Friday, October 11, 2019

Volcanic Environment of Western Victoria

Stretching all the way from Melbourne to Portland, the plain is mostly flat and used widely for agriculture. Dairy farms, livestock, and vineyards are all examples of agriculture types found in the region. Major population centers in the region include Cameroon, Hamilton, Portland and Cola.The explorer Major Mitchell described this place as â€Å"a region more extensive than Great Britain, equally rich in point of soil, and which now lies ready for the plow in many regions, as if specially prepared by the creator for the industrious hands of Englishmen. † Western Victoria volcanic plain is one of the three largest volcanic plains in the world in scale, covering the region between Melbourne and Portland, which is over 15000 km. The signs of volcanic characteristics become apparent while driving west of Gelling, where some farms are littered with basalt.Scattered bluebonnets can be found around the area. Driving further west, walls built with volcanic rocks become more and more common. More than 400 vents of scoria volcanoes, marry volcanoes, imposed volcanoes, shield volcanoes and fissure volcanoes are unevenly distributed in the area, with a few youngest ones in the state such as Met. Napier. Other volcanic features such as stony rises, lava tubes/caves, tumults, lava canals and natural bridges can all be found in this area.The volcanoes are very significant to residents in the local region, as it bring fertile soil for agriculture and opportunities for other industries such as stone cutting or tourism. We can say that the local residents are dependent on the volcanoes. It is also an important volcano plain in Australia, as it is the largest volcanic plain in the entry. Lots of studies are being done in this region every year and some paleontologists come from overseas as well. Therefore even on an international basis the importance of this region cannot be ignored.It is recognized by the United Nation as a Global Cooperage and is the only one in Austral ia. Map Source: Textbook Scoria Volcanoes Scoria volcanoes are also called cinder volcanoes, and they are widely distributed in the western plains of Victoria and also the most common type of volcano in the world. Examples of this volcano in the region are Met. Elephant, Met. Narrator, Mr. Rouses and partly Red Rock. These volcanoes have steep sides, and are often formed by one period of volcanic activity. In the scoria cones, we can already tell from the name that we can find lots of scoria rocks. (Figure 1. ) They are small and red pieces of lava containing lots of vesicles in it. Met Narrator is one of the scoria cones we have visited in the trip. It is located near the small town of Narrator. Being the deepest scoria enclosed crater in the state, its crater is very large in scale, with more than 400 meters wide and 190 meters deep. (Figure 1 . ) Currently this volcano is extinct, and the area around is used for mostly dairy and cattle farming, and a little bit of tourism as well . Before the European settlers came to this region, this mountain is used as a trading place for the Karee Wrong people.Although it is located on private land, the volcano is still considered a part of the Swanking Global Cooperage and is still accessible through the Alan Marshall walking trail developed by the government, taking tourists to the top of the crater. Electric fences are set by the land owner to prevent tourists from entering private egging of the mountain. (Figure 1. 2)The highest point on the crater is about 310 meters above sea level, and the land around the mountain is extremely flat compared to the mountain itself. (Figure 1. 3) Figure 1. 2 Alan Marshall Trail.Photo by David Www Met rouse is another scoria volcano located about 1 km southeast of Pinehurst. It stands about 100 meters tall, and the dominant rock present is scoria and basalt. (Figure 1. 4) It is a extinct volcano as its last eruption occurred about 30000 years ago. A quarry is present at the foot of t he mountain and its main product is scoria. The scoria rocks was used to build roads and some buildings. It was closed in the late ass, simply because they ran out of what they're digging for. It has also been reverberated in the ass and the sign of it being a quarry is disappearing.Figure 1. 4. Some low-grade basalt and scoria in the quarry. Photo by David Www Shield Volcanoes Shield or Lava volcanoes account for about half on the Western Plains of Victoria. Its characteristics include gently sloping sides and a broad summit. (Figure 2. 