What have scientists learned from their studies of microbial activity in steam fumaroles and thermal springs around the volcano?
The 900-foot tall lava dome that formed in the crater between 1980 and 1986 still retains a considerable amount of heat today. Erosion from flooding and seasonal run-off has cut deep gullies in the crater floor. Where the groundwater beneath the dome is exposed hot, mineral rich thermal springs occur. These thermal areas provide a special habitat for bacteria and other microbial life. [Tim Lichen, 1990] The high nutrient, low oxygen conditions that existed at extreme temperatures following the eruption and still persist in steam fumaroles and thermal springs draining the deposits were similar to the conditions that existed during the early stages of the evolution of life on earth. Microbiologists have repeatedly sampled steam fumaroles and thermal springs to study primitive bacteria (Archaebacter spp.) that occur only in volcanic areas and in very high temperature vents deep on the ocean floor. Arrows point to a cross-sectional view of archaebacter as seen through a powerful electron m
