Geological History of Canada: The Last Foot of Rail, the End of the Line
Byron King recounts the biological and Geological History of Canada, refiguring it as a trip along the Halifax-Vancouver railway, and shows how this long, long timeframe was necessary for the creation of oil.
IF YOU WANT to think about geology, Vancouver is as good a place to ponder Earth science as any town in any land. The mountain cores of Vancouver and environs are remarkable products of Mesozoic sediment deposition and Tertiary uplift, a fancy-sounding way of characterizing the past 300 million years or so of Earth’s history.
The geologically slow driving force, over the past many millions of years, has been tectonism and associated plutonism and volcanism.
Tectonism is a term that describes the processes and geophysical forces that move and deform the Earth’s crust on a broad scale. (Think about the term “plate tectonics” and the Earth’s architecture.)
Plutonism is a term that describes the geological activity associated with rocks being formed and altered at depth within the Earth. (Think about the Earth’s hot interior.)
Volcanism is a term used to describe igneous processes that affect the surface of the Earth. (Think about…well, volcanoes.)
For almost 300 million years, a long and complex series of large events, and dynamic processes of immense scale, have created and shaped the western part of North America. For almost all of those 300 million years, the North American plate, the part of the Earth’s crust upon which is located most of Canada, the United States, and much of Mexico, has slowly but inexorably been moving westward.
The western margin of that tectonic plate, now called the Cascadia Subduction Zone, has been altered by the intrusion of molten rock from below and by the associated heating and earth-movement activity. We see this grand scale of planetary geology from the volcanoes of the Pacific Rim “Ring of Fire” to the faulting of the Western regions of North America, to the massive granite bodies that form the cores of entire mountain chains from Alaska to Panama.
On a more localized scale, the regional geology of the Vancouver area is also a product of great events in Earth history, played out over a span of time that challenges human comprehension, if not imagination. The present topography of Vancouver and environs was shaped by relatively recent events, at least in terms of geologic time, applied to those larger events.
The vistas of Vancouver offer visions of steep mountainsides dropping into rich river valleys. The underwater charts show submerged offshore slopes that dive deep beneath the Strait of Juan de Fuca. Most of these features are products of the past 2 million years of Earth dynamics, popularly known as the Ice Age.
Stand anywhere in this cosmopolitan locale and ponder the fact that up until about 10,000 years ago, you would have been at the bottom of a mile of ice.
For 2 million years before, throughout the Pleistocene Epoch, ice came (mostly) and went (on occasion) with the Earth’s climate changes. The glacial ice filled the previously existing river valleys that had been carved by moving water during the Tertiary Period, spanning the past 65 million years or so. Movement of the ice during the past 2 million years literally scraped and gouged out the sides and bottoms of whatever bedrock it touched. Geologically speaking, the Pleistocene ice forced itself into narrow cracks in the earth and made them wide. The ice took openings that were shallow and made them deep. Thus we have the high mountains, steep hillsides and deep valleys of the Vancouver region.
When the great ice sheets finally melted, gravity did what it always does — it pulled the water downhill. When the velocity of the moving water diminished, its power abated, and that same gravity deposited the glacial loads of rock and other earth material. These materials landed on the hard surface of the Earth’s crust. The process left the bedrock geology of Vancouver pretty much as we find it today, with relatively recent glacial sediments and alluvium covering the far older rock formations beneath.
Geological History of Canada: When the Ice Melted
As the Pleistocene ice melted, worldwide sea levels rose in consequence by about 300 feet (about 90 meters), as water formerly locked up in ice flowed downhill and returned to the ocean basins of the world. This rise in worldwide sea levels submerged the lowest of coastlines and river valleys, drowning what had been valleys and ancient shorelines.
This process has given us such large geographic features as the Baltic Sea, the Persian Gulf, Hudson Bay and the geologically recent creation known as the Black Sea, among many Earth features.
And this process of rising sea level also gave us smaller features such as, among many others, North America’s Chesapeake and San Francisco bays, the St. Lawrence and the Hudson river valleys, the island of Manhattan, and Cape Cod. I mention these places not to be exhaustive, but simply to give some perspective to, and comparison with, the drowned river valley where we find today the beautiful city of Vancouver. If you have never been here, it is well worth the trip.
Even a nodding acquaintance with the science of geology will improve one’s perspective on Vancouver. A pleasant drive on Vancouver’s scenic roads, or a brisk stroll or bicycle ride in the forest environment of Stanley Park, adjacent to downtown, gives the visitor an immediate and rock-solid lesson in the past several million years of Earth history. If you know where to look, and if you understand what it is that you see, there is geology aplenty — enough for any curious amateur, let alone the field work for many a Ph.D. thesis.
