Pray for the Philippines!

My best guess is that the coralline limestone is highly decorative, but that is a guess. Though I recall a religious connection?

I gather that the coralline limestone in Bohol is indeed highly soluble which ties in with the idea that it is easily weakened by rainfall.

It is also notably porous which makes it inherently weak.

Where do you suppose the alkaline source is or what it is?

Come on John...Decorative?
Think structural..
and thats your last clue!

I dont know the reason. I can only guess. It obviously has some feature about it that those who used it felt it was advantageous. But sometimes a substance can be strong or great for one purpose but be weak for another.

Another guess might be that it was easy to carve or work.

But whatever the reason it is obviously particularly soluble in rainwater. That particular limestone is renowned for it.

I just love your little ultimatums.

Surely they didnt choose it because it was resilient to earthquakes?

On the staining and an alkaline source. Are you sure? Staining from any source doesn't equate with the dissolving of said substance.

What kind of industry is there round there? Any of them belching out sulphurous materials?

Erm yes...


Posts 73 and 75 amongst others. And #74 aswell.

http://www.british-filipino.com/sho...-a-Tourist-Paradise/page8&highlight=Januarius

I am sorry to say I have every understanding as I am geologist by degree and profession and I work for an engineering company. I am very used to digging rocks.

And yes, a "broken" chocolate hill. So what exactly are you trying to say? Its "broken" by an earthquake and it crumbled and fell away. Yes, exactly. So what is your point?

Looking at the airport situation and government reports it looks like the limestone there makes both a poor foundation stone and a poor building stone. So what positive qualities does it have?

http://ppp.gov.ph/wp-content/uploads/2011/05/Pangalo-Airport-Final-Report-VolI-Sec6to10.pdf

So tell me, Mr "Boots on the Ground", how close do you need to get to know what rock it is at all? From any vantage point you get, it will be no more informed than mine from half way around the world. I will be curious to know your answer, if you can formulate one.

Evidently Camiguin is formed of volcanic rock mainly andesite and rhyolite. Both used in other knecks of the wood as a building stone.

Why didnt they use it and used the crap coralline limestone instead?

a] because it is "white" and the andesite and rhyolite are not. White reflects light and would be cooler inside on a given day and
b] because with primitive tools the limestone would have been easier to work with.

c] some rhyolites are essentially pumice....likely to get blown away in the wind.



Both Andesite and Basalt blocks side by side using a pointing technique seen in Aberdeen.

Sorry John.. Your Geology degree has let you down on this occasion.
You are not even warm..
I probably will not publish the answer until you are at least partially correct.
Happy Googling!!

From the reports by the government on the airport build, that limestone is problematic both for building and as a foundation. The only other possibility I can think of, structurally, is that the Spaniards used it because it was less brittle than a Camiguin Andesite alternative, thinking it would be more resilient to earthquakes than the Andesite alternative. Though granite is used to good effect in Aberdeen for building.

Limestone blocks are used locally here in houses and an old medieval castle. The blocks are huge but the limestone is just the right kind. It is competent. They arent going anywhere. Structurally they are excellent. Depends a lot on the limestone.

The Spanish use limestone a lot for building. Perhaps they sought it out because they were familiar with it as a building material.

But assuming you havent got it all round your kneck, of course, which will probably be the case. I would never go to a painter and decorator for a geological evaluation. Especially one who reassures me that Bohol enjoys a geohazard free existence and that limestone doesnt get dissolved out by rainwater.

But, hang on, you never got back to me on what you would do that I could not do back here in blighty, with your boots on the ground. So you stomp stomp in your boots on the ground, up to a relic church in Bohol and then what? What next? You look at the mess, the fragments. What is it and how would you know it from a lump of swiss cheese or a piece of concrete? For some reason you are saying it's limestone but how do you know that? Boots on the ground wont tell you everything, especially in your case.

