Landscape Change - How Fast?

A major question from the beginning of geology as a science has been how fast does change take place? From the Literalist read of the Bible, it would seem 6,000 years is far too short a time to permit the development of tens of thousands of meters of sediment, with remains of primitive life-forms at the bottom and advanced life-forms preserved at the top. The first rough estimates of the rate of sedimentation were made in England, by thoughtful natural scientists measuring how fast mud accumulated in a pond. These early geologists had already mapped thick stacks – thousands of meters of distinctive layers - of sediment in cliffs, road-cuts, and quarries. They had seen the same sequences long distances away, implying the same sedimentary process was happening over a very wide area. Finally, they had realized that for mud and sand to accumulate to thousands of meters of thickness, would take at minimum many millions of years. This was really the first baby step of geoscience.

Q: Hello, my name is Jurgen and I am currently enrolled in an AP Environmental Science class and have a question about river formation. I hope you can answer my question.

How long does it take for a gully or rill to be formed into a river if there is a constant stream or supply of water running through the land?  Thank you.

--Jurgen P

A: Time for a gully to become a river can vary wildly from less than a hundred to many millions of years. Generally, most terrains are in some sort of equilibrium and don't change much over time – unless disturbed by something, like a tectonic event. This is sometimes called "punctuated equilibrium." The change of a feature from one form to another (like a gully to a river) implies a permanent shift in the rainfall regime - some form of climate change – or tectonic uplift.

Change from a gully to a river could also have a lot to do with human intervention. I've walked down 10-meter-deep, steep-walled gullies that were really mini-canyons (Arroyos) in SE Arizona. These apparently didn't begin to form until man introduced cattle in the late 19th Century. Early journals from some of the first visitors describe “grass that was belly-high to a horse.” These cattle quickly wiped out the native prairie grasses by over-grazing the landscape. When Arizona earned its statehood in 1912, it had a human population of about 12,000 people, but an estimated cattle population of perhaps 10,000,000. Soils started disappearing rapidly with no roots to hold them, and small rivulets began to rip through the landscape and form small canyons in less than a century. Events like this, and the 1930's Dust Bowl, lead to the formation of the US Bureau of Land Management and the US Soil Conservation Service during the 20th Century.

Tectonic uplift can also weigh in powerfully, but tectonic shifts are generally relatively slow - slow at least in typical human time-frames. The Grand Canyon only began to form (cut down through pre-existing Precambrian to Mesozoic rocks) about 70 million years ago. The actual timing of the initial incision and the final down-cutting is still being argued today by geologists as more evidence accumulates, but it appears to have been quite rapid at the beginning.

Unconformity? Disconformity?

Here's a purely geologic question by someone who has already taken at least one course in geology. The question opens up and highlignts the three-dimensional aspect of geology - and why mathematics (especially geometry) is such a fundamental prerequisite for studying geology. Some people persist in saying that a geologist is just someone who didn't do well in physics or math. The hard reality is that physics, math, chemistry, and English composition are the building blocks - the basic tools - of a modern geologist. Some of the most sophisticated geology being carried out these days is done with computers. Drill-hole information is fundamentally three-dimensional, and the ability to construct three dimensional landscapes from surface mapping and drill-hole intercepts is just so very cool. To rotate this 3D landscape on one or several computer screens, showing how individual components evolved in time in a single giant cubic space... is absolutely essential to numerically assessing any resources the land under the geologic map may host.

Q: I have a question regarding identifying unconformity on geological map. I have attached a map as an example. How do we identify unconformity on such 2D geological maps if each colour represents a different rock? Please advice.

Thank you and hope to hear from you soon. Regards

- Hazel A

A: I have not downloaded your map and looked at it in detail, but just looked at it via the attached thumbnail. We are discouraged pretty strongly from downloading and opening any files from unknown individuals that might potentially be vectors for malware. For the purposes of this Q/A, a map is not really necessary, however. 

I'd like, instead, to address your question on a somewhat broader level: The inherent problem with a geological map is that it represents the surface of the land. It's a view looking downwards from space, which is not always the same as looking downwards in time. Sometimes, with tectonic and erosional events, older in time doesn't necessarily mean deeper in the Earth.

An unconformity is a gap in sedimentary deposition for one of several fairly specific reasons: non-deposition, subsequent erosion, etc. It is not easily represented in a geologic map, which only shows just one sub-horizontal surface - the part exposed to the sky. An unconformity means that there has been a time break in the geologic record. This is quite different from a juxtaposition of different geologic units due to, say, a thrust fault (though they could both be involved at the same time). 

In practicality, this means that the geologist who produces the map must somehow indicate or convey any unconformity (or disconformity, or nonconformity, or paraconformity, etc.: see http://en.wikipedia.org/wiki/Unconformity ) in her/his *Correlation of Map Units* columns on the side of the geologic map.

For most people not intimately familiar with a particular local or regional geology, it would be very difficult if not impossible to determine if some break between units is an unconformity or a fault juxtaposition just from looking at a geologic map alone. A change in rock-type could mean any of several much more common things: a change in sedimentary regime (like an ocean transgression), an intrusive event (like a big granite body punching up from the Mantle), a volcanic eruption, any of several different kinds of fault, etc., exposed at the earth's surface. 

It comes down to the fundamental difference between a map view (looking down at the ground from space),  and a cross-section view (looking at the ground side-ways, as if a giant trench had been cut in the landscape). However, even in an exposed cross-section, considerable sleuthing is required to determine if a break is an unconformity or not.

Volcano Questions from the 5th Grade

Some questions are just fun to get. Perhaps it’s the teacher in me that likes to see young eyes light up with intellectual excitement. I infer from the following that volcanoes first get talked about seriously in the 5th Grade. It's beyond the soda, vinegar, and food coloring lesson.

Q: Question for my 5th grade class!

My students have some questions,

-           Megan A

1. Why do volcanoes erupt?

A: Pressure builds up from rising low-density magma below the earth. The low density is caused by the heat from the Mantle and Core of the Earth convecting upwards, sorta like a pot of Cream of Wheat cooking, or a lava lamp. The path of least resistance is to break out through the Earth's Crust at its weakest point. Where are those weakest points? Well, where you now see volcanoes is a pretty good hint. Some geologists have speculated that when tectonic events leave faults, and two faults happen to cross, that may make the intersection a “target of opportunity” for rising magma. However, there are a number of other factors involved, including where is the magma rising, and from what source, is there some under-plating of the crust happening, are there some gross compositional differences in the crust, etc. 

2. What are volcanoes like?

Some volcanoes look like cones (Mount Hood in Oregon, Mount Fuji in Japan). Some look like giant bulges (Mauna Loa in Hawai'i). Some volcanoes don't look like much of anything. You just see black-gray lava that has broken out of fissures, then poured out and run across the land in all directions – but generally the "pouring" goes downhill. There are vast, nearly impassable volcanic fields in western Saudi Arabia. There are huge obsidian flows (volcanic glass, caused by lava emerging in water and cooling too rapidly to form mineral grains) at Medicine Lake volcano in California. These look like a giant painted the ground with swirling green-black glass.

3. What is lava like?

Lava is very hot initially when it first reaches the air - it glows yellow-red from incandescence in cracks and at the flow-fronts. You can walk on it, because it is denser than a human body, but it is pretty rough on your boots. It melts boot-soles while hot, and cuts them up when cold because lava (e.g., in Hawai'i) is really just black glass. As lava cools, it sounds like a bowl of Rice Crispies crackling. As the flow-front reaches trees and houses, it engulfs them and the very high heat sets them on fire. This often forms tree molds - molds of where trees once were before being engulfed by the lava, for instance in HAwai'i and at Newberry Volcano in central Oregon. On Mauna Loa, a fast moving flow-front in the 1950's burst out of a fissure high on the volcano's west flank. I talked with a man who watched the flow run down the volcano's flank and onto a forest. It clipped off the trees at the base, then stack them vertically like bunched toothpicks at the front of the flow as the whole thing raced downhill at 60 kilometers per hour into the Pacific Ocean. 

