Friday, January 29, 2010

Friday night observing - January 29

Short notice but if you read this before Friday night (January 29), go outside and look at the Moon.

Tonight's full Moon is at perigee - the point in its elliptical orbit closest to the Earth so it looks a bit larger than it does normally.

If you go outside around 8:00 pm, you'll see the full Moon in the eastern sky and, just to the left, a bright reddish "star" that's actually the planet Mars.

Go to Sky & Telescope for more information.

Yellowstone Update

On January 18, I posted about the ongoing swarm of earthquakes at Yellowstone National Park.  It's still ongoing and, over the last two weeks, there have been over 1,500 small earthquakes at essentially one location in Yellowstone!  Here's a real-time updated list from the United States Geological Survey (USGS).  Here's a map of Yellowstone, located in northwestern Wyoming, showing where the earthquakes are occurring.
The red line outlines the caldera - the large crater left by the last Yellowstone eruption some 640,000 years ago (there were other earlier ones as well).  Note the earthquakes are all occurring on the edge of the caldera.  While sesimologists are keeping a close eye on things, there's no reason to be worried at this time that these earthquakes are precursors to another eruption.

Earthquake swarms do occur at Yellowstone.  Last year, in December 2008 to January 2009, there were 900 earthquakes and back in 1985 there were 3,000 in a particularly large swarm.   All of these current eartthquakes appear to be located about 10-11 km in depth and aren't shallowing with time (as you might expect if they were caused by magma movement - something we don't want to see).

Anyway, seismologists at the USGS still believe these earthquakes are tectonic and not magmatic.  They're just stress readjustments along faults on the edge of caldera and no big deal.  Hopefully they're correct.

Thursday, January 28, 2010

More incorrect TV science

Watched a few minutes of Naked Science on National Geographic Channel tonight.  The show was titled Ice Age Meltdown.  They really should pay a geologist a couple of bucks to help edit these shows - there were a couple of inaccurate statements.

First some background.  Most everyone knows that the outer layer of the Earth is called the crust and it lies over the mantle.  Most people are also aware of plate tectonics, the fact that the outer layer of the Earth is split into rigid plates which move relative to each other over time.

Here's where some misunderstandings occur.  Many people knowing this much assume that the tectonic plates are composed of the Earth's crust.  It's actually a bit more complicated.  Below is a nice image I stole from a geologist's website via a Google image search.

There are two basic types of crust.  Oceanic crust, which is 5-7 km thick, is basaltic (essentially solidified lava).  Continental crust, however, is much thicker (averaging 35 km but thicker under mountains) and granitic in composition (mostly metamorphosed).  Below the crust is a layer of the mantle called the rigid upper mantle.  It's solid rock like the crust although it does have a different composition - it's called peridotite and is mostly composed of the mineral olivine.  Anyway, the crust plus the rigid upper mantle (which extends down to about 100 km below the surface) is called the lithosphere (from the Greek word lithos which means "stone").  The tectonic plates are made of the lithosphere.  Below the lithosphere is a softer layer of the mantle called the asthenosphere (asthenes is Greek for "weak").  The asthenosphere is not liquid, it's a soft solid that flows - think of Silly Putty.

Now how does this relate to a show called Ice Age Meltdown?   Well, during the last ice age (the Earth has had a number of "ice ages" in its history so you shouldn't say "during THE ice age), glaciers extended southward to their most recent maximum extent around 18-20 thousand years ago.  Thousands of feet of glacial ice is heavy.  Here is the mid-Hudson Valley of NY, it may have been a mile thick.  That depresses the crust - actually it depresses the entire lithospheric plate causing it to "float" lower in the mantle ("float" is in quotes because the mantle is not liquid).  This process by which the lithosphere is depressed when there's more weight on it and rises up when the weight is removed is termed isostasy.  It's one reason for local sea level change when glaciers grow and retreat.

So, on this "science" show, on the National Geographic Channel which should know better, they were discussing the crust and mantle of the Earth in relation to isostasy.  The crust rises and falls as it floats on the mantle.  OK, a bit of a simplification.  But then they mentioned, several times, how the mantle was magma and molten.  It's not liquid magma.  You can partially melt it to form magma under some conditions, like by lowering the pressure by thinning the lithosphere, but it's solid (you would never call Silly Putty liquid, would you?).

Is it too much to expect freshman geology accuracy from a supposed science show?  Students in my introductory geology class know better.

Wednesday, January 27, 2010

College Advising

Great quote on advising from Rate Your Students (a place for anonymous college faculty to bitch).

Advising is a key part of this mission. Our advisors take great care in helping students transition from the loving environment of high school into a world where nobody gives a shit about them. Although we can’t discuss the details of our patent pending advising methods (at least not until the 5th shot), it all comes down to giving each student an identification number and a course catalog. If the morons can’t figure out that they take Biology I before Biology II, then we can assume they won’t master the ATP-ADP cycle either.

Given the increasing hand-holding and mothering we're expected to give our adult students as advisors at my institution (with the bottom line of increasing retention and income), I had to laugh at the last sentence.

Science Channel Refuses To Dumb Down Science Any Further

Great satirical article in the Onion (which I love).  A quote:

Frustrated by continued demands from viewers for more awesome and extreme programming, Science Channel president Clark Bunting told reporters Tuesday that his cable network was "completely incapable" of watering down science any further than it already had.

Read it here.

TV, like public education, consistently caters to the lowest common denominator.  Even worse, many of the science and nature channels now air shows about bigfoot, UFOs, Mayan "prophesies", ghost hunting, etc.

Monday, January 25, 2010

Picture of the Week - Brachipods underfoot

This is a picture of my foot standing on a local outcrop.

The outcrop is located on the north side of Route 209/199 in Kingston just west of the Kingston-Rhinecliff Bridge across the Hudson.  There are four limestone formations present at this location - the Manlius, Coeymans, Kalkberg, and New Scotland Formations.  These fossils are in the New Scotland limestone (named after a town near Albany where this limestone was first studied).