I know somebody who is an expert witness and renowned specialist on metal (steel) failure. (Somebody has to do it). Fatigue, corrosion, you name it. All he needs most times is a good photograph. Thats all I need, not the eyewitness account of a member of the public. There is enough detail in some of the photos to determine quite a lot of info and it contradicts your earlier description of the building material.

The bottom line is this. This seismic event in your own backyard is a wakeup call to those in rose tinted glasses wanting to move to the Philippines. Sure, some areas are evidently low risk, but Bohol isnt one of them.

Have a read of this. It explains simply how and why limestone is vulnerable to rainwater. Notice the specific term "acid" and not "alkali".


http://geology.about.com/od/rocks/ig/sedrockindex/rocpiclimestone.htm

Getting back to your contentious quote above. Of course the ultimate reason was the eartquake. All I was saying was that the buildings were already weakened by mild acids in rainwater. I did not say that the reason they fell down was due solely to acid in rainwater.

I havent seen any yet built in the manner you describe. They appear to be finished off with rectangular shaped cladding. That being the case it isn't providing a structural purpose. Just a cosmetic one.

From boots on the ground:

"The coral stones from the old belfry will be used to clad the new structure." - See more at: http://cebudailynews.ph/news/story/...tored-to-original-beauty#sthash.Mw2RGEV7.dpuf

I'll accept that acid rain may have been a contributor and if it was, then it really only happened within the last 50 years or so and maybe affected the lime mortar binding the individual stones rather than the stones themselves. That said though, there is no heavy industry on Bohol nor (I believe) are there any coal-fired electricity generating stations - whose presence might well be a causal agent.

These buildings have stood for a long, long time (centuries) and have survived other earthquakes as well as considerable damage by the Japanese during World War II. Historically speaking, money tends to flow one way in the Catholic Church - towards the bishops and the Vatican. Very little flows back to maintain its structures which, if it happens at all, is paid for by additional tithes on the faithful. The notable exceptions to this will be the bill for repairing the Sto Nino Basilica and Cebu's cathedral; they are both very important sites, the Basilica is a place of pilgrimage.

Januarius is spot-on regarding the method of construction. These buildings were not constructed using regularly-shaped blocks of limestone of more or less the same size fashioned by stone masons.

You are saying he is spot on but you then say what they are not...hardly spot on. So why do the buildings have very regularly shaped block outlines to the masonry? Check the many photos. Presumably because they are cladding stones only. And underneath the cladding is a pile of rubble?

Rainwater is also naturally acidic. Moreso in the tropics.

"Pure water has a pH of 7.0, this is neutral. Natural, unpolluted rainwater actually has a pH of about 5.6 which makes it acidic. The acidity of rainwater comes from the natural presence of CO2, NO, and SO2 in the lowest layer of the atmosphere (the troposphere)." From Ask Jeeves...but it is well known and well documented. It is something I first learned at school.

Also, dont forget, pollution travels......

Now you are getting warm..
I refuse to respond to your trash talking..Its beneath me!

Yes..Basically the building`s core is made from Anapog rubble.. they actually use large Anapog boulders and then fill in the gaps with the rubble and lime mortar and then clad with 2 inch thick face tile in varying sizes.. There are large wooden beams running horizontally to adjoining "rubble" structures and mortared in.. They used the same timber for lintels etc..
The rubble as you call it is used here these days for infil/backfill etc.. It is mined in places like Cortez and Carmen and is delivered in 14 Cubic trucks.. P4,000 per load.
I just had a quick look at the site (Not the Website ) in Maribojoc but unfortunately the road has a diversion and the church cordoned off so couldnt take any pics..
In short,the lime blocks like the ones used in some historical buildings in the UK are of a completely different grade to the material used here in Bohol..
I know you always want to be right regardless of your glaring ignorance so go ahead..
Have the lastword..
You are welcome to it!! Lol.


OSS.. The church warden assures me that Mother Maria is still standing so I think its safe to assume that the picture was genuine!