4. Have you seen a volcano erupt?

I was inside Mutnovskiy volcano in Kamchatka when it started venting. I watched Mount St Helens erupt several times in 2004-2005. I've walked over active (evolving, moving) lava fields from Kilauea volcano, tracking the growing flow-front using a GPS device.

5. Is your job dangerous?

Not any more dangerous than driving a car on a Friday night when there are drunks on the road. Most volcanologists know someone, a friend or a colleague, who has died while working on a volcano, so yes, volcanoes ARE dangerous, and must be treated with respect. Because volcanoes are so dangerous, we take extra precautions when working on one that is restive, and generally stay well away of they are erupting. It's sort of like wearing seatbelts when you drive in a car. If you don't you are being deliberately careless - and statistically you have a much higher chance of dying. 

How Can You Have NEGATIVE Earthquake Magnitudes?

Some questions require an explanation of a different kind of number that some students haven't yet seen before. These different ways of expressing numbers were developed to help explain very large things, very many things, very small things, or very complex things, among others.

Q: Hi, My name is Anthony. I was wondering how negative magnitudes can be recorded for earthquakes, and what is the smallest earthquake ever measured? Thanks
- Anthony N

A: Earthquake magnitudes are actually exponentials, so a negative exponential doesn't mean a "negative" value in the usual sense of the word. I'm hoping you've already had exponentials in school - or at least you can go ask a teacher what they are.

For instance,
10(exp)+2 = 10^+2 = 100.0
   The exponent here is +2 and it means one hundred. This is 10 to the second power.
10(exp)+1 = 10^+1 =   10.0
   The exponent here is +1 and it gives ten - ten to the first power.
10(exp) 0  =  10^0   =     1.0
   The exponent here is 0 and it means one - ten to the zeroth power.
10(exp)-1  =  10^-1  =     0.1
   The exponent here is a negative number, but it refers just to a SMALLER value than a non-negative exponent would. Here ten to the minus first power means one tenth.

The smallest earthquake ever recorded is a bit more difficult to answer. There are three parts to the answer:

1. It depends on the sensitivity of the instrument, and how close the hypocenter of the earthquake (the actual rupture point) is to the instrument. There are a lot of sensitive seismometers set up around the world as part of the global seismic network - they are designed to look for earthquakes in the magnitude 2 range or higher. There are also some really, really sensitive seismometers positioned on and around volcanoes. These are set up to look for earthquakes so tiny that earthquake people wouldn't really be interested in them - events so small that only one or two of the nearby instruments may even detect them, and no human would likely feel them.

2. I believe that the smallest recorded events are probably in the M= -2 range (negative two magnitude) for a very clean, noise-free station. That's also what two seismologists in my office tell me (independently!).

3. When you are looking at magnitudes this small, you are also dealing with a lot of noise: cars driving by on a nearby highway, people or animals walking nearby, wind vibrating trees and buildings, etc. In a sense, the smallest earthquake ever recorded is sort of meaningless, because it becomes harder and harder to even know if it's real - or just noise. Also, the smaller the seismic events, the more common they are. As an example, the US Geological Survey estimates that there were about 1,300,000 earthquakes worldwide in the 2.0 - 2.9 magnitude range. There are MANY more as you get to ever smaller magnitudes. See an earlier chapter on how many earthquakes are detected each year in each magnitude range (http://askageologist.blogspot.com/2012/11/earthquakes-how-often.html).

No one is really interested in most of the wiggles you see in these two examples:

http://www.avo.alaska.edu/webicorders/Veniaminof/  
This is an instrument set up on Veniaminof volcano in the Aleutians. At 8:30am PDT on 22 October, I can see a few distant teleseismic events (distant earthquakes) and a lot of tiny events that may or may not be small volcanic earthquakes, or in some cases just small rock-falls from the crater walls. I can also see some large swings of the recorder that are instrument noise - probably electrical noise, either human-caused or natural, like distant lightning.

Whereas, if you look at Augustine volcano's webicorder for that same day, you see only a huge amount of wind noise:

http://www.avo.alaska.edu/webicorders/Augustine/
This is an instrument set up on Augustine volcano in Cook Inlet in Alaska. At 8:30am PDT on 22 October I could only see masses of blue "ink" on the plot that indicate a lot of wind noise on this station. There is so much noise on this seismometer record at this point in time that any "real" earthquake would be impossible to see.

~~~~~

How Many Volcanoes Are There In The World?

How many of X are there in the world? This is a common question that often provides a surprising answer. You might be surprised at how many drill rigs exist or once existed in the Gulf of Mexico, for instance (over 4,200!).

Q: how many volcanoes are there in the world?

- Josh S

A: The Global Volcanism Program of the Smithsonian Institution lists 1559 volcanoes with eruptions happening during the Holocene period (the last 10,000 years). This means they are listing active or potentially active volcanoes. There are MANY more volcanoes in the world than that, of course. Some of them are just older and long inactive, like parts of Craters of the Moon national monument in Idaho (however some features there are as recent as 2,000 years ago), or volcanoes that erupted in Venezuela over a billion years ago. Some volcanic features that are not on the Smithsonian volcano database are just too small to easily list. While serving as the chief scientist for volcano hazards in the US Geological Survey, I assigned one of my senior scientists to do a full assessment and summary of the Cascades volcanoes of Washington, Oregon, and California. I thought there might be 15 volcanoes there. He ended up with a list of over 3,500 - because he counted every focal point of volcanic activity including small scoria cones and maars. 

Is the Big One Coming?

The following query arrived just a day before the M=6.0 Napa, California earthquake of 24 August 2014. Unfortunately, I could not respond to the obviously nervous individual until after that event took place. The bottom line is that non-human risks change little over time – they are just there, but they can be dealt with. However, people tend to obsess over what scientists call “high-impact-low-probability” events – like a shark attack or an earthquake along the so-called Pacific Ring of Fire.

Q: Hello I live in California and currently I'm getting very scared with all the current activity around the ring of fire. My question is whether this is normal activity or warning signs for bigger earthquakes to come, or even the "big one"?

-          Dolores L

A: The activity you are noticing is normal - it has been going on for millions of years. Sometimes it seems more exciting in some locations than normal, but this is still normal.

When you write of a "big one", this is also normal: we are expecting a subduction mega-quake in the Pacific Northwest anytime in the next one day to 300 years. Some older schools are being earthquake-retrofitted in Oregon as I write this. The Earth's crust is an active place, and the truth of the matter is that no matter where you live there is some degree of local (potential) hazard everywhere, whether hurricanes, volcanoes, domestic violence, earthquakes, drought, floods, car-accidents, or tornadoes.

The rational way to deal with these is to evaluate each hazard carefully – and there are public agencies like the USGS that do this all the time, very conscientiously. Once you know what the risks are – and most of the "big ones" are high-impact-low-probability – then you can plan accordingly. I bought my home on a slope for the view, but I checked the foundations carefully before I paid for it. I also paid an extra 15% earthquake premium on my homeowners insurance.

To put things in perspective: people react strongly to learning that a swimmer was killed by a shark, but 10's of thousands of sharks die brutally at the hands of humans each year rather than the other way around. Compare the 1 - 3 human shark-bite deaths to over 35,000 highway deaths in the United States last year. While seat belts, speed limits, and no-texting are theoretically enforced, no one seems to get particularly excited about this huge killer.

Another perspective: My father, before he died of lung-cancer, lived in a high-rise apartment in San Francisco less than 10 miles from the San Andreas Fault. I once asked him if he worried about it much? His response opened my eyes. “Listen,” he said, “I could enjoy the view of the Bay from here, or I could hunker down in a basement somewhere and worry constantly. Long ago I chose the former.”

Bottom line: the world is NOT about to end. Study your own personal risks, and then take rational precautions to mitigate them as much as possible without going overboard. Just taking any steps will lessen your worries, because you will be actively doing something about them. This could include putting up a supply of drinking water and food to last you during a local or regional disaster. Or better yet, a years supply so you can also help your neighbors. 

RUBIES!

The US Geological Survey does not employ gemologists – while there have been several within our ranks historically, they have been amateur gemologists who have pursued their interest on their own time. Nevertheless, gems DO come from the ground, and could reasonably be construed to be an ultimate product of geology. The following question is typical of the kind we receive about gems.

Q:           Is there somewhere in California near Modesto that I can have a rock collection looked at? We are almost positive that we may have found some raw rubies! They have passed the scratch test and are very heavy and hexagonal shaped. 209-xxx-xxxx

- James

A:            We can't do gemology for you - the US Geological Survey is tightly constrained to work on only particular national objectives that Congress sets, including mineral resource assessments, volcano hazards, etc. 

My recommendation to you is that you contact a local gemological society and ask for guidance. I would NOT recommend going to any jewelry store, as they only focus and specialize on the end products. 

You might try:

http://www.americangemsociety.org/ ... but keep in mind that this is a trade association of retail jewelers, independent appraisers, suppliers, and selective industry members, and only incidentally will they have any component that might be of help to you. 

           You would probably do better with:

http://www.gemsociety.org/ 

...or even better with a local society of educated amateurs, like the San Diego Mineral and Gem Society:

http://www.gemsociety.org/

Finally, please keep in mind that there are beryls and other igneous minerals like garnet and eudialyte that can easily be mistaken for rubies by inexperienced people. A true ruby is a pink to blood-red (so-called “pigeon blood”) colored gemstone, a form of the mineral corundum (aluminum oxide). Ruby has a hardness of 9 on the Mohs scale, and is considered one of the four precious stones, along with sapphire, emerald, and diamonds. The red color in a ruby is caused mainly by the presence of the element chromium in the crystal lattice.

