Polka-mazurka Polka-mazurka The polka-mazurka is a dance, musically similar to the mazurka, but danced much like the polka. Many polka-mazurkas were composed by Johann Strauss II and his family. Johann Strauss I did not compose any of this type of music; the first polka-mazurka example written by the Strauss family was in the year 1854 by Johann Strauss II, entitled La Viennoise op. 144.The polka-mazurka was not credited to the Strauss family alone, as many Viennese composers in the 1850s era also wrote many examples. This variant of the polka was seen as cross-cultural, as many of its influences can be
Types of volcanic eruptions Types of volcanic eruptions Several types of volcanic eruptions—during which lava, tephra (ash, lapilli, volcanic bombs and volcanic blocks), and assorted gases are expelled from a volcanic vent or fissure—have been distinguished by volcanologists. These are often named after famous volcanoes where that type of behavior has been observed. Some volcanoes may exhibit only one characteristic type of eruption during a period of activity, while others may display an entire sequence of types all in one eruptive series. There are three different types of eruptions. The most well-observed are magmatic eruptions, which involve the decompression of gas within magma that