But aside from its numerous and scenic vistas, Vancouver also provides another place to experience a different perspective on a part of geologic history. That locale is the train station.
At the edge of downtown Vancouver, adjacent to that city’s remarkable Chinatown, stands the Pacific Central railroad station. Built in the early 1900s of gray limestone and granite, several stories high and faced with imposing neoclassical columns, this structure houses the terminus of the rail line that has its start 4,500 miles (7,200 kilometers) to the east in Halifax, Nova Scotia.
Canada’s railroads are laid out more or less east-west, in a fairly straight line across the country. Starting in Halifax, the rail lines run west through the Maritime provinces and Quebec to Montreal. From Montreal, the track of the line follows a roadbed to Ottawa and then Toronto. From the northern edge of Lake Ontario, the railway passes through the rich farmlands of lower Ontario and winds along the north shorelines of the Great Lakes. Then, after skirting Lake Superior, the railroad cuts across the flat prairie through Winnipeg and Saskatoon, and thence to Calgary and Jasper. Finally, the railroad right of way cuts a winding path, following the valleys and punching through the mountains of the mighty Canadian Rockies, to the last stop in Vancouver, near the edge of the Pacific, our planet’s largest ocean basin.
The railway across Canada is a long haul from one end of the country to the other, mile after seemingly endless mile, many days of a locomotive’s hard pull under the best of circumstances. When passengers arrive in Vancouver, they have almost always come from afar. They are typically travel weary and happy to exit the train cars and walk eagerly, if not briskly, down the platform on their way into the station and out to the siren-like charms of one of the world’s great cities.
Along that last promenade in Pacific Central Station, it is understandable that few bother to consider the last stretch of rail that carried them so far. But it is worth it, I believe, to take a moment to think about the continuous ribbon of steel that winds its long way across North America.
Start at this spot, not far from the vast Pacific Ocean, and cast your gaze back up the line. Imagine your way along those shiny steel rails, back across a continent to Halifax Station, which is in sight of the cold Atlantic. And for our purposes, I simply note that before heading off to enjoy the pleasures of Vancouver, you should look carefully at the last foot of rail that is, quite literally, the end of the line.
Consider those 4,500 miles of rail line from Halifax to Vancouver as representing a timeline of geologic history, from the formation of the Earth to the present. Assign a span of, say, 4.5 billion years to the length of the line, or what the astronomers and astrogeologists estimate is the span of time since the Earth’s formation from dust and gases orbiting a proto-sun. Take those 4.5 billion years and divide by 4,500 miles of rail. How convenient is the math, because every mile of track represents about 1 million years of geologic time: one mile to 1 million. Think of it in those terms. If a mile of rail is a million years of time, then long division tells us that every foot of rail represents about 190 years of Earth history.
Geological History of Canada: The Last Foot of Rail
NOW LOOK AGAIN at that last foot of rail, the end of the 4,500-mile-long trail of steel. After crossing a continent, that last foot of rail represents 190 years of history, since about the age of Napoleon or a time since the Industrial Revolution began to take hold throughout the world. Coincidentally, the beginning of that last foot marks the date of the birth of a child in upstate New York by the name of Edwin L. Drake, a man with whom we have become acquainted through other articles in Whiskey & Gunpowder. Hold that thought for a few moments while we ponder all of the rest of Earth history that lies beyond, back up the tracks and through the mountains and across the prairies, all the way to the other end of a great continental landmass.
Look at this timeline along the railroad from the other direction. Halifax, on the east coast of Canada and marking the beginning of the time chart, would represent the oldest geologic time, the formation of the Earth. The next 4,000 miles of rail across Canada to the West, to a point about 30 miles east of Jasper, Alberta, is what the geologists call Precambrian time.
This vast, 4-billion-year stretch of time covers the period from the formation of the Earth as a planet to a time when the Earth began to leave significant evidence in the rock record of what was happening. During this Precambrian time period, the crust of the Earth was altered by bombardment by asteroids and other extraplanetary bodies, as well as by heat flow outward from the planet’s churning interior. The crust cooled and developed into distinctive continental masses and ocean basins, as Earth dynamics followed the laws of thermodynamics and manifested through plate tectonics.
The Earth’s atmosphere and hydrosphere both became defined during the Precambrian, although the chemistry of both was quite different from what we know today. Primitive forms of life appeared, as evidenced today by fossilized mats of what are called stromatolites, created by primitive blue-green algae. The era also left evidence of its astonishing biology via other fascinating fossil beds, such as the Burgess Shale of western Canada.
The evidence is that this type of Precambrian life developed along the basis of photosynthesis, turning carbon dioxide from the primitive atmosphere into free oxygen. Other electrochemical and photochemical processes acted on the free oxygen to create ozone, a critical substance that drifted upward to form a protective layer at the top of the atmosphere and shield the Earth’s surface from bombardment by the deadly cosmic rays of the sun. In short, this Precambrian stretch of years was the time in which the Earth was transformed from a dead planet to a living one, although nothing remotely similar to what we know today.