~~~~~

The Dust Bowl, King Solomon, and Country Western Music

Sometimes – even after all these years – I am amazed to learn of yet another series of cultural connections all tied together by geology. The following Q&A is just one of many examples of this. Another example is how modern Venezuelan politics and its history are underlain both literally and figuratively by its ancient Archaean geology. This Venezuelan example would take too long to share here, but it can be found in a book my wife and I have written titled “2 Worlds, The Real Venezuela: Living on the Edge of the Jungle and the Rise of Hugo Chavez” (http://www.barnesandnoble.com/w/2-worlds-the-real-venezuela-jeff-wynn/1112567534?ean=9780615428444). By the way, the girl holding the monkey in the cover photo is our youngest daughter.

Q: I just watched a show on the history channel. Part of the show covered the "Dirty 30's" and how the "Dust Bowl" helped shape human kind today. My question is, of the possible millions of tons of top soil blown away. Where did it go? Did the eastern sea board states get a foot taller during those years or what? Thank you for taking the time to answer my question.  Sincerely,
- Bart A

A: The Dust Bowl was caused by improper farming practices that destroyed the native prairie vegetation and their root systems - and didn't replace them. The US Soil Conservation Service (Now the Natural Resources Conservation Service, or NRCS) was created to first understand, then mitigate the consequences of plowing fields in prairies. In 1933, its original incarnation the Soil Erosion Service was created within the Department of the Interior, with Hugh Bennett as chief. Bennett was a visionary soil expert who had been publishing scientific papers on the subject since the beginning of the 20th Century. He practically invented soil science.

       To answer your specific question, yes: the soil goes elsewhere, and other places grow “taller”, though you might not be able to easily recognize this. Winds tend to scour certain localized areas, and then distribute the soil and dust outside these areas - but much more widely. Thus it may not seem like parts of the rest of the country developed deeper soils, but they did - though very marginally. The airborne distribution process drops out the heavier particles at shorter distances, while the finest dust can theoretically blow around the world. You might speculate where some of the dust that always seems to find its way into your house originally came from.

Two anecdotes may help you understand this better.
1. Satellites can see dust from the western Sahara blow thousands of kilometers out into the central Atlantic Ocean. Ultimately it collects in the abyssal ocean depths, where coring has actually measured it and its growth rate. It may even have a part in the Atlantic Hurricane development process.

2. While I was working in central Saudi Arabia two decades ago, I was asked to provide geophysical assistance to a geologist trying to evaluate a small ancient mine (SAM) named an-Najadi. This mine was one of at least 852 small artisanal gold mines found in Saudi Arabia today, and apparently formed the major source of gold reported in King Solomon's treasury.

     While visiting the site I saw that the geologist had used a backhoe to dig trenches. His objective was to get down through the soil to the bedrock, to figure out what the bedrock structure was - so he would know which direction to point or orient his evaluation drilling program. At the bottom of one trench I saw two round stones - they turned out to be grindstones used by the ancient miners to crush the quartz grains holding the tiny fragments of gold that the miners were after. I am looking at those two stones in my office as I write this.

     On the sides of the trench I saw three white lines, and asked the geologist about them. They turned out to be slaked-lime floors of ancient dwellings. I could see the oldest one, then one a meter higher stratigraphically above it - that therefore had to be at least a thousand years younger - and then one above that. The trench was 14 feet (4+ meters) deep. The lowest level was occupied by miners in Solomon's time - 3,500 years ago. The 14 feet of soil above the lowest dwelling level arrived since that time and is called "loess", a German word for blown-in soil. Most of this soil had been blown in from the west. It had come from the eastern Sahara, and crossed the Red Sea to get there. I have personally experienced sand storms in that area that kept aircraft from landing - because pilots could not see the ground for up to three days at a time. Operation Desert Storm in 1990-91 was rushed forward in time to beat these seasonal wind storms called the Shamal. These storms happen during the period of monsoon storms that lash the Arabian Sea for several months in the Spring every year.

     This all tells us that over-grazing in the proto-Sahara, starting thousands of years ago, had already stripped most of North Africa of its protective vegetation, leading to the ever-expanding "desertification" process we see that continues today... and which Oklahoma experienced for a short period in the 1930's.

     Soil conservation is an important lesson we learned from the Dust Bowl of the 1930's. Some of the Oklahoma economic refugees migrated to California, and a country western band leader named Cousin Herb Henson brought his musical tradition from there - and lived across the street from me when I was a child in Bakersfield, California. I still remember Bakersfield being one of two major Country Western music centers in the country after Memphis... and I can still remember the disparaging name of "Okies" being used for these poor migrants decades after they arrived.

     I hope this answers your question, and perhaps puts it in a wider context.

Jeff Wynn's Special Crash Diets

I plan to patent these things. Consider this the Public Notice in the Federal Register - I have 12 months to initiate contact with the US Patent and Trademark Office. These Jeff Wynn's Special Crash Diets (patents pending) will be useful for anyone desiring to lose 5-24 pounds VERY quickly. That summer bikini bod? Just 7 - 10 days away, thanks to Dr. Wynn. The oldest of the three Drs. Wynn.

You will not find these diets in O magazine. Oprah Winfrey is a sissy and won't try them.

1. The Duodenal Ulcer Diet - good for 24 lbs in 3 weeks. You will need to chew aspirin without water when feeling a lot of pain for this one. If you have a German grandmother, she will teach you how to do this. The taste is bitter, but it can become an acquired taste that is not unpleasant if you work at it. The consequences manifest as a feeling of light-headedness, a rapid loss of your tan, and soon you will also notice black, tarry stools. Don't let this go on too long, however, or you will literally bleed out. Stay hydrated with Kool-Aid or you will face congestive heart failure.
Ancillary: You won't feel like eating at all, but you should probably force yourself to start on soft stuff (like white bread and bananas) and stop eating the aspirin after 10 days.

