Unearth your Geology IQ

Geology is a field of study concerned with the structure and dynamics of Earth.

The branches of geology include geophysics, geochemistry, petrology, mineralogy, paleontology, and environmental geology.

Geophysics studies the physical properties of Earth such as the interior structure, magnetic field, flow of heat, force of gravity, and movement of seismic waves.

<p>Geochemistry studies the chemistry of Earth, including the distribution of minerals, rocks, soil, life forms, water, and atmosphere; carbon, nitrogen, phosphorus, and water cycles.</p> Signup and view all the answers

<p>Petrology studies the origin, occurrence, structure, and history of metamorphic and igneous rocks, as well as the changes and transformation of rocks.</p> Signup and view all the answers

<p>Mineralogy studies minerals in Earth's crust, as well as lunar and meteorite samples.</p> Signup and view all the answers

<p>P-waves are compressional waves that move by compressing and expanding the ground as they propagate.</p> Signup and view all the answers

<p>S-waves are shear waves that move the ground up and down and side to side.</p> Signup and view all the answers

<p>S-waves are referred to as secondary waves because they arrive at seismic locations after P-waves.</p> Signup and view all the answers

<p>S-waves can only travel through solids and are unable to pass through air and liquid (water and magma).</p> Signup and view all the answers

<p>Seismologists determine that Earth's outer core is molten because S-waves cannot pass through it.</p> Signup and view all the answers

<p>When P and S waves arrive later than expected and the S waves are weakened, it signifies the presence of the asthenosphere or partially molten areas of the mantle.</p> Signup and view all the answers

<p>When P waves encounter the liquid core, they slow down.</p> Signup and view all the answers

<p>S waves disappear at the mantle/core boundary because the outer core is liquid and S-waves cannot propagate through liquids.</p> Signup and view all the answers

<p>The four main layers of the Earth are the crust, mantle, outer core, and inner core. The crust is the outermost layer, with varied thickness and composition. The mantle is the thickest layer, composed mainly of iron, magnesium, and calcium-rich silicate minerals. The outer core is a liquid layer of iron and nickel, while the inner core is a solid ball made mostly of iron and nickel.</p> Signup and view all the answers

<p>The mantle is mainly composed of iron, magnesium, and calcium-rich silicate minerals.</p> Signup and view all the answers

<p>About 4.6 billion years ago, during the formation of the solar system, meteorite debris bombarded Earth, repeatedly remelting it. As Earth cooled, dense materials sank towards its center, forming the iron-nickel core. The mantle formed between the crust and core, and the less dense magma rose to the surface and cooled, forming the crust.</p> Signup and view all the answers

<p>Seismic activity refers to vibrations that travel underground as a result of the sudden movement of materials within Earth. Geologists study seismic waves produced by earthquakes to obtain indirect evidence about Earth's interior. By analyzing the speed and behavior of these waves, they can determine the composition, temperature, and density of the materials inside Earth.</p> Signup and view all the answers

<p>P waves are compressional or longitudinal waves that travel faster than S waves. They can move through any type of material, including solids and liquids. S waves are transverse waves that can only travel through solids. By studying the behavior and speed of these waves during seismic events, geologists can infer the composition and state of the materials in Earth's layers.</p> Signup and view all the answers

<p>Geologists use indirect evidence, such as seismic wave readings, and direct evidence, such as studying rock samples obtained from drilling or volcanic eruptions, to learn about Earth's interior.</p> Signup and view all the answers