What are surface lakes glaciers?
Geology and GeographyWhat is a glacial lake called? In geology, a proglacial lake is a lake formed either by the damming action of a moraine during the retreat of a melting glacier, a glacial ice dam, or by meltwater trapped against an ice sheet due to isostatic depression of the crust around the ice. What is glacier
What happened at Lake Nyos?
GeologyAt 9:30 p.m. on August 21, 1986, a cloudy mixture of carbon dioxide (CO2) and water droplets rose violently from Lake Nyos, Cameroon. As the lethal mist swept down adjacent valleys, it killed over 1700 people, thousands of cattle, and many more birds and animals. What caused the disaster at Lake Nyos? Carbon dioxide was
How is an ice age defined?
Geologyice age, also called glacial age, any geologic period during which thick ice sheets cover vast areas of land. Such periods of large-scale glaciation may last several million years and drastically reshape surface features of entire continents. What is an ice age simple answer? An ice age is a period in Earth’s history when the
What are 5 ways that organisms can be preserved as fossils?
GeologyFossils form in five ways: preservation of original remains, permineralization, molds and casts, replacement, and compression. What are the 5 types of fossils of organisms? There are five types of fossils: Body Fossils. Molecular Fossils. Trace Fossils. Carbon Fossils. Pseudofossils. What are the 6 ways fossils can be preserved? What are the 6 types of
What formation is created in the rift of a spreading sea floor?
GeologyThe phenomenon is known today as plate tectonics. In locations where two plates move apart, at mid-ocean ridges, new seafloor is continually formed during seafloor spreading. What is formed when sea floor spreads? Keeping Earth in Shape At subduction zones, the edge of the denser plate subducts, or slides, beneath the less-dense one. The denser
What is a solid mixture of minerals or particles?
GeologyA rock is a natural, solid mixture of minerals or grains. These grains are made of mineral crystals, bits of minerals, or rock fragments. Sometimes a rock contains the remains of an organism or volcanic glass. Processes on Earth’s surface can cause rocks to break apart into fragments. What is a mixture of mineral and
What does it mean if a rock has a fine texture?
GeologyFine-grained textures generally indicate magmas that rapidly cooled at or near the Earth’s surface. Fast cooling prevents crystals from growing very large. The cutoff between fine- and coarse-grained textures is about 1 mm. What is meant by a rock that has fine texture? The fine-grained texture indicates the quickly cooling lava did not have time
What is a glacial valley called?
GeologyGlacial troughs, or glaciated valleys, are long, U-shaped valleys that were carved out by glaciers that have since receded or disappeared. Troughs tend to have flat valley floors and steep, straight sides. What are valleys called? Valleys are the low points between hills, and they are also known as vales. What is a flooded glacial
Where does Dolomite come from?
GeologyDolomite is formed by the replacement of the calcite ions by the magnesium ions. Depending upon the ratio of the Mg ions in the crystal lattice they have different names (Figure 1). Modern dolomite formation has been found to occur under anaerobic conditions in supersaturated saline lagoons in Brazil. Where is dolomite found? Although rock
How many eras are there in Earth’s history?
Geologythree erasthree eras, each of which includes a number of periods. They, in turn, are subdivided into epochs and stage ages. In an epoch, a certain section may be especially well known because of rich fossil finds. What are the 6 eras? It is subdivided into six periods, the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and