The New Scotland limestone formed from shallow seafloor sediments deposited during the Early Devonian Period of geologic time some 400 million years ago.  Fossils of over 300 marine invertebrates have been recovered from this rock unit.  I'm standing on an ancient seafloor (now tilted about 30 degrees from horizontal).

If you looked at this rock bed close up, you would see that it's composed almost entirely of shell fossils.  These animals belong to a group called brachiopods.  They may superficially look like modern bivalves (clams, oysters, mussels, etc) but belong to an entirely different phyla - kingdom animalia, phylum brachiopoda for these fossils vs. kingdom animalia, phylum mollusca for the modern bivalves we're all famiar with from the seashoor or our dinner plates. Brachiopods are still around, but relatively rare.  Back during the Devonian Period, however, they were incredibly abundant and diverse.

It's easy to transport yourself back to the Devonian Period in your imagination.  Floating in a shallow sea miles from land (called the Helderberg Sea by modern geologists).  On the sunlit seafloor,  garden of brachipods floated in the currents attached to the seafloor with a fleshy stalk.  Shells agape, the filter fed from the plankton-rich waters.  Echinoderms and snails slithered through the sediments while trilobites swam above them.  The seas were warm and subtropical as New York was about 30 degrees south of the equator at the time.  Strange looking fish swam in these seas.  In some areas on Earth, life had started coming out onto land - primitive plants and insects with the earliest amphibians soon to evolve.

That's the neat thing about being a geologist.  For most people, it's just a gray rock on the side of the road that thousands of people drive by each day without giving it a second thought.  When geologists crawl around on that rock, however, we can read a story there and transport ourselves back in time.

Sunday, January 24, 2010

Satellite Spotting

Friday night, my whole family went out onto the back deck to watch the incredibly bright International Space Station (ISS) zip overhead passing close to the 1st quarter moon (to be honest, my kids were complaining because we ripped them away from a Nintendo DS game, but too bad, my wife and I enjoyed watching it).

It's easy to get satellite flyover predictions if you know where to look.  I use a website called Heaven's Above.

On the web site, you have to choose your location (the default is 0 latitude, 0 longitude - a location off the west coast of Africa).  You don't need to know your latitude or longitude, however.  Let's suppose you live in Stone Ridge, Ulster County, NY.  Under Configuration, click Select from database and you'll get a list of countries.  Select United States and then it asks you to enter your town name.  Enter Stone Ridge (do not enter the state).  The database will return a list of three Stone Ridges, two in New York and one in Tennessee.  Choose the one in Ulster County, NY (latitude 41.853, longitude -74.139 which translates to roughly 42 N, 074 W).

When you select your location, you go back to the main Heaven's Above website with data custom tailored for your backyard.  Let's see when the ISS will be passing over.  Under Satellites, click the 10 day prediction for the ISS.  Here's what I received for Stone Ridge, NY on January 24, 2010.

Sometimes you'll get a long list, sometimes a short one (like this), and sometimes nothing.  It all has to do with the orbital characteristics of the ISS.  I'll explain why this is so in a bit.  First note the header material at top.  One important piece of information is tht the times are all local time (Eastern Standard Time - EST) which makes things easy.  Note that today, January 24, the ISS will be visible starting at 5:08 (17:08:22 is 17 hours, 8 minutes, 22 seconds where 17 hours is 5 pm in 24-hour format).  The maximum altitude of the ISS will be at 5:11 pm, and it will disappear at 5:14 pm.  So the flyby will last about 6 minutes total.

Alt and Az refer to where the ISS will be at those various times.  Alt is altitude above the horizon where the horizon is 0 degrees and the zenith (the point directly over your head) is 90 degrees.  So, at its maximum altitude, the ISS will be 80 degrees up which is nice and high overhead.  Azimuth is simply the compass direction.  The ISS will initially appear in the west-northwest (WNW) and disappear in the southeast (SE).  So you do need to know some basic directions in your backyard to know where to look (this time of year, the sun sets in the southwest).

Also, note the Mag. column which reads -3.2 for today.  That's magnitude which refers to how bright astronomical objects appear in the sky.  The system dates back to the ancient Greek astronomer Hipparchus and the lower the number, the brighter the object.  Magnitude 6 is for barely visible stars (it's about the limit of naked-eye seeing), the north star is 2 (kind of average), Vega is 0, and Sirius, the brightest star we can see, is around -1.5 (negative magnitudes are brighter than positive ones).  Venus can reach magnitude -4.4 and the full Moon is around -12.7.  So, when the ISS is -3.2, it means it's brighter than the brightest star (Sirius) but not quite as bright as Venus at its closest - that's pretty bright!

Another neat thing about this ISS prediction is that if you click on the date, which is a link, you get a star chart with the ISS path on it (note how it passes close to the Moon again).

If your familiar with some of the constellations, this can help you spot the ISS as it moves overhead.  Try it sometime, it's a fun thing to get the prediction, go outside, and then actually spot the ISS (there's people up there in that tin can!).  The Heaven's Above website also gives other satellite predictions so even if the ISS isn't visible there is always something you can look for (although they won't be as bright).  It's neat to see a satellite and tell people that it's SeaSat 1, an ocean observation satellite launched back in 1978.

So why can we see satellites?  They don't have lights on them like planes do but instead they are orbiting so high up that for an hour or so after the sun sets and an hour or so before it rises in the morning, the satellite is up in bright daylight while we're in darkness on the ground.  Light reflects off the metallic surfaces of the satellite making it visible to us.  The ISS orbits the Earth every 90 minutes or so but we can only see it when it passes overhead during those windows of time.  If it's overhead in the middle of the night, we simply won't see it because it's in darkness too.

Friday, January 22, 2010


Just read an interesting book about seahorses – Poseiden’s Steed: The Story of Seahorses, from Myth to Reality by Dr. Helen Scales – a marine biologist from Cambridge who obviously loves them.

