Sunday, December 9, 2018

Final Blog- Fiji

Daniel Mendoza 
Geology 9 
Prof. Garcia Garcia
9 December 2018
Fiji Final Hazards Report 

   Now that I have scratched the surface on a country I had never previously studied, I feel capable enough to inform (to my best knowledge) the most dangerous hazards in Fiji. Fiji is a beautiful and tropical set of islands but hosts the dangers of tsunamis and earthquakes.

Tsunamis:

   Fiji struggles with tsunamis hitting the coast line rough around the eastern islands of Fiji. The waves come off of the south and east because the country mainly sits atop of the eastern Pacific plate as well as the Indo- Australian plate. Previous data shows 71 percent of the confirmed tsunamis in the world have occurred in the Pacific Ocean and its marginal seas. I believe this hazard is one of the most dangerous in this region because the highly inhabited eastern island of Suva has the Suva Tsunami Hazard Zone. Recommendations for tsunamis that I would present include constant alert on radio and media outlets broadcasting warnings, leaving the low ground to higher safer areas, and the addition of a self-evacuation route. The place I would target help first is the eastern islands primarily the Suva Tsunami Hazard Zone. They are obviously more susceptible and need more aid.

Earthquakes:

List of seven most recent earthquakes according to USG website
   Not only is Fiji threatened by tsunamis, but earthquakes impose just as much of a hazard. I also mention earthquakes as a priority hazard because they also bombard the south and east islands of Fiji like tsunamis. Earthquakes strike this region due to the Pacific and Indo- Australian plate that Fiji stands between. If you noted that, it is similar as tsunamis and that is because earthquakes and tsunamis going hand in hand. A big enough earthquake triggers a tsunami but not every earthquake is large enough to do so. Not to undersize the damage an earthquake alone can do to one of these islands. As far as recommendations go for earthquakes I would advise seeking stable buildings, abandoning or being aware of (common) unsturdy homes/buildings, and enforce evacuation plans for businesses/schools/hospitals/etc. The main target help would go to the south and southeast islands. Mainly but not limited to the islands of Kadavu, Lau, and Levuka.

My "own" home:

Top right is Taveuni Island
   If I were fortunate enough to ever live and have the opportunity to construct a home on Fiji, then that would be astounding. After a semester filled with weekly dives into the country that is Fiji I found the ideal island weeks ago. Taveuni Island is best suited for what I would want to accomplish in a life in Fiji. Taveuni is a more remote island and locals refer to it as the Garden Island. There is a lot of lush green, warm water, secluded beaches, and not a lot of industry. Taveuni is north east of the main islands which means it is one of the safer islands to inhibit. Farming is a big driving force for the economy on the island and opening a family owned farm there would be what I’d do in a life in Fiji.  

Sources: 




Friday, November 16, 2018

Fiji Coastal Hazards

Fiji's coastal erosion has became the latest coastal hazard affecting the Yasawa Islands. The coastal erosion exhibited here though was caused by human error. Many have gone out to blame rising sea levels, however, along the "Long Sandy Beach" humans installed jetties in an attempt to prevent certain coastal processes. Instead what happened was the shift in the coastal current direction as well as motions of sediments turning to the beach caused coastal erosion over a distance of a few tens of meters. Overall the jetties placed created a reversal of the direction of sand transport and coastal current.




Image result for coastal erosion in fiji




I also found that in a particular village in Fiji, coastal erosion has threatened homes and the village over the years. The coastline poses a threat to flood the village when it rains and villagers have found their own solution to prevent this. They alone built a makeshift 3 foot high seawall made of stones without any concrete to hold it down instead of waiting for the back tracked Fiji government to help. The Ra province village planted coconuts trees and coconuts along the seashore that had been starkTo further protect the village’s shoreline they also planted mangroves and officers from the Department of Forests are helping the villagers plant more mangroves.To further protect the seawall, sand bags were placed along the seawall to weaken the waves crashing on to the seawall. The villagers depend on their marine resources for their livelihood. The village is located in the Vatuira seascape. 
Image result for coastal erosion in fiji








sources: 
https://www.scirp.org/journal/PaperInformation.aspx?PaperID=76564
http://fijisun.com.fj/2014/11/29/villagers-fight-coastal-erosion/

Friday, October 26, 2018

Fiji extreme weather

Fiji fortunately is not the worst country when it comes to extreme weather. Though, it still experiences weather conditions that are a tad extreme. For instance big storms.
The storms that affect Fiji may sometimes turn deadly. As storms eventually turn to cyclones (we'll talk about cyclones another time) they can damage homes, flood businesses, and even kill people. Luckily storms are on watch out in Fiji as Meteorological Services alert the people of the country as best as they can. Big storms do not frequent as much as there is good weather in Fiji though. That is the reason the islands create such a good vacation spot. 


