
Petrology



What is the Black Stone of Mecca? What is the type of Black Stone?
The Black Stone of Mecca, Al-Ḥajaru al-Aswad, “Black Stone”, or Kaaba Stone, is a Muslim relic, which according to Islamic tradition dates back to the […]

What is Petrified Wood? How Does it Form?
What is Petrified Wood? Petrified wood is the name given to a special type of fossilized remains of terrestrial vegetation. It is the result of […]

What are Ripple Marks?
Ripple marks are sedimentary structures and indicate agitation by water (current or waves) or wind. Ripple marks are ridges of sediment that form in response […]


Differential Weathering
Masses of rock do not weather uniformly. Take a moment to look back at the photo of Shiprock, New Mexico, in Figure 1. The durable […]


Igneous Compositions
Compare and contrast the four basic igneous compositions: basaltic (mafic), granitic (felsic), andesitic (intermediate), and ultramafic. Igneous rocks are composed mainly of silicate minerals. Chemical […]

Diamictite
Diamictite is a poorly sorted or non-sorted terrigenous non-calcareous sedimentary rock. Diamictite is composed of widely variable clast sizes from clay to boulders.Diamictite is a […]