Yellowstone national park

Question 1

Facts

Answer 1

Yellowstone contains around 10,000 thermal features including geysers, fumaroles, hot springs and boiling mud.

Causes of the thermal features:
There are three main causes for the thermal features:
Heat source
Water
Rock type and minerals

Question 2

Geysers:

Answer 2

At Yellowstone the crust is less than 40 miles thick whereas at most other land areas the crust is 90 miles thick. Intruded into this crust is magma plutons. These are typically located at a depth of four to ten miles. A transition zone exists between the hot molten magma and the crust. This pliable layer of partially molten crystalline rock is close to its melting point. Water filters through, fissures, cracks and porous rock and is heated by the molten crystalline rock to a temperature above its surface boiling point. Due to the pressure in the underground network, it doesn’t boil. Pressure is eventually released as the superheated water works its way up through the subterranean chambers. It then traps the superheated water before it reaches the surface and cools. Near the surface when the pressure is suddenly released, boiling explosions occur, forming steam. This can form two types of geysers: cone and fountain geysers, depending on the plumbing system.

Question 3

Cone geysers:

Answer 3

These generally have a narrower constriction close to the geyser’s vent. During eruptions the constriction acts like a nozzle, causing the water to jet into columns. The cone is formed through the deposition of silica. While travelling underground through volcanic rhyolite, the thermal water dissolves the silica, then carries it to the surface. As a result, a portion may be deposited around the outside of a geyser to form a distinctive cone. The splashing of silica-rich thermal water may also form spiny, bulbous masses of “geyserite.”
An example is Beehive geyser.

Question 4

Fountain geysers:

Answer 4

Fountain geysers, such as Great Fountain in the Lower Geyser Basin, shoot water in various directions, typically from a pool. A fountain-type geyser has a large opening at the surface that usually fills with water before or during an eruption. Steam bubbles rising through the pool during the eruption cause separate bursts of water that generally spray out in all directions. Fountain type geysers are the most common type of geyser and can range in size from very small to very large.

Question 5

Fumaroles

Answer 5

The hottest of Yellowstone’s geothermal features are steam vents (fumaroles). Black Growler Steam Vent has measured 199 to 280 degrees F (93 to 138 degrees C). Located in Norris Geyser Basin, Black Growler is one of Yellowstone’s most famous steam vents. This feature has a history of shifting its location several times. It has been active since 1878 at least, often roaring in a noisy stream of hot vapor.

Question 6

Boiling mud:

Answer 6

In a mud pot, surface water collects in a shallow, impermeable (usually due to a lining of clay) depression that has no direct connection to an underground water flow. Thermal water beneath the depression causes steam to rise through the ground, heating the collected surface water. Hydrogen sulfide gas is usually present, giving mud pots their characteristic odor of rotten eggs. Some microorganisms use the hydrogen sulfide for energy. The microbes help convert the gas to sulfuric acid, which breaks down rock into clay. The result is a gooey mix through which gases gurgle and bubble.

After coming upon Mud Volcano during his 1871 expedition to Yellowstone, Ferdinand Hayden described the mudpot as “the greatest marvel we have met with.”

Question 7

Hot springs:

Answer 7

In Yellowstone, hot springs, pools, and run-off channels exhibit all colors of the rainbow. Bacteria and algae are mainly responsible for brightly colored runoff channels which occur at various locations based on temperature.
The Sulphur Caldron area can be viewed from a staging area just north of Mud Volcano. The Sulphur Caldron is among the most acidic springs in the park with a pH of 1.3.