Iguassu Waterfalls

September 21, 2010

Iguassu falls
 
PhotographerMike Passow; Mike's Website
Summary Author: Mike Passow; Jim Foster

September 2010 Earth Science Picture of the Day Viewer's Choice

The photo above shows a close up view of the impressive Iguassu Falls on the border of Brazil and Argentina. These amazing falls occur where the Iguassu River, approximately two miles (3 km) wide at the point of the falls, plunge over basalt cliffs, some of which are 260 feet (80 m) high. The basalt cap rocks formed over 100 million years ago. Iguassu Falls is the thought to be one of the widest falls in the world. Actually, hundreds of separate cataracts spread across the Iguassu River. Spotting a rainbow in the vicinity of a waterfall is easy work when the weather is sunny -- just make sure your back is to the Sun. Note also the faint secondary bow. Photo taken on August 11, 2010.

Photo details: Camera Maker: OLYMPUS IMAGING CORP; Camera Model: uT6000,ST6000; Focal Length: 5.0mm (35mm equivalent: 28mm); Aperture: f/5.0; Exposure Time: 0.0063 s (1/160); ISO equiv: 50; Exposure Bias: none; Metering Mode: Matrix; Exposure: Creative Program (based towards depth of field); White Balance: Auto; Flash Fired: No; Color Space: sRGB.