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I assume you mean "Chernobyls". More than that, actually. Coal mine accidents killed about 6000 (six thousands) people in 2004, the enormous majority in China. China is also the main coal supplier of the USA. Is that why coal is considered "safer than nuclear"? Because only some Chinese die?

It should also be noted that coal's carbon structure is a natural trap for heavy elements, especially uranides (thorium mostly), which is why you register a significant radiation level downwind from a coal-burning powered plant. You can wash the combustion output, but then you have to dispose acidic, radioactive sludge. Naaah. See this article.

But most of the pollution is not even coming from coal-burning plants, as explained in this article.. Excerpt: According to Stracher's forthcoming article in the "International Journal of Coal Geology," scientists have determined that coal fires in China consume up to 200 million tons of coal per year. For comparison, coal consumption in the United States during 2000 was just over one billion tons, according to the U.S. Department of Energy.

Since CO2 is formed by binding two oxygen atoms (molar wight 16) on each carbon atom (molar w. 12), 200 million tons of coal at 80% carbon form about 200* 0.8 * 16 * 2/ 12 = 427 million tons CO2. So when I hear well-meaning but clueless environmentalists worrying about cow farts while ignoring this huge problem, I know that whoever feeds them this disinformation has an agenda.

Seriously?

If the Earth is 5.4 billion years old and ice cores are unreliably accurate to 100,000 years, can you honestly say that we have a "fairly good indication" of how the earth has evolved? Ice cores are not even a blip (.00185%) on earth's timeline, nor is the "damage" we've caused.

Seriously?

If the Earth is 5.4 billion years old and ice cores are unreliably accurate to 100,000 years, can you honestly say that we have a "fairly good indication" of how the earth has evolved? Ice cores are not even a blip (.00185%) on earth's timeline, nor is the "damage" we've caused.

Kilauea volcano emits more than 700,000 tons of CO2 each year, less than 0.01% of the yearly global contribution by human sources. For some local perspective, this is about the same amount of CO2 as is emitted by 132,000 sport utility vehicles (there are 118,000 registered vehicles on the island).

According to US DOE EIA

U.S. greenhouse gas emissions in 2003 were ... 6,115.2 million metric tons carbon dioxide equivalent...

So that makes the volcanos:USA ratio about 1:6.

Does that help clarify?

Well, here's an overview of Cascade shield volcanoes.

Some of them are quite young. Belknap crater, which I have visited, has lava so young that few plants are growing on it. Newberry's last eruption was 2000 years ago.

Anyway, a lot of the basalt leans toward andesite, but there's a significant amount of good old mafic basalt. For shield volcanoes in the high cascades, one theory is that since the Juan de Fuca plate is subducting at such a low angle, that there is less continental crust for it to go through than other areas.

There is also a theory that there's a hot spot involved, located somewhere under Oregon. Newberry is sometimes cited as the shield volcano that is a result of hot-spot activity due to its location being fairly distant from the high Cascades. Since there tends to be a constant distance between subduction and volcanic activity, therefore must be a different mechanism involved. The idea is that some of the upwelling basalt has come through at newberry, and that some has been directed up the subduction zone, since it's a weak area, and becomes mixed in with the more felsic magma from the subduction zone.

So for the first theory, the shield volcanoes are exclusively ring-of-fire, for the second, both ring-of-fire and hot spot.

I'm not entirely up on all the other theories covering Cascades shield volcanoes, since I studied more structural geology and earth materials, but not vulcanology, but there are other theories out there from differentiated magma chambers to crustal composition theories.

I know it is out of the scope of this article but I think that Barrier Islands need to be talked about when talking of reducing the damage from Hurricanes.

http://www.nwrc.usgs.gov/hurricane/post-hurricane- katrina-photos.htm The Barrier Islands off the coast of Louisiana took a beating. However without them the damage on the coast could have been even worse.

