type of rock

attached is a photo of an igneous rock..just want to double check if it is an ANDESITE..thanks

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another photo of the rock formation where the sample was taken

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Difficult to say from these pictures and I'm not an expert. In your second photo I do see some beds/layering and although this points towards sedimentary rocks, it may also be caused through some sort of contact metamorphism. Both wouldn't result in andesite (an extrusive igneous rock) being formed. The first image does look like andesite, or at least an igneous rock, and I therefore find it difficult to identify this rock due to discrepancy between the interpretation of the formation and the sample.

Sorry, can't really help here...

thanks jacobNestor

No problem!

Are you affiliated with a oil and gas company btw?

jacob nestor,
hydropower..we are planning a tunnel line...do you have an experience with seismic..

Avargas,

Sounds interesting! Are you primarily concerned with structural hazard (faults, tectonics) or also with rock properties and fluid mechanics?
I have quite some experience with seismic and have been a petroleum geologist for several years. Never had to work in mountainous regions though; also I was never involved with geotechnical engineering work. Are you using seismic to test the feasibility of your project?

JacobNestor,

Our study right now is assessing if the project is feasible based on desktop survey..the tunnel support i am calculating is based on the geology and of course if a possible fault will pass through a tunnel line based on a topographic map..can you help me determine the possible probable trace of fault lines on this map..thanks

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Well Avargas.....

it's difficult to tell faults from a topographic map and ideally you should do a survey with a geologist. I can not pick out any fault traces from this map, but a quick way to assess these thing from my home is to delve into google Earth. I looked up the location in the Philippines and overlayed the google map satellite imagery attachment 1.

What you might need to consider when zooming out and overlaying the earthquakes that have been recorded over the last couple of years is that you might be above an active fault zone. See attachment 2 and the green line.

Most earthquakes in the area follow a mayor trend and have a strength of around 5. The originated between 15 and 30 km deep and are probably related with some sort of deep rooted fault zone or subduction zone. For now this would be the only thing I can allert you on and you might already know this. Again, this is not my expertise, but I just want to help as I enjoy geology and tackling these problems.

Hope this helped your survey!

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map showing earthquake line active at depth of 15 to 30 km

google map overlay over topography

jacobNestor

Thanks a lot...