2. The Shigella Diet - good for 14 lbs in 10 days. You may have to travel to the deep southern Venezuelan jungle for this one. It requires a cook who never washes his hands, or anything else, and who butchers chickens - and leaves the offal - on the edge of your jungle encampment. They do this because everyone is fearful of El Tigre, also known as a Jaguar, and of course no self respecting Jaguar would THINK to follow its nose to the scent of rotten chicken guts and thus into your hammock. I WILL note that in three years in the deep jungle I MAY have seen just one pug mark from a small cat, but the psychological fear runs rampant among Venezuelans. Everyone carries a machete with them, even to venture 10 meters into the forest to relieve themselves. The microbe donated by the filthy cook first manifests as light-headedness with a ringing in the ears. It probably also involves a high fever, but you won't likely have a thermometer with you to prove it. Within a day it turns to nausea and diarrhea, and within a day after that the diarrhea begins to show significant blood. LOTS of blood. Most people living in southern Venezuela are immune to this microbe, or else they are dead (Natural Selection - Darwin was right). Delicious additional details can be found at http://www.barnesandnoble.com/s/Jeff-Wynn?store=ebook&keyword=Jeff+Wynn
Believe me, you WILL run out of available un-besmirched jungle, and be sure to have at least 10 extra batteries for your flashlight. You never know what you will step in otherwise.
Ancillary: You can stop the weight-loss at your leisure by drinking an entire bottle of Kaopectate with Neomycin. You don't want to fritter around with any teaspoons here.

3. The Ruptured Colon Diet - good for about 10 lbs in 7 days. This one requires taking some very hard falls to initiate. You must try to strangle at least 10 people up against a wall. They will then hold on to your shirt, ears, or chest hair, lift their legs, and drop straight down. If you are not quick with your hands, your face will then hit the wall VERY hard (that's the intent, anyway). Next, the "victim" will cup hands behind your heel and shove a shoulder hard against your knee, forcing you to fall backwards in what is technically called an Ura Nage or simply just a "Tree Fall". You can't roll out of this one because your leg is locked out. This little exercise works better if you are older, as diverticula increase with age (40% at 40 years, 60% at 60 years, etc.).
Ancillary: The doctors don't want to carve on you, despite what you may hear about fees-for-service (I suspect they don't like the smell), so they will put you on a Dextrose-and-Morphine diet. I didn't name it this, because the diet also requires taking a highly toxic antibiotic, such as Flagyl. In fact, the Flagyl itself will probably do the job, because (a) the doctors INSIST that you take a cycle of antibiotic to the Bitter End, and (b) the metallic taste in your mouth makes any food taste like a carburetor.

4. The Extracted Tooth/Teeth Diet - good for 7 lbs in 7 days. You simply need to have a tooth extracted for this one. Two teeth, if the dentist accidentally fractures a neighboring one, will serve even better. Ignore the instructions to avoid spitting and eating any solid foods after two days and the clots will come out, exposing your jaw or your skull in what is euphemistically called a "dry socket". It's not at all dry, because food and saliva quickly pack the openings and the pain rapidly ramps up to a 5 - 6 level. However, this provides an excellent incentive to stop doing anything with your mouth, including talking, eating, etc.
Ancillary: The sockets will heal (close) in about a month. You can temper this diet with liquid protein drinks, but you will need to eat a sheet of newspaper a day to provide adequate fiber. Legal liability issues prevent me from explaining what happens otherwise.

5. The Vitamin "O" Diet - good for about 5 pounds in 7 days. I can't take credit for the name - my kids came up with that. To do this right you will need to work in an environment - say a ship - where you are nauseous from 5-meter seas for several days. It works best if your work window is always at night when everyone else wants to sleep (there are some people who actually insist on sleeping at night). You can keep your brain fueled by eating a three-column sack of Oreos every 12 hours. Don't worry, your system throws it off quickly, and any sugar that doesn't just run straight through you will keep EVERYTHING humming. This particular diet involves virtually no pain, by the way.
Ancillary: This one is easy to turn on or off. The boat driver can simply turn into the wind, which will reduce the pitch, roll, and yaw to just cyclic forward-back pitches. You can also go to bed and kiss off about half of your data.

