Fill In The Blank: Lava With A Higher Content Of Has Higher

Fill In The Blank1 Lava With A Higher Content Of Has Higher

Fill in the blank. 1. Lava with a higher content of _______ has higher viscosity. 2. If a large explosion causes the magma chamber below a volcano to empty, the volcano can collapse and form a/an _______. 3. Shield volcanoes can form when less _______ lava flows quickly away from a vent.

Respond to the following based on your reading. 4. Briefly describe what causes a volcanic eruption to be explosive. 5. When magma solidifies underground, the resulting landform is classified as _______. 6. Lava cooling on the surface of the earth forms _______ features. 7. A very large mineral is more likely to be found in _______ rock. 8. _______ is magma that forms in long, horizontal shafts in the earth’s crust. 9. Lava with high basalt content forms _______ through multiple eruptions.

Respond to the following based on your reading. 10. How can an intrusive landform become exposed to the air and visible? Fill in the blank. 1. During an oceanic plate convergence, the _______ plate will sink. 2. The West Coast of the United States has features formed by _______. 3. During the _______ of two tectonic plates, magma fills the space between the plates. 4. The only volcanic activity that's not formed at tectonic plate boundaries is _______.

Respond to the following based on your reading. 5. Why does underwater hot-spot volcanism tend to form chains of islands? For that matter, why doesn't it form one huge, single island?

Sample Paper For Above instruction

Volcanic activity is a fundamental geological process that shapes the Earth's surface and influences its environment. The properties of lava, the formation of landforms, and the mechanisms behind eruptions are vital to understanding volcanic phenomena. Lava with a higher content of silica (silicon dioxide) has higher viscosity. Silica-rich magmas tend to be thick and sticky, which causes gases to become trapped more readily, leading to explosive eruptions. Conversely, basaltic lava with low silica content flows more easily due to its low viscosity, resulting in less explosive activity.

The collapse of a volcano following a significant eruption occurs when the magma chamber empties rapidly. This can cause the overlying structure to become unstable, collapsing into a crater or caldera below. Shield volcanoes are characterized by their broad, gentle slopes and are formed by low-viscosity basaltic lava that allows gases to escape easily, enabling lava to flow quickly over large areas. These eruptions are typically non-explosive because of the low silica content, which reduces the likelihood of gas buildup.

A landform resulting from underground solidification of magma is called an intrusive igneous feature, such as a batholith or sill. These features are often exposed over time due to erosion of the surrounding softer rock layers. Lava cooling on the surface can produce features like lava plains, plateaus, and volcanic islands. Large mineral deposits are more commonly associated with plutonic, or intrusive, rocks that cool slowly, allowing crystals to grow large enough to be mined efficiently.

Magma that forms in long, horizontal underground chambers is known as a sill. Lava with high basalt content, typically characterized by low viscosity, forms extensive lava plateaus through numerous eruptions. These features result from repeated lava flows that build up over time, creating large, flat volcanic landscapes. Intrusive landforms become visible when overlying rocks are eroded away, exposing the solidified magma beneath.

During oceanic plate convergence, the denser oceanic plate sinks beneath the continental plate, leading to subduction zone volcanism. The West Coast of the United States is shaped significantly by subduction processes, resulting in mountain ranges like the Cascades. When two tectonic plates diverge, magma rises from the mantle to fill the space, creating new crust—this process commonly occurs at divergent boundary zones such as mid-ocean ridges. Volcanic activity that occurs away from plate boundaries, such as hot-spot eruptions (e.g., Hawaiian Islands), is not directly associated with plate movements but results from mantel plumes.

Underwater hot-spot volcanism tends to form chains of islands because as the tectonic plates move over stationary mantle plumes, sequential eruptions create a series of volcanoes that eventually rise above sea level. This movement explains why hot-spot chains, like the Hawaiian Islands, stretch in the direction of plate movement rather than forming a single massive island.

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