• There are known perlites with apache tears in them in a couple of isolated areas. This would be chunks of obsidian in a relatively solid matrix.
• I suppose someone without much geology background could mistake large phenocrysts of magnetite or hornblende in a basalt as bits of glass, and hence assume obsidian.
• Mt. Mazama tephra and tuff (produced in the eruption that formed Crater Lake) has chunks of obsidian in it in places, quite often really degassed pumice embedded in an ash matrix. Occasionally this matrix is rather pink-red. This is also a candidate for the GP's observation.
• Sometimes there are phenocrysts of pyroxene and olivine in the basalt around Central Oregon, and the darker varieties could appear to be bits of glass in the basalt, to the untrained eye. If the GP was really looking at basalt and can't readily tell crystals from bits of glass, this would be a good explaination for the observation.

Who needs Google Maps when we have PIGWAD?

First, Ash does and can fall right out of the sky during an eruption, it is called a nuee ardente or pyroclastic flow. http://www.geo.mtu.edu/volcanoes/hazards/primer/py ro.html It happened at St. Helens and if the eruption is significant enough it will most likely produce one. It is more common than rare. If the eruption is big enough to cause this type of eruption, you can be assured that the ash can and often does reach into the upper limits of the atmosphere and can have a long term effect on the atmosphere and even cause climate changes and disrupt the ozone layer.

Second, volcanoes can develop quite rapily, Paricutin for example.http://vulcan.wr.usgs.gov/Volcanoes/Mexico /description_mexico_volcanoes.html

Third, Krakatoa's devopement was due to subduction and did have the high silicic lava that causes plugging, but the explosive event it created was due more to the ocean water getting into the crater that resulted from the huge amount of magma loss resulting in a collapse of the island. This ocean water was super heated and is called a phreatomagmatic erruption. This is what is thought to be mostly responsible for the resultant tsunami and destruction of Krakatoa.http://www.drgeorgepc.com/TsunamiVolcanic Mechanisms.html

Forth, As for Mars, there is no source for internal heating that drives the processes that lead to vulcanism anymore. The current belief is that the heat source is either to small or has cooled sufficiently to have ceased any geological surface processes. It has probably been more than 20 million years since a volcano has errupted on Mars.http://volcano.und.edu/vwdocs/planet_volcano/ mars/Overview.html

Fifth, As for igneous rock "not flexing" it is pretty flexible in the molten state. It is no less "flexible" than other rock types, metamorphic and sedimentary. Usually geologists discuss rocks in terms of hardness using the standard Mohs scale where talc is 1 and diamond is 10.http://geology.about.com/library/bl/blmohsscale .htm

I believe to retain credibility it is helpful to have facts straight before stating them.

I think you're looking for stratovolcano.

Yeah, it was kinda hard to find. Did a google search on shield volcano which took me to the USGS's site, which I figured was about the best authority. Hoped for a link on the page but couldn't find one, so took a wild chance and simply truncated the url to http://volcanoes.usgs.gov/Products/Pglossary/ which ended up working, and did a search on the page for the word volcano. Eventually came across stratovolcano and I was like "Yeah, that's the one."

I'm just glad the USGS doesn't disallow directory requests like so many commercial sites.

I think you're looking for stratovolcano.

Yeah, it was kinda hard to find. Did a google search on shield volcano which took me to the USGS's site, which I figured was about the best authority. Hoped for a link on the page but couldn't find one, so took a wild chance and simply truncated the url to http://volcanoes.usgs.gov/Products/Pglossary/ which ended up working, and did a search on the page for the word volcano. Eventually came across stratovolcano and I was like "Yeah, that's the one."

I'm just glad the USGS doesn't disallow directory requests like so many commercial sites.

A shield volcano is formed when a large pool of magma forms and pushes the land above it upwards. These types are not likely to erupt, though they will erupt violently if the magma is able to push through the surface (kind of like a giant geologic pimple). These volcanos are great for tourism because of the typically accompanying hot springs and year-round greenery.

Um, no. Not even close.

A shield volcano is formed by eruptions of basalt, a very fluid magma, creating a gently-sloping broad-based volcano.

For example, all the Hawaiian islands are shield volcanoes. Newberry caldera in Oregon is a shield volcano.

USGS info page on shield volcanoes.

I like Oregon a lot. I just wish it were easier to get to.

We make difficult on purpose.

Volcano lesson for the day:
This is not a shield volcano.

