Friday, May 29, 2015


 

Indonesia lies on the ring of fire, and is in one of the most geologically active areas in the world. It is very frequent to earthquakes, tsunamis, and volcanic eruptions. This is because the ring of fire is tectonically active and is home to 90% of the world’s earthquakes and dormant and active volcanoes. The plates, (which are the Pacific Plate, Australian Plate, Philippine Plate, and Eurasian Plate) all come together where Indonesia lies and causes pull apart and converging movement. This means that there are four tectonic plates underneath Indonesia constantly changing the geological landscape, causing natural disruptions in between. These plates are constantly sliding past each other causing friction. The volcanoes of Indonesia are mainly the most active in the world. The subducting Eurasian plate and pacific plate is what forms these volcanoes. The converging plates with subduction cause volcanoes and earthquakes. Earthquakes are also caused by the tectonic movement. The Indian Oceanic plate is being subducted under the Eurasian plate because the continental crust is less dense than oceanic crust. It is also interesting that a geologic fault line runs the length of Sumatra, The earthquakes here are mostly caused by the converging Australian plate.
 

Mount Merapi of Indonesia

If I could prevent one of these natural disasters, it would be hard to choose because each one can affect thousands of lives and are many times extremely devastating to the natural environment also. Although, if I could I would prevent volcanic eruptions. Volcanoes cause many different outcomes to the land of Indonesia, and many times they affect neighboring countries. Indonesia has been home to some of the most devastating volcanic eruptions in recorded history. The eruption of Mount Tambora was the most violent of all history, causing widespread agricultural failures throughout Europe and the Eastern United States/Canada. This just goes to show how these eruptions can physically affect many other countries in the world. The most active volcanoes are Kelud and Mount Merapi of Java Island. Mount Merapi is a stratovolcano which has erupted more than 80 times since AD 1000. In 2010 an explosion killed 320 and misplaced 300,000 or more people. Kelud has erupted 30 times in the same time frame, with the most recent explosion occurring in April 2013.
My recommendations for these issues is to have information more readily available to the public, and have training sessions for villagers to give them better tools to be prepared when an explosion does occur. There should also be a fund set aside mainly for aftercare of an explosion. These things would include water, food, and proper things to help with breathing (since the air will be highly toxic.) The most risky areas would probably be those the closest to the volcano, where many times people work to harvest crops that grow near volcanic slopes. These areas of course would need to be cared for before the rest. Although, the Natural Disaster Mitigation Agency has set boundaries around many volcanoes, where nobody is permitted to venture into or live. There are also evacuation routes readily available for many volcanoes. If I had to live in Indonesia, I would try to set up camp as far away from the nearest volcano as possible, which might be hard because there are a LOT of them. I would try to keep myself also on lower ground, since it would take longer for the magma flows to reach me.

 

Sources:


 


 

3.     Keller/ DeVicchio, Natural Hazards textbook.

Saturday, May 2, 2015

Coastal Hazards of Indonesia

Indonesia is surrounded by water on all sides, so of course they  are prone to extreme coastal hazards. The shoreline is not just affected by the erosion and subsidence against the shoreline, but also by the tsunamis, earthquakes and weather changes which affects the relative sea level. Erosion along the coast affects seaside homes and buildings. Central Java and Tegal and especially prone to this erosion because the of their sea cliffs and coastal structure.

Google Images
 
The combined shoreline of Indonesia is approximately 80,000 Km. That's a lot of coastline. The water level is constantly changing because of the amount of tectonic movement and the heightened tidal activity. The long shore movement of sediment also contributes to erosion of Indonesia's landscape. The government in Indonesia has taken some measures to prevent coastal erosion, by implementing seawalls and beach groins were it is necessary, but these structures are not in all areas, so home and buildings are still suffering from these coastal areas. Indonesia is a popular place to visit from tourists, especially Jakarta and Java. The coastline needs to be protected to keep the coast a thriving place for tourists and locals alike to enjoy the beauty of the land.
 
 
 
Sources:
 
 
 

Sunday, April 26, 2015

Indonesia has a variable climate, with mostly tropical weather. The humidity of the Island is quite high, with always a high level of humidity. The areas can have extreme levels of rainfall during the months form September to November. Indonesia has frequent tropical storms (like monsoons) because of the wet climate and high temperature. The monsoonal seasons are there because the Island goes through dry and wet times during the year.