Well worth reading if you want to know more about seahorses – everything from how difficult they are to classify taxonomically to how they’re used in traditional Chinese medicine to how images of them appear as the Rainbow Serpent in 6,000 year old Australian Aboriginal images.

One of the interesting things I learned in the book had to do with seahorse reproduction. I knew male seahorses carried the babies in a special pouch but didn’t know how it worked (scientists didn’t really know, in detail, until recently either).

During the courtship dance, the female seahorse inserts her ovipositor into the male’s brood pouch and inserts some eggs. The male seahorse then ejaculates sperm into the water which must then find its way into the brood pouch to fertilize the eggs. The male then carries the fertilized eggs until they develop into baby seahorses (the only male in the animal kingdom that truly gets pregnant and gives birth to young).

Grotesquely pregnant seahorse from Wikipedia

The interesting thing about this is how inefficient this process is. It would be a much better design to have the male release the sperm directly into the brood pouch with the eggs (because the sperm are exposed to the open water, they’re also exposed to pollutants in the water these days). But nature isn’t designed (intelligently or otherwise). This process is the product of its evolutionary history. Seahorses and their pipefish relatives evolved from fish like sticklebacks (or, more correctly, sticklebacks and seahorses had a common ancestor).

Seahorses release sperm into the water because that’s what their ancestors did when fertilizing fish eggs laid outside the body. It’s an evolutionary holdover from its past. Just another of a million examples of evidence for evolution we see in the natural world (read Your Inner Fish: A Journey into the 3.4 billion year history of the Human Body by Neil Shubin for many more).

Another interesting fact – seahorses are monogamous. Probably due to the fact that they’re poor swimmers, not very common, and spend most of their life attached by their tails to a piece of seagrass. Once you find a mate, it makes sense not to wander off since it’s hard to find another.

Interesting little critters.


My wife and I have two children, fraternal twins, a boy and a girl, soon to turn 9 years old.  We homeschool.  I always feel a bit reticent to admit it because some people are openly hostile to the concept (usually due to bizarre misconceptions about what homeschooling is or why we do it).  It is, however, something I feel strongly about so I'll occassionally post about it here.

As any homeschool family can tell you, the number one question people ask about homeschooling is "What about socialization?"  Don't be surprised if a homeschool family laughs at you if you ask that question because it's so stereotypical and also a ridiculous question for most of us.

First off, it’s a somewhat insulting question if you think about it since it implies we lock our children in a closet all day. No, we're not raising wild wolf children and if you saw them on a playground they're not standing by themselves against a wall somewhere.

Socialization is teaching children the skills to function as a member of our society. How to interact with other people.  Much of that should be taught by the family anyway - things like manners (some parents today apparently neglect teaching this to their children), the concept of sharing, appropriate and inappropriate things to say, and modeling good behavior in front of them among other things.

Other skills the children pick up on their own from interacting with peers. Granted that does happen in a school environment but it also occurs with homeschooled children. Our kids play with other kids too.  Homeschool parents are always getting together for play dates, field trips, and various learning activities.  Our kids have participated in a homeschool orchestra (learning to play instruments), a homeschool chorus group, gymnastics (mixed kids), karate (mixed kids), Cub Scouts, drama class, writing courses, art courses, outdoor activities held by the Mohonk Preserve and Lake Minnewaska State Park, etc.

Some of the kids our children interact with are homeschooled, others go to public or private schools. The real difference is that our children interact more with children of different ages (because when homeschool families get together, they bring all their kids which may range from infants and toddlers to young teens.  Another difference is that they're interacting with kids at these activities who want to be there and participate.  There are not a lot of problems with disruptive kids ruining it for everyone - something that occurs all the time in public schools.

There is one thing our kids aren’t exposed to and that’s the Lord of the Flies environment that sometimes develops in a public school environment. My kids have never been mocked and ostracized for not wearing the “right” clothes or sneakers (which is good because homeschoolers swap hand-me-downs all the time). I still remember being in middle school and having some people mock me because my jeans were too baggy (tight jeans were “in” then) and didn’t have a designer label (they came from Sears).

My kids have never been afraid to ride a school bus or go to school because someone constantly beat them up. I had that problem before I hit puberty since I was a skinny kid who liked to read.  When I hit 8th grade, and had a growth spurt, I exploded in rage one day over the constant harassment and slammed a kid's head into the locker.  People left me alone after that.  I have a coworker that once told me he thought I was wrong to protect my kids from bullies because they have to learn how to deal with them.  I disagree - no one should be terrified to go to school because of bullying.

Now I know some people reading this may think I'm just projecting my experiences onto my children who may not have those problems.  I'll offer two things to counter that.  First, I know several teachers at our local school districts - as a community college professor, I've even taught some of them.  Bullying, sexual harassment, and drug use is rampant in our local schools.  Secondly, my son is skinny, very smart, shy, and bookish.  I have no doubts he would be picked on in school.   My daughter, being more social and outgoing, would probably do well but I'm afraid the type of socialization she'd get at school is that science and math are not appropriate for girls (being homeschooled, she doesn't know she's supposed to like Hannah Montana more than learning about how to train rats - her current interest). 

I think parents who send their kids to public schools should worry more about their children's socialization because much of what they learn to value (and not value) from their peers is warped, at least in my opinion.  Then again, I feel the same way about our celebrity-obsessed, anti-intellectual culture which I suppose places our family as a whole out of step with most of society.

By the way, if you're worried about how well my children do academically, they take the same standardized tests your children do and I'd match their scores against public-school kids any day.

Finally, I love this Bitter Homeschooler's Wish List.

Thursday, January 21, 2010

Surgery - A follow up...

Was wheeled into the operating room a bit after 8 am, woke up around 9:45, and was home by 2 pm.

Other than the pschological aspect (being very nervous), it was pretty easy.  A bit stiff and sore and I have four holes in my abdomen, but otherwise OK.  I've only taken tylenol so far even though they gave me some Percocets if I need them.

Hopefully, this will clear up the stomach pain issues I've been having for a while now.

