March 2014

Steno's Principles of Stratigraphy

Steno's Principles of Stratigraphy are four basic principles that govern the way that sedimentary rocks are deposited an…

Growth Fault

Growth Fault Growth Fault a fault in sedimentary rock that forms contemporaneously and continuously with deposition so t…

Contact Metamorphism

Contact Metamorphism Contact metamorphism is the name given to the changes that take place when magma is injected …

Volcanic Bombs

Volcanic Bombs. Fresh Volcanic Bomb photo by J.D. Griggs Volcanic bomb is a pyroclast which was semi-molten (visc…

Hotspots the Hottest places on Earth

The places known as hotspots or hot spots in geology are volcanic regions thought to be fed by underlying mantle that is …

Oil Shale

Oil Shale Oil shale , also known as kerogen shale, is an organic-rich fine-grained sedimentary rock containing keroge…

Types of Drainage Patterns

Drainage pattern a pattern created by stream erosion over time that reveals characteristics of the kind of rocks and geol…

Cleavage of Minerals

Cleavage is the tendency of minerals to break along definite crystallographic structural planes. Cleavage planes are like t…

Volcanology

Volcanology   is the study of volcanoes, lava, magma, and related geological, geophysical and geochemical phenomena. The …

Luster of Minerals

Minerals may be categorized according to whether they are  opaque  or  transparent . A thin section of a…

The Streak of Minerals

Streak plates with pyrite (left) and rhodochrosite (right) The streak (also called "powder color") of a …

Andradite

Locality: Dashkesan (Dashkezan) Co-Fe deposit, Dashkesan, Daşkəsən (Daskasan; Dashkyasan) District, Azerbaijan. F…

Acicular Natrolit from India

Natrolite is a tectosilicate mineral species belonging to the zeolite group. Formula: Na2Al2Si3O10 · 2H2O System: Ort…

Volcanic Ash the Tiny Disaster

Volcanic ash consists of fragments of pulverized rock, minerals and volcanic glass, created during volcanic eruptions, …

Fantastic Azurite

Azurite |‪#‎Geology Formula: Cu3(CO3)2(OH)2 System:Monoclinic Colour:Azure blue, blue, light ... Lustre:Vitr…

Chalcedony (Agate)

Most agates occur as nodules in volcanic rocks or ancient lavas, in former cavities produced by volatiles in the origin…

Determine the Sequence of Geologic Events

The order of geologic events can be determined using the principles of superposition, original horizontality, and cross-…