1 Billion Years of Tectonic Plate Movement in 40 Seconds
According to plate tectonic theory, the Earth’s surface is made up of slabs of rock that are slowly shifting right under our feet.
Because of this constant movement, today’s Earth looks a lot different from what it did millions of years ago. Today’s animation looks at the Earth’s tectonic plate movement from 1 ga (geological time for 1 billion years ago) to the present-day, via EarthByte on YouTube.
Editor’s note: The video starts at time 1,000 ma (1,000 million years ago), and ticks down at the rate of about 25 million years every second.
The Emergence of Plate Tectonic Theory
Plate tectonics is a relatively new theory—in fact, according to National Geographic, it hadn’t become popular until the 1960s. However, the concept of continental movement was brewing long before it became widely accepted.
In 1912, German scientist Alfred Wegener proposed a theory he called continental drift. According to Wegener’s theory, Earth’s continents once formed a single, giant landmass, which he called Pangaea.
Over millions of years, Pangaea slowly broke apart, eventually forming the continents as they are today. Wegener believed this continental drift explained why the borders of South America and Africa looked like matching puzzle pieces. He also pointed to similar rock formations and fossils on these two continents as proof to back his theory.
Initially, the scientific community wasn’t on board with the theory of continental drift. But as more data emerged over the years, including research on seafloor spreading, the theory started to gain traction.
The Supercontinent Cycle
Nowadays, it’s believed that Pangea was just one of several supercontinents to mass together (and break apart) over the course of geological history.
The exact number of supercontinents is largely debated, but according to the Encylopedia of Geology, here are five (including Pangea) that are widely recognized:
- Kenorland: 2.7-2.5 billion years ago
- Nuna/Columbia: 1.6-1.4 billion years ago
- Rodinia: 950–800 million years ago
- Pannotia: 620-580 million years ago
- Pangea: 325-175 million years ago
According to the theory, this cycle of breaking apart and coming together happens because of subduction, which occurs when tectonic plates converge with one another.
The supercontinent cycle also ties into ocean formation. The below example of the Wilson Cycle specifically keys in on how the Atlantic Ocean, and its predecessor, the Iapetus Ocean, were formed as supercontinents drifted apart:
Source: Hannes Grobe
The Importance of Plate Tectonics
Plate tectonics has been a game-changer for geologists. The theory has helped to explain tons of unanswered geological questions, assisting scientists in understanding how volcanoes, mountains, and ocean ridges are formed.
It’s also valuable for the oil and gas industry since it explains how sedimentary basins were created, allowing geologists and engineers to target and locate vast oil reserves.
Since the theory of plate tectonics is relatively new, there’s still a lot to be discovered in this field of research. However, in March 2021, a report was published in Earth-Science Reviews that, for the first time, visualized a continuous plate model that shows how Earth’s plates have shifted over the last billion years.
The video above visualizes this particular report and accurately depicts the Earth’s tectonic plates’ movement or the observed shift in Earth’s tectonic plates over the years.
This Clever Map is a Window into 19th Century New York City
The early 1800s were a time of rapid change in New York City. This map shows the city in 1836, alongside the modern day metropolis.
The early 19th century was a time of great change for New York, which had already cemented its status as America’s largest city.
The opening of the Erie Canal helped turn the city into a shipping powerhouse, and there was a building boom on the horizon. Cholera epidemics, fires, and riots swept through the city at various points.
This fascinating interactive map, from Esri, is a snapshot of New York City during the tumultuous time (1836 to be exact), overlaid on the modern-day satellite map.
Getting the Lay of the Land
The base map used above is the stunning “Topographical Map Of The City and County Of New–York, and the adjacent Country”, published by the prodigious mapmaker, Joseph Colton.
For easy viewing, the map’s legend is below:
This map includes all the usual features, such as roads and prominent buildings, but it also has some clever secondary information built in as well. For one, shading indicates ares that were more built-up at the time. There are also a number of visual techniques to indicate topographical features as well. After all, NYC wasn’t as extensive as it is today, and much of the land depicted in the map is still undeveloped.
The full map is well worth exploring as well, as there are a number of beautiful illustrations throughout.
Tool tip: Click the X on the info bar to hide it. (Mobile: Click the map, then the magnifying glass.)
The Big Picture: New York City in 1836
At this point in time, development in Lower Manhattan extended until about 14th Street, where buildings began to give way to open spaces. The city’s grid pattern was beginning to take shape, following the Commissioners’ Plan laid out in 1811. At the time, New York was anticipating massive growth, and the straightforward grid pattern was an efficient way to prepare the city for rapid expansion.
In the 1800s, fire was an ever-present danger for city dwellers. In fact, a major fire tore through Lower Manhattan a year prior to when this map was published.
Points of Interest
There are a number of points worth visiting on this map.
Transit Begins to Take Shape
In the 1830s, New York City’s first railroad line—horse powered for its first few years—connected Prince Street to the Harlem River, accelerating the city’s expansion northward from Lower Manhattan. This route is still recognizable today as the Harlem Line.
One very obvious difference between the two maps is how much land has been reclaimed along shorelines in the area. Battery Park City, on the west side of downtown, and the Brooklyn Navy Yard are two prominent examples of infill. Randall’s Island, located near the top of Manhattan, is also an interesting place to observe changes in topography. Randall’s Island is actually made up of three islands that were eventually conjoined in the 1960s.
This interactive map is a great place to explore changes to NYC’s shoreline over time.
Taming the Landscape
Midtown Manhattan is worth zooming into for a couple of reasons. First, the outline of Central Park is visible, although the park would officially be approved until almost 20 years later.
