Do shield volcanoes have mild or steep slopes?

Do shield volcanoes have mild or steep slopes?

Shield volcanoes are composed almost entirely of relatively thin lava flows built up over a central vent. The low viscosity of the magma allows the lava to travel down slope on a gentle slope, but as it cools and its viscosity increases, its thickness builds up on the lower slopes giving a somewhat steeper lower slope.

Are shield or composite volcanoes steeper?

Composite cone volcanoes are also called stratovolcanoes. Alternating eruptions of volcanic ash and lava cause layers to form. Over time these layers build up. The result is a cone that has a gentler slope than a cinder cone but is steeper than a shield volcano.

What volcanoes are steep?

Stratovolcanoes have relatively steep sides and are more cone-shaped than shield volcanoes. They are formed from viscous, sticky lava that does not flow easily. The lava therefore builds up around the vent forming a volcano with steep sides.

Which is the best description of a shield volcano?

Shield volcano. Where a volcano produces low viscosity, runny, lava it spreads far from the source forming a volcano with gentle slopes. This type is called a shield volcano. Most shield volcanoes are formed of fluid basaltic lava flows. Mauna Kea and Mauna Loa are shield volcanoes.

What kind of volcano has a steep slope?

An eruption of highly viscous (very sticky) magma tends to produce steep-sided volcanoes with slopes that are about 30–35°. That’s because the viscous volcanic material doesn’t flow that far from where it is erupted, so it builds up in layers forming a cone-shaped volcano known as a stratovolcano.

How tall are shield volcanoes in California and Oregon?

Typical shield volcanoes present in California and Oregon measure 3 to 4 mi (5 to 6 km) in diameter and 1,500 to 2,000 ft (500 to 600 m) in height; shield volcanoes in the central Mexican Michoacán–Guanajuato volcanic field, by comparison, average 340 m (1,100 ft) in height and 4,100 m (13,500 ft) in width, with an average slope angle of 9.4

Which is the most active shield volcano in Africa?

The most active shield volcano in Africa is Nyamuragira. Eruptions at the shield volcano are generally centered within the large summit caldera or on the numerous fissures and cinder cones on the volcano’s flanks.