Phyllite and Basaltic Trachyandesite Types and Facts
Types
Phyllite
Alkaline Basalt, Boninite, High Alumina Basalt, Mid Ocean Ridge Basalt (MORB), Tholeiitic Basalt, Basaltic trachyandesite, Mugearite and Shoshonite
Features
Easily splits into thin plates, Is one of the oldest rock, Surfaces are often shiny
Has High structural resistance against erosion and climate, Very fine grained rock
Archaeological Significance
Types of Phyllite and Basaltic Trachyandesite
Some rocks according to their use or texture are classified into different types. Know more about Phyllite Texture and Basaltic Trachyandesite Texture. Types of Phyllite are Phyllite whereas the types of Basaltic Trachyandesite are Alkaline Basalt, Boninite, High Alumina Basalt, Mid Ocean Ridge Basalt (MORB), Tholeiitic Basalt, Basaltic trachyandesite, Mugearite and Shoshonite.During historic times, some rocks depending on their hardness were used to create Pictographs and Petroglyphs. Rocks which are hard were generally not used. Pictographs are paintings or drawings that have been placed or created on the surface of rock. Phyllite and Basaltic Trachyandesite were for creating pictographs. Petroglyph is an image which is carved into a rock. These are images created by removing part of a rock surface by incising, picking, carving or abrading, as a form of rock art. Phyllite and Basaltic Trachyandesite were for creating petroglyphs.