1. The Don Valley Brickwork consists of many different layers of geological deposits, allowing us to observe and have a better understanding of how the sediments we see today are formed. The most bottom layer in the Brickworks are from the Georgian Bay Formation, and consists of grey- shale bedrocks. Fossils are often found in this layer and it is estimated that this deposit of sediments is around 445 million years old. Above the bedrocks is a thin layer of grey clay sand and gavels left behind by the Illinoian Glacier. This layer is called the York Till and occurred around 135,000 years ago. The next layer consists of a sandy deposit called the Don Formation, which is formed by the Sangamonian Interglacial Stage. Many plant and animal fossils are found in this layer due to warmer climate around 120,000 years ago. Above it lies the Scarborough Formation, which consist of clay and sand. This sediment likely occurred 115 - 106,000 years ago. The next layer above is the Poetry Road Formation, and consist of sand and gravel. This layer is likely formed during the early Wisconsin glacial substage around 106- 75,000 years ago. Higher is the Sunnybrook Drift which was formed 60 – 75,000 years ago. And on the surface, is the Halton Till, which was left behind by the final push of the Wisconsin Glacier. 2. …show more content…
The Precambrian Shield Rocks found in the Brickworks was formed in an ancient sea more than 1.4 billion years ago. Over many years, the heat and pressure from plate tectonics slowly pushed the land into a mountain chain. During the Ordovician period (around 470- 448 million years ago), the mountain chains This layer of shale and limestone is called the Georgian Bay
Wooden and ragstone blocks were place at the foot of the Twin Towers to protect them. The apron of rocks (revetment) sheltered the cliff foot and face. A small number of wooden groynes were also put on to the beaches on both sides of the Towers to preserve the shingle beach and therefore using the shingle beach as a defence. Then after the devastating floods in 1953, in which North Kent was badly affected, a lot of building of hard defences to minimise the risk of more floods and the damage that is associated with them. A straight concrete sea wall from Reculver to Minnis Bay near Margate, 4.5 kms long, was built.
The Kimmeridge Clay Formation is the penultimate formation of the onshore British Jurrasic Succession. William Smith was the first to document this distinct formation on his map of 1815, and to name as the Oaktree Soil. In 1817, he gave the name Oaktree Clay for the layers of clay between the “Portland Rock” and “Coral Rag and Pisolite” but in 1816 Webster was the first to describe in details the formation and changed to the name now known as kimmeridge Clay Formation after the English village of Kimmeridge on Dorset’s “Jurassic Coast” a place frequently visited by fossil hunters. (Cox and Gallois, 1981).
The Kettleby till is considered to be younger than the main till in the area because it may have been deposited by ice contact stratified drift. Ice contact stratified drift is normally deposited by meltwater in contact and or in close proximity to the ice sheet. Stratification and some sorting do takes place.
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.
More specifically, Trois-Rivieres is located in an area with flat and rolling hills, and fertile soils that play a huge part of Trois-Rivieres’s economy. The formation of the Great Lakes-St Lawrence Lowlands happened during the Paleozoic era. “The Great Lakes-St Lowlands were formed by the effects of glaciation. This is caused the city’s rolling landscape where flat plains are interrupted with glacial hills and deep river valleys. After the glacial period, when a large volume of water melted out from the glaciers, the lakes were large, even larger than they are today. However, the lakes shrank to their present size, and flat plains of sediments remained. These sediments formed excellent soil for farming” (Pandya, n.d). This process left behind a large amount of sediment rock, which was beneficial for the manufacturing industry.
The coastal belt of the Franciscan Complex is composed of the youngest and least deformed units and makes up the western quarter of all Franciscan rocks. The rocks of the coastal belt are composed of arkosic sandstones, andesitic graywackes, and quartzofeldspathic graywackes interbedded with radiolarian chert (turbidite deposits) (Blake and Jones, 1981). These sedimentary rocks suggest a depositional environment of deep-sea fan systems with both oceanic and continental provenance. Parts of the belt show evidence of later metamorphism, principally due to subduction. Low-grade blueschist mineral facies are indicated by the presence of minerals such as laumonite and prehnite-pumpellyite (Blake and Jones, 1981). All rock units show evidence of thrust (imbricate) faulting due to the compressional forces of subduction. Ages of the coastal belt run from as little as 40 Ma (Eocene) to as old as 100 Ma (middle Cretaceous).
