Bird's Nest Lodge Fireplace

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The fireplace is primarily comprised of horizontally layered sandstone. Pieces of conglomerate and breccia are interspersed throughout the fireplace. (Breccia is a form of conglomerate containing angular rock fragments that have not been transported far enough to round off.) The fireplace also contains some very old fossils.

Most sedimentary rocks are formed when eroded bits of older rocks are deposited and then naturally cemented into a cohesive rock. 

Very small particles (clay and silt) are deposited in quiet low-energy areas like lakes or the deep ocean. When they harden into rock, they become shale. Larger particles (sand and pebbles) are deposited in high-energy places like beaches and riverbeds. These harden into sandstone and conglomerate.

Can you find these fossils in the fireplace?


This fossil, known as a nautilus is 500 million years old. It lived before fish evolved and was the largest predator in the ocean. The nautilus is a mollusk with tentacles, like an octopus or squid. However, the nautilus has a shell in which to hide. The shell is also partly gas-filled to control buoyancy, so it can swim easily.


Trilobites were a form of sea arthropod -- a bit like lobsters or shrimp. The group lived from the beginning of the Paleozoic (570 million years ago) until the end (250 million years ago) when they became extinct along with 90% of all sea creatures that had been living at that time.

The first coral reefs were formed about 400 million years ago. Like the trilobites, the group was decimated at the end of the Paleozoic era; however, some corals have survived down to the present day.


Coal is formed from ancient plants that are buried and subjected to heat and pressure for millions of years. Thick mats of plant material accumulated in ancient swamps produced coal seams. This little piece of coal was probably a bit of wood carried along and buried with the sand in an ancient stream.

Bird's Nest Lodge poster