A shield volcano is actually made by layers and layers of basaltic magma. Hawaii (the large, flat volcanos) are shield volcanos. Basaltic magma is very hot, iron rich, and flows easily. It tends to bubble and gurgle, not explode. There's a reason hawaiian eruptions don't produce ash clouds - no big explosion.

http://volcanoes.usgs.gov/Products/Pglossary/Shiel dVolcano.html

In Oregon, we have very few shield volcanos. Most of ours are composite volcanos (made from lava pusing up a dome, plus layers of flowing ash) and cinder cones (made from piles of ejected cinders). Our magmas are rhyolitic, meaning they contain little iron, it is at relatively cooler temperatures, and tend to explode violently (like Mount St. Helens or the famous Mount Mazama... now crater lake).

http://vulcan.wr.usgs.gov/Glossary/StratoVolcano/d escription_composite_volcano.html

Volcano lesson for the day:
This is not a shield volcano.

A shield volcano is actually made by layers and layers of basaltic magma. Hawaii (the large, flat volcanos) are shield volcanos. Basaltic magma is very hot, iron rich, and flows easily. It tends to bubble and gurgle, not explode. There's a reason hawaiian eruptions don't produce ash clouds - no big explosion.

http://volcanoes.usgs.gov/Products/Pglossary/Shiel dVolcano.html

In Oregon, we have very few shield volcanos. Most of ours are composite volcanos (made from lava pusing up a dome, plus layers of flowing ash) and cinder cones (made from piles of ejected cinders). Our magmas are rhyolitic, meaning they contain little iron, it is at relatively cooler temperatures, and tend to explode violently (like Mount St. Helens or the famous Mount Mazama... now crater lake).

http://vulcan.wr.usgs.gov/Glossary/StratoVolcano/d escription_composite_volcano.html

Yeah, that's what I first thought upon reading this, too, since 100 square miles sounds pretty darn big. Then I looked it up, and realized that the Yellowstone caldera is an order of magnitude bigger (28 * 47 = ~1316 square miles), and that only includes the actual part where magma comes out. In comparison, this 100 square mile figure includes the entire area of uplift.

To put things into perspective here's recent quakes throught the US, notice the activity in the state of California, to the south.

Back in the late 90's there were swarms of minor earthquakes around the Long Valley Caldera, the vicinity of California where Mammoth Lakes and Mammoth Mountain are located. Swarms of earth quakes, 4.0 (Richter) and lower, most lower than 2.0, were up to 600 per 24 hours for a period of about two weeks, and ground elevations were observed changing (similarly to those in Oregon) slightly, but as you can see all is quiet and nothing happened. Long Valley is the caldera of a very large, dormant volcano.

Here is a good example of a swarm of aftershocks.

To put things into perspective here's recent quakes throught the US, notice the activity in the state of California, to the south.

Back in the late 90's there were swarms of minor earthquakes around the Long Valley Caldera, the vicinity of California where Mammoth Lakes and Mammoth Mountain are located. Swarms of earth quakes, 4.0 (Richter) and lower, most lower than 2.0, were up to 600 per 24 hours for a period of about two weeks, and ground elevations were observed changing (similarly to those in Oregon) slightly, but as you can see all is quiet and nothing happened. Long Valley is the caldera of a very large, dormant volcano.

Here is a good example of a swarm of aftershocks.

To put things into perspective here's recent quakes throught the US, notice the activity in the state of California, to the south.

Back in the late 90's there were swarms of minor earthquakes around the Long Valley Caldera, the vicinity of California where Mammoth Lakes and Mammoth Mountain are located. Swarms of earth quakes, 4.0 (Richter) and lower, most lower than 2.0, were up to 600 per 24 hours for a period of about two weeks, and ground elevations were observed changing (similarly to those in Oregon) slightly, but as you can see all is quiet and nothing happened. Long Valley is the caldera of a very large, dormant volcano.

Here is a good example of a swarm of aftershocks.

To put things into perspective here's recent quakes throught the US, notice the activity in the state of California, to the south.