Several other possibilities come to mind, but they generally require surgery. I will keep them to myself until time for Public Notice in the Federal Register. You're welcome.

~~~~~

Hot Magnetic Oxygen Water World

There is another version of the Anthropic Principle, one that applies only to the planet Earth. We may be more alone, or unique, in this universe than the Drake Equation - the calculation of the possibility of other life out there in the universe - may have led us to believe.

The deepest hole ever drilled into the Earth's crust reached down to about 7.6 miles (12 km) below the Kola peninsula of northern Russia. The technology available to humankind cannot get below that depth (and that depth took 24 years of drilling and billions of Rubles to achieve). The rocks are so hot and plastic with overlying rock pressure at those depths that the hole closes in on the drill bit - and partially fills the shaft back in from the sides as the bit is drawn back to the surface to be replaced. So... the maximum depth achieved by humanity's best effort is less than 1/10,000 the Earth's diameter, or the distance of a short commute on a Monday morning. We actually know more about galaxies, comets, and the moons of Jupiter and Saturn than we do about what lies below our feet on our own planet. No matter how you look at it, we cannot really touch virtually all of the world beneath our feet.

In other words, everything we think we know about the interior of the Earth is obtained by very indirect means, and a lot of this is from mathematical modeling.

To see below the depth of the Kola well, we must rely in electrical geophysical methods like magnetotellurics (which is one of the things that I "do" as a geophysicist; it can detect resistivity layering down to perhaps 50 km or so), and on earthquake seismology. For nearly a century seismologists have traced the powerful vibration signals from very large earthquakes as these signals propagate and refract through the Earth. By comparing the time of arrivals elsewhere around the planet - and whether just P-waves, or P-waves and S-waves together make it - they can discern contrasts in density and other physical parameters as these change with depth. P-waves (or primary waves) are pulses of energy, momentarily compressing the material they pass through. It's the blast wave from an explosion expanding outward. S-waves (or secondary waves) are shear waves, oscillating material back and forth, sideways, as they pass through the material. Think of how you would move your hands forward and backward to tear a piece of paper. A key feature of S-waves is that they cannot propagate through a liquid. Think of trying to use your hands to tear water. By the 1920's seismologists had used the initial earthquake seismic information and some density calculations to conclude that there is a solid iron core to the Earth, surrounded by an outer liquid iron part of the core. The outer liquid core is overlain by a hot and plastic Mantle, and finally by a relatively thin crust serving as a very thin solid shell above them both. All living things live on or just beneath the top of that crust.

The methodical genius who first figured all this out was a quiet Danish lady named Inge Lehmann, who died in 1993 at 104 years of age.

Seismology and magnetotellurics show us the layering in the Earth with depth. Indirectly we also know that the center of the earth is very hot. After all, there are volcanoes and fumaroles, and the deeper you mine in places like South Africa the hotter it gets. Nearly everywhere scientists have measured temperature in wells, a thermal gradient exists: deeper means hotter. But we also know there is a lot of heat below us for several other reasons, including plate tectonics. SOMETHING has to be powering whole continents to be able to wander around. And then there's the magnetic field of the earth.

What distinguishes Earth from Mars and the Moon? A magnetic field, an atmosphere, liquid water - and life. The last requires the first three in our limited observations so far. Without a magnetic field to deflect it, Solar radiation would  sterilize the Earth and disrupt any attempt for life to gain a foothold. Solar radiation would also strip away any atmosphere, which is apparently why Mars doesn't have much atmosphere left to speak of. Mar's atmosphere is only a few percent of the density of our own atmosphere - though there is evidence of much more at one time in the distant past.

What distinguishes Venus from the Earth? Venus has an atmosphere, but it has fallen under a runaway Greenhouse Effect - too hot for water and in fact so hot that raw sulfur is a liquid on its surface. The Earth lies in what is sometimes called the "Goldilocks Zone" where it's not too hot and not too cold, between roasting Venus and frigid Mars. Water on Earth not only exists, but can exist in all three states (solid, liquid, and gaseous). This is not so for Mars or Venus, neither of which has a magnetic field, nor plate tectonics, nor significant water.

It has been apparent for quite awhile that the Earth's magnetic field is the reason why life exists on our planet. A magnetic field, however, requires some sort of dynamo to create and sustain it. How to power this? Well, if there are enough radioactive elements - or sufficient heat from the collapse of the proto-planetary disk to form our planet - well then maybe there is enough energy to drive a dynamo. However, this requires a lot of assumptions that scientists cannot test - they can't drill deep enough.

There is another problem: hot things tend to cool when surrounded by colder things... like interplanetary space. A magnetic field driven by an internal dynamo cannot last forever.

Hot things cool in two ways: by conduction and/or by convection. Conduction is like the metal pot you cook your cream of wheat in. Heat transfers from a hot source beneath to a cooler part above without any motion of particles involved. With convection, however - the bubbling cream of wheat - the heat is transferred by particles moving in three-dimensional loops called hydrothermal cells. You see them as bubbles driven by steam in the sauce pan. A hotter particle of the wheat from the bottom, in contact with the metal pan, rises because it is hotter (and thus less dense) than the particles above it, thus transferring heat from the bottom to the top of the cream of wheat. If the stuff cannot convect - if it's not liquid enough - then it will get hotter and hotter until it burns. It not only tastes terrible, but the sauce pan is a bear to clean up afterwards. In the same way, the solid iron core can only conduct heat out; like the metal sauce pan it cannot convect heat. However, the liquid iron outer core and the hot and plastic mantle above it can convect heat - and these convection cells of highly conductive material must be the source of the magnetic dynamo. The convection cells in the mantle are also what's driving whole continents around across the face of the Earth.

Remnant magnetization in rocks 3.5 billion years old, however, proves that the Earth's magnetic dynamo has existed for at least that long. The oldest known life is found in stromatolites - clumps of cyanobacteria - just about that old. This is not a coincidence. If there was no protective magnetic field, the stromatolites and then algae (and Earth's atmosphere) would not have survived Solar winds and radiation. But 3.5 billion years is a long time for something to stay hot enough to drive a magnetic-field-producing dynamo. Older computer models based on relatively low thermal conduction assumptions for iron seemed to suggest that it would take awhile for the solid iron core to give up its heat. This could conceivably sustain a dynamo lasting that long.  According to these older models, the heat from the core would take billions of years to conduct out to the outer liquid core and Mantle where a different form of heat transfer - the much faster convection - takes place.

In the last several years, however, scientists have been forced to re-evaluate what they think they know about the center of the earth. Several years ago, another piece of information became available from some Japanese extreme-high-pressure experiments. Iron at pressures and temperatures we calculate must exist in the center of the Earth has a far higher thermal conductivity than anyone had thought could be possible. According to milecular orbital theory, if you smash material together hard enough, it frees up electrons and changes its conductivity. This means that the Earth's heat-driven dynamo should have burned out billions of years ago. In other words, the Earth's magnetic field would have then died, and the atmosphere and any nascent life would have all disappeared before most of the geologic record could even take place. Think of dead Mars.

Speaking of geology, fluid and gas inclusions in ancient rocks tell us that around 2.5 billion years ago the Earth's primordial atmosphere of CO2 and nitrogen transitioned to an oxygen-nitrogen atmosphere. The world as we presently understand it began then. In part we can blame this on the stromatolites and photosynthesizing plant life that was expanding at that time.

In the 1970's a few scientists offered what seemed like a ridiculous idea: the Moon formed well after the Earth formed. It formed in its current size and shape when a large Mars-sized planetoid crashed into the proto-Earth and splattered material into space around the Earth. That material blasted into multiple orbits then coalesced to form the Moon, leaving a very different - and very hot - planet Earth behind. Computer models show that this is easily feasible. If so, then the Earth would have glowed like a small star from the massive infusion of heat from all the kinetic and potential energy of the collision. This idea is now taken seriously for several reasons, but mainly because the rocks on the Moon are sooooo much like the rocks on the Earth, and sooooo different from rocks on Vesta, Ceres, Mars, and Venus. We can discern these by optical spectroscopy, coupled with sampling meteors that the spectroscopy says must come from those places.

Could that ancient impact hold the answer for why we have such a long-lasting magnetic field around our planet? That seems to be the best explanation at this time. If so, then life exists on this planet because of some pretty amazing circumstances: 

• it exists in a narrow Goldilocks Zone, 
• it was given a huge heat boost by a collision from a large planetoid, and 
• its crust was given a lot of water from impacting comets that allowed it to be less solid, more flexible, and have an ocean of liquid water. 
• Photosynthesis then started early and gave this planet an oxygen-nitrogen atmosphere, and finally
• The Earth's magnetic field lasted a very, very long time.

Those are a lot of things that had to come together at just the right time for life to form and evolve here.

There are so many coincidences - like the Anthropic Principle that allows molecules - and thus life - to exist. It seems remarkably like our Earth has its own local version of the Anthropic Principle: just the right features and additions at just the right times to allow life to form and evolve over an extended period of time.

Bruce Buffett, a geophysicist at Berkeley puts it this way: "The more you look at this and think about it, the more you think it can't be a coincidence. The thought that these things might all be connected is kind of wondrous." (Discover, July/August 2014, p. 41)

With all the exoplanets being found in solar systems nearby in the Milky Way Galaxy, what is the likelihood that one of them could have all these coincidences? Since Galileo, humanity has been humbled to know that it isn't the center of the universe. 

However, it appears that we certainly are unique.

~~~~~

Windshield Time

NOTE: The following is a Q&A that stems from the post below it.

Q: Thank you very much. Your answer was more than adequate. Not only did you answer my primary question but also preemptively answered some follow-up questions I may have come up with.

My only remaining question is how the extremely deep oil reservoirs they are finding were formed. I've read some of the oil is at depths that would seem to pre-date the Carboniferous age.

I'm a plumber but I love pondering things such as this during my frequent "windshield time ". I appreciate you taking the time to explain this to me and to do so in a way I can understand.

Thank you very much,

- Patrick D

A: You can call yourself a "Plumber" if you want, but you are clearly and instinctively a natural scientist. That's the only definition that would apply to someone who ponders the world around them to such a deep extent during "windshield time" as you call it. I was involved on an expedition that crossed the Empty Quarter desert in Saudi Arabia and had two formally-designated scientists (we had PhD's). However, most of the other 15 expedition members got deeply into what we were trying to map at the Wabar asteroid impact site (Gene Shoemaker and I published this in an article in the November 1998 Scientific American). Our expedition companions first started asking questions, then offering ideas - and as a scientific TEAM we did the partial crater excavations and the surface mapping of the site. There were 17 people on that science team.

To answer your other question, there was carbon on this planet from its original formation. Some is magmatic in origin - things like carbonate volcanoes, more commonly called "carbonatites".  This is primordial carbon that is thought to come from the mid-to-upper mantle. There is a carbonatite in southwestern Afghanistan that stands out from the surrounding rocks both chemically and structurally like a big red flag. There is another, a real monster in southern Venezuela (Cerro Impacto is ~10 km across, but is NOT an impact feature). These things often have unusual levels of Thorium and Uranium in them, often in concentric zones. There are also Kimberlite Pipes - these are generally but not always tubes that carry diamonds up to the surface from the upper Mantle.

However, most oil & gas deposits come from sedimentary deposition of swamps and their occupants during ages that reach back as far as life existed. The carbon in the vegetation and animal life was buried to increasingly greater depths by later sediments. This usually happened in large basins, and the accumulating weight of these sediments often caused the basin to bow and get deeper in the middle. As an example of how fast this accumulation can happen, I was visiting an ancient mine site in the western Arabian peninsula. This was one of ~862 small ancient mines that provided King Solomon with his gold about 3,500 years ago. In that 3,500 years, dust and sand blowing across the Red Sea from the Sahara have buried the original mine site in nearly 4.5 meters (14 feet) of loess, silt and dust that we now have to dig down through to access the original shaft. And this accumulation was on flat ground! When surrounded by eroding mountains, a basin’s sedimentation can build up much faster than this.