This sedimentary rock has hardened over the many years with sand shells, small pebbles, grains of sand and rocks of various sizes. In comparison to our 4.5 billion year old Earth, these sand shells might as well be brand new, when in reality they could be up to 1,000 years old. If the sandstone were to be replaced with calcite it would completely change the subclass of rock, it would then be chemical & organic limestone. The variation in sand stone is due to different rates of deposition and change in patterns of the sediment movement (Mc Knight, p. 384). These tightly compacted varying stones and shells will be weathered away by wind and waves over time and could eventually be reduced to a rock the size of your hand.
Froede, Carl R. “Stone Mountain Georgia: A Creation Geologist's Perspective.” CRS Quartely 31, no. 4 (March 1995): 6.
Quartzite is a non-foliated metamorphic rock. This rock is intrusive and forms when exposed to extreme amounts of heat and pressure. Over a billion years ago, there was an ocean where Kamiak Butte is. This ocean floor was made of sand, as time went on oceans receded and the exposed sand underwent processes that turned it into sandstone – or as we learned in class the process of lithification. Years later, this sandstone would morph into the quartzite that is present now.2
...ified rocks are usually inclined due to the structure folding and faulting because of the Paleozoic rock. (Adams, Butts, 23). Charles Butts states, “In its general relations the Paleozoic area of Alabama falls into the large geographic division of the eastern United States known as the Appalachian Highlands which extends from the Coastal Plain on the east to the Interior Lowlands of the Mississippi Valley region on the west.” (Adams, Butts, 43)
It is well known that glaciation is the cause for how Yosemite looks today, but it is not as well known what happened before the relatively recent glaciation which happened about 15,000 years ago. The geologic history of Yosemite and the surrounding area starts 500 million years ago in the Paleozoic Era when the area was still under the waters of the Pacific Ocean (Beatty). This area had a passive fault, similar to the east coast of the United States today. The mud and silt from the ocean settled in the Yosemite area and eventually became shale, siltstone, and carbonate rocks (United States of America). By the end of the Ordovician Period, the fault changed from a passive to an active fault. The oceanic plate started to subduct under the continental crust and push the shale upward, forming the first mountains in the western United States. At first, these were volcanic islands off the coast. This formation is called the Shoo Fly Complex. T...
The geologic history of the Rocky Mountains has come about as an aggregation of millions of years. Briefly speaking, the formation of the Rockies transpired from hundreds and millions of years of uplift by tectonic plates and millions of years of erosion and ice have helped sculpt the mountains to be what we see today. The majority of the rocks that make up the Rocky Mountains began as simple shale, siltstone, and sandstone accompanied by smaller amounts of volcanic rock which formally built up for approximately 1.8 to 2 billion years in the ancient sea. By 1.7 to 1.6 billion years, these sedimentary rocks got caught in the zone of collision between parts of the earth’s crust and its tectonic plates. The incredible heat at the core of the mountain range then recrystallized the rock into metamorphic rock by the heat and pressure of the collision forces. Eventually, the shale would be transformed into both schist and gneiss. It is believed that granite found in the Rocky Mountain parks came from pre-existing metamorphic rock created shortly after the formation of the earth. Ultimately, the high mountains of the period were slowly eroded away to a flat surface exposing metamorphic rocks and granite. This process occurred around the period of 1,300 to 500 million years ago. This flat surface would become covered with shallow seas and rocks from the Paleozoic period and would be deposited and eventually cover the surface. There is...
Coastal Erosion operates at different rates and different times. Limestone rock is eroded slower than sedimentary rock. The cliff at Muriwai made of sedimentary rock was eroded back to expose 'Fisherman's Rock' - the shore platform which, made of limestone -- tended to erode back slower than the cliff.
They are mostly created under water. Sediment makes up a sedimentary rock with materials such as mud, clay, sand, pebbles, and organisms that once lived. These materials are worn away over years by natural occurrences such as wind, water, rain, and snow. Imagine a road in the winter when it begins breaking apart and withering away. The sediment eventually ends up in one place and layer upon each other. When observing these rocks we get the opportunity to see into the past and understand how the world was like long ago. This is possible by observing the impressions made by different organisms and