1) Tigres ;
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2) Euphrates .
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Answer:
Options (A), (C), (D) and (E)
Explanation:
The tectonic setting usually refers to the plate tectonic activity, where the earth's crust is divided into numerous small and large plates that move over the layer of the asthenosphere. This motion of plates gave rise to the formation of different geological settings on and under the earth's surface.
Some of the common tectonic activities that are associated with the volcanic activity are as follows-
- Continental rift refers to the splitting of the continental areas, where the rift valley is formed eventually and due to this divergent motion of the crust, there form volcanoes in the adjacent side of the plate boundary.
- Mantle plumes refer to the region where the hot and less dense magma rises up from the interior of the earth, forming large convection cells in columns. When plates move over this region, there form volcanoes. For example, Hawaii.
- Island arcs and continental arcs are commonly formed in the convergent plate boundaries, where the subduction zone is formed and as the magma rises upwards towards the surface in the over-riding plate, it forms volcanoes.
Thus, the correct answers are options (A), (C), (D) and (E).
Lake Victoria. Lake Victoria, also called Victoria Nyanza, largest lake in Africa and chief reservoir of the Nile, lying mainly in Tanzania and Uganda but bordering on Kenya. Its area is 26,828 square miles (69,484 square km).
