Modern western square dance of "patter calls" and "singing calls", the two types of square dance calls. The logos shown on the right are the international square dance logo and the modern Alliance of Round, Traditional and Square-Dance logo. Modern western square dancing is a non-competitive activity. There are no dance competitions, and apart from fun events, no prizes are ever offered or sought for 'best dancer' or 'best square'. Particularly at the 'challenge' levels there is large degree of personal satisfaction to be gained from the problem solving element of completing a dance. At all levels the main elements are to enjoy the
Types of volcanic eruptions face is strong enough to withstand the explosive force, outright eruptions may not occur, although cracks in the rock will probably develop and weaken it, furthering future eruptions. Often a precursor of future volcanic activity, phreatic eruptions are generally weak, although there have been exceptions. Some phreatic events may be triggered by earthquake activity, another volcanic precursor, and they may also travel along dike lines. Phreatic eruptions form base surges, lahars, avalanches, and volcanic block "rain." They may also release deadly toxic gas able to suffocate anyone in range of the eruption. Volcanoes known to exhibit phreatic activity include: Types