With increasing weight overlying organic-containing sediments, both pressure and heat rise. Natural temperatures at the bottom of a 12,000-ft diamond mine in South Africa are about 60 C (140 degrees F). Eventually you get enough heat and pressure to "cook" the organic sediments - oil geologists call this process "maturation" among other things. When converted to a liquid these relatively less dense, carbon-rich fluids (oil and gas and water) tend to migrate upward, following weak zones in the sediments overlying them. They will do this until they either escape (the Gulf of Mexico is full of natural "seeps") or they get to a blockage that traps them: for instance some sedimentary salt from a dried-up ancient sea. THIS kind of natural trap is what the oil companies are looking for using sophisticated seismic prospecting and imaging systems.  

~~~~~

Seafloor Ooze, Subduction, and Oil

When I was a young man, I thought that having my PhD meant that I was now a scientist, that the advanced academic degree was somehow the dividing line between scientist and not-scientist. If I had been a little better at history, I would have realized that some of the greatest minds in science – people like Michael Faraday and James Clerk Maxwell – did not have PhDs. What they DID have was a tendency to think about things. The following two queries came from someone I call Patrick the Plumber Scientist.

Q: I've read the seafloor  "ooze" contains a fair amount of carbon based material. When this ooze is carried along with the seafloor downward in subduction zones wouldn't the combination of heat and pressure along with the presence of water form hydrocarbons aka oil?

- Patrick D

A: You are an unusually thoughtful person to arrive at that conclusion. Not all the ooze, as you call it, actually goes down with the subducting oceanic crustal slab – some of it gets scraped off and in some cases rafted onto a continental margin. You can find some of these strange remnants on the northern California and southwestern Oregon coastal area, among many other places in the rest of the world.

At some point the carbon from the seafloor muck that DOES go down with the oceanic crust probably passes through an oil/hydrocarbon maturation phase, but at depths and circumstances where it could not be economically extracted (even if it could be located). The muck continues down even deeper with the oceanic crustal slab to depths where even greater heat and pressure subsequently break it down to even more primitive constituents. With the water and sulfur also found in these seafloor sediments, this leads to partial melting – the lighter constituents rise through the crust (like a lava-lamp), somewhere in-board of the subduction zone to form volcanic chains like the Cascades, the Kamchatka Peninsula, the Andes, the Indonesian Archipelago, etc.

The magma that actually rises is driven at least partly by CO₂ and H₂S gases that derive from that original seafloor muck and seawater. These constituents, along with the iron, manganese, and silica of the Mantle, comprise the rising magma.  As it comes closer to the surface of the Earth, the pressure decreases and the gases come out of solution (like uncapping a bottle of soda) in that rising magma to form bubbles. This has been studied in one of our laboratories in a hot-high-pressure cell. The increasing nucleation of bubbles expands the magma volume and this causes the whole mix to accelerate upward faster and faster toward the surface. There it can often reach a runaway explosion that we call a Plinian eruption (named after Pliny the Elder, who died at Herculaneum trying to rescue friends during the eruption of Mt Vesuvius). This bubble-filled magma becomes a froth exploding violently upward into the atmosphere; it cools in the air to form the ash and tephra that (along with effusive lava) form the slopes of stratocone volcanoes like Mt Fuji, Mt Hood, and Mount St Helens.

Volcanologists work hard to measure and track volcanogenic H₂S (the burnt-match smell) and CO₂ gases to get a sense of where a restive volcano is in its possibly-pending, probably-not eruption. When Mount St Helens erupted in 2004-2006, it was relatively non-violent (though you would have died if you had been inside the crater at the time). An earlier almost-eruption in 1998 never quite reached the surface. Seismologists could see the volcanic conduit below MSH "light up" with the rock-breaking activity of a magma approaching the surface, but it never broke through. In the intervening 6 years, apparently these gases largely escaped, reducing the explosive danger from the volcano when it finally did erupt on October 1, 2004. One way to know if the CO₂ is volcanogenic, or from the modern atmosphere, is to measure its isotopic makeup. Atmospheric CO₂ has ¹⁴C ("Carbon-14"), ¹³C, and ¹²C isotopes. Volcanogenic CO₂ has only Carbon-12 (¹²C), the stable isotope in it. The other two radio-isotopes have long since decayed during the millions of years passed while the carbon was deep inside the Earth. 

~~~~~

When Will the World End?

I have received episodic queries asking if the world is about to end? Sometimes these correlate with apocalyptic movies being released. Sometimes they are triggered by an uneducated conspiracy theorist (an oxymoron) somewhere with nothing better to do than to look at seismic data freely available on the web. For instance, does the latest seismic activity in Yellowstone portend the end of the world? That one turned out to be an instrumentation issue not understood by the conspiracy theorist. Do the huge earthquakes off the coast of Chile and Japan mean that the End Times are approaching? We’ve all seen trailers for movies like “Volcano” (“The Coast is Toast”), and “2012”, and I have little patience with these attempts to make money.

But when will the world really end?  Or at least become unrecognizable to us, or even uninhabitable?

Current understanding of the evolution of the Sun suggests that it is about 5 billion years old and will likely continue burning for another 5 billion years. It may start fusing helium to carbon and turn blood red before then, but the time is so distant as to be irrelevant to us.

What about things heading south on somewhat shorter time scales? An article by Wolf and Toon (http://onlinelibrary.wiley.com/doi/10.1002/2013GL058376/abstract) suggests that there will first be a “moist greenhouse runaway” event, followed by the loss of all water from the surface of the Earth, followed by a runaway thermal greenhouse situation – like Venus is currently experiencing. The Sun increases its energy output by roughly 1% every 100-110 million years. In other words, it will continue growing slowly hotter on the planet Earth (see an earlier chapter on the Faint Young Sun Paradox here: http://askageologist.blogspot.com/2012/06/snowball-earth-faint-young-sun-paradox.html).

As solar output grows, the Earth’s surface temperature should steadily rise. When it does, water vapor concentrations in the lower atmosphere will increase, and this will lead to an increase in water vapor in the Stratosphere. Solar radiation there will break down water molecules, and the Solar Wind will then blow them away into space, leading eventually to a waterless surface.  This may be what happened to Mars billions of years ago, made to happen faster and earlier due to its weaker gravity. 

Some earlier research had suggested, based on computer simulations, that a “moist greenhouse runaway” process would start about 170 million years from now, and that a full thermal runaway (the “Venus Effect”) would start around 650 million years from now. However, Wolf and Toon factor in ocean-atmosphere moderating effects from those same surface waters, and calculate something more like 1.5 billion years before the onset of the “moist greenhouse runaway” event. 

Somehow I find this difficult to worry about.

What about bad things happening on shorter time scales? For instance, what is climate change really leading to? There is no shortage of either Climate Doomsday or Climate Rubbish prophets. A recent article in EOS (Transactions, American Geophysical Union, Vol. 95, No. 18, 6 May 2014, Wuebbles et al, link here: http://onlinelibrary.wiley.com/doi/10.1002/2014EO180001/abstract) provides several illuminating graphs included here for interested readers. Figure 1 shows the severity of weather in the United States on a decade-by-decade basis starting in the 1950’s. It’s hard to argue with a graph like this: climate change is clearly well underway (see the earlier chapter on Climate Change – is it real? Here: http://askageologist.blogspot.com/2013/07/climate-change-is-it-real.html).

Figure 1. Extreme weather events in the United States by decade since the 1950's (Wuebbels, et al., 2014).

Figure 2 actually lays out the consequences for climate change: what things will look like for different parts of the country for the 2070-2099 timeframe. A short summary: it all gets hotter (no surprise), and the precipitation generally increases (surprise), except for the southwest, where precipitation will decrease (no surprise). More and greater hurricanes are projected (no surprise), but the numbers of severe tornadoes and severe East Coast winter storms have not increased in six decades and may not with the increasing CO2 and methane in our atmosphere (surprise). The minimum temperature in Alaska will be between 12 and 15 degrees (Celsius) warmer – not bad for people like me who don’t like white stuff on the ground. Perhaps more surprisingly, the northern tier of the Continental United States will get warmest – by about 6-11 degrees Celsius by the end of the century. Mean precipitation will stay pretty much the same in the Southwest – but it will be 6-8 degrees Celsius hotter, leading to drier conditions even with that precipitation. This will make those Phoenix afternoons somewhat less survivable as the century develops. 