If a train left Halifax, advancing through time with each mile it moved west across the rails, it would have to travel almost 90% of the way across Canada just to reach Cambrian time. With most of the trip accomplished, this time-traveling train would approach the Canadian Rockies before crossing the point in time, the beginning of the Cambrian period, when the first significant numbers of fossils begin to appear in the geologic record.
On this rail trip through time, the final 500 miles of the Trans-Canada Railway, from Jasper to Vancouver, represent the Paleozoic, Mesozoic and Cenozoic Eras. These periods of geologic time represent a relatively brief period — relative to the age of the Earth, and certainly in the context of the universe — of half a billion years. It is a lot of years in many respects, but in the cosmic scheme of things, it is a blink of an eye.
The past half a billion years is a period of time that is best defined by the presence of living things on Earth that are based on multicellular biology, both plant life and animal life, with sufficient substance to leave fossilized evidence in the sedimentary record. That is, these plant and animal organisms, in their own respective times and manners, built up complex ecosystems. And after their death and burial under subsequent sediment deposition, they have left (in some cases, but by no means all) a detailed fossil record. Life during this time has evolved through almost infinite transformations. Even the vast fossil record that mankind has unearthed to date reveals only a small fraction of the hundreds of millions of species that have come and gone.
What we know from the fossil record is that Paleozoic time brought forth invertebrate animals, which left fossil shells and skeletons on ocean floors to be buried under more sediment. These were followed, over time, by primitive fish. Some of the evolutionary successors to the fish colonized the land with primitive reptiles, in parallel with aquatic plants evolving into terrestrial ferns. The most commonly recognized ancient plants from this time in geologic history are the lepidodendron, which died and were buried, and through complex geologic processes metamorphosed into the Carboniferous coal measures that appear on several continents.
Mesozoic time brought the Earth an explosion of land-dwelling life, most famously illustrated by the so-called “age of dinosaurs,” although any self-respecting paleontologist or paleobotanist will raise a finger to say, “Yes, but…” That’s OK, my friends. We will say it for you. Yes, but…there were many other things occurring during Mesozoic time as well besides those big old dinosaurs. Flowering plants, for example. But for now, however, for this humble article, we must simply note the fact and pass by on our train trip across time.
Cenozoic time, from the end of the Cretaceous Period to the present, brought the Earth its age of mammals. Small creatures that formerly dwelt in the shadows of dinosaurs had their time in Earth history to rise to dominance of the planet’s ecosystems, certainly on land. (And at sea, the rise of mammals brought whales and other sea mammals to the top of the oceanic food chain as well.) As with the Mesozoic, there was much else to characterize the passage of so much time, but at a million years per mile, the train moves rapidly past much that is truly fascinating in its own right.
Geological History of Canada: Things Happening in the Depths of the Earth
Through all of this time, sunlight and the hydrologic cycle gave life to things on Earth. As a famous Book states, “To all things there is a time, and there is a time for all things under the heavens.” Each and every creature had its time, year after year, age after age, era after era. The Earth turned, the sun rose. The Earth turned, the sun set.
Each creature under the heavens had its own moment, literally, in the sun. And then one sunset was its last. What had been alive went its own way into death. “Ashes to ashes, dust to dust” being a phrase with meaning beyond its common use as a graveside blessing. Inexorably, gravity pulled down the last remains, and in some instances, erosion and subsidence buried the residue under additional layers of sediment. Sealed within the depths of the Earth, other things happened involving time and heat and motion. Other very important things.
Throughout all of the time frames only briefly described here, the Earth was dynamic. The sun powered the hydrologic and atmospheric cycles, moving water and air currents across the top of the crust and weathering and eroding the rocks. The Earth’s internal energy, its internally generated heat and resultant “tectonic” energy, caused the uplift of rocks from within the crust, which rocks were then eroded down.
This tectonic activity was manifested in faulting and rifting, by volcanism and earth movement on scales both local and vast. Over lengthy periods of geologic time, continents and ocean basins changed shape and form as the uplift of entire regions led to erosion. Hills and mountains rose and fell. Shorelines moved, and rivers drained upland basins of their sediments. Erosion led to deposition of these sediments downstream or downwind. And deposition of these sediments in offshore basins led to subsidence of the Earth’s crust.
In the period of time since the Cambrian, the past 500 million years or so, and where geological conditions were just right, some traces of this ancient life were preserved in the sediments. These traces were preserved not only as the skeletal fossils, but also as carbon-based organic matter and residue. This organic residue, whatever was left of life long ago, was buried beneath other sediments that followed from above, and it all subsided deeper and deeper into the basins of the crust.
