Hope your National Fossil Day was Great!

I wasn't able to comment earlier in the day, so in these last seconds of National Fossil Day, I hope you had a nice one! I am especially impressed with the logo for this year, as it includes a mosasaur, a ferocious late Cretaceous creature that once swam in the seas that existed right here in California's Central Valley when it was still a shallow forearc basin between the Sierra Nevada magmatic arc and a massive subduction zone. Mosasaurs were reptiles that were broadly similar to Komodo dragons which adapted to a seagoing life. The largest exceeded 30 feet in length. I suspect they made sharks nervous...

In California, We Are Waiting for the BIG ONE! True or false? What everyone "knows" about earthquakes

Comic art by Zeo

We've reached the end of our seven question quiz on what everyone "knows" about California earthquakes, things which may be true or maybe aren't. These questions were the basis of a community lecture I gave a few weeks ago. The last two questions concerned the ability of psychics and animals to predict earthquakes, and yes, psychics are frauds when it comes to earthquake prediction, and we can't sense the world the way animals do, so basically, it is impossible to predict earthquakes in the kind of timely manner that will allow people to take cover or leave town. We just can't do that, not yet.

But there is still that nagging statement that you hear all the time in California. It's today's true-false question:

In California, we are waiting for the BIG ONE! True or False??

When I was on stage at the lecture, I made sure to say "the BIG ONE" in capital letters. How do you say something in capital letters? You do it in a deep baritone voice with your hand cupping the microphone; it's very dramatic.

So what is the answer? Well, actually the question is wrong and requires a bit of modification. Let's try it again, and in that deep baritone voice:

In California, we are waiting for the BIG ONES!

There, that's better. If we can't predict earthquakes, then how can this statement be possible? Doesn't it require the ability to predict earthquakes? Yes, it does. So the statement must be false. But it is not. The answer is TRUE!

Predicting earthquakes is not possible in the short term, as in hours or days, but a great deal can be said about the probability of earthquakes in a particular area over a period of decades. We can do this on the basis of the historical and prehistorical record of earthquakes along a particular fault zone, and by analysis of building stresses and tilting over a large region, as revealed by GPS stations and other related technology Check out the methodology of the 2007 Working Group on California Earthquake Probabilities in this USGS PDF file.

As can be found on the map above, numerous fault zones represent a threat to the state of California. The fault zones are of different lengths, and therefore some will produce smaller quakes, but several are capable of producing large shocks approaching magnitude 7, and maybe even larger. These include the San Jacinto fault, the Owens Valley fault, the Hayward and Calaveras faults, and others. Even more important is the fact that the San Andreas itself is not a single monolithic fault zone. It has segments that behave independently. This was shown in 1857 and 1906, when completely different sections of the fault gave way, producing shocks that approached magnitude 8.

The most recently published studies show that earthquakes of 6.7 magnitude or greater are a virtual certainty over the next 30 years. The chance for an even greater quake is ominous, exceeding 70% for a magnitude 7.0, and a lesser, but still significant chance of even larger events. In a way, one of these quakes has already occurred, even though it was just south of the state: the El Mayor-Cucapah quake this year in northern Baja California was a magnitude 7.2 event.

Another wild card is the possibility of a large quake along the Cascadia subduction zone in the northernmost part of the state. It was not included in the probabilities, but numerous magnitude 7 quakes have taken place in that region in recent decades.

The lesson to be drawn from these predictions is that damaging earthquakes have happened all over California, and they will continue to do so in the future. Some of these quakes will be major events, causing many deaths and massive damage over large areas. The probability forecasts have great value in the sense that they are a warning to residents across the the state to be prepared at all times for earthquakes. We cannot know the precise moment that a large earthquake will strike, but we do know where they will happen, and how big they can be.



Building the Perfect Impregnable Fortress in a Volcano: How to Take Over the World

It started with an entry at the Geological Society of London blog: Top 5 Volcanic Lairs for Evil Geologists, and a description of where one would make plans for world domination. It was an interesting list, and some of your lesser evil geologists might want to make use of them. But Eric Klemetti at the Eruptions blog said "pfpt", and suggested that Erebus in Antarctica was the ideal base to launch an evil plot. He made a strong case, including the use of penguins as henchmen and evil minions. Batman's enemies were certainly onto something there, but there is a problem: penguins can't hammer and drill (no opposable thumbs and all). Who was going to build the impregnable fortress? Jessica at Magma Cum Laude had some other great suggestions, but her evil geologists have the same problem:

How can you build a giant high-tech impregnable fortress without catching the attention of the local authorities? Where do you get all the supplies without raising eyebrows among the tax men and union bosses? How can one avoid paying for medical benefits and retirement plans for all the henchmen and minions? I mean, it's not like they are gonna work for minimum wage when their lives are likely to end in a hail of bullets and fireballs. Although maybe they think, given the economy, "it's a job"...

