How do you do this problem ? 10 points for who ever is first .?

Question

Compare cinder cone volcanoes and shield volcanoes. Explain where each is likely to form, and give reasons for the differences in shape and size.

Answer 1

A) A shield volcano is a large volcano with shallowly-sloping sides. The name derives from a translation of "Skjaldbreiður", an Icelandic shield volcano whose name means "broad shield," from its resemblance to a warrior's shield. Shield volcanoes are formed by lava flows of low viscosity — lava that flows easily. Consequently, a volcanic mountain having a broad profile is built up over time by flow after flow of relatively fluid basaltic lava issuing from vents or fissures on the surface of the volcano. Many of the largest volcanoes on Earth are shield volcanoes. The largest is Mauna Loa on the Big Island of Hawaii; all the volcanoes in the Hawaiian Islands are shield volcanoes. Shield volcanoes can be so large that they are sometimes considered to be a mountain range, such as the Ilgachuz Range and the Rainbow Range, both of which are located in Canada. These shield volcanoes formed when the North American Plate moved over a hotspot similar to the one feeding the Hawaiian Islands, called the Anahim hotspot. There are also shield volcanoes, for example, in Washington, Oregon, and the Galapagos Islands. The Piton de la Fournaise, on Reunion Island, is one of the more active shield volcanoes on earth, with one eruption per year on average.

The viscosity of magma as it approaches the surface is dependent on its temperature and composition. Shield volcanoes in the Hawaiian Islands erupt magma as hot as 1,200 °C (2,200 °F), compared with 850 °C (1,560 °F) for most continental volcanoes, which are usually composed of acidic lava. Because of the fluidity of the lava, major explosive eruptions do not occur. The most severe explosions occur if water enters a vent, although expanding gases in the magma can produce spectacular fountaining of the low viscosity lava.

Shield volcanoes are known to form on other planets. The largest known mountain in the solar system, Olympus Mons on Mars, is a shield volcano thought to be extinct. Shield volcanoes on Mars are higher and much more massive than those on Earth, likely due to lack of tectonic plates on Mars.

On Earth, because of plate tectonics, hotspot volcanoes eventually move away from the source of their magma and the volcanoes are individually less massive than might otherwise be the case. Shield volcanoes usually occur along constructive boundaries or above hotspots. However, the numerous large shield volcanoes of the Cascades of northern California and Oregon are over a more complex environment.

A cinder cone or scoria cone is a steep, conical hill of volcanic fragments that accumulate around and downwind from a volcanic vent.[1] The rock fragments, often called cinders or scoria, are glassy and contain numerous gas bubbles "frozen" into place as magma exploded into the air and then cooled quickly.[1] Cinder cones range in size from tens to hundreds of meters tall.[1]

Many cinder cones have a bowl-shaped crater at the summit. Lava flows are usually erupted by cinder cones, either through a breach on one side of the crater or from a vent located on a flank.[1] If the crater is fully breached, the remaining walls form an amphitheatre or horseshoe shape around the vent. Lava rarely issues from the top (except as a fountain) because the loose, uncemented cinders are too weak to support the pressure exerted by molten rock as it rises toward the surface through the central vent.[1]

B) Cinder cones are commonly found on the flanks of shield volcanoes, stratovolcanoes, and calderas.[1] For example, geologists have identified nearly 100 cinder cones on the flanks of Mauna Kea, a shield volcano located on the Island of Hawai`i.[1] These cones are also referred to as scoria cones and cinder and spatter cones.[1]

Perhaps the most famous cinder cone, Paricutin, grew out of a corn field in Mexico in 1943 from a new vent.[1] Eruptions continued for 9 years, built the cone to a height of 424 meters, and produced lava flows that covered 25 km².[1]

The Earth's most historically active cinder cone is Cerro ***** in Nicaragua.[1] It is part of a group of four young cinder cones NW of Las Pilas volcano.[1] Since it was born in 1850, it has erupted more than 20 times, most recently in 1992 and 1995.[1]


that should do it....

Answer 2

http://pirate.shu.edu/~schoenma/volcanoes.htm#shield these are images of the different kinds of volcanoes with a diagram for each one. good site for visual learners

Cinder cones- are simple volcanoes which have a bowl-shaped crater at the summit and only grow to about a thousand feet, the size of a hill. They usually are created of eruptions from a single opening, unlike a strato-volcano or shield volcano which can erupt from many different openings.