Back in the late 90's there were swarms of minor earthquakes around the Long Valley Caldera, the vicinity of California where Mammoth Lakes and Mammoth Mountain are located. Swarms of earth quakes, 4.0 (Richter) and lower, most lower than 2.0, were up to 600 per 24 hours for a period of about two weeks, and ground elevations were observed changing (similarly to those in Oregon) slightly, but as you can see all is quiet and nothing happened. Long Valley is the caldera of a very large, dormant volcano.

Here is a good example of a swarm of aftershocks.

I wonder what ever became of the research on methane hydrates. That seemed like a promising source of hydrocarbons.

...and let the delta rebuild itself naturally.

If we were to let the delta rebuild itself naturally, then we would need to let the Mississippi flow where it wants. This means that the entire alluvial plain would need to be vacated. I seriously doubt that's going to happen.

Apparently you're woefully unaware that Lake Pontchartrain is (well, was) surrounded by wetlands on all sides. Oh, and in case you don't know what FEMA's job is and what they were *supposed* to be doing, here's a link:

DISASTER. It strikes anytime, anywhere. It takes many forms -- a hurricane, an earthquake, a tornado, a flood, a fire or a hazardous spill, an act of nature or an act of terrorism. It builds over days or weeks, or hits suddenly, without warning. Every year, millions of Americans face disaster, and its terrifying consequences.

On March 1, 2003, the Federal Emergency Management Agency (FEMA) became part of the U.S. Department of Homeland Security (DHS). FEMA's continuing mission within the new department is to lead the effort to prepare the nation for all hazards and effectively manage federal response and recovery efforts following any national incident. FEMA also initiates proactive mitigation activities, trains first responders, and manages the National Flood Insurance Program and the U.S. Fire Administration.

Certainly the local and state governments deserve a huge amount of blame for not having concrete evacuation procedures ready for the poor, but the federal response - FEMA's only serious duty - was outright embarrassing. And I know you don't want to fault the administration, but their vacation schedule while people were dying was outright embarrassing - Bush, flying over *two days* after New Orleans flooded, was among the first, with Cheney still vacationing in Wyoming, Andrew Card vacationing in Maine, and Condi spending the day shoe shopping at Ferragamo's and watching Spamalot.

The bomb wasn't just dropped - it was negligently tossed aside. As the city drowned and went to anarchy, no active duty military were sent in, and only a handful of poorly equipped national guard (the 256th's support brigade having most of their disaster recovery eq). FEMA toyed with the idea of getting school bus drivers to pick up people while squallor gathered at the superdome and thugs terrorized the convention center. Food and water weren't anywhere to be seen. Etc.

There's a lot of blame to go around. A damn lot. People have a right to be furious, at a lot of people - local, state, and federal. And I join them.

From the government publication http://pubs.usgs.gov/fs/fs2-00/

Melting of the current Greenland ice sheet would result in a sea-level rise of about 6.5 meters

That's about 21 feet, the effects of which you can guess by looking at the nice map included with this publication that outlines the affected areas of the South in red.

Can anyone think of a solution that would cover all of that coastline shown on the map? That's a lot of coastline. Better not to pick a fight with nature in the first place, I would say.

Without the barrier islands, New Orleans needs even bigger and stronger levees to stay above water. The existing system was intended to resist only a Cat 3 hurricane, and that was with the barrier islands in place to slow down the storm surge. With them gone, a relatively minor hurricane could swamp the city again. And minor hurricanes come through all the time. There might even be another one this year. So the city really can't be reoccupied until new, stronger, levees are in place.

There will be some rebuilding. The central business district and the tourist areas will probably be fully protected and rebuilt. There will be housing for oil industry and port workers, but probably not in the low-lying areas. But when rebuilding is over, the population of New Orleans will be much smaller than it is now.

A similar hurricane, in 1900, flattened Galveston, TX. A hurricane with 120 MPH winds killed 6000 people and levelled much of the town. The entire town, 500 city blocks, had to be jacked up several feet, and a huge seawall built. The jacking and filling job took eight years. Building the seawall took from 1900 to 1962. Sixty two years. And Galveston wasn't below sea level.

Ever after, Galveston was a smaller and less important city than it was before the 1900 hurricane.

