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I have a topic on volcanoes, its how the minerals in lava rock formations vary and I actually have to go to a volcano. Lucky me I live in Hawaii. But I need some constructive critasism here. Not some flames on how stupid my topic is. Thanks! :D

I have a topic on volcanoes, its how the minerals in lava rock formations vary and I actually have to go to a volcano. Lucky me I live in Hawaii. But I need some constructive critasism[/u'] here. Not some flames on how stupid my topic is. Thanks! :D

 

I guess you know Hawaii is an island arc. There is a "hot spot" in the mantle there. As the tectonic plate moves over the hot spot, it burns through the crust, causing a new volcano to form.

 

Here's a good link to "hot spot mantle plumes" from the USGS. Hawaii is only the end of an island arc that becomes the Emperor Seamounts and stretches to the Kamchatka Peninsula in Russia.

 

http://pubs.usgs.gov/publications/text/Hawaiian.html

 

So - you are asking specifically how the minerals in lava rock formations vary...

 

Hawaiian volcanoes produce a kind of lava know as "aa" - http://geology.about.com/library/bl/images/blaa.htm

 

Here's a link about lava types.

http://www-odp.tamu.edu/publications/183_SR/012/012_4.htm

 

To help you understand what it says:

 

Mafic - definition:

http://en.mimi.hu/gis/mafic.html

 

Breccia:

http://www.m-w.com/cgi-bin/dictionary?book=Dictionary&va=breccia ,

 

so "autobrecciated" means sharp fragments of lava embedded in the stuff that cooled slowly and is smoothe.

 

basalt:

http://www.m-w.com/cgi-bin/dictionary?book=Dictionary&va=basalt

 

Unfortunately, the definitions may just confuse you more.

 

Your lavas come from basalt, which are mafic rocks, containing iron and magnesium, that come from deep within the earth. They are therefore, an extrusive igneous rock - meaning that they came to the surface in a hurry.

 

You also have "Pillow lavas" that formed when the lava came out under the water and was cooled very suddenly.

 

Hope this helps.

But I need some constructive critasism[/u'] here. Not some flames on how stupid my topic is. Thanks! :D
If you EVER get flamed in the Homework Help forum, don't hesitate to report the offending post using the little red triangle with the black ! in it at the lower left of the post. The staff fully realises that people stop asking questions if they are being made fun of.

 

I can't guarantee your flaming safety for opinions expressed elsewhere in the forums, but here in Homework Help, bullies will get suspension.

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