0) Its formed by lava of low viscosity erupting repeatedly, forming layers of solid lava that lopes gently around the crater. Met. Napier and Met. Cottrell are all examples of this type of volcano. Lots basalt can be found in shield volcanoes. Figure 2. 0 Met Napier. Photo by David Www Met. Napier (Figure 2. ) is one of the shield volcanoes that we have visited. It is the youngest volcano in the state, which erupted about 7000 years ago, and therefo re considered dormant. It stands 440 meters above sea level and its located in the region about 25 kilometers south of Hamilton. Unlike Met. Narrator, Met Napier is located in public land, thus easily accessible. A scoria cone is present in Met. Napier, therefore scoria rock can be found as well. This is also one of the best-preserved volcanic landscapes in Victoria, as lava flows and caves can be seen clearly. (Figure 2. ) A scenic lookout is now developed at Harmony's Valley, and tourists can now observe the magnificent lava flow. Figure 2. 1, Baud Caves. Photo by David Www Dale Jerkin, a writer, included Met Napier in his book Aboriginal Dreaming Paths and Trading Routes, which reflects the significance of the mountain in the aboriginal community. It is now managed by the state government. Minor roads and tracks are built to take visitors to the summit. The land surrounding the volcano still stays quite rural, and is used for farming. Fissure Volcanoes Fissure volcanoes are forme d when there are long cracks in the surface of the crust.They usually have no central crater at all. Large quantity of lava will erupt through a linear array of volcanic vent distributed along the crack in the crust. Basalt seems to be the most common type of rock present in this type of volcano. Met. Cycles is an example of fissure volcano in the western plains of Victoria. Met. Cycles is located 42 kilometers south of Hamilton, 56 kilometers north west of Port Fairy and about 330 kilometers west of Melbourne. It elevates 178 meters above the sea level. Although its name is not a scoria volcano, the mount itself is a rounded scoria cone.Scoria rocks can be found in the volcano as well. Its previous eruption happened about 8000 years ago; therefore it's also considered a dormant volcano instead of an extinct one. The whole mountain is situated inside a national park, and is very well managed with facilities such as toilets, information boards, picnic tables and etc. (Figure 3. 0) Fi gure 3. 0. Information Center Photo by David Www Walking tracks are built to guide tourists through the park. There are 7 vents in total along the fissure, with a few under Lake Surprise, a popular swimming pool in the summer. (Figure 3. ) Currently this park is used mostly for tourism as a result of it having such magnificent and well-preserved volcanic features, such as vents, lakes, lava canals, natural bridges and etc. (Explained in later section of the report) Victorian aboriginals used to use this environment as their food source as they plant food on the land and trawl fish from the lake. A part of the park used to be a quarry or 50 years, providing scoria rocks for roads. Currently, natural growth of trees has been covering the evidence of a quarry and reconstructing the land into its previous appearance.Figure 3. 2. Lake Surprise. Photo by David Www Mars and Nested Mars Marry volcanoes are the second most common volcano type after scoria volcanoes. They are created when gro und water meets hot magma and produces steam. The pressure will increase in the ground when this process goes on and will last in an explosion. The explosion is usually vigorous and leaves a large hole in the ground. The bottom of the crater is usually lower than the original ground surface; therefore it may turn into a body of water. (Figure 4. ) During an eruption, large quantity of gas, water, ash, rocks and enigmatic material will be blown out of the crater. When the depart falls down back to the surface of Earth, it will solidify and become a volcanic rock called tuff. Examples of this kind of volcano in the Western Victoria Volcanic Plain include Tower Hill, Lake Knots, Lake Bullet Merrier and etc. They are mostly distributed in the southern region of Victoria, as they are spatially associated with the eater table present. Tower Hill is one of the many marry volcanoes in western Victoria and 13 km northwest of Workaholic.It presents itself like a shallow bucket embedded in the ground from an aerial view, as its crater is 4 km wide and 80 meters tall. Both scoria and tuff can be found in the crater. (Figure 4. 