This is a really gorgeous article, and I recommend it. Makes me think that the end of our world will come much, much sooner than our sun exploding.
«you would never know this near-endless age was so thoroughly dominated by the terrible reptiles by looking to the rock record of the entire eastern half of North America. Here, dinosaurs scarcely left behind a record at all.
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If, in the final 7,000 years of their reign, dinosaurs became hyperintelligent, built a civilization, started asteroid mining, and did so for centuries before forgetting to carry the one on an orbital calculation, thereby sending that famous valedictory six-mile space rock hurtling senselessly toward the Earth themselves—it would be virtually impossible to tell. All we do know is that an asteroid did hit, and that the fossils in the millions of years afterward look very different than in the millions of years prior.
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the longest-lived radioisotope from radioactive fallout, iodine-129, has a half-life of less than 16 million years. If there were a nuclear holocaust in the Triassic, among warring prosauropods, we wouldn’t know about it.
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You would see our lightning-fast injection of hundreds of gigatons of light carbon into the atmosphere written in the strange skew of carbon isotopes in this rock—as you do in rocks from the many previous carbon-cycle disasters of Earth history. The massive global-warming pulse created by this carbon disaster would be written in oxygen isotopes. The sulfur, nitrogen, thallium, and uranium isotopes in these rocks (to mention just a few) would whisper to you—again, in squiggles on a graph—that the global ocean lost much of its oxygen during this brief but enigmatic interval. Strontium isotopes would tell you that rock weathering dramatically accelerated worldwide for a few tens of thousands of years as sweltering, violent storms attacked the rocks and wore down the continents during a brief, CO2-driven fever.
These trace isotopes may be the most enduring signals of humanity, together telling much of the story of our strange centuries, in only a few centimeters of ocean rock. They will speak, to those who know how to listen, of life-supporting geochemical cycles going haywire in an eyeblink of geological time, hinted at in small samples from our seam of strange strata that interrupts mile-thick formations of otherwise normal rock. Plastic, that ubiquitous pollutant of the oceans, might be detectable by analyzing small samples of this sediment—appearing, like many organic biomarkers in the fossil record, as a rumor of strangely heavy hydrocarbons. Unassuming peaks on a chromatograph would stand in for all of modernity. Perhaps, perhaps, if one was extremely lucky in surveying this strange layer, across miles of desert-canyon walls, a lone, carbonized, and unrecognizable piece of fishing equipment may sit perplexingly embedded in this dark line in the cliffs. Some “epoch” this.
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The clear-cutting of the rain forest to build roads and palm-oil plantations, the plowing of the seabed on a continental scale, the rapid changes to the ocean and atmosphere’s chemistry, and all the rest would appear simultaneous with the extinction of the woolly mammoth.
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In fact, there exists a better word in geology than epoch to describe our moment in the sun thus far: event. Indeed, there have been many similarly disruptive, rapid, and unusual episodes scattered throughout Earth history—wild climate fluctuations, dramatic sea-level rises and falls, global ocean-chemistry disasters, and biodiversity catastrophes. They appear as strange lines in the rock, but no one calls them epochs. Some reach the arbitrary threshold of “mass extinction,” but many have no name. Moreover, lasting only a few tens of thousands to hundreds of thousands of years in duration, they’re all considered events.»
Here, Read This 