1. Destructive Plate Margins Give examples of some these.
2. Constructive Plate Margins Give examples of some these.
3. Conservative Plate Margins Give examples of some these.
Landforms at Plate Boundaries Fold Mountains and Ocean Trenches When fold mountains are formed various the rock get folded in a variety of ways. These have specific names which you have to learn for the exam. Anticline - the upfolds of folded rock Syncline - the downfolds of folded rock Give examples of some these. What is impact of fold mountains on population sizes?
Case Study 1: Human Activity in Fold Mountain Areas - THE ALPS Low population – physical reasons. Most activity concentrated on valley floors. Range of problems for settlement, transport, etc. Transhumance Farming
Landforms at Plate Boundaries Volcanoes You must be clear about the differences between the two. Shield Volcano At constructive margins. Basic lava (low silicon content). Pours out easy. Low violence, but regular. E.g. Mauno Lao in Hawaii. Composite Volcano At destructive margins. Acid Lava.Greater heat and pressure. Layers of lava and ash. Irregular eruptions. Violent. E.g. Mount Etna in Italy
Landforms at Plate Boundaries Supervolcanoes Yellowstone Yellowstone is fueled by a Hotspot. A hotspot is simply a location at the earths crust where magma from the mantle releases heat and in turn shapes the crust. The Yellowstone Hotspots are the result of approximately 17 eruptions. The most recent eruptions Lava Creek, Mesa Falls, and Huckleberry Ridge occurred approximately 600,000 years, 1.3 million years, and 2.1 million years ago respectively. The devestation has been seen historically to cover half of the USA.
Effects of Volcanoes Try to remember Primary (injuries, buildings destroyed, roads ruined, electricity down) and Secondary (no water or food, disease, rebuilding costs, social breakdown) effects of Volcanoes
Case Study 2: Volcano in MEDC – Mount Etna, Italy (2001) Location and Background Facts Eruption occurred in Sicily an island in Italy in July 2001 Located on a destructive plate boundary between the Eurasian & African plate. Composite cone volcano. Why did it happen? Eurasian plate is subducted under the African plate. Friction causes the crust to melt and this forces it’s way up into the magma chamber. Pressure builds up in the magma chamber and eventually is released as an explosion. This causes gas & steam to escape, volcanic bombs, lava & pyroclastic flows. Social Effects Holiday villas damaged Towns and villages destroyed Eg: Catania People died Environmental Effects Vegetation destroyed Animals killed Economic Effects Orange groves & vineyards wiped out in Zaffarena Roads destroyed so hard to access area Ski areas ruined Farms destroyed & covered in ash Airport forced to close due to ash on the runway.
Case Study 3: Volcano in LEDC – Montserrat (1995 / 1997) Montserrat is a small island in the Caribbean and is a British colony. During this time, Montserrat was devastated by pyroclastic flows. The small population of the island (11,000 people) was evacuated in 1995 to the north of Montserrat as well as to neighbouring islands and the UK. Despite the evacuations, 19 people were killed by the eruptions as a small group of people chose to stay behind to watch over their crops. Volcanic eruptions and lahars have destroyed large areas of Montserrat. The capital, Plymouth, has been covered in layers of ash and mud. Many homes and buildings have been destroyed, including the only hospital, the airport and many roads. There are still some problems attracting investment to the region.