Question

mid - unit test, part 2
answer the questions below. when you are finished, submit this assignment to your teacher by the due date for full credit.

1. the diagram below shows three plates (a, b, c). plate b is denser than plates a and c. a continent is shown on plate c, along with seafloor. the other plates are entirely seafloor. the arrows show the directions that the plates are moving.

complete the table. first, note the geologic feature(s) that corresponds to each number on the map. then explain in detail how the plate movements at each location account for the features at that location.
symbols
island
mountain
volcano
rift valley
trench
answer

number on map	feature(s)	explanation
2

Explanation:

Step1: Analyze location 1

Plate A and Plate B are converging. Ocean - ocean convergence occurs here. The denser Plate B subducts beneath Plate A. As it subducts, melting occurs in the mantle above the subduction zone. Magma rises to the surface, forming a chain of islands and volcanoes.

Step2: Analyze location 2

This is an ocean - ocean subduction zone. Plate B is denser and subducts beneath Plate A. The subduction creates a deep - ocean trench. The melting of the subducting plate material gives rise to volcanic activity along the trench, forming the volcanic islands seen near the trench.

Step3: Analyze location 3

This is a divergent boundary between Plate A and Plate C. As the plates move apart, magma rises from the mantle to fill the gap. This creates a rift valley and new oceanic crust is formed.

Step4: Analyze location 4

This is a subduction zone where Plate B subducts beneath Plate C. The subduction of Plate B into the mantle causes melting. Magma rises and forms volcanoes on Plate C. The subduction also creates a trench along the boundary.

Step5: Analyze location 5

Plate C is a continental plate. The subduction of Plate B beneath Plate C causes compressional forces. These forces lead to the uplift and formation of mountains. The volcanic activity due to subduction also contributes to the mountain - building process.

Answer:

Number on Map	Feature(s)	Explanation
2	Trench, Islands and Volcanoes	Ocean - ocean subduction of Plate B beneath Plate A creating a trench and volcanic activity
3	Rift Valley	Divergent boundary between Plate A and Plate C, magma rising to form new crust and rift valley
4	Trench and Volcanoes	Subduction of Plate B beneath Plate C, causing melting and formation of volcanoes and a trench
5	Mountains and Volcanoes	Subduction of Plate B beneath continental Plate C, compressional forces and volcanic activity leading to mountain formation