[colorshapetexture (OP)]

Just to let the admin know I posted this in the plant science section also as I thought it was relevant. I can/will take it down ASAP if this is wrong in the forum.

Now to my Geology gurus.

Have you ever seen this book?

http://www.aoi.com.au/matrix/Nuteeriat.htm [nofollow]

I am a layman just trying to make sense of the plate tectonics hypotheses. 8
Nuteeriat is a totaly different field of sciencetific study yet the same conclusion as the earth growing theory.
My question to you in this forum is...
 With this information. What is your take on tectonics verses growing?
 And do your scientific studies cross info and lead you to findings as David Noels research took him?

The Truth (?) about Continental Drift, Plate Tectonics, the Expanding Earth, and Subduction, and how these truths have been revealed by a study of the Distributions of Nut Trees and other Plants.


http://www.aoi.com.au/matrix/Nuteeriat.htm [nofollow]

[evan_au]

Today's commonly-accepted geological theories suggest that our present continents achieved roughly their current shape and size when the Pangea supercontinent broke up, about 300 Million years ago, with continents separating and drifting across the ocean basins, driven by plumes and convection currents in the Earth's mantle. It is assumed that the diameter, volume and mass of the Earth has not changed significantly since that time. See http://en.wikipedia.org/wiki/Supercontinent

As I understand it, the "expanding Earth" theory suggests that the continent edges fit together much more closely if the continents maintain their current area, but they were on the surface of a sphere that had a much smaller diameter, such that the continents covered the entire surface of the Earth. The continents drifted apart because the Earth blew up like a balloon, until now the continents cover only about 29% of the Earth's surface. http://en.wikipedia.org/wiki/Expanding_Earth

From an astronomical perspective, I see some conflicts between these theories:

• For the surface area of the Earth to increase by a factor of about 3.4, the diameter would need to increase by a factor of 1.9, and the volume would need to increase by a factor of 6.4 (volume is proportional to diameter cubed).
• If the Earth's continents were locked together, covering 100% of the Earth's surface, it is hard to see how they could have split apart to reform after the previous hypothesised supercontinents: Pannotia & Rodinia
• If the continents covered the entire surface of the Earth, then the current oceans would have covered all the continents, making it a water world.
• This increase in volume would need to come from:
  
  • Additional material bombarding the Earth from outer space
  • The existing material of the Earth expanding to become much larger
• The Wikipedia article on the Expanding Earth suggests some evidence that the diameter of the Earth has not changed significantly since 400Mya

1. If this extra mass came from outer space:

• You would expect to see major crater impacts on the surface of the Earth, since a volume of matter greater than the mass of the Earth would have to land on the Earth, in the last 300My
• You would expect to see signs of a similar bombardment on the Moon and Mars
• If the additional volume was made of similar material to the current Earth, you would expect the Mass of the Earth to increase by a factor of around 6, and the surface gravity would increase by a factor of around 1.9. This would certainly affect the orbit of the Moon (but it's not clear how you would measure that from the geological record).

2. If this extra volume came from expansion of the Earth's current mass:

• Earth's surface gravity would have decreased by a factor of about 1.9
• Thermal heating can cause expansion, but not this much - and where would the extra heat have come from? Radioactive decay should be gradually slowing down, not speeding up.
• There are some phase changes that can cause expansion (think of water freezing to ice), and there are probably phase changes happening around Earth's iron core. However, under the pressure of Earth's gravity (much higher in the past, according to this scenario), reactions that cause an increase in volume would be thermodynamically less favoured.

So if the increase in Earth's volume did not come from external or internal sources (or some combination), I'm afraid I don't see how it could have happened.

The expanding Earth theory originated in the time before mantle convection was hypothesised. Recent work involving measuring the speed of Earthquake waves through the Earth has started to show the existence of mantle plumes, and with more measurements, we should be able to map out the patterns of convection cells in the mantle - and see if they could be responsible for the observed rates of seafloor movement and continental drift. (Accurate measurements of Earth's gravitational anomalies may also help.)
 
Unfortunately, mapping these plumes will probably require far more seismographs located on the deep sea floor (since sea covers about 70% of the Earth's surface).