plate interface, with the result being an earthquake signature that had abundant long period seismic signals, which could be an important factor in the tsunami-generation process. Warning A tsunami warning system was not in operation at the time of the shock, but the Pacific Tsunami Warning Center (operated by the National Oceanic and Atmospheric Administration in Hawaii) and the Japan Meteorological Agency posted a tsunami watch, based on the occurrence of a M7.2 earthquake. The bulletin came within 30 minutes of the shock, but there was no means to transmit the warning to the people on the coast that needed to know. Many of those who felt the earthquake responded by moving away from the shore, but not with any urgency. The withdrawal of the sea that exposed an additional of beach created an even more significant warning sign, but in some locations wind waves on the sea effectively concealed the withdrawal that signalled the approach of the tsunami. Tsunami The earthquake and tsunami came on a Monday afternoon, a day after many more people were present on the beach, due to a major national holiday. The waves came a few tens of minutes after the shock (and were a surprise, even to lifeguards) and occurred when the sea level was approaching low tide which, along with the wind waves, masked the initial withdrawal of the sea as the tsunami drew near. Most portions of the south Java coast saw runup heights of , but evidence on the island of Nusa Kambangan indicated that a peak surge measuring had occurred there, suggesting to researchers that the possibility of a submarine landslide had contributed to the magnitude of the tsunami in that area. Runup A portion of the southwest and south-central Java coast was affected by the tsunami, and resulted in around 600 fatalities, with a high concentration in Pangandaran. Two thousand kilometers (1,200 mi) to the southeast at the Steep Point area of western Australia, a runup of was measured, which was comparable to a similar runup in northern Oman from the 2004 Indian Ocean earthquake and tsunami, though in that case it was at a much greater distance of . Within three weeks of the event, scientists from five different countries were on the ground in Java performing a survey of the affected areas, including gathering runup (height above normal sea level) and inundation (distance the surge moved inland