I wanted to post these PHOTOS and the VIDEO LECTURE that follows to get this topic onto my site. It is one of the many evidences that throws a monkey wrench into long ages (h-t to Glen B.). FIRST, a definition needs to be applied to “polystrate fossils”…
- The term “polystrate” was coined to describe a fossil which is encased within more than one (poly) layer of rock (strata) thus “polystrate or “many layers.” A wonderful story can be told by these fossils which invalidates the commonly held uniformitarian idea of slow and gradual accumulation of sediments. (ICR)
There are a few arguments against these fossils, like this, this, and this). Enjoy. 
Here is a good lecture explaining well the importance of these fossils:
Video description:
Any fossil that crosses two or more sedimentary layers is called a poly (many) strate (strata) fossil. Polystrate fossils have been discovered all around the world and polystrate fossil trees are quite commonly found in coal mines. Other types of polystrate fossils can be found in various locations and situations of sedimentary strata.
These geological and paleontological evidences are compelling arguments against uniformitarianism and millions of years of earth history. The most plausible alternative explanation to the “deep time” secular view is that these fossils were rapidly buried, a concept that is in line with the biblical creationist view that most of the sedimentary layers of the world were laid down during the Genesis Flood at the time of Noah.
In this PowerPoint presentation by J.D. Mitchell, a number of examples of polystrate fossils will be examined including fossilized trees, complete forests, trace fossils and several kinds of animals. Possible explanations for these types of fossils found in thick as well as thin multi-layers are provided based upon biblical creationist presuppositions.
J.D. Mitchell is a registered professional engineer in Oregon and Washington and has a Bachelor of Science in Mechanical Engineering from the University of Washington. He has also completed his Master of Biblical Studies in Biblical Creation Apologetics from Master’s Graduate School of Divinity.
J.D. is Executive Director of the Institute for Creation Science of Oregon, and speaks and writes regarding the creation versus evolution controversy as a part of his creation science ministry (Creation Engineering Concepts).