Are there any modern examples of rapid sedimentation?
The 1980 eruption of Mount St. Helen’s caused 90 mph mud flows of melting snow and volcanic debris. These mud flows caused tremendous sedimentation. A subsequent eruption created additional mud flows that eroded large canyons. One of these canyons has even been named “Little Grand Canyon”, as it is only 1/40th the size of the real one. All this sedimentation has since formed into rock. So sedimentary rock can form rapidly under the right conditions. The thousands of fossils in the Grand Canyon were (apparently) mauled and violently churned about by some huge force. One fish was buried so fast that it is frozen into the rock wall giving birth! Most Creationists argue that these fossils are the work of the great flood. What else could have caused such mass destruction? A tidal wave is thus far the only rational way to explain it.
