Rock Slide near Tuasan Falls in Camiguin. Very last evening I obtained a message from a pal. He despatched me a quick motion picture clip taken final Saturday – April 23, 2016. The title of the concept was: Prophet!
You might remember my posts “Concrete Insanity in Camiguin” from May well 12, very last calendar year or “Camiguin is loosing virginity” from April 20, this 12 months. Just a week in the past. In particular in the 1st write-up I described the threat of the slope near Tuasan Falls. I then wrote:
This hill will continue sliding and will only prevent when the total hill is down!
Any junior geologist appreciates that most volcanoes aren’t developed of sound rocks. Mount Hibok-Hibok is a stratovolcano created of Hornblende andesite and dacite.
… and now the hill came down all over again!
Do not push up to Tuasan Falls. Large Rock-Fall could take place at any time!
Online video courtesy of Jhunry Omaguing Clima. Many thanks to Martin Geuther for transmitting.
Mount Hibok-Hibok is a stratovolcano
A stratovolcano, also recognized as a composite volcano, is a conical volcano designed up by quite a few layers (strata) of hardened lava, tephra, pumice, and volcanic ash. As opposed to shield volcanoes, stratovolcanoes are characterised by a steep profile and periodic explosive eruptions and effusive eruptions, though some have collapsed craters called calderas. The lava flowing from stratovolcanoes ordinarily cools and hardens prior to spreading far thanks to substantial viscosity. The magma forming this lava is typically felsic, acquiring high-to-intermediate stages of silica (as in rhyolite, dacite, or andesite), with lesser quantities of significantly less-viscous mafic magma. Substantial felsic lava flows are uncommon, but have travelled as much as 15 km (9.3 mi). Stratovolcanoes are occasionally identified as “composite volcanoes” simply because of their composite layered composition built up from sequential outpourings of eruptive resources. They are among the most popular types of volcanoes, in contrast to the considerably less widespread shield volcanoes. (from Wikipedia)
There is no compact or developed rock. These hills are developed of loose levels of rocks, pebbles, sand and ashes. Only vegetation, specially trees, can stabilize this sort of hills and mountains with deep achieving roots. Grass and scrubs keep back major rain. All thes plants have been removed to make a 4 lane freeway.
The worst is to appear
Earlier mentioned huge Rock-Slide occurred following much more than 8 months of drought. Camiguin is deeply dry. What will take place when the initially heavy rains come? The nicely identified tropical rainfalls will 1st clean out the good ashes and sand. This will eliminate the momentary maintain of pebbles and rocks. The rocks will fall! 1 does not want to be a prophet to see this disaster appear.
These landslides and rock-fall will not quit until eventually the complete hill will be down and the street absent! It is virtually impossible to stabilize volcanic hills with engineered rock anchors. On Mount Vesuvius in Italy, the walking path to the crater has to be fixed soon after each and every robust rainfall.
There will be a catastrophe! The road is condemned to loss of life. But there is even a even worse circumstance. If rainfall will very last for numerous weeks, the whole hill will turn into a soapy, creamy mass. This mass will slide. Then it will produce a barrage or dam and keep back the waters of Tuasan river. At the time the stress is high sufficient, the barrage will crack and the total barangay of Mainit will be destroyed by an avalanche of rocks, pebbles and sand.
Is there a remedy?
Sorry, I am recognised to be an optimist, but here all hope is lost. The only constructive answer would value billions of pesos. The feasible solution would consist of two gigantesque construction: The initial just one is an avalanche gallery like in the alps. This gallery is a sort of “on the surface tunnel” that guards the street from any slipping rock. The 2nd development is a dam even more down the river. This dam would maintain back again the rock and mud avalanches menacing Mainit.
Do not go up to Tuasan Falls. If you are an addict of solid feeling, you may well go up to stage where the highway descends toward the parking. From there you see the slope and can depend the amount of falling rocks.