Shale and Basalt Types and Facts
Types
Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale
Alkaline Basalt, Boninite, High Alumina Basalt, Mid Ocean Ridge Basalt (MORB), Tholeiitic Basalt, Basaltic trachyandesite, Mugearite and Shoshonite
Features
Easily splits into thin plates, Generally rough to touch, Very fine grained rock
Has High structural resistance against erosion and climate, Very fine grained rock
Archaeological Significance
Famous Monuments
Jantar Mantar in India
Easter Island in the Polynesian Triangle, Pacific Ocean, Gateway of India in Mumbai, India, Gol Gumbaz in Karnataka, India
Types of Shale and Basalt
Some rocks according to their use or texture are classified into different types. Know more about Shale Texture and Basalt Texture. Types of Shale are Red Shale, Black Shale, Green Shale, Grey Shale and Yellow Shale whereas the types of Basalt 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. Shale and Basalt 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. Shale and Basalt were for creating petroglyphs.