Showing posts with label Blue Cut Fire. Show all posts
Showing posts with label Blue Cut Fire. Show all posts

Sunday, August 21, 2016

The Importance of a Geology Education: Reflections on a Horrible Disaster in Louisiana (and others to come)

Hey, everyone! Raise your hands if you think a geology course should be REQUIRED of all students! [crickets]. Yeah, I thought so.

Geology classes occupy a somewhat uncomfortable zone within the standard college curriculum. Biology and chemistry are stand-alone majors, but they also provide important support to nursing programs and related health industries. Physics and mathematics likewise support numerous majors. But then there's that list of geology courses: they provide a pathway into employment in such diverse areas as oil and gas development, mining, water resources, parks interpretation, and education. But the number of geology majors is generally small in relation to other programs. And few students are really ever required to take a geology or earth science course as part of a different curriculum, with the occasional exception of a liberal arts degree leading to a teaching credential. Much of the time, geology courses mainly fill the role of general education breadth requirements, one choice among many.

Is there an argument for making geology classes mandatory in a college curriculum? Sure, for one good reason: geology can kill you. Oh sure, biology can kill you, given that whole disease thing, and pandemics, and grizzly bears and mountain lions.  Mathematics and physics can kill you, but usually in the context of a geologic disaster (or standing in the beam of a particle accelerator). I state this in a perhaps humorous vein, but with the burgeoning population of our planet, geologic disasters are becoming more and more commonplace. People are being forced to live in environments that are more and more dangerous, and the geologic events themselves are becoming more intense. Hurricanes and other weather events are being intensified by higher temperatures in the oceans and atmosphere, for instance. Earthquakes are not getting bigger (unless one lives in an area where fracking occurs), but with higher sea levels in the near future, the reach of tsunamis will increase.
Artist: Mark Waters, a student in the very first class I ever taught.

How far do we look for examples? This week I am watching dozens of fires burning through hundreds of thousands of acres of California, destroying hundreds of homes. Entire communities have been gutted. The fires are being intensified by an unprecedented drought entering its sixth year (the Colorado Plateau is in the fourteenth year of drought). At least 300 buildings have been lost in the Blue Cut Fire, but I wonder how many people in the area realize they are also living on the San Andreas fault, or that many of the homes in Wrightwood (in the affected area) are built on recent mudflow deposits?

And Louisiana...what can one say about Louisiana? It was just a rainstorm. A catastrophic 1,000 year rainstorm that dropped something like 2+ feet of water from the sky in just a few days. Tens of thousands of homes have been severely damaged, and people have died. A 1,000 year storm...a storm that has a 0.1% of happening in a given year. And yet West Virginia also suffered a 1,000 year storm in July. And there have been others.

My entire train of thought on this topic happened because I came across some articles that stated that only around a fifth of the victims of this week's flooding in Louisiana had flood insurance. My first thought was to wonder how in the world, in Louisiana, that this could be the case? There are many reasons, mostly financial (this is not the richest part of the country). But there are many other factors, too, and lack of education has to be one of them. Of course, there is the Mississippi and other rivers that flood regularly. But there is also the rise of sea level, and the subsidence taking place in the Delta. There are the changes in the intensity and timing of hurricanes and other intense storms due to climate change. People don't understand the risk of living where they choose to live (or where they are forced to live by circumstances). It makes no sense to skip on the insurance.

I then thought of California, where of course people are richer and better educated (please note, this is sarcasm, not a statement of fact). It took a few moments to find that only 17% of the residents of our state are covered by earthquake insurance (I strongly recommend reading the entire article). It's not hard to live in denial about the very real possibility of quakes in many parts of the state, but seventeen percent! Earthquake insurance can be expensive, but consider just why that is: these companies are not in the business to lose money, and their actuarial tables are probably a better indicator of the chances of earthquake damage than almost any geologic map (mind you, it's geologists who help calculate the odds that are used in actuarial tables).

