from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A gneiss derived from a sedimentary rock.
from The Century Dictionary and Cyclopedia
- n. In petrography, a gneiss formed by the metamorphism of sedimentary deposits: opposed to orthogneiss.
The geology of the region ranges from the recent river alluvia and Karoo sandstones to the ancient gneiss and paragneiss overlain by the lithosols of the basement complex of the escarpment.
It covers approximately 35 km of favourable strike length where a gold corridor was discovered by SIRIOS within a mineralized altered paragneiss.
This is a mineralized zone located in a paragneiss.
Biotite-bearing units are paragneiss / paraschist (i.e., derived from sedimentary protolithologies.)
The reconnaissance work suggests that the pegmatite dykes are subhorizontal and at N360 degrees / 90 degrees, and that they are grouped in essaim in fold hinges within the paragneiss belonging to the Laguiche Group.
(pyrite, pyrrhotite, galena, sphalerite, + / - chalcopyrite) within altered sheared paragneiss