Overall I think this is a nice article and it is well written. Great to see people are interested in geology here on steemit! I do have a few remarks though:

You wrote sedimentation occured over Eons and plate tectonics. An article I found that deals with this topic (Geologic origins of danxia and colorful hills of Zhangye and comparison with danxia landform in southern China) suggests the strata was deposited between 140 - 100 Ma, which was during the (Early) Cretaceous Period.

The geological time-scale is divided into the Hadean, Archean, Proterozoic and Phanerozoic Eons. These Eons are divided into eras, which are in turn divided into periods, epochs and ages. What I'm trying to say is that with the word eons you suggest that these layers have been deposited over a very long time, although they were only deposited during a 'short' time in the Cretaceous Period.

Secondly, sedimentation and the tectonics you refer to later in the article (convergence, folding and thrusting), usually don't go hand in hand. Sedimentation occurs usually in basins as a result of extension and thrusting usually results in erosion of sediments. The fact that the layers seem to lie concordant on top of each other suggests they were first deposited horizontally and after that they were tilted.

This brings me to the part where you write "the once horizontal sedimentary layers were folded and thrusted". If you take a look at your second figure you see that the layers all seem to dip in the same direction. If these rocks were folded then the layers would also change dip. My guess is that these rocks were uplifted and tilted and the morphology is formed by weathering, as you explain nicely.

Many different colours usually indicate to lacustrine deposits. Depending on the conditions in the provenance area, rivers can transport anything from gravel to clay particles and therefore could deposit sediments with very differing colours. The paper I mentioned above suggests the colours depend on the redox state of the rock. Large Fe3+ contents result in red colours and large Fe2+ contents usually result in white and black colours. Oxidative conditions usually indicate terrestrial deposits and reductive conditions indicate marine (anoxic) conditions. Hematite is indeed an iron-bearing mineral, but it doesn't oxidize; it is already oxidized. Organic matter found in rocks is usually black, not blueish-greenish-gray. Clays usually give sedimentary rocks these colours.

Furthermore, Diagenesis could play a big role in giving these strata their colours (think of groundwater. It can dissolve elements, transport them and precipitate them elsewhere, giving the strata a different colour. Many of the transition metals have strong vivid colours).

I hope you don't feel attacked by my post. On the contrary, I hope you see it as constructive criticism. I think what you're doing is great and so upvoted you;) Keep it coming!