Geysers

A geyser (pronounced gy-zuhr) is a geothermal feature. Geysers occur where there is an opening or fracture in the surface of the Earth. The opening contains superheated water that periodically erupts in a shower of water and steam. The word geyser is the only Icelandic word in the English language. It stems from the name of a particular geyser in southwest Iceland, the great Geysir (an Icelandic word meaning to gush or rush forth).


Steamboat Geyser in steam phase on May 2, 2000 at 10:00 AM (5:00 AM eruption); Norris Geyser Basin; NPS photo (Tom Cawley)

 

Geysers are rare. According to Geyser World there are approximately 1000 active geysers in the world, with about 500 of them being in Yellowstone National Park. For a listing of active, dormant and exinct geyser one should visit Johnston's Archive Geyser Resources.

In order for a geyser to form, three conditions must be met:


1. an abundant supply of water

2. a heat source

3. special plumbing

The problem is the special plumbing. Most geysers are found in the volcanic rock rhyolite, a high silica rock. Fields of rhyolite are rare hence geysers are rare. The site, “Geyser World”, goes on to give a readable explanation of what happens before and during an eruption. Geysers and the Earth's Plumbing System also explains what factors are needed for a geyser to exist and how a geyser erupts. Some of the links on this page do not work but it is well worth a visit. A cross-sectional diagram illustrates the three conditions that must be met to get geyser activity - heat, water and a reservoir. There are pictures of six basic type of plumbing systems that a geyser might have. The discussion after that gets more scientific in nature.

I have seen WyoJones' Geyser site referred to as the best geyser site on the web. There is a lot of useful information, most notably a section on the continuing survival of geysers. Geysers are temporary geological features. Many factors (either natural or man made) can alter or destroy them. Here, one can find out what dangers geysers have faced and what the greatest threat to their existence is right now. There is a list of geyser that have been damaged or destroyed. It is really a shame.

Is it possible to visit a geyser online? Sure! And where else would one go but to Yellowstone National Park. This is a great site. The tour starts with a visit to the various basins. A geyser basin is just an area that contains a group of geysers. After having finished strolling around the basins, it continues on stopping at each geyser individually. There are movies showing each geyser erupting. Or, one can visit National Park Service's Yellowstone National Park and take in the online nature tours.


Old Faithful Geyser; Upper Geyser Basin; NPS Photo (Jim Peaco)



The underlying geological feature of Yellowstone National Park is a caldera. For a definition of the word caldera visit USGS’s Photo Glossary of Volcanic Terms . For more information on calderas, not only in Yellowstone Park but around the world, one can visit USGS site Calderas and Caldera Formation.


Yellowstone Caldera map

A great site for kids is Making Better Sense of the Planet Earth and Beyond. Here, one can learn how to make his/her own geyser.

Lastly, the site Inside Old Faithful gives an account of what scientists saw when they lowered a camera down inside. Unfortunately, one thing they did discover was that the hot water was depositing silica on the walls of the vent. Old Faithful will eventually become clogged and will die. Let's hope that fate is a long ways in the future.

Standard Model

What are the smallest constituents or basic building blocks of all matter? Or, in scientific terms, what are the elementary or fundamental particles of matter? The words "elementary" and "fundamental" mean that the particle has no substructure. It cannot be broken down further into its constituent parts. Originally, it was thought that the atom was a fundamental particle, but it was discovered that atoms are made up of electrons and a nucleus. And, the nucleus is made up of protons and neutrons. So is that it? Can protons, electrons and neutrons be broken down further? The electron is still considered an elementary particle. Protons and neutrons were found to have substructure. Presently, there are 12 fundamental particles divided into two classes - leptons and quarks.

Within the lepton class, there are 6 fundamental particles - electron, muon, tau, electron neutrino, muon neutrino, tau neutrino.

Within the quark class, there are 6 fundamental particles - up quark (u), down quark (d), charm (c), strange (s), top quark (t), bottom quark (b).

The Fermilab's site, "Searching for the Building Blocks of Nature", relates how they discovered the top and bottom quark. The site talks about the accelerators and detectors needed, other technologies such as MRI (Magnetic Resonance Imaging) developed as a result of this research and their ongoing search for fundamental particles and forces.


All matter within the world is made up of three of these particles - the electron, up quark and down quark. Electrons, protons (u,u,d quark triplet) and neutrons (d,d,u quark triplet) combine to form atoms and molecules. The siteAtom builder illustrates how electrons, up quarks, and down quarks combine to make an atom, in this case a carbon atom. Building an atom is not easy.


So, what holds it all together? There are four elementary forces or interactions between particles - strong (hold the quarks together to form neutrons and protons), weak (help heavy particles to decay), electromagnetic (holds electrons to atomic nucleus) and gravitational. The particles interact with one another via "force carrying particles" called bosons. There are 4 bosons.

1. Gluons (nuclear force)

2. Photons (electromagnetic force)

3. W and Z bosons (weak force)


This is the "Standard Model of Particle Interaction" (or Standard Model - as it stands) - 6 quarks, 6 leptons and 4 bosons. Particle Physics Timeline (or Timeline ) illustrates the development of ideas from 624 B.C. to the present that led to the Standard Model. But it is not the end of the story. The quest goes on.

Impact craters

An impact crater is a site on a planet (i.e. Earth, Mars) or satellite (i.e. Moon) where a meteorite, comet or asteroid crashed. The following article will be concerned specifically with terrestrial (Earth) impact craters.


Artist's impression of a major impact event. 

