Once the location of a historically important Iron Age hillfort, now famous for its geological features, Mam Tor is located in the Peak District about 2km north-west of the village of Castleton, Derbyshire. Mam Tor is a text-book example of a landslide with its distinctive features of landslips; it is very famous amongst geologists and scientists. The A625 from Manchester to Sheffield built in 1819 intersects the main part of the landslide twice; it was closed permanently in 1979 due to the repeated movement of the landslide. The landslide is a rotational landslide with a large debris flow at its toe (British Geological Survey, 2014). It should be noted that the name Mam Tor is given to the highest point of the landslip which is situated on top of a sandstone ridge which runs between the southern area called Hope Valley and the northern area called Edale. The geology of the main beds consists mainly of micaceous sandstone in the south with mudstones in the north (Skempton, et al., 1989). The landslide occurred when a section of the Namurian Edale mudstones and the overlying sandstone of Mam Tor collapsed resulting in an 80m high landslide it has been estimated that this event had started between 3000 and 4000 years ago (Arkwright, et al., 2003). The landslide is still active to this day.
The landslide has progressively moved over the last hundreds of years. A number of research papers that contain measurements and trends of the movement of the landslide have been published. Donnelly (2006) provided a comprehensive overview of the movements of the landslide and the surrounding areas, paying particular attention to the effects on the A625. The road began to crack around 1910 with 2.5m of subsidence measured in the January of 1915...
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... negative is the cost. Some equipment required for the monitoring of movement and water levels can be extremely costly in time and money, for example TDR can be expensive and potentially easily damaged by water (Kane & Beck, 2013). Moreover expertise in specific areas of monitoring may need to be hired which can also result in extra expenses. Overall arguably the best methods to use when characterising, monitoring and predicting slips at Mam Tor would be a combination of all three methods. Desk based study information and field based data can be inputted into a computer and used to create detailed GIS maps. The GIS maps can be used effectively to characterise the type of landslide that has or is occurring, in addition to the ongoing monitoring of the slip and the surrounding areas and could potentially help in the prediction of any future movements or further slips.
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).
1. 225 MY : Weathering and erosion of very old folded rocks on an area
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.
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...
Bonnett, Gabrysch R.K. and C.W. "Land Surface Subsidence at Seabrook, TX ." US Geological Survey. Seabrook TX: Water Resources INV, 1975.
Although volcanoes are difficult to predict, geologists have made many efforts in order to caution the people of Orting and other surrounding towns of possible lahar slides. Residents have been made aware of emergency response plans and they know the proper precautions to take in the case of a volcanic activity emergency. Sirens have been put in place by the fire department and governing bodies of surrounding communities to detect volcanic activity and warn the community of possible slides.... ... middle of paper ...
Longshore drift is a process by which sediments are transported from one place to another. When this process occurs, beaches, spits and sandbars are accreted over time. If the process of longshore drift is altered by factors such as stronger winds and stronger currents, beach erosion begins at a faster rate and this may result in many serious problems. The main stakeholders of longshore drift are resort owners. They rely on people to visit their resorts and enjoy the beach. However, if longshore drift erodes t...
Stone Mountain rises in sharp contrast to the surrounding flat, rolling landscape creating a geomorphic monadnock. Geologists appear to have consensus of the volcanic origins and underground formation of t...
"The Great Quake: 1906-2006 / Rising from the Ashes." SFGate. N.p., n.d. Web. 10 May 2014.
Ralph Waldo Emerson once said, “we learn geology the morning after the earthquake.” Fortunately for those living along the San Andreas Fault line in California, there are people behind the scenes, from geologists to city and emergency planners, who have no intention of waiting that long.
Motutara Island (stack) was produced by the formation of two caves on either side of the headland -- forming an arch and the roof slowly erodin...
... although we may never be able to understand exactly what soil failures can occur when a natural disasters take place, as time goes on and testing instruments and materials advance we will hopefully have a better understanding of what we can do to avoid soil failures and come up with a better and more sufficient method of improving the soils structure and strength permanently. While researching the information for this report I feel I have a much better understanding for construction geo-technics and foundations especially regarding the deformation, liquefaction and pile information related to this specific event. I hope to carry the information I have learned from this event into the construction field and apply them towards an authentic project that’s taking place and know that the information, regarding soils, I have given input on will be precise and accurate.
Living in Bangladesh, we have seen quite disastrous mudslides from the past few years. Mudslide is also called a landslide or a land slip. It is a downward mass movement of earth or rock on unstable slopes, including many forms resulting from differences in rock structure, coherence of material involved, degree of slope, amount of included water, extent of natural or artificial undercutting at the base of the slope, relative rate of movement, and relative quantity of material involved. There are numerous facts that can cause a mudslide and there are also numerous effects that it can cause us.
Earthquakes belong to the class of most disastrous natural hazards. They result in unexpected and tremendous earth movements. These movements results from dissemination of an enormous amount of intense energy in form of seismic waves which are detected by use of seismograms. The impact of earthquakes leaves behind several landmarks including: destruction of property, extensive disruption of services like sewer and water lines, loss of life, and causes instability in both economic and social components of the affected nation (Webcache 2).