Tuesday, January 19, 2010


A personal post... 

I had some stomach pain before Christmas that got very annoying.  I thought I might have had an ulcer.  Went to the doctor between Christmas and New Years and he told me it sounded like my gallbladder.  Scheduled an ultrasound for the first week of January and, lo and behold, a gallstone in the neck of my gallbladder.  Gave me the number of a surgeon whom I saw next week and in two days (Thursday) I get to have surgery.  A little less than a month from start to finish.

Unfortunately, the best treatment for gallstones is to have the gallbladder removed (cholecystectomy).  Ignoring the problem will usually result in the gallstone eventually blocking the bile duct, causing intense pain, and needing emergency surgery (never good).  So, under the knife I go.

I'm a little freaked out because I've never had surgery before (I've been lucky, I guess) and never even had ansesthesia for anything other than novacaine for dental work.  Hopefully, they'll be able to do the operation laparoscopically with relatively small incisions and a quicker healing time (most people go home the same day).

If you have a strong stomach, here's a YouTube video of the procedure.  Can't resist adding this too, it's the first in a series of articles about gallstones from a surgeon's blog.  Wish me luck!

Monday, January 18, 2010

Yellowstone tremblers

Yellowstone National Park has been trembling with over 200 earthquakes over the past few days (today's January 18).  Here's a list and map of some of them.  Nothing too large so far and nothing to worry too much about yet. 

Last year, in December and January of 2008/2009, there was a swarm of over 800 quakes under the north end of Yellowstone Lake with no large earthquakes.  The recent swarm is over on the west side of the Yellowstone caldera near the Montana/Idaho border.  It's also close to where the largest swarm ever recorded occurred in 1985.

Yellowstone does have a potential for very large earthquakes.  On August 17, 1959, a magnitude 7.3 occurred during the height of summer tourism season and killed 28 people.  Most probably also know (courtesy of TV Supervolcano hype) that Yellowstone has had inconceivably large volcanic eruptions in the past as well!

Odds are, this swarm will settle down in a few weeks.  You never know, though, and a large earthquake would not surprise geologists at all.

Picture of the Week - Stromatolites

The picture below is from Lester Park, a small roadside rock outcrop a few miles west of Saratoga Springs, NY (here's a brochure from the NYS Museum with directions).  Note the Swiss army knife for scale.

The fossils visible here on this bedding plane of 500 million-year-old limestone (the Cambrian Hoyt Limestone, to geologists) are called stromatolites.  In life, these fossils were made by mats of colonial cyanobacteria - they're sometimes called blue-green algae but they're not algae.

Here's a picture of modern cyanobacteria from Wikipedia.

Looks like pond scum.  Even though it's bacteria, it photosynthesizes - water, carbon dioxide gas, and sunlight are used to create sugars and release oxygen gas as a waste product.

Some 500 million years ago, this area of New York was submerged under warm, shallow water (New York was around 30 degrees south of the equator at this time).  On the seafloor, mats of cyanobacteria happily photosynthesized.  With ocean currents sweeping seafloor sediments around, sediment grains stuck to the bacterial mats.  The bacteria grew up to the top of the sediment layer.  They were buried.  They moved up.  This occurred over and over again to form mounds of finely-laminated structures which eventually became fossilzed as stromatolites.

The first picture showed an eroded rock layer which cut a horizontal plane through the stromatolites.  Below is a picture showing a cross-sectional view as well.

Given their shape, these fossils are sometimes called "cabbage heads."

Besides being neat fossils, what's the significance of stromatolites?  Well, they date back to almost 3.5 billion years - the oldest fossils on Earth - and are still around today.  They were the dominant reef-forming organisms for a couple of billion years until the evolution of multicellular life (while colonial, cyanobacteria are single-celled without a nucleus).  While rare today, they still exist in a few environments - most famously in a location called Shark Bay in western Australia (picture from Wikipedia).

Even more importantly, at least for us, is that cyanobacteria are mainly responsible for Earth's atmosphere changing from one dominated by carbon dioxide gas (like modern-day Venus and Mars), to one with 21% or so molecular oxygen.  We can actually see oxygen levels rising during the reign of cyanobacteria in Earth's ancient oceans since oxygen is so reactive and leaves evidence in the minerals and rocks preserved from those times.

If it wasn't for that ancient "pond scum," we wouldn't exist.

Sunday, January 17, 2010

Geologists & Beer

OK, this story's about a month old, but I can't resist being both a geologist and beer aficionado.

Why Geologists Love Beer at Wired Science.

That is one thing I miss from my grad school days - Friday afternoon colloquia and beer.

Saturday, January 16, 2010


Excuse me as I make a foray into local social issues today.

The city of Newburgh has been in the news lately.

On January 13, there was a story in the Mid-Hudson News about how Newburgh was going to participate in Orange County's gun buyback program on Saturday, January 16.  Bring your gun down to the police station and they'll give you a Shoprite supermarket gift card worth up to $150.
A few hours after this story appeared, a 13 year old stabbed and killed a 17 year old on the streets of Newburgh at 4 in the afternoon.  A number of other kids were involved in the fight and witnesses reported some of them had "clubs."  The local newspaper reported that the school district was going to close all its schools Friday in response (not stated, but obviously worried about violent gang retaliations).
Pretty ironic.  The same day the story appears about a gun buyback program - whose aim is to reduce street violence - kids stab each other to death.  Maybe we need a knife buyback?  Of course, we all know the kids would then beat each other to death with clubs.  Buy back clubs and they'd hit each other in the head with rocks.
It's not the weapons - it's the people.  I grew up in this area.  When I was a kid, I brought my pocket knife to school (Rondout Valley) every day and no one cared (no one stabbed each other either).  I still carry a Swiss Army knife every day, like most geologists, even though it probably technically violates my college's "weapons" policy.  It's a tool I use almost every day (I fix things a lot).  When I was a kid, everyone had a BB gun by the time they were 10 and many had .22 rifles by the time they were 14 and deer hunting at 16.  I can't remember anyone ever shooting anyone else.
Today, New York State makes law-abiding citizens jump through hoops to legally own a pistol.  The process takes 6-8 months, involves photos, fingerprinting, and judge visits, and costs a couple hundred dollars.  Every pistol is registered.  When, where, and how you can carry or use your pistol is governed by a strict (albeit sometimes confusing) set of laws.

