Earth Science: EarthQuakes The Earth is constantly shifting below our feet. The magnitude of this movement is usually too weak to be sensed by humans, yet various factors can result in highly destructive and intense earthquakes. In areas where this occurs frequently, safety precautions are of vital importance. Causes The constant motion within the layers … Read more
Earth Science: Plate Tectonics – Primeval Continents Pangaea, Laurasia, Gondwana: these names are taken from the Earth’s history. Today the outlines of these three former continents can be recon- structed on the basis of models simulating continental drift. The location of each continent today is the result of geologically recent tectonic changes. The further back … Read more
Earth Science: Origins and Geology – Reconstruction In order to reconstruct how and when the continents migrated into their current positions and the route they are now following, researchers have developed measuring procedures to observe the traces of rock “memory.” There are traces of ferrous silicates almost everywhere in the lithosphere. When molten rock is … Read more
Earth Science: Plate Boundaries For new ocean crust to continue to form, older parts of the crust must first be destroyed. This happens when tectonic plates collide with each other. When lithospheric plates meet each other, one plate can slide below the other in a process called subduction. This process, and the changes in the … Read more
Earth Science: Origins and Geology – Plate Tectonics Earthquakes in Afghanistan, volcanoes in Java, ice-capped mountains in South America, and mid-ocean ridges and trenches are all natural phenomena caused by shifting continents or forming oceans. They are the results of hidden geological forces within the Earth. Earth in Motion How did the Atlantic Ocean spread, … Read more
Earth Science: Sedimentary Rocks Sedimentary rocks are the most common type of rock on Earth. All sedimentary rocks are formed in a similar manner: by sedimentation, compaction, or cementation of many smaller particles of mineral, animal, or plant origin. Sedimentary rocks are categorized into three groups: clastic, chemical, and bio- genic. Clastic sediments, such as … Read more
Earth Science: Magmatic and Metamorphic Rocks The rock material that makes up the Earth is a mixture of natural minerals. Some rocks are created from molten mass as it cools, others are formed by the high temperatures and extreme pressure conditions of Earth’s interior. Rocks are composed of a variety of minerals, the presence and … Read more
Earth Science: Origins and Geology – Minerals – Structure Minerals—the basic ingredients of rock-provide many of our most important raw materials. They usually occur in the form of crystals, which have been treasured throughout history for their colorful variety and refractive properties. Crystals are solid substances whose ions, atoms, or molecules are arranged in a … Read more
Earth Science: Rocks Humans have mined rocks and minerals since the Stone Age, using them as raw materials. Gems are frequently used for jewelry because of their form, color, and luster. The study of the origin, characteristics, and composition of rocks is known as petrology, while mineralogy studies the origin, characteristics, and composition of minerals. … Read more
Earth Science: Structure Of The Earth’s Crust The Earth’s crust is the thin and rigid outer shell of the Earth. The Earth has a continental and an oceanic crust, differing in thickness, density, and type of rock content, as well as the age and origin of the rock material. The thin outer shell of the … Read more