1) It is described as â€Å"a stroll among the gigantic ferns of the valley†¦ A ramble among the cones and craters†¦ The winding path at the foot of the basaltic rises close to the lake†¦ Almost tropical reeds rustle in the breeze†¦ Leafy shrubs and trees form delightful bowers and alcoves†¦ Tender motion in suitable company' by George Fenwick in 1858. Figure 4. 1 .Layers of tuff on the edge of the crater. Photo by David Www Indigenous Victorians and early settlers used the land as a source for firewood. It is then declared a national park during the year of 1892 to preserve its unique landforms. It is also the first national park in Australia. The park covers 612 hectares in scale. In the past century, Tower Hill experienced sever whether conditions such as the drought in 1930, and also experienced major changes such as th e vegetation in 1961. It is now very well managed and only used for tourism. Roads are built to take tourists down the crater.Picnic tables with electric BBC, viewing platforms and toilets are all examples of facilities offered in Tower Hill. Information centers are set up and guided tours are available to explain some of the characteristics of the volcano. Parking lots are available for cars. (Figure 4. 2) Figure 4. 2. Toilets, walking tracks and parking lots in Tower Hill. Photo by David Www Animal control is also a major issue in Tower hill. Koalas are brought to Tower Hill by humans, but apparently they have started to over generate and become a threat to he plants present. Figure 4. 3) They then had to be controlled by injecting a device in their body to stop them from breeding. Foxes, cats and rabbits are currently also considered invasive now as they manifested threat to other animals and plants in Tower hill Figure 4. 3. A koala in Tower Hill. Source: http://www. Irresponsib leness. Com/holidays/Victoria/travel-guide/great-ocean- road-wildlife-and-aboriginal-culture Lake Bullet Merrier is another example of a marry volcano located 4 km west of Cameroon. The crater has turned into a large lake about 2 km in diameter. (Figure 4. This volcano did not show significant elevation, however the northeast side of the crater is relatively higher than the rest of the crater rim as a result of prevailing wind. The lake used to be and is still used for fishing, and now it has also developed into a place for water activities such as water skiing. Other Volcanic Features Stony rises Stony rises are uneven surfaces on the ground. They are usually formed when old lava flow cracks on the top, causing the skin on the surface to sag and collapse. They are usually made of basalt and some scoria rocks. Those stones are used by European settlers for building fences and houses.There are not much management done for these stony rises, as they usually don't attract tourists, apa rt from year 1 1 geography students and other researchers. They are Just cleared out of farms for ease in farming. Stony rises are widely distributed in the western region of Victoria. Figure 5. 0 is stony rises around the town of Pinehurst, created by lava flow from Met. Rouse. Figure 5. 0. Story rises near Pinehurst. Photo by David Www Tumulus The word tumulus (Plural form: tumuli) means â€Å"Small hill† in Latin, and they are commonly known as lava blisters. They are a dome shaped half-spheres on the ground.Sometimes their roof will collapse. (Figure 5. 1) It's formed when gases in lava flow gather in a small area near the surface of the ground and they might also explode. We can think of them as â€Å"pimples in the ground†. They can be found in the region 40 km southwest of Hamilton. Figure 5. 1 . A tumulus located west of Met. Napier. Source: Textbook. Lava Tubes and Caves Lava caves and tubes are formed when a lava flow solidifies on the top but the lava below continues to flow. When the lava stops flowing under the solidified top, it empties out the space below the ground and creates the caves and tubes.Baud cave is a bunch of caves and tubes located in the region 20 km south of Hamilton. This landscape has developed into a park and became a part of Met Napier State Park and is managed by the state government. There are handrails built prevent tourist from falling into the caves, and walking tracks to guide tourists to the various caves. Some of the basalt rocks have been taken out of the caves to build infrastructures such as fences by indigenous people and early settlers, but now as it has developed onto a tourist attraction, those activities have stopped.

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