Are we safer because of this?  Has gun violence been reduced?  Of course not.  All it does is inconvenience people who would be far more likely to protect you with their pistol than shoot you.  Just the opinion of a card-carrying NRA member who enjoys shooting a .40 Glock (and who thinks the 2nd Amendment to the Constitution is still relevant today).
We don't have a gun problem in this country (or a knife problem).  We have a social problem - a subculture of sociopaths that we try to regulate with laws.  Only problem is that sociopaths don't obey laws.

Tuesday, January 12, 2010

Big earthquake in Haiti

A magnitude 7.0 earthquake occurred today on Tuesday, January 12 at 21:53:09 UTC (4:53 pm EST).  Location was 18.45° N, 72.45° W - about 15 km (10 miles) southwest of Port-Au-Prince, Haiti.  The depth was about 10 km (6.3 mi), a relatively shallow earthquake.

The earthquake basically occurred on a fault (the Enriquillo-Plaintain Garden fault system) associated with the boundary between the North American plate and the Caribbean Plate.  The Caribbean plate is moving eastward by about 20 mm/yr (0.8 in/yr) relative to the North American plate (geologists would refer to this as a left-lateral strike-slip fault).  It sticks, stress builds, then it snaps and moves.

This is a bad one.  Whatever minimal infrastructure Port-Au-Prince had is now likely gone.  The death toll from the quake and its afteraffects will be horrendous.

Picture of the Week - Taconic Unconformity

The image below shows a rock outcrop on Route 23 west of Catskill, NY in the mid-Hudson Valley.

So what is this showing?  There are two distinct rock units here.  On the right are interlayered gray shales and sandstone and the beds are tilted such that they are almost vertical.  On the left are beds of an orange-brown rock called dolostone which are tilted about 45 degrees from horizontal.  There is a distinct contact between these two units running from the lower-left to the upper-right of this picture.

Shale is made primarily from quartz and various clay minerals (lithified mud).  Sandstone is made from quartz (SiO2).  Dolostone is basically limestone (calcium carbonate or CaCO3) with some magnesium tossed in -- (Ca,Mg)(CO3)2.  They're very different types of rocks.

Geologists call the unit on the right (the older one, since it's below the other), the Austin Glen Formation and they call the unit on the left (the younger one), the Rondout Formation.  It's actually very easy to distinguish them from each other in the field (they look more different in person than they do in the image).

This contact, where the Rondout Formation lies on top of the Austin Glen Formation and they both have different orientations is not just seen here. You can drive to other locations in the area to see this as well.  Geologists call this type of contact an angular unconformity.

Fossil evidence in the Austin Glen indicates it's from a period of time called the Middle Ordovician Period (let's say 465 Ma).  The Rondout Formation is from the Late Silurian Period (let's say 420 Ma).  That means that there's some 45 million years missing in that unconformity!  Missing rock strata indicates from that from around 465 Ma to 420 Ma, this area was undergoing a time of erosion - there were no sediments accumulating to later form rock layers.
A very basic principle in geology, first formulated in the mid-1600s by Nicolaus Steno in Italy, is that of original horizontality.  What this means is that sediments originally accumulate in horizontal layers which then lithify into horizontally-bedded sedimentary rocks.  If the layers are tilted, such as the one's above, then some force later tilted them.  Another of Steno's principles is superposition - the basic idea that in layered sedimentary rocks, the oldest layers will be at the bottom.  Pretty simple.
So what does the outcrop above tell us?  An entire sequence of events...
1.  Around 465 Ma, the Austin Glen Formation was laid down as marine muds and with periodic influxes of sands in horizontal beds in a deep basin (the fossils tell us this).  They gradually accumulated and were buried.  Over time they lithified into shales and sandstones.
2.  Sometime between 465 and 420 Ma, the Austin Glen rocks were tilted by some type of event.  Looking at numerous outcrops reveals that these layers were actually folded and cut through by faults due to horizontal shortening in a present-day east-west direction.
3.  Around 420 Ma, the Roundout Formation was deposited as horizontal sediments in a shallow, tidal-flat environment in a hot, arid climate.  Eventually these sediments were buried and lithified into beds of dolostone.  At this time, the angular unconformity existed between the Rondout and Austin Glen Formations but it too would have been horizontal.
4.  At some time younger than 420 Ma, Everything was folded and faulted yet again by another shortening event (again in a present-day east-west direction).
In other words, what this outcrop represents is two distinct tectonic events.  We know, from studying metamorphic and igneous rocks to the east, that these were huge mountain-building events.  To form each of the rock layers, tilt them twice, erode them flat, etc. will take very long spans of time - in this case tens of millions of years.  Some time later, I may discuss these but the post is getting long enough as it is.

One last thing I'll mention is that in 1788, a Scottish physician and amateur geologist named James Hutton saw an outcrop at Siccar Point on the coast of southwestern Scotland.  At Siccar Point, tilted strata of red sandstone dated around 345 Ma overlie almost vertical strata of graywacke (a type of sandstone) dated around 425 Ma (80 million years of missing time).  It's almost exactly analagous to the Taconic unconformity in Catskill.

Siccar Point from Wikipedia
Back in Hutton's day, they didn't know the ages of these rocks, but Hutton did recognize that such an outcrop showed an immense span of time.  To create such an outcrop through naturalistic processes would have taken far, far longer than the traditional 6,000 year Biblical age of the Earth.  It was the beginning of modern geology.
I could keep going for pages but I guess I'll stop here and pick this up another time.

