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rock and lava fragments blown from the volcano’s vent, which include ash, pumice, …
, cinders, blocks, and bombs).

Unit 8
VOLCANIC STRUCTURES AND ERUPTIVE STYLES
Part 2
Task 1. Read and memorize the following words:
collapse pit – кратер вулкану colossal - величезний
plug - пробка, заглушка; екструзивний connect – з’єднувати
бісмаліт
сaldera - кальдера drainage - дренаж
weathering – вивітрювання, ерозія lower – зменшуватись, знижуватись
squeeze – вичавлювати, видавлювати pancake-like – подібний на млинець,
оладку
steep-sided – той, що має круті або piston - поршень
обривчасті сторони
unconsolidated – пухкий, неущільнений succumb – не витримати, поступитися
subterranean - підземний toblanket - покривати
diatreme - діатрема undergo - піддаватися
resistant – стійкий, міцний vanish - зникати

Task 2. Read the following text, translate it into Ukrainian.

Other Volcanic Landforms
The most obvious volcanic structure is a cone, but other important landforms are
also associated with volcanic activity.
Calderas (caldaria = a cooking pot) are large depressions with diameters that
exceed 1 km and have a somewhat circular form. (Those less than 1 km across are
called collapse pits or craters.) Most calderas are formed by one of the following
processes: (1) the collapse of the summit of a large composite volcano following an
explosive eruption of silica-rich pumice and ash fragments (Crater Laketype calderas);
(2) the collapse of the top of a shield volcano caused by subterranean drainage from a
central magma chamber (Hawaiian-type calderas); and (3) the collapse of a large area,
caused by the discharge of colossal volumes of silica-rich pumice and ash along ring
fractures (Yellowstone-type calderas).
The greatest volume of volcanic material is extruded from fractures in the crust
called fissures (fissura = to split). These long, narrow cracks tend to emit low-viscosity
basaltic lavas that blanket a wide area.
In contrast to mafic lavas, silica-rich felsic lavas are so viscous they hardly flow
at all. As the thick lava is “squeezed” out of the vent, it often produces a dome-shaped
mass called a lava dome. Most lava domes are only a few tens of meters high, but some
are more than 1 km high. Lava domes come in a variety of shapes that range from
pancake-like flows to steep-sided plugs that were pushed upward like pistons. Most
develop over a period of several years following an explosive eruption of gas-rich
magma. A recent example is the dome that continues to grow in the crater of Mount St.
Helens. A second dome building event began in October 2004. Although lava domes
often form on the summit of a composite cone they can also develop on the flanks of
volcanoes. In addition, some domes occur as isolated features, whereas others form
linear chains.
Most volcanoes are fed magma through short conduits, called pipes that connect
a magma chamber to the surface. One rare type of pipe, called a diatreme, extends to
depths that exceed 200 km. Magmas that migrate upward through diatremes travel

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