Figure 2. What we can expect, region by region, from climate change if CO2 and methane continue to be produced by fossil fuel consumption at current rates (Wuebbels et al., 2014). 

What about economic impacts? The American Breadbasket of the central and northern plains will be seriously threatened by increasing drought conditions. Perhaps we should stop wasting 10% of our corn crop for ethanol. 

What can anyone do on their own? You should consider investing in land in the Canadian Prairie Provinces – but NOT anywhere near a modern coastline. Estimates of seawater rise vary – but they are all on the positive side, and low-lying areas like the Jersey coast, Florida, and New Orleans will be the Big Losers. An attempt to rationalize flood insurance following Hurricanes Katrina and Sandy lasted just two years – then appeals to congresspersons for relief from dramatically increased flood insurance rates “won” again. The end result is that people are rebuilding in low-lying areas, and the American taxpayer will be expected to bail them out at enormous expense yet again.  Hurricane by hurricane. Science deniers apparently don’t believe in gravity, either.

Ultimately, if the world was going to end in 1,000 years, how would that be different from 1,000,000 years or 1,000,000,000 years? How would you change your life?

If you’re rational, you would not worry about the End of the World too much - unless you live on the Jersey Shore, or Florida, or New Orleans. If you are both rational and responsible, you would consider replacing your gas-guzzling SUV for something that gets better mileage. If you are still bothered, go help at a Sharing House for people who cannot get enough to eat, and you’ll feel quite a bit better afterwards.  

You will have increasing opportunities for this with time.

Aquamarine

Some people may be sitting on a gold mine – literally. I’m acquainted with some once-hard-scrabble ranchers in Arizona whose lands sat atop what would eventually become a gold or copper mine. They live in large houses and drive late-model pickups now. Other people may have stumbled on a rare fossil (a woman in Montana accidentally stumbled onto what turned out to be the most complete T Rex fossil ever found), or a rock that turns out to be a gem in more ways than one. 

Q: I have an aqua marine stone, approx 15 pounds . I would like to know it's value.

- Terry M

A: If you mean "aquamarine", then there are several possibilities:

a. a pale blue or greenish gem variety of beryl,

b. an aquamarine sapphire,

c. an aquamarine topaz, or

d. an aquamarine tourmaline.

15 pounds of any of these would be worth quite a bit, depending on the grade and quality. However, in the US Geological Survey we do highly applied research in geology and geophysics (some field offices work on ecosystems and biology). We have very specific line-item assignments in this agency, assignments set by Congress, and they do not include dealing with gem stones. As a result, we have never hired a gemologist per se as far as I know. 

I wish I could provide more help, because this is fascinating to me. In Bangkok, Thailand, there is a Wat (temple) that houses something called the "Emerald Buddha" that is apparently a carved statue of rough-grade emerald. In several senses of the word, this is a priceless artifact. Your stone would not be on par with this (it's not carved or sculpted I assume), but it is still worth something - if only as a source of material that gemologists can cut/extract high-quality raw gems from. 

You drank WHAT?!??

Most people have no clue where their drinking water comes from. I once contracted Giardia from a drinking fountain in Ocean City, Maryland, and after a pretty terrible week of vomiting and diarrhea, have been much more sensitive to what I am drinking. I’m also much more aware of where my water comes from. 

Q: Why is it important to clean and recycle water & where does drinking water come from i finally can hope that these only two questions can hopefully been answered and be removed of my mind. Kind Regards.
- Natalin I

A: There are many reasons why we need to clean and recycle water. Fundamentally, they all come down to the fact that there is relatively little naturally pure water left in the world. About 3.4 million people die each year from water related diseases.

Most drinking water comes from springs, streams, and rivers (surface water) or from wells (groundwater). In some places (such as NE Thailand) it is trapped from rainwater. However, all of these have potential problems. For example, if you collect rainwater from your roof, how do you keep birds off that roof?

In Saudi Arabia and a number of other arid and/or coastal countries, most drinking water is provided by immense desalination plants. As you can imagine this makes that water rather expensive. A side effect with this kind of water is that it is usually disposed of as waste into septic tanks... waste which seeps quickly into the local shallow groundwater. The groundwater in and around Jeddah, Saudi Arabia, for instance, is highly polluted with industrial chemicals and biologic contamination, and the groundwater levels are rising because of the dramatically growing human population. This polluted groundwater is now sapping building walls, and at least one hospital must pump water 24/7 out of the surrounding ground – and then dispose of it elsewhere so the hospital walls do not collapse. 

Consider surface water: if someone pollutes a stream near its source (e.g., cattle or other animals defecating), then everything downstream is contaminated. Giardia (sometimes called "Beaver Fever") and Clostridium (which shut down the Minneapolis city water supply for several weeks) are particularly nasty examples, and both are resistant to chlorination. In the 19th and early 20th Centuries, it was common for campers and hikers to drink stream water in the Rocky Mountains and Cascades Range with impunity. Not anymore: when I camp or hike I bring my own (safe) water, or a powerful micropore filter. Industrial feed lots or pig-raising farms are particularly dangerous offenders - major threats to safe drinking water. 

Now consider groundwater. I live in the (very wet) Pacific Northwest of the United States, and my groundwater comes from a well field deep under a large, 12 million-year-old basalt flow north of my city. The water originates as rain, and has been subsequently filtered by soil and basalt rock before it reached the aquifer where it is now pumped from. However, there are places in the US and elsewhere in the world where hydrocarbons (both NAPL and DNAPL forms), dioxins, and other terrible chemicals have seeped into the groundwater due to human carelessness: an abandoned gas station with rusting tanks, or a military base dating from the past century when waste was not thoughtfully disposed of. 

Recently, large parts of West Virginia have not had safe drinking water for weeks due to an "accidental" dumping of chemicals by a coal mine service company into a reservoir. I put "accidental" in quotes here, because the offending company has a long history of deliberately violating the Safe Drinking Water Act, including recent helicopter photos taken by CNN of highly illegal pumping and disposal of toxic wastes into nearby streams. In several places in the US, hydrofracking ("fracking") wells were not cemented in properly, and residents can literally light with a match the methane that has seeped out of their kitchen faucets. There are Superfund sites where highly carcinogenic dioxins, acids, and other exotic industrial chemicals have been released into the earth. These chemicals tend to move as plumes through the aquifers towards any well that is pumping water out of the aquifer. While biological contaminants can often be filtered (or boiled) out of drinking water, chemical contaminants that are in solution usually cannot. 

The United States and the Developing World have some of the highest standards on water quality in the world - but the large majority of the human population does not have these protections. There is a cholera epidemic in Haiti that has been going on for years, caused by fecal pollution of drinking water sources following the 2010 earthquake there. Cholera is a major childhood killer.

Here are several helpful websites that will guide you in your study of drinking water and pollution:
http://water.epa.gov/lawsregs/guidance/sdwa/basicinformation.cfm
http://health.usgs.gov/dw_contaminants/
http://water.usgs.gov/edu/groundwater-contaminants.html
http://www.unwater.org/water-cooperation-2013/water-cooperation/facts-and-figures/en/
http://water.org/water-crisis/water-facts/water/

I hope this adequately answers your questions(s).

Landslides

Catastrophes have a way of catching our attention. A single nearby disaster can lead us to believe that this is the only important threat to us. A case in point: the 1980 Mount St Helens eruption in Washington State killed 57 people, and led to a dramatic increase in volcano research and infrastructure over the ensuing years. Wildfires and floods were on the back burner for awhile in the Pacific Northwest, and people bought a lot of masks that were never used. However, as the technology resulting from the research spreads worldwide, it is becoming increasingly unlikely that a volcanic crisis will ever again evolve into a volcanic disaster.

