Introduction Weathering occurs through interaction between rocks, soils, and minerals and the Earth’s atmosphere, biosphere, and hydrosphere. Different types of weathering fall under three general categories of weathering: physical, chemical, and biological. Tafoni weathering refers to small cavernous holes and features that is found in granular rock. Typically, these features include smooth concave walls and are adjacent with one another in networks. Tafoni weathering is a subtype of weathering that falls under hydration weathering and ultimately under the larger umbrella category of physical weathering processes. Fundamentally, this particular weathering occurs due to a salt crystal expansion process where salt crystals or deposits …show more content…
Also, the Santa Monica Mountains also undergo Aeolian processes during particularly strong wind activity such as “Santa Ana” wind events. Moreover, our primary focus area was restrained to about a 1-mile hike into the park and reached a large volcanic swimming hole. The swimming hole acted as a boundary, but there are a few observations beyond the swimming hole that also contribute to this weathering process. In a short distance beyond the swimming hole, there is a visible fault line. Within the hike, the first observable evidence of tafoni weathering was about 40 minutes into the hike. Passing a large rock archway, tafoni weathering was evident in the rock face of the archway as well as the side of the mountains beyond this point. In addition to larger mountains, tafoni weathering was also present in smaller hillsides. This particular type of weathering was also evident in the mountains overlooking the swimming hole. The tafoni weathering observed in the mountains around the swimming hole had larger cave-like features than the mountains not directly touching a body of water. Discussion Presently, there are studies conducted to better understand tafoni weathering with several investigations and theoretical models but due to “limited data available on temperature, moisture and salt regimes” it is difficult to
Kangaroo Point Cliffs are one of the most iconic places that highlight Brisbane city’s history along with the Brisbane City Hall and Story Bridge. These cliffs were known by Aborigines even before European settlers arrived in Brisbane. The development around the Kangaroo Point Cliff was started in the 1900s when roads were developed around the cliff. Today, the Kangaroo Point Cliff offers many adventurous activities such as rock climbing, kayaking on the Brisbane River, Segway tours, bike riding around the garden etc. The rocks found on these steep cliffs are known as the ‘Brisbane Tuff’. These unique pink and green stones were also used in building public buildings during the 1820s and 1830s. The very steep feature and gas holes on the cliff plays a significant role in identifying these cliffs a result of a volcanic eruption (Visit Brisbane, 2018). This essay analyses geological formation of Kangaroo Point cliff and the Brisbane tuff which the
The objective of the trip to Blount Springs, Alabama was to observe and gather data on the geological structure of the area. Blount Springs is located in the northern part of Alabama just 33 miles north of Birmingham, and lies on the southernmost part of the Appalachian fold belt. The field work began on the morning of Saturday April, 7th at 8:50am. The weather was cloudy with temperatures in the mid 40’s, and the area was wet from rain the previous night. Our materials included a map of the area, list of formations, a Brunton compass, and a Rite in the Rain field book. The procedure of the field work involved 12 stops at outcrops to gather data, one stop was omitted from the original plans. This data gathered included bedding and joint orientations
The three faults being considered are thought to have influenced the character of some 120,000 square miles. The Big Pine, Garlock, and San Andreas faults are all mutually active, deep, long, and steep and noted as being conjugate shears. In concert, the faults have defined a primary strain pattern of relative east-west extension and north-south shortening of the area of 120,000 square miles. The large region is noted for its deformity, with the source of this being a northeast-southwest counterclockwise compressive couple. The compressive couple was potentially supported through drag as a result of the deep-seated movement of rock material from the Pacific region (Hill & Dibblee, 1953). The interaction of the faults in the San Andreas region since the Jurassic period have served to shape and contour the present geology of the land, while a study of the paleontology of the region likewise requires such knowledge to effectively determine conditions at any given point in time.
The west coast of North America has been tectonically and volcanically active for billions of years. The Sierra Nevada Mountains in eastern California were born of volcanoes, and magma has been erupting in the Long Valley to the east of the mountains for over three million years (Bailey, et. al., 1989). However, the climactic eruption of the region occurred relatively recently in the region's geologic history. About 760,000 years ago, a huge explosion of magma warped the Eastern Sierra into the landscape that exists today. The eruption depleted a massive magma chamber below the earth's surface so that the ceiling of the chamber imploded, forming what is now known as
The rust on an old bike or truck, New Mexico’s Bisti Badlands, and the Wave Rock in Australia. These things were all caused by some sort of weathering. “Weathering is the breaking down or dissolving of minerals on earth's surface"(1). There are two types of weathering. Mechanical weathering and chemical weathering. Mechanical weathering is the process of when a rock is being physically broken down into small fragments. Chemical weathering is when a rock is being broken down by chemical reactions. These chemical reaction dissolves the minerals making up the rock or changes the rock into a new material. Eventually the rock will just crumble and disintegrate.
