Walter Alvarez Walter Alvarez 1940-Present 1940-Present Walter Alvarez and his father (Luis Alvarez) discovered a special layer of rock in many places on Earth. The rock contains iridium. Iridium is rare on Earth but is common in space objects. Walter Alvarez worked in Earth Science as a Geologist. Walter Alvarez and his father (Luis Alvarez) discovered a special layer of rock in many places on Earth. The rock contains iridium. Iridium is rare on Earth but is common in space objects. Walter Alvarez worked in Earth Science as a Geologist. Dr. Alvarez works as a professor at the University of California at Berkeley. He continues to study the tectonic regions of the Mediterranean, as well as geology involving volcanoes and glaciers. Dr. Alvarez works as a professor at the University of California at Berkeley. He continues to study the tectonic regions of the Mediterranean, as well as geology involving volcanoes and glaciers. Due to his rock discoveries, Alvarez created a theory that dinosaurs were extinct due to a giant asteroid that hit the Earth. Most scientists today think that this theory is the most likely explanation for the dinosaur extinction. Due to his rock discoveries, Alvarez created a theory that dinosaurs were extinct due to a giant asteroid that hit the Earth. Most scientists today think that this theory is the most likely explanation for the dinosaur extinction.