Activity at Manam's two summit craters remained low during July. The summit area remained mostly cloud-covered during the month; however, when the clouds cleared both craters were releasing white vapor at weak-to-moderate rates. No seismic recording was carried out due to shortage of recording paper. There was no night-time glow observed during the month. Remote sensing scientists working with the MODIS Thermal Alert System noted that no new activity was detected by MODVOLC from 1 January 2003 to 31 May 2004.

Geological Summary. The 10-km-wide island of Manam, lying 13 km off the northern coast of mainland Papua New Guinea, is one of the country's most active volcanoes. Four large radial valleys extend from the unvegetated summit of the conical basaltic-andesitic stratovolcano to its lower flanks. These valleys channel lava flows and pyroclastic avalanches that have sometimes reached the coast. Five small satellitic centers are located near the island's shoreline on the northern, southern, and western sides. Two summit craters are present; both are active, although most observed eruptions have originated from the southern crater, concentrating eruptive products during much of the past century into the SE valley. Frequent eruptions, typically of mild-to-moderate scale, have been recorded since 1616. Occasional larger eruptions have produced pyroclastic flows and lava flows that reached flat-lying coastal areas and entered the sea, sometimes impacting populated areas.

Information Contacts: Ima Itikarai and Herman Patia, Rabaul Volcano Observatory (RVO), P. O. Box 386, Rabaul, Papua New Guinea; Rob Wright, Luke Flynn, and Eric Pilger, MODIS Thermal Alert System, Hawaii Institute of Geophysics and Planetology (HIGP), School of Ocean and Earth Science and Technology, University of Hawaii at Manoa (URL: http://modis.hgip.hawaii.edu/); David A. Rothery and Charlotte Saunders, Department of Earth Sciences, The Open University, Milton Keynes, MK7 6AA, United Kingdom.