massive volcano eruption indonesia

The fate of northern Krakatoa has been the subject of some dispute among geologists. It was originally proposed that the island had been blown apart by the force of the eruption. However, most of the material deposited by the volcano is clearly magmatic in origin, and the caldera formed by the eruption is not extensively filled with deposits from the 1883 eruption. This indicates that the island subsided into an empty magma chamber at the end of the eruption sequence, rather than having been destroyed during the eruptions. The established hypotheses – based on the findings of contemporary investigators – assume that part of the island subsided before the first explosions on the morning of August 27. This forced the volcano's vents below sea level, causing: massive flooding which created a series of phreatic explosions (interaction of ground water and magma). seawater to cool the magma enough for it to crust over and produce a "pressure cooker" effect that was relieved only when explosive pressures were reached. However, there is geological evidence which does not support the assumption that only subsidence before the explosion was the cause. For instance, the pumice and ignimbrite deposits are not of a kind consistent with a magma-seawater interaction. These findings have led to other hypotheses: a massive underwater land slump or partial subsidence suddenly exposed the highly pressurized magma chamber, opening a pathway for seawater to enter the magma chamber and setting the stage for a magma-seawater interaction. the final explosions may have been caused by magma mixing caused by a sudden infusion of hot basaltic magma into the cooler and lighter magma in the chamber below the volcano. This would have resulted in a rapid and unsustainable increase in pressure, leading to a cataclysmic explosion. Evidence for this theory is the existence of pumice consisting of light and dark material, the dark material being of much hotter origin. However, such material reportedly is less than five per cent of the content of the Krakatoa ignimbrite and some investigators have rejected this as a prime cause of the 27 August explosions. File:KrakatoaHV.webmPlay media Numerical model of hydrovolcanic explosion of Krakatoa and Tsunami generation. A numerical model for a Krakatoa hydrovolcanic explosion and the resulting tsunami was described by (Mader & Gittings, 2006).[21] A high wall of water is formed that is initially higher than 100 meters driven by the shocked water, basalt and air.

HDVideoRidha, Information, Google+, autovehiclex.blogspot, massive volcano eruption indonesia, most active volcano, volcano facts, about volcanoes, Indonesia, watch video volcanoes, lava lake, Volcanic eruption, discover, volcanic landscape, red hot lava, geographic, types of volcano, magma, layers of lava, massive underwater land, mountain,