Typhoons which hit the Islands can cause extreme winds and heavy rainfall. The western and Northern parts of Indonesia experience the most rainfall since the monsoons are very heavy with moisture by the time they reach these areas.

Although, Indonesia experiences these rapid changes in climate and weather, but typhoons are not always devasting, sometimes they are only on a small scale and few in between. The only recommendations that can really be made is wear proper clothing and keep umbrellas for sudden outbursts of rainfall.


http://thejakartaglobe.beritasatu.com/archive/super-extreme-weather-is-the-worst-on-record/

http://www.weatheronline.co.uk/reports/climate/Indonesia.htm

Sunday, April 19, 2015

Sinkholes and Soil Subsidence

Sinkholes can be a major problem where the ground underneath contains weak rock such as limestone and salt beds. These types of rock are easily dissolved by groundwater. Sinkholes are dangerous because the groundwater will erode the rock and create spaces which will not show above ground until the spaces are too big, and the ground will suddenly collapse.

 Source: Indonesia.Net
 
 
 
In Indonesia, there are sinkholes and large amounts of soil subsidence. Jakarta has an alarming rate of it's coastal soil subsidence at about 20 cm per year. A lot of the causes of sinkholes in Indonesia are man-made from the extreme extraction of groundwater. The ground does not have time to replenish itself in time for the rock to not sink. Larger areas such as Sumatra and Java do have emergency steps, but only to stay away from sinkholes in the case that one is created. The main problems are that the land is being heavily used for farming that the land is not meant for.
 
 
Sources:
 
 




Friday, April 10, 2015

Mass Wasting in Indonesia

The deterioration of hillsides and downhill movement are all considered mass wasting. This phenenomen can occur at a rapid rate, or can occur extremely slowly. Landslides can destroy communities and take lives.


In Indonesia, there are many earthquake occurences, which will move the earth material. There are also volcanic eruptions and tsunamis which devastate the land, which in turn all these geologic disasters shape the land, especially it's hills and slopes. In Indonesia, many landslides are devastating people and their homes. In December of 2014, a massive landslide in Central Java buried a village and killed 70 people. According the Indonesian Natural Disaster Authority, landslides claimed 248 lives due to landslides in the last year alone.
Google Images


A reason for so many landslides is that the population continues to increase, resulting in changes of land use, deforestation, and the addition of more roads. The soil cannot keep up with these changes, causing a loosening in the soil, and the heavy rainfall doesn't help either.


The Indonesian Natural Disaster Authority believes that that constant changing of substidence crops and change of land use is what is the main  cause of the landslides. Although, the prevention of these disasters seem to have a low priority, since Indonesia suffers from Volcanic eruptions, tsunamis, and earthquakes. Many people who live near these high risk hills and slopes are not eager to leave their homes, so many people will remain near these places until and really bad landslide hits.

Sources:

http://www.asianscientist.com/2015/01/features/landslides-indonesias-worst-nightmare/

http://blogs.agu.org/landslideblog/?s=indonesia+landslides&mswhere=blog&submit.x=0&submit.y=0

Monday, March 16, 2015

Tsunami Activity in Indonesia

Google Images
 
Tsunamis destroy lives, landscapes, and alter the people's lifestyle permanently.
 
In 2004, Sumatra was the home to an extremely devastating tsunami disaster. This tidal wave caused more than 200,000 deaths. Indonesia is highly susceptible to tsunamis because of how the tectonic plates are situated. The plate boundaries are constantly shifting and moving on the seafloor, causing disruptions in the level of water on the seafloor. During a earthquake on the seafloor, the tectonic plate will uplift, causing a hortizontal reaction bringing water toward the shore.
 
 
Google Images

 
 
It is very hard to predict when a tsunami will occur, but the National Tsunami Association recommends that when the ground is shaking, relocate to higher ground. Also, when sea life is exposed, (like fish) that is when a tsunami is going to hit.
 
 
 
 
 
 
 
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Friday, March 6, 2015

Volcano Week!

Indonesia's is a volcanic hotspot due to it's geographical location on the four subducting tectonic plates , which is part of the Pacific Ring of Fire. The main volcano type present here  is a stratavolcano. This type of volcano has steeper sides, and spews out low viscosity magma, toxic gages, and rhyolite rock into the air, and billows up into a large toxic cloud.

Source: Kenrick95
Above is an example of a stratavolcano in Indonesia, notice how steep the sides of the volcano are.
 
