Seismic array classified until the 1990s. Today they become part of the IMS as primary or auxiliary stations. Seismic arrays are not only used to monitor earthquakes and nuclear tests, but also used as a tool for investigating nature and source regions of microseisms as well as locating and tracking volcanic tremor and analyzing complex seismic wave-field properties in volcanic areas. Seismic arrays can be classified by size, which is defined by the array's aperture given by the largest distance between the single seismometers. The sensors in a seismic array are arranged in different geometry patterns horizontally. The arrays built in the
Natural beech wood global climate changes can also have a profound effect on what kind of natural woodland can grow and survive in a specific area. European beech is usually more susceptible to climatic changes than soil-composition and the current global climate change are found to affect the geographical distribution of natural beech wood habitats. The term "Natural" is often confusingly used as a synonym for "Primeval". While primeval woodlands that still exists, are indeed natural, natural woodlands does not have to be primeval per se. Secondary or re-established woodlands can also be natural; it is just a matter of whether a given