Diogenites, which formed in magma chambers deep in Vesta's crust, are composed mostly of orthopyroxene and hypersthene
, with smaller amounts of olivine, plagioclase, troilite, and chromite.
Caption: Figure 2: Geological map of the study area ( E: 1/1000000): 1, anatexite granite; 2, schist; 3, mica schist; 4, syenite; 5, tray basalt; 6, syn-tectonic granite (Monzonitic, discordant with biotite); 7, anatexite or migmatite with biotite); 8, embrechite gneiss; 9, Upper gneiss (grenatifere with two micas); 10, quartzite (Lom group, Mbalmayo-Bengbis, and Ayos); 11, Sedimentary formation of cretaceous; 12, upper mica schist with chlorite (Poli group); 13, low gneiss (with biotite, amphibole, pyroxene, sillimanite and hypersthene
); 14, amphibolite (para- and ortho-: greenstones); 15, pelites; 16, post-tectonic granite (microgranite); 17, calcoalkaline orthogneiss.
Name 1 Carbuncle 2 K feldspar 3 Albite 4 Tektite 5 Magnetite 6 Demantoid 7 Oolitic hematite 8 Pink pyroxene 9 Idocrase 10 Black hematite 11 Biotite 12 Hornblende 13 Calcite 14 Labradorite 15 Magnesite 16 Rhodonite 17 Reniform hematite 18 Banded siliceous rocks 19 Diopside 20 Selenite 21 Alabaster 22 Anhydrite 23 Moonstone 24 Barite 25 Hypersthene
Table 2: Emission lines for classification based on major elements from geological samples.
Pyroxene is generally hypersthene
normative (23.38-24.33%) with lesser normative composition of diopside (3.64-8.24%).
Phenocrysts of orthopyroxenes are represented by hypersthene
. They form euhedral to subhedral colourless crystals of columnar shape, which are partly grouped in small clusters together with plagioclases.
The normative average of these nine samples is quartz 32.3 %, corundum 2.66 %, orthoclase 18.95 %, albite 22.32 %, anorthite 12.2 %, hypersthene
7.06 %, magnetite 1.38 %, ilmenite 1.03 %, and apatite 0.28 %.
This fall was described by Ambrogio Soldani (1736-1808) and the meteorites were once known as "soldanites" or "giovannites." They are olivine and hypersthene
Compared to other granodiorite, tonalite and diorite porphyries of the Moldanubian Zone of the Bohemian Massif (Nemec 1970, 1974), granodiorite porphyries from the eastern margin of the Klenov massif have lower content of normative quartz (8.5-10.6 %), higher content of normative hypersthene
(8.1-16.6%) and complete absence of normative corundum.
It is characterized as a Plinian eruption, of explosive power and with a widely dispersed rhyodacite ash (Hanson, 1965) composed of glass, plagioclase, hornblende, hypersthene
, and magnetite (Lerbekmo and Campbell, 1969).
Na2O + K2O (8.8 wt%) and contains small amounts of diopside acmite and hypersthene
in the CIPW norms that are dominated by albite quartz and orthoclase.