The extremely diverse foraminiferal fauna of the Timor Sea off northwest Australia will be studied. Numerous traverses were made across the Sahul Shelf, a broad stable continental platform bordering the low-lying deeply weathered Australian continent, across the adjacent tectonically unstable geosynclinal Timor Trough. Sample sites range from 20 m to nearly 3500 m in water depth. Published lithologic studies of the same cores include data concerning water depth, bottom relief, and detailed character of the bottom sediments, including percent CaCO3 and percent organic carbon. Most previous detailed distributional studies of foraminifera have been made in clastic depositional environments, as on the eastern and western coasts of North America, or in the Gulf of Mexico. Previous published studies of carbonate shelves have had a limited number and depth distribution of samples, hence less diverse foraminiferal faunas. In contrast, the sedimentological, structural, and climatic setting of the Timor Sea strongly resembles that of biotically diverse Paleozoic and Mesozoic epicontinental seas. Over 1000 species comprise its extremely diverse fauna. Assemblages will be determined by factor analysis of counts of the living fraction. The faunas will be compared with the known sedimentological and other characteristics to provide a basis for interpretation of similar calcareous deposits of the geologic past.