District Manager | Median Annual Salary: $72,402. Salary outlook: Retail district managers at Walgreen Co. can make an average $128K and Sears Holdings Corporation, CVS Caremark Corporation and Family Dollar Stores Inc. are some of the top-paying firms where district managers see a range of $88K to $114K.
Volcanic eruptions are caused when magma from the magma chamber of the Earth rises up the pipe and out of the vent.Magma is continuously supplied from the mantle of the Earth. Shield volcanoes usually have a gentle eruption, as it contains basic lava.nother type of eruption in what is known as a boiler volcano results from water that gets trapped inside porous rock, and is then heated by the mantle, until is turns into steam and the steam pressure causes the volcano to explode. These explosions can be extremely large.
A volcanic eruption is the release of molten rock and volcanic gases through Earth 's crust to the surface. Molten rock within the earth, or magma, is driven to erupt by buoyancy because it is lighter than the surrounding rock. Dissolved gases within the magma are under great pressure and force magma upwards.olcanoes are vents or fissures in Earth 's crust through which lava, gases, and pyroclastic debris are released. More commonly, the term volcano refers to the landform built up from the accumulation of lava and/or pyroclastic debris.