and temperature, but at different pressure, may crystallize different minerals.
An example of an inverse spinel is Fe 3 O 4, if the Fe 2+ (A 2+) ions are d 6 high-spin and the Fe 3+ (B 3+) ions are d 5 high-spin. In addition, intermediate cases exist where the cation distribution can be described as (A 1− x B x )[A x ⁄ 2 B 1− x ⁄ 2 ] 2 O 4 , where parentheses () and brackets [] are used to denote tetrahedral and ...
The calc-alkaline magma series is one of two main subdivisions of the subalkaline magma series, the other subalkaline magma series being the tholeiitic series. A magma series is a series of compositions that describes the evolution of a mafic magma, which is high in magnesium and iron and produces basalt or gabbro, as it fractionally crystallizes to become a felsic magma, which is low in ...
Today, the Christmas Mountains caldera complex, as well as the dome, is heavily eroded, exposing the deep structure of the complex. The complex is the type location for laccocalderas. Laccocalderas differ from conventional calderas, being relatively small and developing over thin, shallow laccolithic magma chambers rather than deeper bodies ...