The Palisades basalt sill is one of the most active mass movement areas in New Jersey (Pallis, 2009) and because of its activity it is important to understand the underlying mechanisms that cause the rockfalls along the outcrop. The Palisades are composed ancient Jurassic flood basalt that formed through at least three distinct intrusion events (Puffer, 2009). It is important to understand that in all of these events the molten magma was allowed to completely cool before the next event allowing for the formation of the iconic hexagonal columns of basalt (Puffer, 2009). These columns are referred to columnar joints and formed when the molten basalt cooled within the earth's crust. The cooling of the basalt caused it to shrink, creating vertical fractures along the weakest planes of the newly formed rock (Puffer, 2009). These joints are called primary joints due to these columnar joints forming as the rock itself formed (Linsey, 2014).
Studying the effects of weathering and erosion on the uplifted and exposed basalt sill is important to understanding the geological events that lead to mass movements in the area. My researc sought to determine exactly what happens to a rock that has been exposed to natural weathering such as thermal, biological, chemical, and wet-dry also referred to as slaking, on a qualitative and quantitative scale. The weathering of the rocks, though apparent on the exterior of the sample, has an extreme and transformative effect on the internal structure (Gupta et al., 1999). Weathering disrupted the internal crystalline structure by producing microfactures, voids, and the deposition of clay minerals (Gupta et al., 1999). Basalt is heavily affected by weathering when concerning porosity and the formation of ...
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...2006) observations: Geomorphology, v. 99, p. 353-368.
Matsuoka, N., and Sakai, H., 1998, Rockfall activity from an alpine cliff during thawing periods: Geomorphology, v. 28, p. 309-328.
Monthly Average Temperature for New York, NY: http://www.weather.com/weather/wxclimatology/monthly/graph/USNY0996 (March 2014).
Pallis, Ted, 2009, New Jersey Landslides: New Jersey Geological, Information Circular, p. 1-4.
Puffer, J., Block, K., Steiner C., 2009, Transmission of Flood Basalts through a Shallow Crustal Sill and the Correlation of Sill Layers with Extrusive Flows: The Palisades Intrusive System and the Basalts of the Newark Basic, New Jersey, U.S.A.: Journal of Geology, p. 139-155.
Yan, F., Feng, X., Chen, R., Xia K., Jin, C., Dynamic Tensile Failure of the Rock Interface Between Tuff and Basalt: Rock Mechanics and Rock Engineering, May 2012, v. 45, p.
Marshak, S. (2009) Essentials of Geology, 3rd ed. New York: W.W. Norton & Company, ch. 11, p. 298-320.
1. 225 MY : Weathering and erosion of very old folded rocks on an area
The third alluvial deposition consists of sand, silt and minor inter-bedded gravel, and again indicates Brimbank Park’s changing geology over time. (Geological map of Victoria, 1973). These deposits, as well as a nearby fault suggest volcanic activity 5-1.6 million years ago, which explains the olivine basalt (fig. 2) deposits which date back to to the Silurian and Tertiary period.
...e morphed it into the quartzite that is seen surrounding the butte (4). Rocks that undergo this process are called metamorphic rock, which is the same as the rock seen years ago by dinosaurs and other extinct creatures. The quartzite rocks were formerly seafloor sediment that was forced upwards, and then surrounded by lava basalt flows. Once erupted through fissures and floods through out most of the area, lava flow eventually created enough basalt to form a thickness of about 1.8 kilometers (1). All of this basalt flow eventually led to the covering of most mountains, leaving the buttes uncovered. The igneous lava flows and loess is reasons that the Palouse consists of such sprawling hills, and rich soil for farming (2). In result of the lava flows, the Precambrian rock Quartzite was formed. And lastly covered by the glacial loess, which were carried by the wind.
Earthquakes are a natural part of the Earth’s evolution. Scientific evidence leads many geologists to believe that all of the land on Earth was at one point in time connected. Because of plate tectonic movements or earthquakes, continental drift occurred separating the one massive piece of land in to the seven major continents today. Further evidence supports this theory, starting with the Mid-Atlantic ridge, a large mass of plate tectonics, which are increasing the size of the Atlantic Ocean while shrinking the Pacific. Some scientists believe that the major plate moveme...
