re: How do Creationists reconcile discoveries that date back hundreds of millions of years

Both are theories. Both have certain points of viability. Creationism explains why we have an earth, solar system, galaxies. Evolution explains survival of the fittest amongst the creatures.

Recently have seen shows that state that new life forms are being created on the ocean floor near fissures where amino acids are present. Makes me wonder if high volcanic/magma activity present during the earlier eras when the earth atmosphere contained high moisture and amino acids gave rise to the various flora and fauna.

Creationism doesn't explain the earth pre-man very well. Evolution still lacks a missing link; that elusive creature between parent and grandchild where a noted change occurs. Change of feather color, loss of digit, mutation from skin to scale, etc.