Question

$$ \begin{aligned} &\text { Use the table below to answer questions 12-14. }\\\ &\begin{array}{|c|c|} \hline \text { Eruption } & \begin{array}{c} \text { Volume Percent } \\ \text { Water Vapor } \end{array} \\ \hline 1 & 58.7 \\ \hline 2 & 60.1 \\ \hline 3 & 61.4 \\ \hline 4 & 59.3 \\ \hline 5 & 59.6 \\ \hline \end{array} \end{aligned} $$ The water vapor content of Kilauea is above average when compared to other volcanoes. How might these data help to explain why lava fountains often occur on Kilauea?

Short answer

High water vapor content increases gas pressure, leading to lava fountains on Kilauea.

Step-by-step solution

Review Data Table

Examine the table provided, which shows the volume percent of water vapor for five eruptions. The values listed are 58.7%, 60.1%, 61.4%, 59.3%, and 59.6%.

Determine Average Water Vapor

Calculate the average water vapor content from the given eruptions. Add all the percentages and divide by the number of eruptions: \( \frac{58.7 + 60.1 + 61.4 + 59.3 + 59.6}{5} = 59.82\% \).

Analyze Water Vapor Content

Compare the average water vapor content (59.82%) with general volcanic water vapor content data. Given that Kilauea's water vapor content is above average, this suggests that its levels are relatively high.

Understand Lava Fountain Mechanism

Higher water vapor content in volcanic eruptions can lead to increased gas pressure. This pressure builds up beneath the surface, often resulting in the explosive behavior of lava fountains.

Connect Data to Lava Fountains

Since Kilauea's water vapor content is above average, this high volume of water vapor can create sufficient pressure for lava fountains, explaining their frequent occurrence on this volcano.

Key concepts

Kilauea volcano

Kilauea is a prominent volcano located in Hawaii. Famous for its frequent eruptions, it plays a vital role in the Island's landscape formation. Kilauea is a shield volcano, characterized by its broad and gently sloping shape.
Its eruptions are known for producing flows of basaltic lava, which tend to be less viscous than lava from other volcano types.
This means the lava can spread over long distances. Kilauea's active lava flows and eruptions have drawn both scientific interest and tourists worldwide.
As part of the Hawaii Volcanoes National Park, it is recognized as one of the world's most active volcanoes, with eruptions occurring frequently throughout recent history.
Its persistent activity makes it a critical focus for volcanic research, providing opportunities to study eruption patterns, predict future activity, and understand the impacts on nearby communities.

lava fountains

Lava fountains are spectacular volcanic events where molten lava is ejected high into the air from a central vent. They resemble a fountain of fire, displaying vivid red and orange colors.
The height of lava fountains can vary greatly, from a few meters to several hundred meters high, depending on various factors, such as gas content and eruption intensity.
These events are not only visually stunning but also carry scientific significance. They provide insights into the eruptive behavior of a volcano, particularly concerning the movement of magma.

• Increased gas content, especially water vapor, can lead to more vigorous fountaining.
• Pressure changes beneath the volcano play a key role in initiating these events.

For volcanoes like Kilauea, known for their above-average water vapor content in eruptions, lava fountains are a common feature.
They provide a dynamic demonstration of the powerful forces at work beneath the Earth's surface.

gas pressure in volcanoes

Gas pressure is a central element in volcanic eruptions. It originates from gases like water vapor, carbon dioxide, and sulfur dioxide trapped in the magma chamber.
As magma ascends towards the surface, the pressure decreases, allowing these gases to expand and separate from the molten rock.
This process can substantially increase the internal pressure within a volcano, sometimes leading to explosive eruptions.

• Water vapor is the most abundant gas in many volcanic eruptions, contributing to significant pressure buildup.
• When the pressure exceeds the strength of the overlying rock, it can result in a violent ejection of magma.
• Gas pressure is also instrumental in forming lava fountains by pushing lava high into the air.

Understanding the dynamics of gas pressure helps volcanologists predict eruption behaviors and potential hazards.
This knowledge can be crucial for evaluating risks associated with active volcanoes, like Kilauea.

volcanic eruption analysis

Volcanic eruption analysis is the scientific study and assessment of volcanic activity to understand the factors influencing eruptions. It involves observing, measuring, and modeling various eruption parameters such as gas emissions, lava flow, and explosive activity.
This analysis helps in predicting future eruptions and assessing the risks to populations living nearby.

• Data on water vapor content and other volcanic gases are critical for understanding eruption dynamics.
• High water vapor levels, as seen in Kilauea, are often associated with more intense eruption phenomena, such as lava fountains.
• Monitoring equipment around volcanoes captures real-time data that informs hazard assessments.

Eruption analysis applies a range of scientific techniques, including geology, chemistry, and physics, to build comprehensive models of volcanic behavior.
Such in-depth studies allow regions prone to volcanic activity to implement better safety protocols and mitigate potential impacts efficiently.