Over periods of time ranging from a few million years to many hundreds of millions of years, this organic matter changed with depth of burial, with pressure and with increasing temperature. In its own way, through the internal refining processes of Earth’s incomparable thermal dynamics, this material metamorphosed into what we know today as fossil fuel — as coal, oil, and natural gas.
Geological History of Canada: Ancient Sunshine
When people say that fossil fuels are “remnants of ancient sunshine,” they are only partly correct. What we see today is ancient organic matter that grew and thrived under the sun of millions of years ago, that had its time under the heavens. But it is also organic matter that has been refined within the Earth. That is, the fossil fuel that mankind digs or pumps out of the depths of the Earth is made of the raw material of ancient organic matter, but raw material now refined to a higher degree of chemical complexity and energy density by the Earth’s tectonic energy. Tectonic energy has altered the original compositions and chemical structures of the organic matter through burial and heat flow.
Tectonic energy is a broad term that includes the Earth’s gravity, which pulled the material to a low spot on the Earth’s surface, pulled other material down on top of it as sediment, and eventually caused the subsidence of a block of sediments into a basin of the Earth’s crust. Tectonic energy also includes the heat energy from radioactive decay of materials within the Earth and the heat flow that penetrates sediments that subside to depth. And tectonic energy includes the energy of the Earth’s interior, which has moved the blocks of sediment, folded them, faulted them, and lifted them up, opposite the pull of the Earth’s gravity. To illustrate, think of the energy that was required to mobilize and lift a block of limestone, deposited beneath a shallow sea, from the interior of the Earth upward to form part of the Himalayan mountain chain. Think of the process that raised from the aqueous depths the limestone that is exposed at the top of Mt. Everest.
As the organic material was altered by tectonic energy, in many places, it became mobilized and migrated to other parts of the geologic column. We see that today in features such as oil- and gas-bearing formations, where these fluids have flowed from oil-forming shales into adjacent sandstones or limestones. And the miracle of nature is that the Earth’s dynamic processes have also moved these fossil fuels — through subsequent tectonic activity and the uplift of portions of the Earth’s crust — to places where they can be accessed by the digger’s pick or the driller’s bit.
Most recently, in the blink of an eye geologically speaking, the era in which we live (some people call it Holocene) saw the rise of mankind. Within a few tens of thousands of years, according to the archaeologists, human beings have proceeded from scratching out a bare existence using stone tools and fire to the modern economic world.
Ours is, in short, a world now powered and lubricated, in no small part, by the fossil fuels that are the legacy of hundreds of millions of years of Earth dynamics.
And here we are today, standing (well…I am standing; you are reading about it…) on the platform of the train station in Vancouver, pondering geologic time while looking at the last foot of a long track.
It all comes back to that last foot of rail, at the end of the line in Vancouver.
The first 4,500 miles of steel rail, minus that last foot, represent the time it took for Earth’s dynamics to create the planet’s geological legacy of sedimentary basins full of fossil fuels. That last foot of rail, representing about 190 years of recent human history, is the time it took for mankind to locate just about all of the sedimentary basins that are there to be found. And that 190 years has been the time it took for mankind to produce not quite one-half of all the liquid petroleum that will ever see the light of day (or see the light again, if you think about it) out of those sedimentary basins. (Well, really, it has mostly been the past 95 or so years, or the last 6 inches of rail, in which half of the easily accessible petroleum has been produced.) As for natural gas and coal, the past 190 years of production and consumption has not yet brought the Earth to the halfway point of its geological legacy, but based on the current trends, we are moving there as well.
Let me perhaps overstate the point. During a span of 190 years, mankind has burned up a geological legacy that took the earth 4.5 billion years to produce. Or maybe it has only been 500 million years, if you want to start the clock at the beginning of Cambrian time. But mankind is burning it up a lot faster than the Earth ever made it.
The world’s fossil fuel economy as we know it — or maybe I should say “knew it” — is not sustainable in any conceivable manner, and you should plan on the fact that just about everything you know is going to change, and change profoundly. One of the things that will change fast is the price of oil in a world economy where global daily production peaks and begins to decline. Other things will change in their own time and way. As the previously cited famous book says, “The wind blows where it will, and you hear its voice, but know not whence it comes and where it goes.”
The world is made up of many different people, no one of whom can accomplish everything. But every person can, and I believe that every person should, ponder the meaning of that last foot of rail at the end of the line. Any person — or any group of people who work together, or any collection of groups that constitute a nation — that is not looking at things in a different way and working to figure out what comes next, or to invent a new future for mankind, will be left in the dustbin of history.
Until another time…
Byron W. King
March 1, 2005