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.
The St. Peter sandstone lies in an unconformity. It is 250 feet thick, it can be up to 500 feet thick and it fills erosional channels in the underlying strata. Buffalo Rock is an erosional remnant of Ordovician St. Peter Sandstone and overlying Pennsylvanian clastics. Sign for swift, turbulent, and deep water includes gravel bars and erosional features that are 180 feet above the current level of the river and massive cross bedded sand and gravel deposits along the river course.
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.
The site visited on this day was informally known as the Bedrock Knob (NTS grid reference: 120 342). It is in an area where patches of limestone and exposed bedrock are common. The bedrock is part of the Preca...
...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.
The eruptions of Mount Rainier produce lahar mudflows which are similar to pyroclastic flows except they contain more water. These mudflows carry debris of volcanic ash and boulders that produce lava flows and have the consistency of concrete flowing down a mountain (C.M. Riley). Lahars can flow up to 100 kilometers per hour and can extend out to more than 300 kilometers in distance. Because they are hard to predict, give off little warning signs, and move so rapidly through valleys, lahar slides are considered to be one of the most deadly volcanic hazards.
Tarbuck E., Lutgens F., Tasa D., 2014, An Introduction to Physical Geology, 5th Ed, Pearson Education, Upper Saddle River, New Jersey.
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...
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 common extrusive igneous rock, there are a large number of volcanic provinces across Southeast Australia that have been found to contain basaltic lava flows. It is likely that these flows have come from volcanic activity caused by mantle plumes from the mesosphere. A variety of dating methods have been used to date these basaltic rocks, which have been aged from the Jurassic era right up to the late Cenozoic.
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 ...
The interior structure of the earth is made up of crust, the mantle and core (inner core and outer core). Earthquakes occur on the crust. Crust forms the external layer of the earth surface. On the crust, the plate tectonics forces are in charge of causing the abrupt earth movements. Due to the existence of an immense temperature and concurrent pressure difference in the outer layer and inner layer of the earth, convection currents occur at the mantle. This energy results from overwhelming decomposition of radioactive substances contained by the rocks found at the interior of the earth. The developed convection currents lead to movement of lava; cold lava finds its way to the interior of the earth crust, while the molten lava which is generally hot, leaves the interior of the earth to the outside of the earth crust. These kinds of circulations occur at different locations of the earth surface and consequently results in segmentation of the earth due to movement in different directions.
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.