Image result for fiji extreme weather


Image result for fiji extreme weather



Sources:

https://www.fijimarinas.com/climate-weather-fiji/
20121213_TC_Evan_IMG_0811.jpg 
https://www.fijitimes.com/weather-watch-heavy-rain-warning-downgraded/

Friday, October 12, 2018

Mass Wasting

Fiji is an area that hosts many rainfall patterns and rough topography which see some earthquakes that may make localized landslides a frequent hazard. As you can see below in the picture, much rain hits the eastern islands yet also affects the middle and western islands as well. Rain causes uneven soil to be pulled down with gravity causing, in some cases deadly, landslides.
Image result for landslides in fiji map
Warning Systems/ Pre-cautions 
I could find no warning systems set up in Fiji currently for landslides. It appears as though they are relying mostly on measures set up for other hazards. For example they have preventative measures and tips for, cyclones, droughts, earthquakes, floods, etc. However, no mass wasting. I would like to think a few tips from Fiji's flood section on their National Disaster Management Office's web page would carry over into mass wasting protocol. I have provided below a picture for the example of the useful tips in the flood section. 

Sources


Friday, September 7, 2018

Fiji Seismicity

Seismicity


Due to the location of Fiji, earthquakes happen to be often but never taken for granted. Earthquakes generally happen on the eastern Pacific plate the Fiji lies on. Though there have been noted earthquakes to happen along the Indo- Australian plate as well, since Fiji is in the middle of both plates. According to the USG website, this week alone there have been 10 earthquakes ranging from a 4.3 magnitude to a 7.9 which hit most recently (9/6/18). Earthquakes and their damage are prominent throughout the area as you may see in the picture below.







Preventative Measures: 


With earthquakes frequently hitting the country, the threat for tsunami's is of seemingly greater importance. Fiji's National Disaster Management Office (FNDM) has set precautions throughout a few primarily and secondary schools. The schools targeted for the drills that the FNDM set up are those along the Suva Tsunami Hazard zone. It just so happens that the 7.9 magnitude quake on 9/6/18 rocked Suva as it was merely 63 mi from the epicenter.
















Sources:
https://earthquake.usgs.gov/earthquakes/eventpage/us2000h9e2#executive 
https://earthquake.usgs.gov/earthquakes/map/
index.phtml
https://www.youtube.com/watch?v=TPlLnH83W18&feature=youtu.be

Friday, August 31, 2018

Tectonic Plates

Fiji is located at the Indo-Australian and the Pacific plate boundary. As a result, Fiji is considered to be on the Pacific ring of fire with countries such as Argentina, Brazil, Guatemala, etc. Due to this feature of two plate boundaries, Fiji finds itself in the midst of two opposite facing subduction zones which lead to the formation of volcanoes and the threat of earthquakes.

Also, Fiji's tectonic history cannot be explained equally but instead into two separate stages. Stage one: 40-28 million years ago is defined by the continuous volcanic island arc system, known as the Vitayaz Arc. The arc was formed by subduction of the Pacific plate under the Indo—Australian plate. Stage two: 28-12 Million years ago was defined by the diagonal north subduction of the Pacific plate under the Indo—Australian plate. Subduction was therefore a particularly shallow angle to the plate boundary. This all essentially means Fiji was caught under a period of increased stress on the tectonic plates which only increased the uplift of volcanic rocks and formations across the islands. 
Image result for two opposite facing subduction zones
This is what the subduction zone Fiji finds itself in is like.













Image result for what kind of tectonic plate is fiji on
As you may see through the map key, Fiji lies in between the Indo-Australian plate and Pacific plate in a subduction zone. 


Sources: 
Link to article: http://www.mrd.gov.fj/images/Brochures/Plate_Tectonic.pdf
Link to first image: https://study.com/academy/lesson/convergent-boundary-definition-facts-examples.html
Link to second image:http://www.mrd.gov.fj/images/Brochures/Plate_Tectonic.pdf

Sunday, August 26, 2018

Hazards, Disasters, and Catastrophes

Hazards:
Hazards are natural events that pose damage and life threat to human life and property. A natural process, such as a volcano, may only become hazardous when people are inhabiting the space in which  the volcano erupts in.
Disasters:
A Disaster is an event that has been deemed hazardous, has a defined area, and has occurred over a limited time span. In order for a disaster to be specified as such, one of four criteria must be met:

  • 10 or more people killed
  • 100 or more people affected
  • Declared state of emergency 
  • International assistance request

10 people killed
100 affected
• Declared state of emergency
• Requested international assistance
10 people killed
Catastrophes: 
Catastrophes are immense disasters that take ample amounts of time, money, and resources to recover. In recent memory hurricane Harvey is an example of such an event.