Friday 28 October 2011

Saturday 15 October 2011

Thursday 13 October 2011

ANCIENT ANTACID: MIDDENS


Many First Nations sites were inhabited continually for centuries. The discarded shells and scraps of bone from their food formed enormous mounds called middens. Left over time, these unwanted dinner scraps can transform through a quiet process of preservation. Time and pressure leach the calcium carbonate, CaCO3, from the surrounding marine shells and help “embalm” bone and antler artifacts that would otherwise decay. Calcium carbonate is a chemical compound that shares the typical properties of other carbonates.

CaCO3 is common in rocks and shells and is a useful antacid for those of you with touchy stomachs. In prepping fossil specimens embedded in limestone, it is useful to know that it reacts with stronger acids, releasing carbon dioxide: CaCO3(s) + 2HCl(aq) → CaCl2(aq) + CO2(g) + H2O(l)

For those of you wildly interested in the properties of CaCO3, may also find it interesting to note that calcium carbonate also releases carbon dioxide on when heated to greater than 840°C, to form calcium oxide or quicklime, reaction enthalpy 178 kJ / mole: CaCO3 → CaO + CO2.

Calcium carbonate reacts with water saturated with carbon dioxide to form the soluble calcium bicarbonate. Bone already contains calcium carbonate, as well as calcium phosphate, Ca2, but it is also made of protein, cells and living tissue.

Decaying bone acts as a sort of natural sponge that wicks in the calcium carbonate displaced from the shells. As protein decays inside the bone, it is replaced by the incoming calcium carbonate, making the bone harder and thus more durable.

The shells, beautiful in their own right, make the surrounding soil more alkaline, helping to preserve the bone and turning the dinner scraps into exquisite scientific specimens for future generations.

Sunday 9 October 2011

Friday 7 October 2011

POWELL RIVER

PANGEA: THE GATHERING OF CONTINENTS

Pangea was an ancient continental landmass which formed about 240 million years ago. Had you been around to see the Earth at this time, you would have set your feet on most of the bits and pieces that would go on to become continents we know today. In the Earth's long history, most of the major continental places were gathered into a single mass. Pressure from deep within the Earth let to the break up of Pangea into the two huge landmasses of Gondwana and Laurasia.

Gondwana would split yet again into the modern contents of South America, Africa, India, Australasia and Antarctica. While they are far apart today, we find similar fossils on each of the continents from their shared history.

Thursday 6 October 2011

PLATE TECTONICS & PINOT GRIS

An evening view of Lund Harbour off beautiful British Columbia's rugged west coast is enough to get most folks dreaming of an ocean view. Some 270 million plus years ago, had one wanted to buy waterfront property in what is now British Columbia, you’d be looking somewhere between Prince George and the Alberta border.

Sipping a glass of Sandhill, I'm thankful for plate tectonics and the cultivation of the pinot gris grape.

Wednesday 5 October 2011

Sunday 2 October 2011