What is an ammonite and when did it live?
GeologyAmmonites lived during the periods of Earth history known as the Jurassic and Cretaceous. Together, these represent a time interval of about 140 million years. How did the Ammonite live? Where did ammonites live? Ammonites lived all around the world. Like their modern-day cephalopod relations, they were exclusively ocean-dwelling. They tended to live in more
Why are some vents white smokers and some black smokers?
Geology“Black smokers” are chimneys formed from deposits of iron sulfide, which is black. “White smokers” are chimneys formed from deposits of barium, calcium, and silicon, which are white. Underwater volcanoes at spreading ridges and convergent plate boundaries produce hot springs known as hydrothermal vents. Are white smokers or black smokers hotter? White smokers typically occur
Where is the Popigai crater?
GeologySiberia, RussiaSiberia, Russia, is tied with the Manicouagan Crater as the fourth largest verified impact crater on Earth. A large bolide impact created the 100-kilometre (62 mi) diameter crater approximately 35 million years ago during the late Eocene epoch (Priabonian stage). Where is the crater that hit Earth? Chicxulub crater Impact crater/structure Coordinates 21°24′0″N 89°31′0″WCoordinates:
How many seamounts are in the Hawaiian chain?
Geology80over 80 identified undersea volcanoes, stretches about 6,200 km (3,900 mi) from the Aleutian Trench in the far northwest Pacific to the Lōʻihi Seamount, the youngest volcano in the chain, which lies about 35 kilometres (22 mi) southeast of the Island of Hawaiʻi. Are the Hawaiian Islands seamounts? The Hawaiian Islands were formed by volcanic
What is the process of seafloor spreading and subduction?
GeologyAt subduction zones, the edge of the denser plate subducts, or slides, beneath the less-dense one. The denser lithospheric material then melts back into the Earth’s mantle. Seafloor spreading creates new crust. Subduction destroys old crust. What are steps in the process of seafloor spreading? What are the steps in seafloor spreading? Magma comes out
Where rhyolite is found?
GeologyThe silica content of rhyolite is usually between 60% to 77%. Rhyolite has the mineralogical composition of granite. Rhyolite rocks can be found in many countries including New Zealand, Germany, Iceland, India, and China, and the deposits can be found near active or extinct volcanoes. Where does rhyolite come from? Rhyolite is an extrusive igneous
What is an example of a fumarole?
GeologyCorbetti Caldera, Ethiopia, where a geothermal power station is under construction. Taupo Volcanic Zone, New Zealand, where fumaroles support a unique and critically endangered ecosystem. Mount Usu, Japan. Valley of Desolation in Morne Trois Pitons National Park in Dominica. What is a fumarole of a volcano? Definition: Fumaroles are openings in the earth’s surface that
How do you test for calcite?
GeologyDescription: The mineral calcite is tested against a cold, dilute (10%) solution of hydrochloric acid (HCl). Observation reveals a reaction that is characteristic of this mineral, and helps in identifying calcite. What would be the easiest way to identify calcite? Identifying calcite is relatively easy. Firstly, it is generally light-coloured (mostly white) and is translucent
What are the top 5 most dangerous volcanoes in North America?
GeologyThe 18 volcanoes included in the “very high threat” category are: Kīlauea, Hawaii. Mount St. Helens, Washington. Mount Rainier, Washington. Redoubt Volcano, Alaska. Mount Shasta, California. Mount Hood, Oregon. Three Sisters, Oregon. Akutan Island, Alaska. What is the deadliest volcano in North America? The May 18, 1980 eruption of Mount St. Helens (Washington) was the
When was the earth covered with water?
Geology4.4 billion years ago4.4 billion years ago contrasts sharply with the hot, hostile world typically depicted in textbooks. A Cool Early Earth? the earth glowed like a faint star. When was the Earth totally covered with water? between 2.5 and 4 billion years ago It suggests that most of Earth’s water was on the surface