Sunday, 30 April 2017

THE BIRTHPLACE OF LIFE

For millennia, we've sat at the edge of the world, taking in the impossible magnitude of the ocean.

Her beauty, her storms, such abundance and diversity of life amidst both the tranquility and unforgiving power that this immensely deep and mostly unexplored frontier hold for us.

Our distant relatives and even those who meditate on these vast pools of blue and green today see the ocean as the birthplace of life. It's the story we tell our children, and they, in turn, tell their children's children.

It's a reasonable conclusion. Upwelling currents bring cold, nutrient-rich water from the bottom to the surface. In this primordial soup, vitally important organic and inorganic compounds mix ceaselessly and give us the perfect conditions for photosynthesis, and by all accounts, the basic building blocks of life.

But, rather than the birthplace, I postulate that the ocean is simply the mixing ground for the expansion of life that began elsewhere. It is also possible, as yet we do not know, that these two streams ran in tandem. The delight of science is that we may one day know for sure.

From the oceans, it's just a slow crawl, evolutionarily speaking, from the sea to the terrestrial life we see today.

So where to look for the beginnings. That story is a much harsher one. We find microbes of the Domain Archaea, prokaryotic single-celled microorganisms, distinct from bacteria and eukaryotes, living in some of the world's most unlikely and inhospitable places.

Extremely adaptable, Archaea not only survive but thrive in harsh environments, hot, cold, brutally acidic, you name it. But beyond the hot pools and salt lakes, they have also been found in rather pedestrian habitats, in soils, marshlands, and our oceans.

You may be surprised to learn that in this very moment, they are living in your colon, oral cavity, and skin. The methanogens that inhabit our guts have a symbiotic role, helping us with digestion.

Archaea possess genes and several metabolic pathways that allow for transcription and translation. They are able to access more energy sources than their wee microorganism peers, making use of sugars, ammonia, metal ions and hydrogen gas.

The salt-tolerant, Haloarchaea, use sunlight as an energy source. All reproduce asexually by binary fission, fragmentation or budding and have been doing so for a very long time.

Much to our surprise, Archaea have been found making their home in granite more than 3 kilometers beneath the Earth's surface.

Well-preserved Archaea microfossils can be found between the quartz sand grains of the oldest known beach on Earth at Strelley Pool, about 1,500 km north of Perth, Australia. They were thriving here over 3.4 billion years ago in an oxygen-free world, metabolizing sulphur-based compounds and giving rise to the life we see today.

But there are also tubelike fossils, stromatolites, possible ancient microbial mats found in 3.77 billion-year-old rocks. Are these the birth of life? The court's still out. Plate tectonics is the Earth's greatest recycling program with only a handful of outcrops older than 3 billion years. Combine that with baking, cooling, subduction and pressure and it makes solving this ancient mystery even more challenging.

So, the birthplace of life? So far, the best contender are the wee beasties from the planet's oldest beach.



Saturday, 29 April 2017

Friday, 28 April 2017

Sunday, 23 April 2017

EOCENE PLANT & MAMMAL SITE

Reinforcing the block to safely transport the fossil trackway

Saturday, 22 April 2017

GLACIAL FJORD: SEA TO SKY















A short 90-minute drive north of the city of Vancouver, the nation's gateway to the Pacific, is a recreational Shangri-La that attracts four season adventurers from around the globe to ski, board, hike, mountain bike, kayak and climb the local peaks.

It also attracts professional photographers, and weekend warriors, eager to capture the lively footprint of the village or the perfect stillness in nature. This Saturday, it was the destination of one of my new colleagues, Richard, armed with a camera in his pocket to shoot the scenes that took his fancy. A keen thesis editor and some unpredictable rain dampened those plans.

The North Shore mountains, Grouse, Cypress and Seymour, provide easy access for the happy winter adventurer and a beautiful backdrop to the young city of Vancouver -- Canada's third-largest metropolis, year-round.

They also bring us some of the rainiest, snowiest, coldest and windiest climates in Canada. Combined with the westerly winds off of the Pacific, those lovely peaks make for a panoply of weather extremes on any given day.

Certainly, not as cold as in recent past. And not as warm as millions of years ago. Ice cores tell tales of the ebb and flow of temperatures in this part of the world. Rock cores and sedimentary deposits tell other tales.

While the city sits on relatively young sandstone and mudstone, the North Shore Mountains are made of granite that formed deep within the Earth more than 100 million years ago. There are Cretaceous outcrops of sedimentary rock just off Taylor Way at Brother's Creek that reveals familiar fossilized plant material. Species common in the Cretaceous and still extant today.

This treasure trove wilderness playground stretches along the breathtaking Sea-to-Sky Highway affording breathtaking views of the Pacific as it follows the coastline of Howe Sound, a glacially carved fiord which extends from Horseshoe Bay (20 km northwest of Vancouver), past Lions Bay to the hamlet of Squamish.

It is a short jaunt further north that takes you into picturesque Whistler Valley.

Carved from the granitic mountainside high above Howe Sound, this scenic pathway, blasted into the rock of the steep glacial-valley slope, has been a rich recreation corridor and traditional First Nation hunting ground.

The ground you move over has seen oceans rise and fall, glaciers advance and retreat, the arrival of early explorers, the miners of the Gold Rush and now the rush of tourism.



Friday, 21 April 2017

CaCO3 + CO2 + H2O → Ca (HCO3)2

Those of you who live near the sea understand the compulsion to collect shells. They add a little something to our homes and gardens.

With a strong love of natural objects, my own home boasts several stunning abalone shells conscripted into service as both spice dish and soap dish.

As well as beautiful debris, shells also played an embalming role as they collect in shell middens from coastal communities. Having food “packaging” accumulate in vast heaps around towns and villages is hardly a modern phenomenon.

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 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. Useful this, as antler makes for a fine sewing tool when worked into a needle. Much of what we know around the modification of natural objects into tools comes from this preservation.

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 makes the bone harder and 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.

Wednesday, 19 April 2017

Monday, 10 April 2017

TECTONIC SHIFTING: BAJA BC

Some 270 million plus years ago, had one wanted to buy waterfront property in what is now British Columbia, you’d be looking somewhere near Kakwa Provincial Park between Prince George and the Alberta border. 

The rest of the province had yet to arrive but would be made up of over twenty major terranes from around the Pacific. 

The rocks that would eventually become the Cariboo Mountains were far out in the Pacific Ocean, down near the equator.

With tectonic shifting, these rocks drifted north-eastward, riding their continental plate, until they collided with and joined the Cordillera in what is now British Columbia. Continued pressure and volcanic activity helped create the tremendous slopes of the Cariboo Range we see today with repeated bouts of glaciation during the Pleistocene carving their final shape.

Friday, 7 April 2017

FARALLON PLATE

The Farallon Plate took a turn north some 57 million years ago, sweeping much of western coastal Oregon along with it. 

By the middle Oligocene, the Cascadia Subduction Zone was in full force with growing pressure erupting volcanoes along the Western Cascades, a pattern that was to continue well into the Miocene. 

The soft ocean sediments of Oregon contain beautifully preserved gastropods, bivalves and cephalopods.