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Final Blog

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Australia has a unique range of natural hazards that could pose immediate danger to the country. While tropical cyclones can cause intense rain and wind, which leads to flooding and possible costal erosion. Along with the surrounding tectonic plates to the north along the Indo-Australian Plate. Which has been known to pose the threat of earthquakes and tsunamis. I believe the greatest threat to Australia to be wildfires. Also know as, Bushfires and grassfires  they are common throughout Australia. Grassfires are fast moving, passing in five to ten seconds and smoldering for minutes. They have a low to medium intensity and primarily damage crops, livestock and farming infrastructure, such as fences. Bushfires are generally slower moving but have a higher heat output. This means they pass in two to five minutes, but they can smolder for days. Historically, bushfires have caused loss of life and significant damage to property. While naturally occurring bushfires cannot be averted, their
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Coastal Hazards

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Because of Australia's natural location and geography, the whole country is in a potentially at risk for coastal hazards.  Coastal erosion (or shoreline retreat) is the loss of coastal lands due to the net removal of sediments or bedrock from the shoreline. Coastal erosion can be either a: rapid-onset hazard (occurs very quickly, a period of days to weeks) slow-onset hazard (occurring over many years, or decades to centuries).   Coastal erosion is typically driven by the action of waves and currents, but also by mass wasting processes on slopes, and subsidence (particularly on muddy coasts). Significant episodes of coastal erosion are often associated with extreme weather events (coastal storms, surge and flooding) but also from tsunami, both because the waves and currents tend to have greater intensity and because the associated storm surge or tsunami inundation can allow waves and currents to attack landforms which are normally out of their reach.     Coasta
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Extreme Weather Australia

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Extreme Weather in Australia,  Preparedness according to (http://hardenup.org/prepare-yourself/practical-preparation-advice/your-family/prepare-for-severe-storms.aspx)  What you can do to prepare for severe storm season Be aware of severe storm patterns in your area by signing up to Early Warning Network. You'll receive a free phone call or text from your local emergency authority, if they're part of the Network to alert you of severe weather in your area. Trim trees, remove overhanging branches and clear gutters and down pipes, clear yard of loose materials and rubbish Check your roof is in good repair. Secure loose roof tiles or sheets of iron. Protect sky lights with wire mesh and fit glass windows and doors with shutters or insect screens Prepare a Household Emergency Kit and make sure all family members know where the kit is located Check boats are securely moored, or protected on land The Bureau o
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Mass Wasting Australia

According to the textbook (Natural Hazards 4th edition by Keller/DeVecchio) Mass Wasting, otherwise known as Landslides is a comprehensive  term used for any type of down slope  movement of earth materials. In its more restricted  sense, mass wasting refers to a rapid down slope  movement of rock or soil as a more or less coherent mass.  Types of Landslides: Falling landslide involves rockfall, and is characterized by individual rocks fall through the face of a cliff or other large vertical surfaces.  Sliding landslide is more of the typical landslide, either a slump, soil slip, or rock slide, and is the down slope movement of a large surface area of rock, soil, sand, etc. Flowing landslide is defined as a down slope movement of unconsolidated material in which particles move about and mix within the mass.  Landslides in Australia: Preparation according to  https://www.qld.gov.au/emergency/dealing-disasters/disaster-types/landslides  You can protect yourself, your family
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Introduction to Volcanoes

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Volcanoes or volcanism as stated in our textbook, is closely related to plate tectonics with most volcanoes being located near active plate boundaries. There are 5 different types of volcanoes: Stratovolcano   Lava Dome Shield Volcano Cinder Cone Continental calderas All Volcano eruptions are measured by the Volcanic Explosion Index (VEI). Which is a relative scale that measures different eruptions and can be compared based on quantitative and qualitative observations of explosivity. The scale ranges from 0-8 zero being the lowest. The scale is logarithmic based, which means each interval is a 10x increase in volume of ejected materials.  Australia is home to t he world's longest chain of continental volcanoes which has been discovered stretching for more than 2,000 kilometers  along eastern Australia.  This volcanic chain was created over the past 33 million years, as Australia moved north-northeast over a mantle plume hotspot.  Volcanoes in Australia:   Act
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Chapter 3 Earthquakes

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An Earthquake is defined as a sudden movement of a block of Earth's crust along a geologic fault; the movement releases accumulated strain in the rocks.   A Fault is where earthquakes occur along a plane of weakness in Earth's crust. This seismicity map of Australia shows quakes from 1836-2010 Earthquakes in Australia are caused by horizontal compression producing reverse faults. A reverse fault is a generally steep fracture or fracture system in which the hanging wall has moved up relative to the foot wall in a direction opposite to the direction of the fault dip.  Australia has large earthquakes, but the occur infrequently  Which means Australia has a low seismicity but does not mean weak ground motion. It means that strong earthquake motion happens less often.  The largest earthquake ever recorded in Australia occurred in Tennant Creek, Northern Territory in January 1988 a 6.6 on the richter scale.  Three quakes of greater than magnitude 6 hit
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Chapter 2 Internal Structure of Earth and Plate Tectonics

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Definitions from Natural Hazards 4th edition. Plate Tectonics: process associated with the creation, movement, and destruction of these plates.    Australia is surrounded on all sides by both convergent and divergent boundaries and plates.  Convergent: occur where plates move toward each other. Ocean-Continent where the oceanic plate sinks beneath continental plate Volcanic continental arc is formed (Earthquakes and Volcanic Activity) Great Earthquakes, explosive volcanoes, tsunamis, flooding, mass wasting Divergent: occurs where neighboring parts of plates are moving away from each other. Ocean-Ocean spreading of two plates and molten rock (lava) rises up to fill the gaps.   Divergent zone along the Antarctic Plate to the SW and E. Slight Convergent zone along the SE toward New Zealand.  Mid-Ocean ridge forms, new volcanic lithosphere is created.  Light to moderate earthquakes, nonexplosive volcanic eruptions Convergent zone and the site of
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