Characteristics of the physical profile influence its impact Flashcards
Magnitude is a characteristic that influences its impact how does it do this
The magnitude describes the size of physical force of hazard event magnitude is considered the most important factor influencing the impact of tectonic hazard the magnitude of the earthquake can be measured using three different scales
What scales can be used to measure magnitude
The Richter scale based on the amplitude of the wave on seismographs and uses a logarithmic scale from 1 to 9
Moment magnitude scale measures the energy released taking into account factors such as geology area of the vault service and amount of movement from the fault use a scale 1 to 9
McCarley scale a coat of scale that measures intensity based on the effects of the Earth surface
What are some facts about predictability of tectonic hazards
They have an unpredictable nature which influences their impact
The relationship between tectonic hazards on plate boundaries allows the prediction of a location where something will happen but not when it will happen
An accurate prediction can reduce the impact of a hazard by allowing the evacuation of danger zones
Too many in accurate predictions may increase the impact of future hazards as people begin to ignore warnings
How can earthquakes be predicted
Scientists have not yet found characteristic pattern of seismic activity or any other physical chemical or biological change that indicates high probability of an earthquake factors such as increased levels of radon gas and change the water table have all been research but none have been found reliable
What is the seismic gap theory
It suggests that overtime all parts of the fault must attain the same average level of movement this may be through many minor tweaks all the results of a rarer but larger quick
Predictability of volcanoes
There is greater opportunity to predict a volcanic eruption because there are usually warning signs before the main eruption scientists can monitor changes in gas emissions, Ground D formation, hydrology, temperature changes and seismic activity to help with prediction despite the warning signs it still not possible to actually predict when the option will actually occur how large it will be
How can the frequency of tectonic hazards affect the impact
Areas where earthquakes and volcanic eruptions occur frequently magnitude is usually smaller loss resulting in less impact areas with frequent tectonic hazards may have measures in place to reduce the impact such as earthquake resistant buildings in Japan
How duration affect the impact of the tectonic hazard
It can be expected that the longer the event last greatly impact often following earthquakes after shocks can affect places for example Christchurch earthquake in New Zealand 2010
Secondary hazards associated with volcanoes such as Lahars
What is the speed of onset
Speed of onset refers to how quickly the people of the hazard arrives speed of onset of an earthquake is almost instant and having no time to issue warnings and therefore having potentially greater impact however the build up to a volcano slower and can allow for ease of action such as evacuations reducing the impact as many as 20,000 lives have been saved evacuate in the area around mt pinatubo In 1991 due to slow onset of main eruption
How can aerial extends have an impact
The greater the area covered by a tectonic event the greatest potential impact
The impact of an earthquake maybe felt for a few kilometres whereas the impact of gas and national volcanic corruption could be global