Sometimes we do not want to learn the lessons. Just two hurricanes in the United States (Katrina and Sandy) killed between them around 1,100 people in 2005 and 2012. Yet people are rebuilding homes on exposed New Jersey coasts and below sea level in New Orleans as if these events never occurred.

More recently, the OSO/SR 530 landslide killed at least 35 people, with 11 still unaccounted for. How are we as a society going to react to this? We are riveted when a woman is devoured by a shark off an Australian coast (New South Wales, March 2014). However, the United States in 2012 had 34,080 traffic fatalities. This contrasts with more than 51,000 deaths in 1980, so it’s clear that if society focuses on a threat long enough, many deaths can be prevented. But do we expend our resources in mandating seatbelts, airbags, and speeding-and-texting enforcement, or do we construct hundreds of kilometers of shark fence? What is a proportional response to a rare, unforeseen disaster?

Q: I live in Australia, but heard of the recent tragedy in Washington State where many people were killed in a landslide. I have some family who live on a steep hillside in the Pacific northwest and am wondering if they are in danger and if it is possible to predict when a landslide will occur. Thanks

- David I

A: No matter where one lives, there is always what I call “locality risk”. If you live in the woods, there are opportunistic and hungry bears and cougars – but far more commonly there are rocks to slip on. If you live in a city, there are people driving over-sized SUVs while texting. I had a very close call last year with a lady combing her hair with one hand while using the other to talk on a phone. On a curve. Locality risk is obvious to people who live in eastern Australia (truly apocalyptic firestorms), the southeastern US (continent-scale hurricanes), the central US (Force 5 tornadoes cutting swaths more than a kilometer wide across entire states), and California (earthquakes to magnitude 7.2 are not uncommon). Every once in a while our attention is caught by a “new” surprise, such as the 1980 eruption of Mount St Helens in Washington State. Volcanoes? We have volcanoes in this country? In December 2004 relatively few people on the planet had ever heard the word “tsunami” – until 250,000 people died around the margins of the Indian Ocean from a single event.

Bottom line: There. Is. No. Safe. Place. 
In flood-prone areas, or in hurricane-risk areas, in earthquake zones, etc., one can buy event-specific insurance to garner at least some protection. However, these policy riders are always expensive, and usually have large deductibles.

Your query probably has to do with the “Oso Landslide” (technically, the “SR 503 Debris Avalanche and Debris Flow”) in Washington State, on March 22, 2014. I listened to a senior scientist in our office who worked there describe what happened, and his speculation as to why, and learned a number of new things about landslides in general, and the Stillaguamish Valley in particular. I learned that typically the landslide height-to-runout ratio - the height where the cut in the hillside began vs the distance from that cut to the toe where the debris flow eventually stops  is commonly greater than 0.3. However, the Oso debris flow moved nearly three times as far as it should have, based on a database of previous landslide events worldwide. It may have reached speeds of 100 kilometers per hour. It removed and displaced a large section of the Stillaguamish River from its bed, creating a blockage that built a temporary lake. I learned that this particular area had experienced small to medium landslides in the past. I learned that the region had experienced unusually heavy rainfall for months preceding the event. Most importantly, I learned that the surrounding hills were not Cascades Range volcanic rocks like most everywhere else in the region, but were instead a large glacial outflow terrace. In other words, a big pile of (wet) dirt and rock.

What appears to be new in this case – and perhaps the reason for the unusually long and destructive runout – is that these glacial terrace sediments apparently were perched on a layer of clay-rich ancient lake bed material. Under the shock of the initial collapse, this may have (along with the overlying water-saturated glacial material) been liquefied by increasing the water pore-pressure in the sediments. Clearly everything was water-saturated, because even after the event, investigators began calling one scarp face “the weeping wall.” This scientist who led our discussion directs a research group that uses 4D mathematical modeling, laboratory-bench-scale physical modeling, and a 90-meter flume to experiment with debris flows. Their research concentrates on how debris flows behave differently with different composite materials and water saturations – and how they start. With all their years of experience, these scientists are only just starting to get a "feel" for when a debris flow in their flume will begin... but it's still impossible to predict. The leader of this group may be the most experienced landslide/debris-flow expert in the world, and he told us that he had never seen or heard of an event before like Oso. 

Are your friends and family at risk?

What can they look for? Is there a lot of open ground up-slope from their house that could be exposed to heavy rain? Do their foundations anchor in any sort of bedrock - or just thick soil? If there are old trees in the area, do they have bases that appear to bend into the hillside? This latter is a sure sign of ground creep. If the slope above their home is mostly other houses, paved streets and sidewalks, and the trees above and below them are straight, they probably have little to fear.  

As discussed in an earlier chapter, we cannot predict earthquakes. We can generally predict tornadoes by a few minutes to hours, and hurricanes with perhaps a few days warning. We can forecast these if we have enough data on previous events, especially in the case of large regions like the southeastern US, southern California, or the San Francisco Bay Area. By forecast, I mean to provide a percentage likelihood that an event of a certain magnitude will take place within a fixed span of time (usually 30 years). Forecasting is different from predicting, however. Predicting implies foreknowledge of the where and the when of an event. It implies that a warning can be given (like a siren for an impending flood) and people can be evacuated beforehand. Ideally, a disaster can thus be mitigated to be “only” an economic crisis. Forecasting, on the other hand, is largely suited to inform building codes, emergency preparedness, and to calculate actuarial data for insurance rate purposes. It may help you make a better-informed decision about accepting a job somewhere.

One of the few destructive events that scientists CAN consistently predict in the medium to long term are volcanic eruptions – if the volcano is adequately instrumented. However, even this is imperfect – we can often predict an approximate time of an eruption, especially as the magma approaches the surface, but we do rather poorly when it comes to predicting size and duration of a volcanic eruption.

Can we predict landslides? 

No – no more than we can predict earthquakes. Can we forecast landslides? Not really – they are localized events, and not regional events where we can gather meaningful statistics. Each landslide is like a human or a bear – it has its own unique characteristics, or “personality.”

If you are living in a flat area, however, it’s probably safe to say you need not fear a landslide. With sufficient geological mapping, we can get a sense of whether a landslide is possible in a given area: Are there steep slopes nearby? Are the steep slopes hard rock like granite, or are they hydrothermally altered or mixed rock types like we commonly find in volcanic terrains? A more dangerous end member is something like the unconsolidated glacial terrace deposits surrounding part of the Stillaguamish Valley. It is even more dangerous if there is geologic evidence of previous slides in the area. It gets more dangerous still if the area is prone to earthquakes or heavy rains, such as in Los Angeles. And it could get even worse: if there has been a huge fire or clear-cutting, followed the next year by heavy rains (such as Vernonia, Oregon, in 2007), then you lose even the limited protection of vegetation anchoring the soil of a slope.

In retrospect, the Oso area had several of these risk factors: heavy rains, unconsolidated sediments piled 180 meters high, evidence of previous landslides. However, there had not been any recent clear-cutting, nor had there been a fire in the area. There had not been any seismic activity, nor any human activity that could have triggered the mass movement. It just happened.

Perhaps we can say that landslides/debris flows are a risk one assumes when building in a place with a nice view. A son and a cousin who live near mountains in different parts of the Los Angeles area each separately experienced a large wildfire nearby, followed the next year by large mudslides. Neither regarded the mudslides as worth much thought – but they were not living in expensive hillside homes, either. It was the smoke and flames earlier that caught their attention and distressed them the most. For both, the fire was the more immediate and palpable threat, even though both fire and landslides were probably equally as dangerous to human life.

Oso is apparently just one of those rare, remarkable anomalies that could not have reasonably been predicted. It just happened - in one tiny fraction of the all the landslide-prone areas in Washington State. Initial mapping suggests that it’s an isolated situation - the glacial outwash terrace deposits to not extend very far up or downriver from Oso. The area is being monitored now with helicopter-dropped USGS “Spider” instrument packages and time-lapse cameras, but these don’t help the 46 dead or missing. It may help protect the survivors - however it’s hard to imagine people rebuilding in this area. 

Your friends and family are probably as safe as you are – or anyone else.  

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