The Three Categories of Rock

igneous rock Image:

igneous rock


Passionate about learning and expanding her awareness of the world, Valerie Varnuska of Westbury, NY, studies a variety of scientific concepts. Valerie Varnuska pursues a particular interest in geology and in the types of rocks that form on Earth.

Geologists classify rocks into three main types. The first, igneous rock, develops when liquid magma from deep inside the earth begins to cool. This hardens the magma into a solid state.

When it cools inside the earth, magma becomes a type of igneous rock known as intrusive rock. This rock can eventually surface through erosion of the rock layers above it. Other deposits of magma come to the surface as liquid lava from a volcano and cool at exposure to the atmosphere.

Igneous rock forms the majority of the earth’s surface. On top of this lies a layer of pebbles, sand, shells, and other materials of various origin. When this debris collects and pieces attach to one another, it creates sedimentary or secondary rock. Often soft and occasionally fragile, it is by far the most likely rock type to contain fossils.

The final type of rock, metamorphic, occurs when an igneous or sedimentary rock comes into contact with intense heat and pressure. This effects structural change and transforms the rock into something extremely sturdy and erosion-resistant. The process of change may also cause the metamorphic rock to have a layered appearance, while minerals that collect on its surface may develop into crystals.


Miocene Epoch-Era Gomphotherium Elephant Fossils Discovered in Florida

Elephant Fossils pic

Elephant Fossils

A science enthusiast, Valerie Varnuska of Westbury, NY discovered a passion for fossils. Valerie Varnuska makes an effort to learn more about fossils by staying current on paleontology work happening in America.

In recent news, a pair of teachers from Santa Cruz City Schools in California uncovered large fossils of a Miocene Epoch-era gomphotherium elephant. The fossils were found during a dig in Gainesville, Florida, and consisted of the elephant’s rib and neck vertebra as well as the tusk and humerus. Teachers Erin Petersen Lindberg and Rebecca Mussetter worked alongside scientists from the University of Florida in a program funded by the National Science Foundation, which aims to enhance education in paleontology within middle and high school curriculums.

Fossils of the prehistoric elephant have been found as far south as Panama. The animal’s journey to North America from the Old World extended north toward California and continued on to other regions of the United States, where fossilized remains of the elephant rest. Unlike elephants with origins from Africa and Asia, the Miocene Epoch-era gomphotherium elephant was much smaller in size and had four conical tusks.