Monday, January 11, 2010

Watch out for engineers

Interesting article in Slate titled Build-a-Bomber asking why so many terrorists have engineering degrees.  A study by two sociologists, Diego Gambetta and Steffen Hertog, has shown engineers were three to four times more likely to become violent Islamic terrorists than their peers in other disciplines.

I found this interesting because of a phenomenon called the Salem Hypothesis which holds that there is a correlation between being a leader in the young-Earth creationism movement and having an engineering degree.

From the Slate article:

"Gambetta and Hertog write about a particular mind-set among engineers that disdains ambiguity and compromise. They might be more passionate about bringing order to their society and see the rigid, religious law put forward in radical Islam as the best way of achieving those goals."

Substitute "conservative Christianity" for "radical Islam" and the above statement makes just as much sense.  I'm not trying to denigrate engineers, just noting that otherwise intelligent people who have an absolutist mindset about religion might be drawn more toward academic fields with little ambiguity.

Or this all may just be complete bullshit.

Sunday, January 10, 2010

Jupiter & Galileo

Arriving home tonight around 5:30 pm, I saw a bright "star" low in the southwest sky.  Jupiter.  At magnitude -2, it was brighter than the brightest star - Sirius (which rose about an hour later).  I noticed recently that January 7 was the 400th anniversary of Galileo Galilei's observation of Jupiter's moons in 1609.  In Sidereus Nuncius - Starry Messenger, published in 1610, he wrote:

Galileo was the first to see moons orbiting Jupiter.  Why was this significant?   In 1543, a lifetime earlier, Nicolaus Copernicus proposed his heliocentric system - the model postulating that the planets all orbit the sun (in opposition to the classical geocentric model which held that everything orbited the earth).  Around 1605, Galileo's time, Johannes Kepler was modifying the Copernican model to ellipical orbits rather than circular ones.

Galileo's observation was a strong piece of evidence against a strict geocentric model of the solar system - here were objects orbiting something other than earth.  This use of the telescope by Galileo was the beginning of the end for the geocentric model.  Unfortunately, the Catholic church at the time held to the geocentric model as being the one in accord with the Bible.  And the Catholic Church in early 1600s Italy was not to be mocked.  By the way, Martin Luther, leader of the Protestant Reformation, also disbelieved the heliocentric model of Copernicus so it wasn't just the Catholics.

As an aside, there are lots of similarities here between 17th century geocentrists and modern-day evolution deniers. Both claim that a clear, literal reading of scripture supports their position.

Here's what you'd see if you looked at Jupiter's moons tonight (January 10) using a neat Javascript utility from Sky and Telescope.

The I, E, G, and C stand for Io, Europa, Ganymede, and Callisto - the four Galilean moons of Jupiter from closest to furthest from the planet. Tonight you would see Io on the left and Ganymede and Callisto on the right (Europa is in Jupiter's shadow).  In a couple of days (January 12), the view would be:

Io still on the right with Europa (now visible), Ganymede, and Callisto (must closer now) on the right.  Every night will show a different view.

Here's what it looks like through a telescope (from Wikimedia Commons).

A never-ending dance of light as the moons orbit Jupiter.  In 1676, Danish astronomy Ole Romer even calculated the speed of light from the movements of Jupiter's moons (maybe I'll write about that sometime - it's a cool story).  I also have my students in astronomy class do an exercise (Project CLEA) where they calculate the mass of Jupiter from the orbital periods of the moons.  It's amazing what you can learn by just observing (and a little thinking).  Too bad there are still people opposed to that (see the above comment about creationists).

Full-time vs. Adjunct Faculty

The New York Times had an article on Dec 30 about The Case of the Vanishing Full-Time Professor.  The article says that in 1960, 75% of college faculty were full-time and either tenured or tenure-track while today only 27% are.  The rest are graduate students, adjuncts (part-time faculty only teaching 1-3 classes each semester), or contingent faculty (typically on year-to-year contracts with no job security).

While the New York Times may have just noticed this, it's certainly not news to those of us working in academia (or many college students who pay attention to who's teaching them).  At the community college where I teach, we've had between 60-65 full-time faculty over the past few years (varies semester-to-semester based on retirements, new hires, and those out on sabbatical).  We also have around 150 or so adjunct instructors (which varies semester-to-semester as well).  Almost a three-to-one ratio of adjuncts to full-time.  I'm not sure what the numbers looks like if you look at the percentages of course sections taught by full-time vs. adjuncts since full-time faculty teach 5 course sections each semester (although several faculty have course reductions for being department chairs or coordinators) while adjuncts may teach 1, 2, or 3 sections (but no more than 3 for contractual reasons).  To figure this out for a specific semester, I'd have to print out all course sections for the semester and count it up (which I don't feel like doing today).

So why is this a big deal?  Well it's great for the bottom line of the college.  Adjunct faculty have no protections (you can decide whether or not to use them up to the first day of classes), they receive a lower rate of pay (and professors are paid poorly to begin with given their education), and they have no health or retirement benefits.  Cheap labor.

There's a downside for the college as well.  Full-time faculty do a lot more than simply teach.  They serve as department chairs and program coordinators.  They do periodic program and course evaluations required, in our case, by the State University of New York system in Albany.  They develop new programs and courses.  They serve on various committees which determine academic policy, hear student grievances, and plan the future direction of the college.  They advise and register students each semester.  They do research.  They engage in professional development.  They give talks and lectures outside of their classes.  Just a few examples.  That's why college faculty will laugh at you if you suggest they only work a couple of hours a day since those are the only times their classes meet.  It's not uncommon for me to work 50-60 hours a week.

Adjunct faculty generally do none of these things.  They typically come in, teach their course, and maybe hold one office hour a week.  Many adjuncts also teach at several colleges to try and make ends meet meaning they're spending much of their day commuting.  At our school, which is typical, adjuncts in each department get a large closet and a single computer shared with a dozen other people and it's called their "office."  They're often treated as 2nd class citizens - usually not intentionally, but simply because it's too hard to include them in the culture of the department when they're never around.