The interface is described in This thread in the Navicache forums. Just pass it the relevant information in the query and you get back an XML file with the data. When it first came out, I had to write a script to parse and import it, but it looks like the current GPSBabel understands the layout of the file natively, if you have space to dump the entire batch into your GPS unit. I grabbed the entire set some time ago, and now just periodically fetch "caches added or updated since" the last time I updated.

As for the GNIS reference data (the USGS-published database of populated places, natural features, radio towers, etc.), they can be downloaded state-by-state from here. For those living or just visiting outside of the US, another US agency also publishes a somewhat less comprehensive but still useful set of location data for various features downloadable from here, and, finally, if you want to play with street map data in the US, the US Census Bureau publishes the "TIGER/Line" data - at least when the census bureau site is accessible...

All of those latter data sources are in the public domain, being publications of the US Government, so they are Legally Free. (Perhaps an odd contrast for a government frequently accused of being bought-and-paid-for by wealthy corporations to the detriment of its citizens - whereas most countries thought of as less at the beck and call of businesses seem to all charge a fortune for this kind of data...) I find them handy for generating my own maps.

>> The earth has been here for millions of years....

Actually the age of the earth is thought to be about 4.54 billion years. Unless, of course, you are from Kansas.

I live in the New Madrid fault. There hasn't been a major one here since th 1811 one that caused the Mississippi River to flow backwards. Yes, there was one this year, but it was only 3 and no one felt it. We know there's going to be another massive one, but it's not exactly anything we worry about, and have only made cursory preperations. My parents bolted the bookcases to the wall, and the State of Illinois earthquake hardened the bridges in Southern Illinois, but that's about it. (That nut job, Iben Browning, was actually good for something.) It probably won't happen anytime soon, and there's nothing you can do to prevent it anyway. My parents do have earthquake insurance though. (In your face California! :) )

Speaking as a Californian, I am happy my taxes are paying to help out the folks in Louisiana and Mississippi. And should disaster strike where I live -- which it will, given enough time -- they'll help me out as well, and we'll all end up better off.

Now, that said, I'd hope that the rebuilding effort takes this disaster into account and that whatever replaces the devastated areas will be built such that it comes closer to withstanding another big hurricane. (Obviously it's impossible to build a city that'll survive unscathed if the storm is big enough.)

The federal government spends billions on a lot of stupid things I feel are a total waste of my money. This isn't one of them.

Not to worry, this is what the transmitter looks like

I'd Google for more references, but I have a plane to catch...

Your faith in technology you don't even understand is not going to save us. People who have studied these things say we're in trouble if we continue to polute the planet as we are, and if some major, concerted effort is not made to move from oil and coal to fusion and hydrogen we're all seriously screwed. Fusion power is a technology with a roadmap that will be ready around the time the oil runs dry and until then we have other, efficient, non-poluting ways to make hydrogen. We have solar, wind, and methane hydrates. Hydrogen fuel cells we can move to today, we just need more platinum (or a new way of making fuel cells that doesn't need platinum, and unfortunately there are no indications of that happening anytime soon). We can get that platinum from space using technology we've had for over 30 years.

The National Map Viewer at USGS has the ability to overlay topo maps (and a whole bunch of other data) over aerial imagery.

I'm afraid that Microsoft didn't "delete" Apple, they just used data that's older than they are. My understanding is that Microsoft is using the USGS Topographical data, which tends to get updated whenever the USGS feels like it. Google, OTOH, uses proprietary data which is only a couple of years out of date (as opposed to decades).

Nice conspiracy theory guys, but I'm afraid that the Register is just having fun getting you all worked up. :-)

That's not the case here. The great earthquake of 2004 ripped apart the crust of the Earth for approximately 150 km. The fact of the matter is that if all of that energy were concentrated at one point, and released simultaneously, it would have left a crater (the energy of the quake was larger than if all of the world's nuclear weapons were detonated).

