Polski
At the foot of the Chełm Mountain, there is a closed excavation in the dolomite deposit. This place, previously known mainly to geologists, made famous in 2010 a discovery described in the prestigious magazine "Nature", which changed the views of the scientific world on the circumstances in which the first animals came to land.
It was in this quarry, precisely in the south-eastern part of the excavation, that paleontologists discovered animal tracks from 395 million years ago, imprinted in the mud, when the area of today's Zachełmie was covered by a warm, shallow and drying sea. Which animals left these tracks?
They are tetrapods, the first quadrupeds known to us that walked on the mainland. Importantly, they came ashore from the sea (and not, as previously assumed - from fresh water). The scenes recorded in the scales of Zachełmie took place 395 million years ago. This is 18 million years earlier than the first documented landfall of vertebrates until 2010.
The age of this paleontological find was determined so precisely thanks to the index fossils - the rock-fixed remains of primitive animals that were so short in the history of the earth that on their basis it is possible to very accurately determine the age of the rocks in which they were found.
The plate with tetrapod tracks was taken from Zachełmie and properly secured. Therefore, you will not see here the clues described in "Nature" that changed the course of history. However, it is worth getting to know Zachłmie and the extraordinary history behind this place.
It is worth knowing that already in 1987 a fragment of the northern wall of the quarry was protected. You don't need to have in-depth knowledge of geology to see this clear discrepancy in the arrangement of rock layers. The gray dolomites from about 395 million years ago are inclined at an angle of about 45 degrees. Above these rocks lie almost horizontal red Permian-Triassic rocks, which are about 250-200 million years old.