What's the downside for students?  As a department chair, I try my best to make sure that our adjuncts are good teachers.  We don't have to hire an adjunct each semester so if they're not good, why use them?  The real problems are harder to address.  The problems students have with adjunct instructors typically result from three things:

- Adjunct faculty can't interact with students as much as a full-time instructor can.  They come in, teach their class, and leave.  They have no advisees to develop relationships with during the student's time at school.  They are typically harder to reach (especially in person) when a student has a problem with the coursework.

- Adjunct faculty aren't as invested in the college as full-time faculty.  I want the college to do well and succeed.  I want to uphold academic standards.  I want a healthy enrollment.  I've invested years of my life here and I want to spend years more.  Adjunct faculty, often treated poorly by the college administration, don't have nearly the investment in the college.  If they're not teaching one class here, they'll pick it up elsewhere (or work at Wal-Mart for almost the same rate of pay).  If an adjunct faculty member feels a conflict between upholding the academic integrity of the course or making it easier to teach (and not catching flack for failing too many students) what do you think they'll do?

- Adjunct faculty often aren't as up-to-date in the subject matter as full-time faculty.  Many have other (even full-time) jobs out of academia.  They don't go to professional conferences or participate in professional development.  They don't often read journals in their field.  They don't often do research or write papers.  With each year, especially in areas like science, they fall further behind the cutting edge.  This matters, even in an introductory freshman-level course.

It's important to note that these are all generalizations.  I know adjuncts that I would hire as a full-time faculty member in a heartbeat and we'd be fortunate to have them.  I also know full-time faculty that I'd love to fire.  But I will say that, in general, it's better for students to attend a college with a higher percentage of full-time faculty.  That said, I don't think my institution is doing too badly.  If a student takes general physics at my community college, for example, they will be taught in a small class (max 30 students or so) and both lecture and lab will be taught by a full-time faculty member with a PhD in physics.  If they take the same course at a nearby state university, they will sit in a large lecture hall, never interacting with the professor, and be taught in lab by a graduate student (who may have no experience teaching and possibly poor English skills based on my undergraduate experience 25+ years ago).

I do fear, however, given the dire fiscal situation our idiot New York State government has gotten us into, that as full-time faculty retire over the next few years they will only be replaced by adjuncts.

Saturday, January 9, 2010

Earliest tetrapod trackway

PZ Myers over at Phyrangula has a good summary of a recent paper about the discovery of what appears to be the oldest tetrapod trackway on Earth pushing the origin of amphibians from lobe-finned fish back some 20 million years to around 395 Ma - the early part of the Middle Devonian Period.  The transition of vertebrates from sea to land has become a bit more complicated than we thought.

Nied┼║wiedzki, G., Szrek, P., Narkiewicz, K., Narkiewicz, M., & Ahlberg, P. (2010).
Tetrapod trackways from the early Middle Devonian period of Poland.
Nature 463 (7277), 43-48

Friday, January 8, 2010

The sad state of science journalism at Fox News

Fox News has a January 7 Science & Technology news story titled "Cataclysm that killed dinos still taking lives today."  I can not believe this was published by a major news organization.  Some excerpts from the news story...

"The tremendous volcanic eruption thought to be responsible for Earth's largest mass extinction — which killed more than 70 percent of plants and dinosaurs walking the planet 250 million years ago — is still taking lives today."

There was indeed a mass extinction 250 million years ago (Ma).  It was called the Permian extinction since it marks the end of the Permian Period of the Paleozoic Era of geologic time and the start of the Triassic Period of the Mesozoic Era.  This is a fundamental division in the geologic time scale (placed there because the fossils show this huge extinction event and a big change in the type of life present on Earth).

Problem is, there were no dinosaurs around at this time - none.  A lot of people think that there was only one mass extinction in the past and it was the one which killed off the dinosaurs (this was the K-T extinction which occurred between the Cretaceous Period of the Mesozoic Era and the Tertiary Period of the Cenozoic Era - another fundamental break in the geologic time scale that occurred about 65 Ma).  In reality, there have been numerous mass extinctions with the Permian one being the worst.

Bottom line... Prior to 250 Ma, there were only reptiles (no dinos).  Permian mass extinction 250 Ma.  Dinos evolve and rule earth for some 180 Ma.  K-T extinction 65 Ma.  No more dinos.  Big difference.

By the way, the Permian extinction was even worse than the quote above makes it sound.  The 70% estimate is only for terrestrial vertebrate species (not nonexistant dinosaurs).  One group of terrestrial vertebrates greatly effected by this event were the therapsids - also known as mammal-like reptiles (reptiles which eventually evolved into the mammals).  Well over 90% of marine species became extinct as well (think about that for a minute).

Now I can understand non-scientists (and my students) not knowing about the Permian extinction.  But a journalist and an editor at a major national news organization writing for the Science & Technology section?  I'm not one of those knee-jerk "Fox News sucks" people - hell, I think CNN and MSNBC suck too - but in this case, they do indeed look like morons.

Reminds me of our local newspaper.  Once, when we offered a night telescope observation on my Campus open to the public and once when they reported on an event on Campus called Science Olympiad, they confused astronomy with astrology.  When confronted with this, the editor basically said "Don't make such a big deal out of this, it was just a typo."  No, sorry.  Typing "astronony" is a typo. Typing "astrology" is ignorance.  To a science person, saying "XX Community College is offering a night astrology observation on Friday" is a glaring error that just jumps off the page.  Of course, the paper (like most in this country) carries a daily astrology column but barely ever covers astronomy (or any other science except health-related ones).

Next excerpt...

"Scientists investigating the high incidence of lung cancer in China's Xuan Wei County in Yunnan Province conclude that the problem lies with the coal residents use to heat their homes. That coal was formed by the same 250-million-year-old giant volcanic eruption — termed a supervolcano — that was responsible for the extinction of the dinosaurs. The high silica content of that coal is interacting with volatile organic matter in the soil to cause the unusually high rates of lung cancer."