I think I have a solution to the dilemma. Mt. Shasta in Northern California. Here's the thing: the mountain is just full of a ready-made army of henchmen and minions who won't be asking for wages and benefits. Heck, they've been off the economic grid for thousands of years.

A short list of the inhabitants of the interior of the volcano includes the Lemurians of Mu who come with their own uniforms (white robes), and have a "walnut-sized organ in the center of their foreheads" that does extra-sensory...things (these descriptions are courtesy of Stephen Harris, author of Fire Mountains of the West, from Mountain Press). There are the survivors of Atlantis, of course, and their high technology. There is the Secret Commonwealth and their cities of Iletheleme and Yaktayvia. Their tunnels and passageways were carved with odd supersonic vibrations from bells. I have to imagine that it is indeed getting crowded down there (as Harris says), and they would jump at the chance to follow some evil geologist into world domination.

Any additional supplies that are needed are not a problem: UFOs have been landing on Shasta for years, taking advantage of the lenticular clouds that often form around the summit. Supply helicopters can do the same thing. Or one can ally with the aliens, too.

Of course, Shasta is kind of a famous volcano, perhaps the most famous in our state. If you want to use all the minions from Shasta, have them tunnel forty miles northeast to Medicine Lake Highland, California's biggest volcano. It is a vast shield-like basaltic edifice that is practically unknown even to Californians. It is barely half as tall as Shasta, but much more voluminous. There is lots of room for everyone to spread out.

Anyway, if I were an evil geologist bent on world domination, that's what I would do...

Cancel Columbus Day...or make it something better...

This picture and the "Cancel Columbus Day" caption landed in my facebook account, and I think it is a great sentiment. I agree there are better things to celebrate...not only was it the start of the near-extermination of a continent full of people who had already "discovered" the land, but the guy was on a commercial venture. The holiday is an outmoded tradition that is meaningless to most people, and grossly insulting to many people. One could argue that we need a holiday for many reasons: religious beliefs account for a few (which also celebrates one group over another), and important national events are another (we celebrate Memorial Day so we can thank our family members and friends who served in the military). And in a capitalist country that has come to dishonor the workers who make the oligarchy rich, we still hang on to Labor Day. We remember the birthdays of people who brought out the best of our country: Washington, Lincoln, and Martin Luther King. I find this appropriate.

How about celebrating a true moment of national exploration? One that changed everyone's perception of the planet? It seems to me that if this country values science and technology as an accomplishment of the human spirit; conquering disease, improving standards of living, and journeying where no one has gone before, then we should have a day that celebrates our nation's greatest scientific adventure. My thought is that we should set aside the day we landed on the moon in 1969. Our country set a communal goal with JFK's speech at the beginning of his presidency, and against huge odds we succeeded. Admittedly, the race to the moon involved trying to outdo the USSR, but I doubt that fighting communism was the foremost thought of the scientists and engineers who got us onto our planetary neighbor. And the effort resulted in vast advances in science across many fronts (not the least of which was geology).

I don't care much for Columbus. We should be celebrating something truly meaningful, and I think science should have such a day. What do you think?

Fall in the Sierra Foothills

It's California, so the season "fall" doesn't always have the same panache that it might in the northeastern states or northern Rocky Mountains. It also comes a lot later. Except for the (somewhat) unusual inch of rain we had last week, these days would be largely indistinguishable from summer. Dry, dusty, and only a little bit cooler (highs in the eighties are expected this week).

Still, it did rain last week, so the air was cooler today, and there was a freshness we haven't felt in months. We took a little picnic this afternoon up the Tuolumne River into the Sierra Nevada foothills. We stopped at Old Basso Bridge, a river crossing that was once the focus of some rather intense gold dredging. Numerous ponds from the mining days dot the landscape, filled with groundwater. Today they provide habitat for wildlife, and a nice recreational area for fishing and wildlife photography.

The old Basso Bridge was replaced with a sleek modern concrete edifice that dominates the view from the boat ramp, but a short walk provides a view downstream towards the old bridge (which is closed to autos, but available for pedestrian use).

The old dredge ponds provide a surprising sight for this time of year: lots of flowers. There were hundreds of what looked like Brown-Eyed Susans.

