A River Runs Under It
In the 62-mile-long Monterey Canyon, off the
California coast, fast-moving torrents of water and sediment
sculpt the undersea world, just as rivers and landslides
carve out canyons on dry land.
Courtesy of David Divins, NOAA National Geophysical Data Center
DEPTH
The image on this page comes from the Coastal Relief Model, an ambitious effort by the National Oceanic and Atmospheric Administration to assemble a single continuous map of the entire U.S. coastline’s seafloor. |
1. Swept Away: Each year more than 14,000 cubic feet of offshore sand is swept into the canyon—grist for undersea landslides and turbidity flows.
2. BURIED: In 2001 scientific canyon-monitoring equipment was carried hundreds of yards and buried by tumbling sediment. Small debris flows can build into giant turbidity currents, which travel for hours and for hundreds of miles.
3. SHAKEN, STIRRED: Active fault lines generate periodic earthquakes and landslides; these have carved prominent twists and turns into the canyon over time.
4. FED FROM ABOVE: Organic particles carried from far “upstream” support weird creatures at these depths, such as brittlestars, pom-pom anemones, and sea fans.
5. FOUND: Marine zoologists recently made headlines with the discovery here of the first known bone-eating worms, devouring the skeleton of a sunken whale.
6. CONTAMINATED: Turbidity flows carry nutrients—and toxins. The pesticide DDT, sprayed on California crops until three decades ago, can be found throughout the canyon, even to its very end.