No need for any last word. If you look back you will see I mentioned cladding. And you implied there was a structural reason for using coralline limestone which there isnt. I also referred to "grade" of limestone (which is a building term and not a geological term). I think you change your stance and story to suit.

I dont think. I am certain as you have just demonstrated on this thread and others.

Tell me again that Bohol is a low risk region of the Philippines. Oh and you might want to take a look at UK house prices as they havent collapsed like you fervently claimed.

Did you check on the acidity of rainwater and its affect on Limestone? Give it a try...its not too difficult.

Since you set me little puzzles which turn out to be nonsense, here is one for you which is a good one....

With boots on the ground, to coin your phrase, how would you tell the difference between a piece of concrete rubble and a piece of limestone rubble? You are a builder....a photo wouldnt help me.

Actually,its a little unfair of me not to give an answer as to why the Spanish hauled coral stone to Camiguin instead of using those luvverly tough rocks they have over there..
For those genuinely interested... PM me.

It will be colour as Andesite and Rhyolite are darker and also for ornamentation as coral limestone when polished would be highly decorative. This is quite commonly done. White limestone would be cooler to be inside. I gather there might be a religious reason too....

Bohol is an exporter of limestone and probably for that very reason. In fact it is the islands biggest export. No rocket science there.

At least God answers builders prayers for more work

Test result: F-

I dont give a f.

How about you? You know how to tell the difference between limestone, concrete and a lump of swiss cheese with boots on the ground?

OO err..
A nice little after shock there!!
After a while you start to miss em!!

Cebu Daily News http://cdn.ph/news_d...ls.php?id=18492

Humanitarian flights land in Cebu 10/19/2013




Two C-130 cargo planes of the Royal Malaysian Air Force carrying relief kits and tents for earthquake survivors in Bohol landed last night at the Benito Ebuen Air Base in Mactan, Cebu, jumpstarting the expected influx of aid from international agencies.
The first aircraft touched down past 5 p.m. and was met at planeside by Philippine Air Force officials led by Major Gen. Romeo Poquiz, commander of the 2nd Air Division. The second plane landed shortly before 6 p.m as PAF personnel unloaded boxes of tents and “family kits” that will be airlifted to Bohol today.
Poquiz said the aircraft were supposed to fly directly to Tagbilaran City from Subang, Malaysia, but had to divert its flight to Cebu.
“The airport in Bohol could no longer accommodate them because Tagbilaran doesn’t have the capability for night flight operations,” he told CDN.
Major Azhar B. Abdul Rahman, chief of the Malaysian airlift mission, said the relief goods were from the Jakarta-based Asean Coordinating Center for Humanitarian Assistance (AHA Center).
He said they were sent to deliver the relief goods as Malaysia is the Asean-member country in charge of logistics support of the AHA Center.
Poquiz said the 4x4 meter tent can house a family of five. Each beneficiary-family will be given kits that contain sanitary pads, hand towels, combs, detergent powder, toothpaste, toothbrush, soap, mosquito nets, jerry cans, kitchen set, plastic buckets, kitchen knife, wooden scoop, blanket, candles, sarong, floor mat, rubber slippers, T-shirts and an FM transistor radio.
Maj. Mardiana Razali, pilot of the first C-130 plane that landed, said they will fly back to Malaysia as soon as the relief goods get unloaded.
“I am happy and feel appreciated that at least we can help our fellowmen who are really in need of help because of the earthquake,” she said.
Meanwhile, the United Nations’ World Food Programme (WFP) has “prepositioned stockpiles” of 1,000 metric tons of rice, 15 MT of high-energy biscuits and non-food items, such as generator sets, tents and mobile offices to the disaster areas in Cebu and Bohol, its Office for the Coordination of Human Affairs reported. Spain, New Zealand and Canada sent messages of sympathy and solidarity to the Philippines through their embassies in Manila. In Malacañang, President Aquino’s spokesperson Edwin Lacierda said they welcome international assistance. /Michelle Joy L. Padayhag, Correspondent with an INQUIRER report