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Task 3. Copy out all the proper nouns (geographical names) from the text in
Task 2. Try to define the geographical position of all the mentioned objects on the
map. Transcribe the proper nouns.

Task 4. Look at Figure 8.2, A and B. Describe and discuss:
 the three ways of the global distribution of volcanism;
 convergent plate volcanism (island arc);
 divergent plate volcanism (oceanic ridge).

Individual work

Task 1. Read the text and translate it into Ukrainian (in written form).
Build up a list of key terms to the text. While reading have a look at Figure 8.3: A,
B and C. The figure shows the model of hot-spot volcanism thought to explain the
formation of oceanic plateaus and the volcanic islands associated with these
features. A. A rising mantle plume with large bulbous head and narrow tail. B.
Rapid decompression melting of the head of a mantle plume produces vast
outpourings of basalt to generate the oceanic plateau. Large basaltic plateaus can
also form on continental crust—examples include the Columbia Plateau in the
north-western United States and India’s Deccan Plateau. C. Later, less voluminous
activity caused by the rising plume tail produces a linear volcanic chain on the
seafloor.

Most intraplate volcanism (meaning “within the plate”) occurs where a mass of
hotter than normal mantle material called a mantle plume ascends toward the surface.
Although the depth at which mantle plumes originate is still hotly debated, some appear
to form deep within Earth at the core–mantle boundary. These plumes of solid yet
mobile mantle rock rise toward the surface in a manner similar to the blobs that form
within a lava lamp. Like the blobs in a lava lamp, a mantle plume has a bulbous head
that draws out a narrow stalk beneath it as it rises. Once the plume head nears the top of
the mantle, decompression melting generates basaltic magma that may eventually
trigger volcanism at the surface.
The result is a localized volcanic region a few hundred km across called a hot
spot. More than 40 hot spots have been identified, and most have persisted for millions
of years. The land surface surrounding a hot spot is often elevated because it is buoyed
up by the rising plume of warm low-density material. By measuring the heat flow in
these regions, geologists have determined that the mantle beneath hot spots must be 100
to 150 °C hotter than normal mantle material.
Mantle plumes are responsible for the vast outpourings of basaltic lava that
created the large basalt plateaus including the India’s Deccan Plateau, and the Ontong
Java Plateau in the western Pacific. The most widely accepted explanation for these
eruptions, which emit extremely large volumes of basaltic lava over relatively short
time intervals, involves a plume with a monsterous head and a long, narrow tail
(FIGURE 8.2, A). Upon reaching the base of the lithosphere, these unusually hot,
massive heads begin to melt. Melting progresses rapidly, causing the burst of volcanism
that emits voluminous outpourings of lava to form a huge basalt plateau in a matter of a
million or so years (FIGURE 8.2, B). The comparatively short initial eruptive phase is
followed by tens of millions of years of less voluminous activity, as the plume tail
slowly rises to the surface. Extending away from most large flood basalt provinces is a
chain of volcanic structures, similar to the Hawaiian chain that terminates over an active

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