Subduction

The New Madrid Fault is the most active seismic area in the United States east of the Rocky Mountains. The fault is located in southeastern Missouri, northeastern Arkansas, western Tennessee, western Kentucky and southern Illinois. Southwestern Indiana and northwestern Mississippi are also close enough to receive significant shaking from large earthquakes. Despite being far away from current plate boundaries, the New Madrid Fault is a dangerous zone because of the active faults that are…

How do scientists known what the center of the earth is? There 4 ways how scientist found out about the center of the earth ( aka inner core and outer core). Answer 1: Geologists hypothesize that the Earth's center is composed of predominantly iron. The outer portion of the center, known as the "outer core", is thought to be liquid iron. While the interior portion of the center, known as the "inner core" is thought to be solid iron. Answer 2: The main evidence for the structure of the Earth…

Geo-Process’s Results Billions of years ago, the earth was not made up of seven continents, as it is today. It was one big landmass called Pangea. Meaning all land. Pangea went under a process called continental drift, founder by Alfred Wegener, which is caused by geo-process. Geo-process results in changes to the earth's surface because of tectonic plates causing mountain building, earthquakes, and volcanos. First off, convergent plates cause many different types of mountains, like the…

On the morning of February 28, 2001 the Pacific Northwest was hit by a 45 second, 6.8 magnitude intraslab earthquake called the Nisqually or “The Ash Wednesday” earthquake. The Nisqually earthquake occurred when the Juan de Fuca plate subducted under the North American plate, this quickly released the built up strain. This was caused by mineral changes as the plate moved farther into the mantle. The Nisqually earthquake hit the southern end of Puget Sound causing damage to the ports of Seattle…

Abstract Porphyry copper deposits are important for economic value and resources. Some of the common metals found in porphyry copper deposits are gold, silver, and molybdenite. Most porphyry copper deposits can be found along the Pacific Rim and formed during the Tertiary and Quaternary periods. Porphyry copper deposits form through a series of subducting tectonic events, having a copper bearing source, and convection of hydrothermal fluids acting on an igneous intrusion. Introduction…

faults and grabens. These geologic features can be found throughout the southern part of the Rio Grande rift. The second rifting phase occurred approximately 20 million years ago, and was triggered by the disappearance of the Farallon plate in the subduction zone (Baldridge, 1989). During this time frame the Farallon plate had completely subducted into the North American plate and the part of the Pacific plate started touching North American plate in a lateral shear motion. Baldridge…

refers to the form or structure, usually conical, produced by accumulations of erupted material. Volcanoes are formed near weak spots on the Earth’s crust and where magma has been stored below. Magma is created when tectonic plates come together at a subduction boundary, one plate…

Studies of past subduction earthquakes are inexact things, based on finding their geologic signs: sudden changes of elevation that drown coastal forests, disturbances in ancient tree rings, buried beds of beach sand washed far inland and so on. Twenty-five years of research has determined that Big Ones affect Cascadia, or large parts of it, every few centuries. Times between events range from 200 to about 1000 years, and the average is around 500 years. The most recent Big One is rather well…

Yosemite National Park was first protected in 1864 and has since been a fascinating landscape that can be observed by people from all over (NPS). The formation of Yosemite Valley has been a natural phenomena for millions of years, formed by some of Earth’s most compelling geological sources. Yosemite has many beautiful granite formations and glacier-carved landscapes that attract everyone from artists to geologists (Huber, 1987). Yosemite Valley was formed by a series of different forces…

Earthquakes occur deep below the surface at locations called hypocenters or focuses (Marshak 350). This is where the fault motion originates causing an earthquake. The Nazca plate subduction zone is an active fault, meaning earthquakes are common and produced more frequently in this region compared to inactive faults, or places where the fault has not slipped in some time. During an earthquake, body waves radiate across the interior…