The other interesting sight at the park are the boulders they've used for rip rap to reinforce the base of the bridge. They are chunks of a deeply oxidized conglomerate that is found locally in a layer called the Ione formation. It formed in Paleogene time as rivers flowed over the not-quite risen Sierra Nevada. The rivers had their source in central Nevada or more distant regions, and flowed through a landscape much different than that of today.

The rivers ended in an estuary/delta complex along the Pacific Ocean (the Central Valley was a shallow sea at the time), and in a series of swamplands that later produced lignite coal that was utilized during the settlement of California after the Gold Rush. Fossils of palms and other warm weather vegetation indicate tropical conditions.

The conglomerates also contained significant amounts of gold (hence the local dredging activity). There were a couple of guys panning gold today, and they actually had come up with 20 or 30 pinhead-sized flakes.

Fall is just beginning. I'm looking forward to some color (of the leafy kind) in the next few weeks!

Animals Predict Earthquakes! True or False...What Everyone "Knows" About Earthquakes

It's question 6 of 7 on the topic of what everyone "knows" about earthquakes, those things that are "known", but which are not necessarily so. It was the subject of a public lecture that I gave last week. The question of the day is:

Animals predict earthquakes...true or false?

The audience was pretty firmly on the side of "true". My answer to this one?

??? Who knows???

The problem is perceived cause and effect. Many people who experience strong earthquakes recall strange behaviour by their animals, and link that behaviour to the quake. The problem is that animals may behave strangely in many circumstances that are not followed by a strong earthquake, but the behaviour is not noticed or remarked.

This animal is clearly predicting an earthquake. Or is about to attack.

The other problem is how to quantify strange acts by animals. What specific animal behaviour constitutes a prediction of an earthquake? At what point do authorities declare that animals have predicted a quake?

There are many anecdotal stories about unusual activity by animals going back hundreds of years, so I for one cannot completely dismiss the idea out of hand. Animals sense the world differently than humans, and there could in fact be some sort of electromagnetic or vibrational effect that researchers have not yet detected.

A reasonable response on earthquakes and animal behaviour by the U.S. Geological Survey can be read here, and a good article by the National Geographic can be found here. Geologists around the world have been following a story coming out of Italy regarding the failure of seismologists for failing to predict or warn the local populace before a deadly earthquake in Italy that killed several hundred people in 2009. It's one thing to say geologists can't predict earthquakes, and quite another to say they didn't predict it enough in the aftermath. Seismologists walk a fine line.

Speaking of kitties and strange behaviour, if you see these eyes, run for your life. Aliens have taken over your cat's soul....

Kick Off Earth Science Week with Wild Planet Day, Saturday October 8

For my Modesto area readers...

Earth Science Week starts on October 9 and runs through October 15 and lots of activities will be taking place all over the country. Here in Modesto you have a chance to get a jump on the festivities by attending a great science event at Modesto Junior College tomorrow on October 8. In addition to all the wildlife related events (see the press release below), the MJC Geology Club and Department will be offering activities including mineral identification, stream tables, geology by microscope, and displays will include a working seismometer, and fossils, including dinosaur bone, shark teeth, mammoth bones, and our rarely seen sabertooth cat. We will also be giving away free rock, mineral, and fossil samples for those who want to get a collection started!

Check the press release below on this great event!

"Wild Planet Day" Science Fest to be held at MJC

 

The Modesto Junior College Great Valley Museum and Science, Mathematics and Engineering Division are hosting a family oriented Science Fest with the theme “Wild Planet Day” on Saturday, October 8 from 10 a.m. to 3 p.m. The event will take place in and around the Science Building on the corner of College and Coldwell Avenues on East Campus. Admission for the day is $8 per person or $25 per family of 4, with no admission charged for children under 3 years old.

This fun-filled fest will include live animal presentations, hands-on science labs, telescope and planetarium viewing and geocaching, a popular hide-and-seek game using global positioning system (GPS) devices. Participants can observe a wildlife show featuring a kangaroo, eagle and monkey, live reptile presentation or wild animals from the Stanislaus Wildlife Care Center. There will be squid and owl pellet dissection, pumpkin carving and 4-H animals. Science enthusiasts can enjoy over 30 fascinating hands-on science labs including DNA extraction and make-your-own-lung.

The event is a fundraiser for the Great Valley Museum, a non-profit foundation dedicated to providing science and natural history information to adults and children of all ages through classes, programs and exhibits. The museum serves the families of Stanislaus, San Joaquin, and surrounding counties. For more information on the Science Fest call (209) 575-6739.