The Redwall limestone and other geological features are indeed evidence of a global flood as opposed to periodic deposition over eons of time in shallow lakes or local flooding events as suggested by secular science.Here;s a couple links with articles on them...
"Evidence 3 Rapidly deposited sediment layers spread across vast areas
"We find rock layers that can be traced all the way across continents—even between continents—and physical features in those strata indicate they were deposited rapidly. For example, the Tapeats Sandstone and Redwall Limestone of Grand Canyon can be traced across the entire United States, up into Canada, and even across the Atlantic Ocean to England. The chalk beds of England (the white cliffs of Dover) can be traced across Europe into the Middle East and are also found in the Midwest of the United States and in Western Australia. Inclined (sloping) layers within the Coconino Sandstone of Grand Canyon are testimony to 10,000 cubic miles of sand being deposited by huge water currents within days."
http://www.answersingenesis.org/get-answers/features/worldwide-flood-evidence
http://www.icr.org/article/were-grand-canyon-limestones-deposited-by-calm-pla/
Carbon 14 dating methods along with radiometric dating of older timescales also have numerous flaws in them and are based on assumptions of equilibrium being met, constant solar influx, the amount of carbon in the biosphere, etc... C14 has a fairly short half-life of around 5730 years and should not be found in measureable amounts in items that are older than 60-80,000 years old....yet we do find evidences of C14 in such things as diamonds, coal, carbonate rocks, natural gas wells, etc... which are conventionally dated to be millions of years old. A number of assumptions goes into dating methods and those could be wrong....indeed they are based on the evidences.
Preserved tissues and DNA have also been found in fossils which shows that they cannot be millions of years old based on known rates of dergadation of those preserved items.
http://www.icr.org/fresh-fossils/
And there is a plausible means for rapid nuclear decay which could have occurred during the Flood event via piezoeletric effects of rocks grinding against each other and something called Z-pinch fusion and plasma effects. The rocks of earth appear to be much older than they because of this rapid decay process.
For further explanation of the process, read Dr Walt Brown's book on his Hydroplate Theory of the Flood event with many other scientific evidences for it. He also discusses the problems with C14 and radiometric dating methods..
http://www.creationscience.com/onlinebook/index.html
"SUMMARY: Powerful electrical activity within earth’s crust produced earth’s radioactivity. As the flood began, stresses in the massive fluttering crust generated huge voltages via the piezoelectric effect. For weeks, this resulted in discharges of electrons within the crust and subterranean water, much like bolts of lightning. These electrical surges squeezed atomic nuclei together temporarily into very unstable, superheavy elements which quickly fissioned and decayed into subatomic particles and new radioisotopes. Each step in this process is demonstrable on a small scale. Calculations and other evidence show that these events happened on a global scale.4"
http://www.creationscience.com/onlinebook/Radioactivity2.html
Also read the previous page on plasma.
A short video explanation by Dr Brown of the Flood event....
http://www.youtube.com/watch?v=7zkrJG4XUeo
A longer explanation by Pastor Kevin Lea...
http://www.youtube.com/watch?v=j2uu8_RB_0s&feature=related