Just for example, around 2 billion years ago, igneous and metamorphic rocks formed a gorge, and then around 70 to 30 million years ago, through the action of plate tectonics, the whole region was uplifted, resulting in a high and relatively flat plateau. Five or six million years ago, a river began to carve its way downward (during heavy flooding, the water takes boulders along with it, which act as chisels along the bottom). Further erosion by tributary streams led to the canyon’s widening. In another couple million years, it might be a little deeper still, but mostly it will have continued to widen. That’s how the Earth naturally made a very big hole in the ground, 446 km long, up to 29 km wide and more than 1,800 meters deep. We call it the Grand Canyon. Earth is a fine architect given millions of years, but we humans are moving 156 million tonnes of rock and soil per day. People are moving mountains. They’re changing the shape of the Earth.
This documentary takes a look at the people doing it. Labourers who tunnel through the Earth from above and below provide some interesting insights from a personal perspective – “If all else fails, there’s always dynamite. We always win.” And though many profess to “feeling bad” about obliterating landscapes, it is short-term profit who is driving all that brutal machinery, not long-term critical thinking or morality or common sense.
Earth is an interesting movie with an uninspired title. It would benefit from better editing, both in terms of smooth transitions and tightening up some scenes that are unnecessarily long. I know some 5 year olds who are insatiable when it come to trucks and diggers, and every time I pass a construction site I see a number old old men watching the machinery do its work, but for me this movie ran overlong. Still, it’s a neat little package of stuff we don’t see nearly enough, certainly not all collected together. It makes for thoughtful viewing.