Landforms that are Produced as a Result of Costal Deposition
Deposition is defined as 'the laying down of sediments, produced by
weathering and erosion of landmasses…'. Deposition occurs when
velocity decreases and therefore suspended sediment can no longer be
transported. There are four main landforms that are resulting form
landforms, beaches, spits and tombolos, forelands and barrier islands.
The area that I have studied is the Vale of Glamorgan Coastline form
Merthyr Mawr Warren to Breaksea Point and within this area there are
many depositional features. Most of the rock in the area was formed
during the Jurassic period approximately 150 million years ago. Most
of the rock formed in this period was limestone and shale. Lias is the
most commonly found shale in this area, a soft, reddish coloured rock.
Beaches are the most common of the four depositional features. They
are created by deposited material from breaking waves; the
constructive action is mainly effected by the swash. The swash is the
turbulent mass of water, which flows up the beach following the
breaking of a wave. The swash contains much of the suspended sediment,
and this sediment is then deposited upon the beach.
In the area that I have studied there are many sandy beaches and two
good examples of this are Dunraven Bay, and Traeth Mawr Beach. Both of
these beaches have headland on either side, and therefore can be
attributed to refraction. The erosion of these headlands reduces the
energy of the approaching waves, which also supplies a great amount of
eroded material. This then affects the energy of the wave as they
approach the beach and as a result have a lower velocity and this
leads to the deposition of their load on the beach.
There are also many storm beaches found along this area, for example
at Ogmore and Tresilian Bay. Storm beaches are created during storms
when there are high-energy waves. Large material is thrown high up
onto the beach creating berms. This leads to grading, with the largest
boulders at the furthest point from the sea, and the finer material
Investigation on Coastal Erosion In Porlock Bay Aims ---- Aim 1: To find out if beach material is moved across Porlock Bay by longshore drift. Aim 2: To find out which type of sea defense is best for Porlock bay. If L.S.D. (long shore drift) were taking place I would expect to find: a) Deposition at one end of the bay and against any abstractions such as groynes. b)
Lithologically the Kimmeridge Clay Formation can be subdivided into four units (Figure 2), despite of beds at the base of the succession are poorly exposed. However, in contrast, the units from mid-eudoxus Zone to the top of the formation that are well seen in the Formation. At the base of the formation until the eudoxus Zone, the strata are made up almost entirely of bioturbated shelly clays and in between beds, horizons of oil and bituminous are present. The upper part of the Eudoxus Zone until the upper Pectinatus Zone the composition is kerogen-rich mudstones and coccolith limestone.
Yes this feature is the result of erosion and depositional processes however, it is not associated with the current water course. This feature may be the result of a Gilbert type delta that once occupied this area. Gilbert type deltas have three main components; topsets, foresets and bottomsets. Topsets are fluvial sediments (primarily sandur deposits) that were deposited on the subaerial delta surface. Erosive events occurring on the upper forslope can result in downslope channels and chutes. These features are then eroded by either strong currents or by debris flow resulting in these channels and chutes to become filled. Foresets are a combination of sand and gravel facies. The are deposited by gravitational processes on the delta foreslope and the grains tend to become finer and more angular downslope. Bottomsets consist of fine grained silts and clay and are deposited at the foot of the delta front.
Investigating the Geographical Processes that are Affecting the Physical and Built Coastal Environment There are three geographical processes that are affecting the physical and built coastal environment, they are; erosion, deposition, and transportation. Erosion is the group of natural processes, including weathering, dissolution, abrasion, corrosion, and transportation, by which material is worn away from the earth’s surface, this is mainly caused by wind, running water, and waves breaking on the coast. Deposition is the depositing something or the laying down of matter by a natural process. Transportation is when sand is moved along the coast by long shore drift. At North Cronulla beach erosion is evident.
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.
Brimbank Park consists mainly of sedimentary rock, due to its close proximity to the Maribyrnong River. Along the banks, alluvial deposits and terrace sediments arise from the Quaternary Period (Geological map of Victoria, 1973). Although there is a distinct lack of igneous rock in area, the sediments from primary igneous rock upstream have weathered and been carried downstream onto the river banks. This process has been accelerated due to the water in the ecosystem.
...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.
Tarbuck E., Lutgens F., Tasa D., 2014, An Introduction to Physical Geology, 5th Ed, Pearson Education, Upper Saddle River, New Jersey.
Soon after the sea reached longer distance westward and the sandy tidal deposits were converted to deep water deposits. Mancos Shale is the name given to represent these deposits, which are comprised of organic material and small particulates. Another interesting fact to note is that this type of sediment consists of fossils. These remains can include prehistoric shell fish, shark teeth, and many other types of organisms. The hills seen at the foundation of the mesa in the Montezuma Valley are comprised of gray
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.
and Metamorphic rocks can be found. There are also a lot of crusted plates, and violent
During the Late Cretaceous a period of mountain building occurred along the west coast of North America. This is called the Laramide orogeny that started the Rocky Mountains growth about seventy-five million years ago. The Laramide orogeny was different from orogenies that had happened before hand. What caused the Laramide Orogeny is uncertain but there are many theories about what caused it. One big thing to better understand the Laramide orogeny is the theory of Uniformitarianism.
Explain how the slab component is generated in island arc igneous rocks. Consider both the fore-arc and back-arc basin environments
This paper introduces the environmental concerns of the loss of coastal wetlands. The paper will discuss the significance of wetlands and the devastation that is occurring because of human activity. Wetlands are an essential element of our environment both ecological and societal; conservation will be essential for the preservation of these precious ecosystems.
Coral reefs are limestone ridges built by tiny, coral animals called coral polyps. These reefs form when a single, free-swimming coral larva attaches itself to a rock or another f...