Some of the most catastrophic explosions took place on islands in Indonesia. In 1815, Mount Tambora erupted in violent events which was one of the most extreme eruptions in recorded history. As the ash was spewed into the air, the average world temperature dropped about 3 degrees.
 
 
 
There are 76 active volcanoes currently in Indonesia, although there is not enough technology to state exactly when a volcano erupts, there is always preparation. Each province has their own preparedness agency, although their readiness varies. In February alone, two volcanic eruptions left about 130,000 displaced, and many dead. The National Disaster Preparedness agency works with local community governments to plan out risk mapping, identifying threats, and training officials to be ready for these disasters also.
 
 
 
Sources
 
Extremescience.com
 
Volcanodiscovery.come/Indonesia
 
 


Friday, February 27, 2015

Indonesia and Earthquake Activity

Indonesia has a very high seismic activity because of the way that it's tectonic plates are situated, four plates constantly going through friction with each other.  The tectonic region of Java is the most unstable. The island is adjacent to a deep sea trench, and is located where tectonic plates meet. Indonesia's most recent earthquake was a 5.3 magnitude just this Wednesday morning. When looking at the map of Indonesia, you can see that where the subduction zone is, that is where there is high seismic activity and volcanoes.
http://www.shipdetective.com/advice/safety/eq_indonesia.htm

Indonesia is also at high risk for Tsunamis, because earthquakes happen along the seafloor, causing the ocean water to rise up and generate devastating power onto the land.

Google Images
 
 

How Indonesia is Prepared for Disaster
 
You cannot predict when a tsunami, or major earthquake hits, but when one does there is always disaster relief. The American Red Cross plays a major role in aiding people after these catastrophes. They provide food, shelter, and vital medical care to Indonesia's citizens. The Asia Disaster Preparedness Center also helps with Indonesia's recovery. 
 

Saturday, February 21, 2015

       The Indonesian Islands lie where the Pacific Plate, Austrailian plate, Eurasian and the Phillipine plate meet. This is a very unique spot because when different tectonic plates are sliding past each other and causing friction, it causes volcanoes and seismically large earthquakes. This means that the Indonesian islands are hitting 4 plate boundaries, which causes great motion and change to the geologic landscape of the seafloor. The plates would be called convergent plate boundaries with subduction. The Indian Oceanic plate is being subducted under the Eurasian plate because the continental crust is less dense than oceanic crust. It is also interesting that a geologic fault line runs the length of Sumatra, The earthquakes here are mostly caused by the converging Australian plate.

How do subducting plates cause volcanoes? As the plate is being subducted, magma from beneath the surface of the earth is being melted from the friction of the tectonic plates. It  reaches the surface, forming a margin within the oceanic crust, forming a volcano.

Source:http://en.wikipedia.org/wiki/Mount_Talang#mediaviewer/File:Mount_Talang.JPG

Mount Talang is an active stratovolcano in Sumatra. It's most recent eruption occurred in 2004.

Sources:
http://earthguide.ucsd.edu/eoc/teachers/t_tectonics/p_map_plate_layers_bath.html

http://www.livescience.com/43220-subduction-zone-definition.html







Monday, February 16, 2015

Mined Minerals in Indonesia

Indonesia's most mined resources are gold, tin, nickel, copper, and bauxite.
Source: U.S. Library of Congress

Sunday, February 8, 2015

Hazards, Disasters, and Catastrophes.

     A hazard, (in geologic terms) are conditions that are dangerous for humans, animals, and wildlife. Hazards may be occur suddenly, like a volcanic explosion for example. Or, they can be slow forming hazards, such as land erosion near property.


A disaster is the outcome of geologic events which cause loss of life, property damage, cause of fire.. etc. Examples of natural disasters include tsunamis, earthquakes, volcanic eruptions, and cyclones.

A catastrophe is a violent event that affects immense amounts of people, and it also effects the geological landscape. A catastrophe takes years and mass amounts of years to make a full recovery.

A Little bit about Indonesia...

   Indonesia is located in the "Ring of Fire" which is a geographical feature of the ocean floor which creates explosive volcanism. This makes the land of Indonesia highly unstable and there is always the possibility of a volcanic eruption. These volcanoes form because of the contact between the Indo Australian Plate and the Pacific Plate become subducted under the Eurasian Plate, causing the underlying magma to be pushed out and volcanoes to form.