What formed the Columbia Plateau?
GeologyThe plateau formed between 6 million and 16 million years ago as the result of successive flows of basalt. Its northern border is marked by the Columbia River and the mouth of the Okanagon River. On the south, the plain includes the drainage of the Deschutes River in Oregon. What volcano formed the Columbia Plateau?
How are turbidites formed?
GeologyTurbidites are sea-bottom deposits formed by massive slope failures. Rivers flowing into the ocean deposit sediments on the continenal shelf and slope. How are turbidites formed and why are they geologically important? Turbidites provide a mechanism for assigning a tectonic and depositional setting to ancient sedimentary sequences as they usually represent deep-water rocks formed offshore
What are the 3 major island arcs?
GeologySome well-known examples of island arcs are Japan, Aleutian Islands of Alaska, Mariana Islands, all of which are in the Pacific, and the Lesser Antilles in the Caribbean. The abundance of volcanic rocks around the Pacific Ocean has led to the designation of the Pacific margin as a “Ring of Fire”. What is the most
How far out does the continental shelf extend?
Geology200 nautical miles200 nautical miles,” whichever is further. How far does continental shelf extend? A continental shelf typically extends from the coast to depths of 100–200 metres (330–660 feet). It is gently inclined seaward at an average slope of about 0.1°. In nearly all instances, it ends at its seaward edge with an abrupt drop
What is a fossil record?
Geologyfossil record, history of life as documented by fossils, the remains or imprints of organisms from earlier geological periods preserved in sedimentary rock. What is a fossil record and what does it do? The fossil record helps paleontologists, archaeologists, and geologists place important events and species in the appropriate geologic era. It is based on
What are the different types of seismic waves?
GeologyThere are three basic types of seismic waves – P-waves, S-waves and surface waves. P-waves and S-waves are sometimes collectively called body waves. What are the 4 types of seismic waves? Love Waves—surface waves that move parallel to the Earth’s surface and perpendicular to the direction of wave propagation.. P-wave Motion. P-wave:the primary body wave;
What is the difference between a fossil of a plant or organism and a trace fossil of an animal?
GeologyBody Fossils and Trace Fossils The fossils of bones, teeth, and shells are called body fossils. Most dinosaur fossils are collections of body fossils. Trace fossils are rocks that have preserved evidence of biological activity. They are not fossilized remains, just the traces of organisms. What is the difference between an animal and a trace
Which is the best evidence supporting the concept of seafloor spreading?
GeologySupporting Evidence for Seafloor Spreading First, samples of the deep ocean floor show that basaltic oceanic crust and overlying sediment become progressively younger as the mid-ocean ridge is approached, and the sediment cover is thinner near the ridge. What are the evidence that supports the theory of seafloor spreading? Harry Hess’s hypothesis about seafloor spreading
Why is Hawaii in the middle of the Pacific plate?
GeologyIn areas where the plates come together, sometimes volcanoes will form. Volcanoes can also form in the middle of a plate, where magma rises upward until it erupts on the seafloor, at what is called a “hot spot.” The Hawaiian Islands were formed by such a hot spot occurring in the middle of the Pacific
Why is a quick burial helpful In the fossilization process?
GeologyThe rapid burial of remains beneath a blanket of sediment is critical to the process of fossilization because burial separates the remains from the biological and physical processes that would otherwise destroy them. Why is rapid burial important in the fossilization process because? Rapid burial is important in the fossilization process because: It protect a