xShadow zone : The shadow zone is the area of the earth from angular distances of 104 to 140 degrees from a given earthquake that does not receive any direct P waves. The shadow zone results from S waves being stopped entirely by the liquid core and P waves being b
Marine scientists long believed that a microbe called Trichodesmium, a member of a group called the cyanobacteria, reigned over the ocean's nitrogen budget. New research results reported on-line today...Read more