If humans become extinct (or perhaps more accurately, ‘when’ they become extinct) what evidence would be preserved in the Earth’s geologic strata 100 million years in the future? This is the question Jan Zalasiewicz loosely examines in The Earth After Us: What Legacy Will Humans Leave in the Rocks? Although this is a similar premise to Alan Weisman’s book The World Without Us, Zalasiewicz approaches the topic from a geological and paleontological point of view.

While the premise is moderately interesting, the bulk of the book focuses on an explanation of current and past geological events and the processes which lead to fossilization – a subject that is more interesting than the thought experiment in my opinion. Zalasiewicz does quite a good job delving into the sciences of plate tectonics, climate change, fossilization, and paleontology to explain the uniform processes at work which slowly alter the face of the planet. In the final chapters he theorizes the extent to which man-made artifacts and human remains will be preserved. The answer isn’t a big surprise. The extent to which we’re changing the face of the planet today will leave evidence of our presence for some time to come.