A Mystery 10 Million Years in the Making
How scientists track down clues to Earth’s history
Geology is a forensic science. It doesn’t easily lend itself to experimentation, leaving geologists with observation as their primary tool of investigation. Yet our planet is notoriously good at covering its own tracks. If a crime was committed a billion years ago, plate tectonics and erosion have likely removed any evidence of it. What remains is often an incomplete picture, a patchwork of clues that could each mean many different things on their own, or nothing at all. It’s up to the scientists to put a complete story together.
Subduction, burying the evidence
Geologists have become very crafty at looking for clues, often arriving at conclusions by way of analogy or searching for evidence of large-scale processes under the lens of a microscope. In Papua New Guinea the history of plate tectonics is hidden in a grain of sand. Professor Suzanne Baldwin and her team at Syracuse University recently published their research on fluid and mineral inclusions discovered inside garnet sands. Garnet beaches are as rare as they are beautiful. The mineral gives a ruddy hue to the country’s coastline while the blue waters of the Pacific Ocean lap at its edge.
