Welcome to the Beautiful Boracay Earthcache
This Earthcache aims to show you around some geological sites, as well as teaching about the formation and ecology of Boracay’s famous ‘white beach’ and Crystal Cove. In completing this Earthcache, I hope you not only have learnt something about the island, but have become better educated around not purchasing sand products and taking home coral formations found on the beach. This Earthcache is weather dependent and will not be safe to access of days of bad weather due to safety reasons.
Getting Started
This cache assumes you have made your way to Boracay Island. I won’t be covering the complexities in getting here, however will advise you need to take a boat from Iloilo.
To begin, you will need to find a way to Crystal Cove Island where the first 3 waypoints are. This is approximately 20 minutes boat ride from Boracay main beach, there are flocks of tour operators going there by the hour who will be happy to take you there and offer as a tour guide for a negotiable price. You will further need to pay a small entrance fee of 150 paso once on the island. This fee may change from the time of listing. The final waypoint is on Boracay's main beach. This is relatively easy to access, of no charge. Despite the high numbers of tourists, stealth isn’t required as you are simply inspecting the sand.
Waypoint 1 – Crystal Cove Beach
Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. It is defined by size, being finer than gravel and coarser than silt. Sand can consist of everything, but mainly it is quartz. This is due to the fact, that quartz in the rocks of the earth's crust occurs in large quantities and is also very hard.
Boracay is famous for it’s white sand, which does not heat up in the sun to high degrees. In an essay titled ‘Geological Characteristics of Boracay’, Punonbayan stated ‘The most important geological item in Boracay is the sandy white beach deposits. These are composed of coral fragments derived through wave actions from the reefs that surround Boracay and from the coralline layers that constitute the sand’.
In looking at how these sands are formed, he explained that ‘waves would roll, drag and rub these fragments against each other and ultimately deliver the sand-size fraction to the beach zone. Along the beach zone, further wave action would reduce the size and angularity of coral sands’.
Q1: What is the name of this type of sand?
Q2: Standing at this beach, what do you see and feel on your feet along here that identifies this process described above? What shapes do you see?
Waypoint 2 – Cove 1
Crystal Cove was changed form it’s original name of Tiguatian Island due to the presence of a number of crystals. Crystals is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In nature, crystals are mostly formed from ions which are dissolved in water, as for example in the formation of shells or bone. The external shape of a crystal is determined largely by it’s internal atomic structure.
Take the spiral staircase down into the cave and locate the large crystal which is in plain sight. I recommend taking a photo to help later identify this.
Q3: What is the shape of the crystals on the structure? Cubic, Prismatic or Amorphous?
Q4: Is this structure natural, man made, or both?
Waypoint 3 – Cove 2.
Caves are formed by the dissolution of limestone. Rainwater picks up carbon dioxide from the air and as it percolates through the soil, which turns into a weak acid. This slowly dissolves out the limestone along the joints, bedding planes and fractures, some of which become enlarged enough to form caves. The carbon dioxide comes from decaying organic matter in soil, and also directly from the atmosphere.
You will again need to take a spiral staircase down into this much larger cave, from here you will examine the walls and rear tunnel which has an ‘entry’ sign above it to an adjacent cave.
Q5: Describe the texture of the walls, does this indicate dissolution?
Q6: Examine the tunnel which you are permitted to enter. What is the texture of the floor? Limestone, coral sand, or both?
Waypoint 4 – Boracay Main Beach.
Here we arrive at Boracay main beach after sighting and exploring Crystal Cove Island.
This is the famous ‘white beach’ of Boracay, which is quiet different to the beach on Crystal Cove. As described earlier, these sands are composed of crushed coral. Further to this process, longshore currents induce the deposited sandy materials along the southwestern shores of Boracay to migrate towards the northwest when the prevailing winds are from the southwest and those along the northeastern shores move towards the southeast during the monsoon season.
The point stressed here is the significance of the seasonal movement of the sand particles. Such movement is a natural protection by taming the waves when the winds are strong. Gathering away the sands (souvenirs) or any intervention like erecting structures closer to the beach (local hotels seen today), would not only impede the movement, but have a natural backlash. The white sandy materials along the beach zone of Boracay took sometime to put them where they are right now and would therefore require an equivalent amount of time to replace them. They may not be replenished at all and forever gone if the suppliers, the fringing reefs, were allowed to be exploited and unprotected for lack of appreciation and recognition of the key role they play in maintaining the fragile equilibrium of Boracay’s coastal zone.” (Amores, 2007)
Q7: – How does the beach differ here to Crystal Cove beach?
Q8: – In your own words, why should we not interfere with the naturally placed sand?
Once you complete the EarthCache requirements you can post your find without delay, as per the EarthCache guidelines. You will also need to verify your find by sending me a message and provide your answers to the questions.
I hope you enjoyed this earthcache. Please feel free to add photo's to your log! > 
References
http://www.sandatlas.org/sand-types/
http://www.galleries.com/rocks/limestone.htm
http://anwangaklan.blogspot.com.au/2007/06/geological-characteristics-of-boracay.html