Las Sierras
The types of earthquake in this region and the hazards they present can be entirely different from the coastal areas. However as I'm sure you will see, there are always similar hazards when it comes to earthquakes.
There are a variety of different sources for earthquakes in this region. Firstly this area is still affected by the subduction of the Nazca plate. However the effects of these earthquakes are minimised greatly. Firstly any earthquakes that occurs beneath the Andes have a long way to travel through the hard, crystalline volcanic rock until they reach the surface. As a consequence of this, the earthquakes from this source that hit these areas are usually very deep and have very high attenuation (see entry 3) rates, so they do not pose that much of an issue. Even for any massive earthquakes that strike the coastal regions, the waves produced still need to travel a long distance and through solid rock.
The greatest hazard in this region comes from the complex plate boundary with the mini North Andean plate (see entry 1 for more info). This boundary has created many potentially earthquake producing faults. Although these faults aren't large or can produce particularly large earthquakes (6.5M are usually the largest you would find) they are close to the surface, meaning the surface waves do not lose a lot of energy and can potentially be more damaging than a much larger but deeper earthquake. The majority of these faults are not as well understood as the subduction zone is, so prediction is much harder. Earthquakes from these faults could strike anywhere from Quito to Riobamba (Bell 2016).
Initial Hazards
For these two 'hazard' type sections, I will solely focus on this unusual plate boundary as the subduction type earthquakes will be briefly discussed later on. However most of if not all the initial hazards mentioned for the coastal areas apply here.
The hazards these 'intra-plate' earthquakes create will be much more acute than most of the earthquakes down by the coast. As mentioned the shallow depth of the earthquakes will result in much larger surface waves (Bell 2016). This will destroy many buildings, roads and other parts of the infrastructure that cannot deal with the strong earth movements.
This is a real threat in this region, for example Quito has a complex series of faults these can be seen to be the narrow ridges that run through the city that could trigger a potentially devastating earthquake. Also Quito is based on top of weaker rock than the surrounding volcanic rock, so the wave movement will be amplified if the earthquake comes from one of these faults.
Of course landslides are an obvious hazard in this mountainous, steep sided region. As mentioned in the previous entry, always be aware of potentially hazardous slopes in your area. One factor in these regions that could affect landslides is volcanism. Volcanic activity can weaken the sides of the volcano slopes (eg loose material deposited on the side, lava pushing at the sides of the mountain etc.) or even ash fall from eruptions can produce a weak, loosely packed layer of soil that could come loose.
#Quaketips8
Stick together in any time of crisis. A community is stronger if it works together, and may make any disaster seem just a little better.
The hazards these 'intra-plate' earthquakes create will be much more acute than most of the earthquakes down by the coast. As mentioned the shallow depth of the earthquakes will result in much larger surface waves (Bell 2016). This will destroy many buildings, roads and other parts of the infrastructure that cannot deal with the strong earth movements.
This is a real threat in this region, for example Quito has a complex series of faults these can be seen to be the narrow ridges that run through the city that could trigger a potentially devastating earthquake. Also Quito is based on top of weaker rock than the surrounding volcanic rock, so the wave movement will be amplified if the earthquake comes from one of these faults.
Of course landslides are an obvious hazard in this mountainous, steep sided region. As mentioned in the previous entry, always be aware of potentially hazardous slopes in your area. One factor in these regions that could affect landslides is volcanism. Volcanic activity can weaken the sides of the volcano slopes (eg loose material deposited on the side, lava pushing at the sides of the mountain etc.) or even ash fall from eruptions can produce a weak, loosely packed layer of soil that could come loose.
Secondary Hazards
Although there is no tsunami risk, the hazards are much the same as the coastal regions. The majority of the damage done by these earthquakes will be done within the event, the hazards afterwards mostly come from damage control. There will be lacks in supply for the most simple things such as water, food and medicine. Also if Quito is near (or on) the epicentre the government will need to reestablish itself elsewhere before it can run itself again. There will be emergency protocols in place in case of this so there is nothing to worry about.
#Quaketips8
Stick together in any time of crisis. A community is stronger if it works together, and may make any disaster seem just a little better.
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