Terrestrial Impact Craters , part of the Lunar and Planetary Institute's web site, gives a good overview into the subject. Here, one will find that there are presently about 120 identified impact craters on earth. It is felt that in all probability there are many more but due to erosion, volcanic and tectonic activity, traces of them have been erased. So, how does one identify an impact crater? According to the LPI site, certain shock metamorphism structures have been associated with impact sites:

* an abundance of siderophile elements

* shatter cones

* shocked quartz

* diaplectic glass

* high-pressure mineral phases such as stishovite


Extremely high pressure produces shock effects. (On the site MIAC one will find a picture and an explanation of how shatter cones are formed. The site states that the presence of shatter cones is sure evidence of an impact since the only other way that they can form is by nuclear explosion. Next, there is a picture of the feldspar mineral plagioclase , part of which has been changed to diaplectic glass, which happens at high pressure. There is also a picture of shocked quartz. Quartz does not show cleavage planes ordinarily but under high pressure can form parallel pseudo-cleavage planes, another indication that an impact has occurred.) Stishovite or silicon dioxide (SiO₂) forms at very high pressures but not necessary high temperatures, the exact conditions that would exist at an impact site. Siderophile (having an affinity for metallic iron or iron-like ) elements (iron, cobalt, nickel, gold and palladium) are found most abundantly in the earth's core. (Observed relative abundances of elements gives a brief discussion of how elements separate out in a gravitational field.) It is therefore theorized that a high concentration of siderophile elements at the earth's surface is probably due to an extra-terrestrial source, such as a meteorite.

Now that one know how to identify an impact site, what does an impact crater look like? The site Terrestrial Impact Craters identify two types of crater - simple craters and complex craters. Complex craters are characterized by a central peak, which forms when the crater floor rebounds from the initial impact. Crater Formation shows a possible scenario for the formation of a complex crater.

Another interesting site is Impact Craters, part of the University of Hawaii's web site. Although the site is about impact crater on the moon, one can use this site to learn some "crater" jargon. Terms such as impactor, ejecta, rays and central uplift are defined and illustrated.

Where are these impact craters and approximately when did the impacts take place? Terrestrial Impact Craters , lists 20 terrestrial impact sites with great pictures and short descriptions. The NASA's site Exploration features a map of the earth with the positions of various craters marked. There is a sliding scale at the bottom allowing one to go back approximately 1970 million years then move forward to see the order of impact. Additional information on locating impact craters can be found in the Earth Impact Database . This site hosts a database listing all known terrestrial impact structures.

After having learnt so much about impact craters, a visit to one would seem to be in order. How about Meteor Crater a.k.a. Barringer Meteorite Crater in Arizona? One can read about the history of the crater then take the virtual tour around the rim. After getting back from the tour, one can view the animation of the impact. Anyone wishing to discover more about the Barringer Meteorite Crater can drop by their official site . There is a super article about how it was determined that the Barringer Crater was indeed an impact site.


Barringer Crater in Arizona 


Finally, the site National Geographer's Asteroids-Deadly Impact is worth a visit. One can become an agent and solve the mysterious cases of the extraterrestrial perpetrators :-).

Glaciers

What are glaciers? Where do they occur? Why are they of interest? Want to find out?


The Upper Grindelwald Glacier and the Schreckhorn


First stop is an up-to-date site by the National Snow and Ice Data Center (NSIDC) . What is a glacier? Quoting from the site: "...Glaciers are made up of fallen snow that, over many years, compresses into large, thickened ice masses. Glaciers form when snow remains in one location long enough to transform into ice”…. How do they form or why do they move? You are going to have to visit the site to find out. The pictures on this site are in black and white. But don't let that bother you. Some are historical photos dating back to the 1880's. If you find a glacier-related term that you are unfamiliar with, look it up in the glossary. In a hurry? Take the glacier tour for a quick look at the life of a glacier. Phew! That's a lot for one web site. Hope you are not tired. Are you ready to move on?


Formation of glacier ice.

Glacier Power is a site you will enjoy. Your guides are the ice worms Joe, Lady Loo, Gene the Bean, Nick the Nerd, Little Joe, Dr. Daisy, Grammy Lynn. Ice worms live on glaciers eating a diet of algae and pollen. Glacier Power is a learning site for students aged 5 to 12. The pages center on Miner Ed who accidentally falls into a glacial crevice. Poor Ed. Now, it's up to you to determine if and when Miner Ed will emerge from the terminus of the glacier. How do you do that? Well first, read through the site to learn about glaciers. Then, using this information and Synthetic Aperture Radar (SAR) Satellite Images of glaciers, work out if and when Ed will pop out of the glacier. Good thing they help you read the images, otherwise I would have been stuck. And don't worry, Ed gets out. This site is a great educational resource.


Now that you know something about glaciers, how about visiting one? Let's surf on up to Glacier Bay in Alaska which boasts over 200 separate glaciers. This is an unbelievable site. Of course, all NASA sites are unreal. To enjoy it properly you will need a program that plays QuickTime movies. The tour is a long one, so be prepared to stay awhile. First stop, pictures of the spectacular glaciers of Glacier Bay, maps of the area, historical photographs, and satellite images of various glaciers. Don't linger too long. On to the movies where two features are playing: spectacular fly-bys over glaciers and the special effects theatre. The fly-bys were made using satellite images and computer techniques. The tour then continues on to discuss how satellite data can be combined with historical records to track glacier movement and possibly show how climate change affects glaciers and how glaciers might be able to be used as indicators of climate change.

If you would like to visit a glacier in person, try The Inquisitive Traveler . It provides information about accessible glaciers in North America. Glaciers can be found in Alaska, Western Canada, Montana, Oregon and Washington State. If you want to know about glaciers in other parts of the world, visit the World Glacier Inventory by the University of Colorado. It lists over 67,000 glaciers.