Tarbuck E., Lutgens F., Tasa D., 2014, An Introduction to Physical Geology, 5th Ed, Pearson Education, Upper Saddle River, New Jersey.
...under H₂O-undersaturated conditions, water was structurally bound up to the greenschist facies and then at the start of anatexis the excess water maximized the amount of H₂O-undersaturated melt generated. Furthermore the dissolution of accessory minerals can provide melts with structural components which in turn give clues about melting history and melting conditions, even during rapid melting. The analysis and mass balance of trace elements found in the glasses and residual phases and melt extraction data, together provided evidence that significant amounts of LILE were retained in residual feldspars and biotite crystals up to a high degree of partial melting of the crustal protolith. This is interpreted as meaning that higher temperatures of partial melting are needed to more efficiently differentiate the crust in these mostly incompatible trace elements.
"Sedimentary Rocks." Backyard Nature with Jim Conrad. N.p., 18 May 2015. Web. 25 Oct. 2015.
One of the best vacation spots and most fun are down the shore in Wildwood, New Jersey. Wildwood consists of a boardwalk with tons of rides and fun, a beach with a beautiful ocean, and little summerhouses with ocean-side views. The best attractions though would probably be located on the boardwalk. There are so many things to see and do. Although it’s rather costly, it’s well worth it and it’s a great place for a family to share quality time together.
Volcanism is a major part of the Galapagos and their formation. The island chain is positioned on the Nazca Plate, which is subducting beneath the South American Plate at a geologically rapid pace of 2.5 inches per year. In addition, this Nazca Plate is located directly on top of the Galapagos Hotspot. It is here that mantle plumes melt Earth’s crust, creating volcanoes as a product. The oldest island was first shaped by this ...
During the late nineteenth century, America was undergoing a cultural change in society. An island with Amusement Parks and vast beaches was underway in development to change the face of America in ways no one could have imagined at the time. The island was referred to as Coney Island. Coney Island Amusement Parks was built in a span of 30 years that would provide the American people a place to relax and enjoy time together with their friends and family. As a whole, Coney Island at the turn of the century, offered the ways of the future in distinctive ways; through technological advances of the era. Around 1900, the Brooklyn Rapid Transit Company created steam railways that connected Manhattan and Brooklyn, thus making Coney Island much more accessible to people living the city (Source 2). Coney Island was a symbol of America in the early twentieth century, where all of America’s values and traditions were defined and brought into one place. In a sense, Coney Island took Americans from the Victorian age, to a more modern and futuristic sense of what America could potentially become. Changing economic and social conditions helped to create the basis of new mass culture that was carried on into the new century (Source 1)
Basalt is a commonly occurring igneous rock. More specifically however, Basalt falls under the category of Mafic Rocks. Mafic rocks have a poor Silica content, approximately 50% (Charles, Diane, Lisa, 2010) and contain high concentrations of metal oxides. Basalt is a fine grained rock containing predominantly ferromagnesian minerals, followed by plagioclase feldspar. The colour of Basalt ranges from dark grey to black and is relatively featureless. See Fig 1.
In the west, the Dakota sandstones are reminiscent of the transgression and regression of the Epicontinental Sea. Tectonic deformations and erosion continued as we see in folded and faulted rocks in the Rocky Mountains. Bentonite, present in that part of North America, proves the active volcanism of the time.
inferred for the reservoir (4). The magma ascent to the surface occurred through a conduit of possibly 70 to 100 m in diameter (5). A thermal model predicts that such a reservoir should contain a core of partially molten magma (6) that can be detected by high-resolution seismic tomography.
Due to the fact that rocks are composed of high intensity of elastic and brittle material, they therefore store considerable amount of strain energy that results from elasticity, during the action of plate tectonic. The brittleness leads to development of concurrent cracks on the rocks as a result of plate’s action.