Revolutionary theory about  the origin of the Earth crust

According to Prof. Vicente Sanchez-Cela.

Danilo Anton

It all started with the accretion and compaction of planetesimals for the formation of the planet Earth.

As a result of these processes impact minerals of high density were formed. They were related to the impactites (rocks formed after a meteoric impact). These dense minerals had a very similar composition to the crust (quartz and feldspar) but with higher density.

In the crust silicon dioxide (SiO2) crystallizes as quartz but in a high density (mantle) environment crystallized in higher density SiO2 minerals such as coesite and stishovite.

It should be noted that quartz density is 2.65, while coesite and stishovite densities are respectively 2.92 and 4.35. All three (quartz, coesite and stishovite) have the same formula (SiO2). Another difference betweem these three minerals is the packing of their atoms, quartz is trigonal, coesite is monoclinic and stishovite is tetragonal.

Similarly, crust feldspars with density 2.56 (potassium feldspar) and 2.61 (sodium feldspar), have been preceded (during planetary formation and subsequent geological eras) by minerals of high density: K Hollandite and Na Hollandite with approximate density 4. Both crystallize in the monoclinic system. Other high density minerals that may exist in the mantle are the perovskite silicate (magnesium iron silicate and calcium silicate) and post-perovskite (magnesium silicate). The latter have densities higher than 3.

According to this approach, we can consider that in the crust the family of silicate minerals of low density (granitic) predominate while the high density family of silicate minerals (which Sanchez Cela call " densialites ") are dominant in the mantle.¹

Despite having different densities the chemical composition of both petro-mineralogical groups (crust and mantle groups) are similar.

Sanchez-Cela's theory is based on the phase changes of dense minerals in the outer mantle (coesite, stishovite, hollandites, perovskites and post-perovskites) which increase in volume decreasing their density. The typical mineral phase of low density silicates (quartz, feldspars) is generated in this way. This change in phase is exothermic producing magmatic fusion, intrusions and volcanic eruptions.

At the same time, the expansion in volume of the rock masses produce the formation of orogenic changes in continents and oceans and other protruding geological and geomorphologic features.

Danilo Antón, based on the theory of Vicente Sanchez Cela (La Energía en los Procesos Geológicos, 2005).

¹ Silicon dioxide SiO2, currently crystallizes mainly as quartz, before crystallized with higher density forming coesite or stishovite. It should be noted that quartz has a density of 2.65, coesite, 2.92 and stishovite 4.35. All three have the same formula (SiO2). Another difference is the packing of atoms. quartz is trigonal, coesite is monoclinic and stishovite tetragonal.

Similarly feldspars with density 2.56 (potassium feldspar) and 3.61 (sodium feldspar) in the crust, have been preceded (when planetary formation and subsequent geological eras) by higher density minerals: K Hollandite and Na Hollandite with approximate density of 4. Both crystallize in the monoclinic system. Other high density minerals that may existing in the mantle are the perovskite silicate (magnesium iron silicate and calcium silicate) and post-perovskite (magnesium silicate).