As well, this topographical map clearly shows the numerous outcroppings spread across the island. Manhattan was far from flat in the 1800s, and it took a tremendous amount of effort—starting with gunpowder, pickaxes, and horse-drawn carts—to level the land.
Looking at these historical maps is a reminder that the New York City we know today is the product of hundreds of years of human effort, and that cities continue to evolve over time.
The Problem With Our Maps
Conventional cartographic techniques have caused many to have a skewed perception of the true size of countries. Can an equal-area map provide clarity?
Maps shape our understanding of the world—and in an increasingly interconnected and global economy, this geographic knowledge is more important than ever.
Unfortunately, billions of people around the world have a skewed perception of the true size of countries thanks to a cartographic technique called the Mercator projection. Used just about everywhere, from classroom wall maps to navigation apps, the Mercator projection is the way most of humanity recognizes the position and size of Earth’s continents.
The Mercator Projection
In 1569, the great cartographer, Gerardus Mercator, created a revolutionary new map based on a cylindrical projection. The new map was well-suited to nautical navigation since every line on the sphere is a constant course, or loxodrome. In modern times, this is particularly useful since the Earth can be depicted in a seamless way in online mapping applications.
That said, in this projection style, the sizes of landmasses become increasingly distorted the further away from the equator they get. One trade-off for the utility of Mercator’s map is that it pumps up the sizes of Europe and North America. Visually speaking, Canada and Russia appear to take up approximately 25% of the Earth’s landmass, when in reality they occupy a mere 5%. When Antarctica is excluded (as it often is), Canada and Russia’s visual share of landmass jumps to about 40%.
Canada is the second largest country in the world, but not by much. Here is an “at scale” look at Canada, the United States, and Mexico.
Africa, South Asia, and South America all appear much smaller in relation to countries further from the equator.
And from a North American perspective, countries such as Australia and Indonesia appear much smaller than they actually are. Comparing the landmasses on the same latitude as Canada helps put sizes into perspective.
Greenland is the world’s largest island, but looking at its hyper-exaggerated depiction in the map below, you’d be forgiven for wondering why it isn’t a stand-alone continent. In reality, Greenland is about fourteen times smaller than Africa.
Is Bigger Better?
Though Mercator’s map was never intended for use as the default wall map in schools around the world, it has shaped the worldviews of billions of people. Critics of the map—and similar projections—suggest that distortion reinforces a sense of colonialist superiority. As well, the amount of territory a country occupies is often correlated with power and access to natural resources, and map distortions can have the effect of inadvertently diminishing nations closer to the equator.
In our society we unconsciously equate size with importance and even power. – Salvatore Natoli, Educational Affairs Director, AAG
A prime example of this argument is the “True Size of Africa” graphic, which demonstrated to millions of people just how big the continent is.
Growing awareness of map distortion is translating into concrete change. Boston public schools, for example, recently switched to the Gall-Peters projection, which more accurately depicts the true size of landmasses.
As well, Google, whose map app is used by approximately one billion people per month, took the bold step of using different projections for different purposes in 2018. The Earth is depicted as a globe at further zoom levels, sidestepping map projection issues completely and displaying the world as it actually is: round.
The Road to Equal-Area Mapping
In 1805, mathematician and astronomer, Karl Mollweide, created a namesake projection that trades accuracy of angles and shape for accuracy of proportion. The Mollweide projection has inspired many other attempts at a user-friendly equal area map.
John Paul Goode’s attempt, known as the Goode Homolosine Projection, took this concept a step further by adding interruptions at strategic locations to help reduce the distortion of continents. The resulting shape is sometimes referred to as an “orange peel map”.
Another evolution in cartography was the Dymaxion map, invented by Buckminster Fuller and patented in 1946. In this version, the continents are no longer in their familiar positions—however, there is more spacial fidelity than in previous projection methods. We’re able to see the true proportions of Africa, Northern Canada, Antarctica, and other distortion hot spots.
The Dymaxion map wasn’t created for purely practical purposes. Fuller believed that humans would be better equipped to address global challenges if they were given a way to visualize the Earth’s continents in a contiguous manner.
The AuthaGraph Map
Using a new map-making method called AuthaGraph, Japanese architect, Hajime Narukawa, may have created the most accurate map of the world yet. AuthaGraph divides the globe into 96 triangles, transfers them to a tetrahedron and unfolds into a rectangle.
The end result? Landmasses and seas are more accurately proportioned than in traditional projections.
The biggest downfall of the AuthaGraph map is that longitude and latitude lines are no longer a tidy grid. As well, continents on the map are repositioned in a way that will be unfamiliar to a population that is already geographically challenged.
That said, depicting our round world on a flat surface will always come with some trade-offs. As demand grows for a true equal-area map, it will be exciting to see what the next generation of map projections have to offer.
Map It Yourself
Looking to learn more about maps and map projections? This fantastic tool, created by Florian Ledermann, allows users to take a vast selection of projection styles, and modify them in different ways. This hands-on approach is a fun way to learn how the shape of landmasses shift as the projection changes.
Misc3 weeks ago
Mapped: Countries by Alcohol Consumption Per Capita
Misc3 weeks ago
Here are 15 Common Data Fallacies to Avoid
Misc1 week ago
A Deep Dive Into the World’s Oceans, Lakes, and Drill Holes
Misc2 weeks ago
Visualizing The Most Widespread Blood Types in Every Country
Misc2 weeks ago
The Problem With Our Maps
Misc2 days ago
24 Cognitive Biases That Are Warping Your Perception of Reality
Technology3 weeks ago
From Amazon to Zoom: What Happens in an Internet Minute In 2021?
Misc1 week ago
Ranked: The 35 Vehicles With the Longest Production Runs