First of all chemical weathering is when there is rainwater that is able to react with mineral grains in rocks to form new minerals and also soluble salts. This type of reaction would usually occur when the water is slightly acidic. For this reaction to occur it needs water and would occur more rapidly at higher temperatures for example damp and warm climates would be the best for this reaction to occur. Chemical weathering usually happens more often in the spring because this is when it is more humid and hot outside and that is what chemical weathering needs for it to occur and also when it is usually hot or humid there will also be water.
This dissertation is organized into three separate studies (appendices) that I plan to publish in peer-reviewed journals. The first appendix presents a study that establishes a latest Pleistocene age for volcanic eruptions at Zuni Salt Lake. The second appendix evaluates the hypothesis that the late Holocene hydroclimatic history of spring discharge at Cienega Amarilla is driven largely by variations in El Niño frequency and intensity and the resultant variations in winter precipitation. The third appendix examines the nature and timing of fluvial geomorphic change in mid-elevation valley and piedmont areas of the Carrizo Wash watershed and identifies the climatic factors driving this landscape change. Each of these appendices is described in more detail below.
Mesa Verde National Park on the Colorado Plateau contains many geological aspects of interest, including its sedimentary rock layers, its canyons, its alcoves utilized by ancient people and how these alcoves were formed. Mesa Verde National Park is located in the southwest corner of Colorado, close to the Four Corners area, on top of a high mesa overlooking the Mancos River (Harris et al. 2004). The park, covering 81 square miles, consists of several main sedimentary formations that are characteristic to the park (Encyclopedia Britannica 2015). Canyons are carved into the sedimentary rock, with the cave dwellings found high on their steep walls. These dwellings are an especially unique aspect to the Mesa Verde National Park, and are built out of large alcoves. The alcoves were produced by weathering and erosion of the sedimentary rock type. To better understand how these alcoves formed, we must understand the geology of Mesa Verde National Park and how it has developed over history.
The Grand Canyon has plenty of volcanic rocks near the bottom and the top. ICR, Institute for Creative Research, has been involved in a project for years to date these volcanic rocks. this study has come a long way to show that many of the Grand Canyon strata could have formed rapidly, and that the erosion of the Canyon by the Colorado River has not been going on for millions of years.
- Tephra deposit; felt thousands of miles away and many feet deep in close proximity to the volcano
There could also be chemical and mechanical processes. Mechanical weathering actually breaks the rock, when the cracks form the water can get into the rock and break it more. Chemical weathering will only decay the rock overtime and is not as fast. Erosion can help in a few ways, but generally, it is very negative. Moved soil can be great for planting crops. A negative is that eventually erosion will erode some of Earth’s greatest natural
The author of this article is Beth Geiger, who is a geologist and a freelance writer. She has a background in Earth science, and has worked on many articles concerning outdoor adventures, such a 7 year stint as an editor to Canoe & Kayak magazine. The article is a summary of a publication from Geological Society Publications’, and written by Maximillian van Wyk de Vries. He is an undergraduate geology student at the University of Edinburgh in Scotland.
Located just outside of Moab, Utah, the Arches National Park was underwater 300 million years ago. After the seas dried up, they left thousands of feet of salt. Soon, the layers of salt were covered in sand and other sediments. All of the sediments pressed together and formed sedimentary rock. The red rocks were deposited over millions of years to be the way they are now. During those years, erosion has shaped them into what they look like now. Soon, the water flowed through and didn’t give the top rock any support and collapsed. Caused by erosion, the water flowed through narrow cracks and made canyons.
From the physical perspective, the earthquake caused several major landslides, river blocks, flooding and also modified or created new landscapes. These physical changes challenged the community to make a quick adaptation and some major remediation to avoid post-disaster damages. As example, we will analyze the Riñihue Lake, located 60 miles to the east from Valdivia.
The evolution of the Grand Canyon National Park has been one of the marvels of the world to which many researchers had dedicated substantial amount of controversial studies in attempt to accurately estimate the origin of the canyons and caves/gorges ages and Colorado Plateau current attained mean elevation of nearly horizontal sedimentary rocks based on numerous scientific interpretation of new research data without consideration of a slew of prior geologic data sets that confused geologists many generations ago. It is widely believed in the industry that weather element and volcanism during the ice ages (Cenozoic period) raised the amount of water in the Colorado River drainage system which increased the speed of the Colorado river and its active tributaries and its ability to cut through rocks many years ago, steepened the river (tributaries) gradient attributed to the uplift of the Colorado Plateau sitting near at sea level and the great depth of the Grand Canyon (Flowers, 2010). Additionally, increased differential erosion rate billions of years ago, exposed major geologic rock structures by cutting almost all the terraced walls of the current Grand Canyons created in part by volcanic activity that deposited lava and ashes across the area which completely obstructed the Colorado river system.