Of course we can't really say how much mass the sky has, but we can get a value for how much energy is necessary to flatten the mountain.
This is Mt. Tamalpais, upon which Atlas is eternally condemned to separate Ouranos and Gaia forever. That is, unless someone takes his place. Should he let go, the mountain and everything within 100 leagues, or 555.6 kilometers, will be flattened.
I figured compressive strength was the most logical thing to use for this calc, based on the verbiage in the quote.
Anyway, Mt. Tam is 747m in prominence.
(747/115)668=4339m
This obviously isn't the entire thing, but I had trouble finding clear pictures of the whole mass.
Gonna calc this as a cone. Now, some of you might be kinda skeptical, but keep in mind that this is like the low-ball of all low-balls, considering everything within a 277.8km radius is also being flattened. That includes many, many Californian cities, as well as other mountains.
vcone=(1/3)pi*r^2*h
v=(1/3)pi*2169.55^2*747
v=3682040377.3m^3
Now, I don't know much about compressive strength, but I took a look at EM's Fantastic Four bit feats, part 6 and saw that he had compressive strength for rock at 200MPa.
1Pa=1N/m^2
3682040377.3 m^3*200000000 N/m^2= 736408075460000000 N*m
1N*m=1Joule
736408075460000000J
This obviously only accounts for Mt. Tam, so I might be doing a bit or research to see what significant masses reside within a 277.8km of the thing to add to this value. In any case, this should be a lot higher.
Edit:
I'll put in a few more mountains which I found to be within the 277.8km radius.
Apparently, this includes Mt. Diablo (eat your heart out, Jason
).
This is Mt. Diablo. The line I drew might seem kinda long, but it does account for the base as well as the peaks behind this tallest one.
Mt. Diablo has a prominence of 949m.
(949/104)1024=9344m
(1/3)pi*4672^2*949=21692045095m^3
21692045095(200000000)=4338409019031559578J
At the other end of the Diablo Mountain Range rests Mt. Hamilton.
(951/153)800=4972.55m
(1/3)pi*2486.275^2*951=6156125446m^3
6156125446(200000000)=1231225089200000000J
If we add all of these values up, we get 6306042183691559578J
or about 1.5 gigatons.
Now that I think about it, I probably should have used elevation instead, seeing as flattening would bring everything to sea-level. Also, Atlas likely meant a 100 league radius which would boost this a lot. Oh well, small-island level it is:distracted
Edit: Okay, well as of HoH we know that primordial gods are unequivocally the things they represent, so...
SA of Earth is 510,072,000 km^2. The radius of our affected area is 277.8 km, so the area would be a bit more than 242445.6 km^2.
http://hypertextbook.com/facts/1999/LouiseLiu.shtml
Mass of the sky seems to be 5.3x10^18kg.
(242445.6/510072000)5.3x10^18=2519177057356608.5kg
PE=mgh
PE=2519177057356608.5(9.8)749
PE=18491263436408977711.7J
or about 4.4 gigatons.
If we take Atlas's instant statement to mean a second...
KE=.5mv^2
KE=(2519177057356608.5*749^2)/2
KE=706630424177057362554.25J
or about 169 gigatons.
