big picture, please

by Andrea Elizabeth

It is so frustrating to try to find answers for how the earth and life formed when my thick book just quickly glosses over stuff and takes stuff for granted. I have another book that may go into more detail, but right now I’m trying to fill in the blanks by reading articles online. I have not saved these all of these articles but independent google searches of key words should make the latest theories apparent. The problem is that when you start getting into more details, the information becomes much more isolated from the big picture. My big picture query right now has to do with the formation of continents, but that also involves our planet at one time being completely covered by water.

There is a lot of new thinking on lots of things. Used to be they thought that comets brought water to the cooling earth’s crust. That’s always seemed silly to me. Now research shows that comet ice contains too much of the wrong isotope of hydrogen, deuterium. Our water is more consistent with that found on asteroids. Still, talk about trying to fill or empty the oceans with buckets. New research is studying the possibility that the asteroid rocks that formed the earth contained water that precipitated from molten magma. This is still unsatisfactory to me because a lot of earth’s components didn’t arrive pre-packaged. It’s pretty obvious that the earth is basically a smelter. A huge cauldron of all the elements whose dynamic creates different layers of temperatures and their corresponding precipitates.

Unsatisfied with the water capsule in asteroid theory, I separately googled how do you make two hydrogens and one oxygen atom combine? It’s pretty easy but very dangerous. You get the 1st and 3rd most common atoms in the universe together and you light a match. Voila, a huge explosion and water. There are a lot of other ways as well. Some people also say water came out of volcanos – there you go. Some say that water happened before the atmosphere, but I agree with the ones who say it happened at the same time, due to the different weights of the new combinations and the different temperatures they exist in.

Anyway, apparently oxygen does not occur by itself and must bond with something. In the early stages it bonded with carbon and the atmosphere was co2. Methane, which is hydrogen and carbon, probably before that. Everyone agrees that oxygen was released into the atmosphere as an independent gas after algae like organisms covered the water. And they agree that oxygen makes up 50% of the earth’s crust. First there was oxidation of free floating iron that caused it to become insoluble and deposit on the ocean floor in bands. Other rocks also absorb lots of oxygen and carbon gases from the atmosphere.

But the continents were formed mostly from granite (which has more oxygen {1st most comon element in the crust}and silicon {2nd most common}, which combines to form quartz [silica]) which has more of the lighter elements that have floated up as convection of magma differentiated and recycled the elements according to weight over long periods of time. Therefore granite owes a lot of its oxygen content to respirating sea plants!  Granite has larger amounts of silica than basalt, which comes from the magma extrusion in spreading oceanic ridges, does. I have been googling silica, which is the resultant quartz, origination sites and am not totally satisfied yet. It comes from magma and steam vents? It seems silica is the major stabilizer in granite. It is very resistant to weathering and erosion. It is also what makes up sand and sandstone, which is the remaining part of eroded granite.

So, it seems to me that by putting 2 and 2 together, we get continental and plate formation as the lighter elements crystalized, floated up, and moved together. Their places are continually replaced by basaltic ocean floor which is heavier and in the molten cauldron, subducts under the lighter continental crust, which process pushed old sandstone up to the top of the tallest mountains along its fault lines. Intercontinental rifts, such as occur at Yellowstone, Lake Baikal, Ethiopia and the Red Sea are also very interesting and worthy of more study. It seems they occur over hot spots which are poorly understood atypical magma intrusions.

ok, i’m tired. sorry for the number of “which”s