Volcano an extinct volcano from a dormant (inactive) one. Dormant volcanoes are those that have not erupted for thousands of years, but are likely to erupt again in the future. Volcanoes are often considered to be extinct if there are no written records of its activity. Nevertheless, volcanoes may remain dormant for a long period of time. For example, Yellowstone has a repose/recharge period of around 700,000 years, and Toba of around 380,000 years. Vesuvius was described by Roman writers as having been covered with gardens and vineyards before its eruption of 79 CE, which destroyed the towns of Herculaneum and
Mold control and prevention in libraries Mold control and prevention in libraries Mold prevention is a conservation activity that is performed in libraries to protects books and other materials from deterioration caused by mold growth. Mold prevention consists of different methods, such as chemical treatments, careful environmental control, and manual cleaning. Preservationists use one or a combination of these methods to combat mold spores in library collections. Due to its resilient nature, mold prevention has become an important activity among preservation librarians. Mold reproduces by releasing spores into the air. It becomes active after being in a dormant state and responds to fluctuating temperature, air flow,