Erosion Around a Dud Artillery Shell

May 24, 2011

Photographer: Bill Burton
Summary Author: Bill Burton; Jim Foster

The photo above shows a dud artillery shell that has been on a weathered hillside in Saipan for at least 63 years. It was fired from a battleship during the Battle of Saipan in June of 1944 when it skidded to a stop and failed to detonate. The 16-in (41 cm) shell has experienced a lot of tropical weather over the years, including the occasional typhoon, and serves as a marker for just how much erosion has occurred here since the battle -- about 1.5 mm/year. Like a caprock on a butte, the hard casing of the shell has protected the less resistant soil from eroding away. Photo taken on May 15, 2007.

Photo details: Camera Maker: Canon; Camera Model: Canon PowerShot G6; Focal Length: 12.7mm; Aperture: f/3.2; Exposure Time: 0.010 s (1/100); ISO equiv: 51; Exposure Bias: none; Metering Mode: Matrix White Balance: Auto; Flash Fired: No (enforced); Orientation: Normal; Color Space: sRGB.