The concurrent volcanic activities of Mt. Mayon and Mt. Pinatubo in the island of Luzon, Philippines, offer a rare opportunity to compare and contrast the petrology and mantle source signature of the East and West Philippine volcanic arcs. Mt. Mayon belongs to the East Arc wherein volcanism is associated with the subduction underneath Luzon of the Philippine Sea Plate with thin pelagic sediment cover whereas Mt. Pinatubo belongs to the West Arc wherein volcanism is the result of the eastward subduction of the South China Sea Plate with moderate terrigenous sediment cover. We propose a combined field and laboratory investigation of volcanic rocks from Mt. Pinatubo and Mt. Mayon. In the field, we will map and try to collect representative samples from the oldest to the youngest eruptive products of both volcanoes. In the lab, samples collected will be analyzed for their petrography, mineralogy, bulk major and trace element chemistry, and Sr, Nd, and Pb isotopic compositions. The proposed investigation is a collaborative effort among workers from the Scripps Institution of Oceanography, United State Geological Survey and Philippine Institute of Volcanology and Seismology.
