When you think about the structural makeup of archeobacterium (essentially amino acids, and water), it's easy to trace a number of probable causes for their existence. Amino acids bind together in ice to form simple RNA strands under pressure, yet these strands also form in the ocean when lightning strikes and nitrogen and salt are released by the reaction. Should RNA strands group together within ice under pressure, chance occurrences may have causes them to bind together and form more complex RNA, which is the basis of life.
This is the most recent theory, which has demonstrated that ice in our Ice Caps holds carbon, silicon, and a manner of other elements within the primordial ice that constantly combines and deconstructs RNA.
