This study will measure surface uplift rates of the Finisterre Mountains of northern Papua New Guinea, one of the fastest uplifting areas in the world. No other study to date has succeeded in measuring uplift rates because the young sedimentary rocks that retain the record are usually rapidly eroded away. The Finisterre Mountains may be unique in preserving a very young (Miocene through Pleistocene) limestone cap. The uplift rate is a crucial quantity to measure in order to separate uplift versus erosion effects on mountain topography, which in turn will clarify the processes of lithospheric dynamics and mountain building. The results will have implications for a wide variety of tectonic problems in mountain belts.