It is also unreasonable to believe that 150 km of crust would be rigid in the sense that all points snapped simultaenously. In reality what occured is that it cascaded. One part of the crust slipped which provided the energy for the adjacent layer to slip. From physics we know that the rate of energy propagation due to shear stress is the speed of sound in that material (related to the bulk modulus for the material--which is why craters always form as hemispheres, but that is another story). So the fault kept of slipping at a very fast speed (but not instantly), over an enormous distance which is part of the reason why the sound file is so lengthy. One geophysicist remarked in another article (I think it was on MSNBC) that he could hear the crust being ripped apart. The frightening thing is that this was true.

The USGS National Map has had the ability to overlay map symbology on aerial imagery for years. For example, check out this map. Furthermore, Google's imagery of urban areas is often the same aerial photos used by the USGS and Terra Server. Of course, Google Maps is way cooler to use than either the USGS or Terra Server.

It's interesting to see places where the satellite images and map date do not line up quite right. In my neighborhood, they are just off, the map data is slightly right of the images. You can see it here."

So is the map data wrong, or did my my whole neighborhood shift slightly to the left? It is California, we do have the occasional 'ground shiftage'.

And someone would confirm this for me, their contact email address for this project bounces back. So much for the feedback line.

Here is what I sent:

USGS has a list of named features surrounding the Apollo landing sites
available here:

http://planetarynames.wr.usgs.gov/moon/moonland.ht ml

Assuming that NASA or someone has more detailed imagery of at least this
area (given it's significance), is there any chance of having these
points listed as well. You can always leave the rest of the moon at it's
current dairy detail :)

Thanks, neat idea btw.

I wish they would have taken this more seriously. The moon actually have a massive number of named points of interest which would be nice to be able to look up.

Personally, I name all of my software projects after features named during the Apollo landing missions. For a second there, I thought I might be able to provide a url in the javadocs to a map of the actual landmark for the team. While not very useful, it certainly would have been educational.

Google Maps is not purposely limited, they are simply using the highest-resolution data available to them (for free?) from the USGS. Try downloading the highest resolution you can from the USGS, it is identical to the Google data (same time it was taken, etc.).

Try it for yourself at: http://seamless.usgs.gov/!
(Posting AC because I don't have an account. Not a troll.)

About coal being worse than nuclear, I have not the best references, but here are a few:

http://geology.cr.usgs.gov/energy/factshts/163-97/ FS-163-97.html
http://www.ornl.gov/info/ornlreview/rev26-34/text/ colmain.html
http://yarchive.net/nuke/coal_radiation.html

Nadaou talked about SRTM datas. Their resolution outside USA is 90 meters which is maybe not enough for you. You can try to get ASTER data (Digital Elevation Model of 30 meters resolution) to complete SRTM locally, however with less quality (there are no post-treatments on them), and a very very reduce coverage ...

Currently the coverage is of only seven DEM on Ghana.
But maybe it's the geographical position you are looking for ...

An article from John Childs presenting quickly ASTER format
John Childs also explains how to obtain data from the "EOS Data Gateway"
Homepage of ASTER

--

Cedric

The biggest fish that I've caught in my life weighed 30 lbs., and it seemed like a monster. I don't think I want to catch a fish that weighs more than I do.

While not as "cool looking" as a Google Map, the USGS has a very nice recent earthquake map that is clickable, down to coordinates & fault name.

http://quake.usgs.gov/recenteqs/latest.htm

That's the raw data files, buddy.

Yes, and they are for sale too.

Good thing everyone ignored your mod advice.

You mean like this:
http://nmviewogc.cr.usgs.gov/viewer.htm

or maybe this:
http://nationalatlas.gov/

Or is that not enough?
I know they're not overly professional, but it's still not bad for something free to the public available through an internet browser.

While those are some great and informative links, they are useless for actual geologic applications. The grandparent poster isn't talking about the pretty aerial photograph (orthoimagery) you see available in programs such as World Wind and the National Map Viewer. Those simply have high resolution aerial photography for a small number of urban areas in the United States.

The grandparent post is specifically talking about extraordinarily high resolution aerial photography sets that can be put together to exam under a stereoscope, which basically allows you to exam a high resolution photograph in 3D, giving the picture depth/relief.