Coal is not "formed" by volcanic eruptions.  Coal is basically buried and compressed plant material.  And don't get me started on the term "supervolcano" - it's an invention of science journalists and media-whoring geologists who want to be on TV.

The real story here is actually quite interesting.  About 251-250 Ma, huge volumes of basaltic lava erupted in the area that's now Siberia and resulted in an area called the Siberian Traps (traps is derived from a word meaning "steps" because sheet-like lava flows often erode into step-like plateaus).  These basalt sheets cover a few million square kilometers - a vast area of the landscape.  During the extrusion of this lava, there were also associated pyroclastic eruptions of ash that reached the stratosphere and were spread around the world.

Some of this ash, composed of very fine particles of the mineral quartz (silica), settled into swamps and peat bogs in what's now China.  This silica was buried with the plant material and it all formed into coal that's mined today.  Chinese laborors burn this coal for fuel in their homes and it releases the silica back into the atmosphere where it's breathed in and seems to cause increased rates of lung cancer.

A neat story.  One that Fox News totally screwed up.  Wired magazine has a much better story - Chinese coal formed during earth's greatest extinction is deadly.

Monday, January 4, 2010

Picture of the Week - Clove Valley

Photo of the week...

I took this picture during the summer from a location called Cope's Lookout on the Mohonk Mountain House property.  Mohonk Mountain House is a beautiful (albeit expensive) resort located on the Shawangunk Ridge in the mid-Hudson Valley.

The Shawangunks (locally pronounced "shon-gums") is a NE-SW trending ridge arising in Rosendale (Ulster County) and running past Port Jervis into NJ/PA on the east side of the Delaware River.  On the east side of the Shawangunks is the Wallkill and Hudson River Valleys and on the west side is the Rondout Valley and Catskills.  The geology of the Shawangunks is interesting but I'll save that for another post - suffice to say that it's composed of rock (Shawangunk Conglomerate) of a different age than the rocks underlying the valleys on either side of the Ridge.

This view from Cope's Lookout is facing roughly SW along the Ridge.  On the left, a bit of the Wallkill and Hudson Valleys can be seen to the SE.  On the east side of the ridge are cliffs popular among rock climbers (the "gunks" are actually world-famous for rock climbing). The land surface slopes downward from the tops of these cliffs into Clove Valley in the center of the image.  On the other side of Clove Valley, the ground rises up again.  The reason Clove Valley exists is because the Shawangunk Conglomerate underlying this valley is folded into a syncline - a downward-sagging fold.  Imagine holding a flat sheet of paper between your two hands and pushing your hands toward each other until the sheet of paper buckles downward into a U-shape - the beds of Shawangunk Conglomerate did the same thing here.

Hiking on the rocks on the east (left) side of Clove Valley shows that the layers (beds) of rock are dipping downward toward the west (into Clove Valley).  Hiking on the rocks on the west (right) side of Clove Valley shows that the beds of rock are dipping downward toward the east (also into Clove Valley).  It's actually possible to hike throughout most of the area visible in this image because the land is owned by the Mohonk Preserve and accessible after paying an entrance fee or having a membership (highly recommended if you live in the area).  The land in the distance is part of Lake Minnewaska State Park (also highly recommended for a visit).

Below is a cross-section of the geology of the mid-Hudson Valley from Regional Geology of Southeastern New York State for Teachers and Travelers by J. Bret Bennington of Hofstra University.

See where it says Lake Minnewaska?  That's the top of the Shawangunk Ridge and the layer of rock with dots in it is the Shawangunk Conglomerate.  Note how it's a bit "wavy" where it's exposed at the surface?  Those are folds and one of the downward warps (a syncline in geology) is the Clove Valley!  The Shawangunk Ridge is exposed where it is due to a combination of folding and the fact that it's a harder, more resistant rock than the shales under the Wallkill Valley to the east and the limestones (primarily) under the Rondout Valley to the west.  The great glacial ice sheets moving down the Hudson Valley during the last ice age (which ended just a few thousand years ago) also played a huge role in shaping the landscape we see today.

The underlying geology obviously affects the present-day shape of the landscape.  The geologic history (e.g. glaciation) also clearly affects the present-day shape of the landscape.  But, less obviously, the underlying geology can also affect the flora and fauna of the region.  I'll discuss the unique ecosystems present on the Shawangunk Ridge at a later date.

Climate Change and Scientific Behavior

Just read an interesting article on Climate Change and Scientific Behavior by Diandra Leslie-Pelecky over at Cocktail Party Physics.  I feel the same way that Diandra does. As a community college Earth science professor, I teach classes in weather and climate even though my area of expertise is geology (more specifically, structure / tectonics).  I'm not, by any stretch of the imagination, a climatologist, yet I have to teach students about global climate change.

Don't get me wrong, I know enough about paleoclimate proxies, stable isotope analysis, solar cycles, natural and anthropogenic CO2 sources, basic atmospheric chemistry, etc. to teach my 100-level course, but I also want to understand the data, assumptions, and models used to predict anthropogenic global warming over the next few decades.  I would like to be able to confidently discuss the effects of warming - sea level rise, changes in oceanic thermohaline circulation. glacial melting, etc.

The problem is that the issue of anthropogenic global warming (AGW) appears to have become heavily politicized.  Simplistically, Democrats "believe" in AGW and Republicans do not.  The issue's "settled."  Anyone who questions any aspect of AGW is a GW "denier."  Scientists who publish studies critical of AGW need to be silenced and the journals who publish those papers need to be punished.

Silly me, I thought science wasn't about "belief," openness was an essential part of the process, and a little skepticism was a good thing. So, while I certainly think the evidence indicates AGW is real, the other bullshit surrounding the issue disturbs me.  I'm guess I'm just a naive idealist. It makes me want to shy away from the issue completely.  Just teach the kids the basics of chemistry, physics, etc. necessary to understand the arguments and then hand them the latest IPCC report.  Problem is that some of them (the smart ones, at least) then want to know what I think.  Damned if I know.