Rigby5
Diamond Member
The bubbling they spotted is probably air. Natural gas doesn't "bubble".
Yes it does.
All gases "bubble".
Researchers solve mystery of how gas bubbles form in liquid
MIT researchers have analyzed the way bubbles of air or gas form in a liquid, and found that when confined in a tube, this process is “universal,” meaning that it produces bubbles of uniform size and spacing regardless of the specific conditions.
news.mit.edu