This is useful in various studies, such as mapping past/potential landslide areas, mapping active/inactive fault traces, and determining relative elevations of various topographic features to see if they are related (just a topographic map will not help for this, since you want to see if rock type, erosional properties, vegetation, etc are the same between multiple features if you want to correlate them). There's a multitude of reasons for this information. It serves a great purpose when time/financial constraints make it inconvienent to go out into the field, or even doing preliminary work BEFORE you go out into the field, so you know what the area is like.

These aren't available online or for free, and the USGS has extensive high resolution aerial photography for most of the United States. But you have to order it, which can be quite expensive (especially if you are a student/academic doing a research project) and the fact that your taxpayer money has already payed for this to put it into the public domain.

You mean like this:
http://nmviewogc.cr.usgs.gov/viewer.htm

or maybe this:
http://nationalatlas.gov/

Or is that not enough?
I know they're not overly professional, but it's still not bad for something free to the public available through an internet browser.

While those are some great and informative links, they are useless for actual geologic applications. The grandparent poster isn't talking about the pretty aerial photograph (orthoimagery) you see available in programs such as World Wind and the National Map Viewer. Those simply have high resolution aerial photography for a small number of urban areas in the United States.

The grandparent post is specifically talking about extraordinarily high resolution aerial photography sets that can be put together to exam under a stereoscope, which basically allows you to exam a high resolution photograph in 3D, giving the picture depth/relief.

This is useful in various studies, such as mapping past/potential landslide areas, mapping active/inactive fault traces, and determining relative elevations of various topographic features to see if they are related (just a topographic map will not help for this, since you want to see if rock type, erosional properties, vegetation, etc are the same between multiple features if you want to correlate them). There's a multitude of reasons for this information. It serves a great purpose when time/financial constraints make it inconvienent to go out into the field, or even doing preliminary work BEFORE you go out into the field, so you know what the area is like.

These aren't available online or for free, and the USGS has extensive high resolution aerial photography for most of the United States. But you have to order it, which can be quite expensive (especially if you are a student/academic doing a research project) and the fact that your taxpayer money has already payed for this to put it into the public domain.

You mean like this:
http://nmviewogc.cr.usgs.gov/viewer.htm

or maybe this:
http://nationalatlas.gov/

Or is that not enough?
I know they're not overly professional, but it's still not bad for something free to the public available through an internet browser.

While those are some great and informative links, they are useless for actual geologic applications. The grandparent poster isn't talking about the pretty aerial photograph (orthoimagery) you see available in programs such as World Wind and the National Map Viewer. Those simply have high resolution aerial photography for a small number of urban areas in the United States.

The grandparent post is specifically talking about extraordinarily high resolution aerial photography sets that can be put together to exam under a stereoscope, which basically allows you to exam a high resolution photograph in 3D, giving the picture depth/relief.

This is useful in various studies, such as mapping past/potential landslide areas, mapping active/inactive fault traces, and determining relative elevations of various topographic features to see if they are related (just a topographic map will not help for this, since you want to see if rock type, erosional properties, vegetation, etc are the same between multiple features if you want to correlate them). There's a multitude of reasons for this information. It serves a great purpose when time/financial constraints make it inconvienent to go out into the field, or even doing preliminary work BEFORE you go out into the field, so you know what the area is like.

These aren't available online or for free, and the USGS has extensive high resolution aerial photography for most of the United States. But you have to order it, which can be quite expensive (especially if you are a student/academic doing a research project) and the fact that your taxpayer money has already payed for this to put it into the public domain.

You are egregiously wrong and should be modded down accordingly.

Here is free USGS topographic data from the USGS:
http://edcdaac.usgs.gov/gtopo30/gtopo30.asp

That's the raw data files, buddy. Can't really ask for much more than that can ya. BTW, if you check out the NASA worldwind project you will find that there is an incredible amount of freely availble GIS data being served up on wms servers all over the world.

http://nmviewogc.cr.usgs.gov/viewer.htm

You mean like this:
http://nmviewogc.cr.usgs.gov/viewer.htm

or maybe this:
http://nationalatlas.gov/

Or is that not enough?
I know they're not overly professional, but it's still not bad for something free to the public available through an internet browser.