People who live in ignorance also live in great danger. No place in the country is without the threat of some kind of natural disaster. One cannot realistically prepare for a cataclysm if one doesn't know that the possibility of the event exists. Education is the key, and it should be part of the curriculum of elementary and secondary schools as well as college. Community awareness, whether through social media or broadcast media needs to come from sources that are responsible and rational. There is so much CRAP on the internet that anyone could be forgiven for a sense of confusion. One group of ignorant people above all others who need an education in geologic hazards are the politicians. Science is almost never an issue in political campaigns (politicians seem to think we need to be more concerned with saluting flags and where people relieve their bladders). We need leadership at all levels of government to support community education, and to start dealing realistically with geologic threats and climate change (instead of denying that they exist).

Thursday, August 18, 2016

What's Burning Up Tonight: The Blue Cut Fire in Southern California

Source: http://www.fire.ca.gov/general/firemaps
California is burning. Sometimes, the fires are burning in unfamiliar places, places we've never visited. Logically, we know they are tragedies, that people are losing their homes, that beautiful forests are disappearing, but there's nothing quite like having a familiar place go up in flames.

Fires are part of the natural landscape, an outgrowth of a Mediterranean climate where no rain falls for six months out of the year. Plants and animals are adapted to fires. But things have changed, and some of the fires have become terrifying disasters. First of all, the growing population is expanding into ever more dangerous terrain, places that burn regularly, whether developed or not. But second, the effects of global warming are intensifying droughts that have left most of California dry and vulnerable.

The Blue Cut Fire is burning in an area I know well. I grew up at the foot of Lytle Creek and Cajon Pass, and have traveled over the pass perhaps hundreds of times over the years. The fire exploded in one day to more than 25,000 acres, and conditions offer little hope of any type of containment very soon. An unknown number of structures have already been destroyed, and an unprecedented 35,000 houses are threatened in places like Wrightwood, Phelan, and Lytle Creek. Something like 80,000 people have been evacuated. I hope and pray that it will be contained and controlled soon with a minimum of damage.

I wrote about the region a couple of years ago. Lone Pine Canyon is in the middle of the area that is burning, so the places seen in these pictures will be looking very different now. What follows is my post of March 31, 2013:

The Other California: Getting a Good Look at California's Faults

The San Andreas fault in Lone Pine Canyon near Cajon Pass in Southern California. Photo by Mrs. Geotripper

If there is anything that people know about California, it's the San Andreas fault. In a vague sense anyway...California has a lot of earthquakes that many people assume happen along the San Andreas (most don't), that there are occasional BIG ONES that happen on the fault (some of them, but not all), and if popular culture as expressed in movies like the original 1978 version of Superman reflects common knowledge, no one knows where it is or what it looks like (oh, and California is going to fall into the sea).
Still, the San Andreas is a fundamental part of the structure of California, and it is indeed capable of causing a great deal of seismic havoc, with some parts of the state considered at a high risk of moderate to large earthquakes. If one is curious about seeing the state's most famous fault line, there are a great many places to explore it, some in surprisingly visible locations. We are exploring one of them today in a segment of my "Other California" blog series.

Thousands upon thousands of cars follow Interstate 15 daily across Cajon Pass on their way to Las Vegas or their jobs in the L.A. Basin. I imagine few of the drivers know they are crossing California's most famous fault just a few miles north of the Interstate 15/Interstate 215 above San Bernardino. For a few moments, travelers are treated with a spectacular view up the linear track of Lone Pine Valley (the picture at the top of today's post shows the view, taken at 65 mph). I explored the lower end of Lone Pine Canyon and the "mysterious" Lost Lake (really not mysterious) in a post several years ago (click here to see it), but a weekend or two ago I had a chance to explore the upper end for the first time in a few decades.
The Mormon Rocks (or Rock Candy Mountains) expose the 18-20 million year old Cajon Formation. Interstate 15 climbs towards Cajon Pass on the skyline.
The road through Lone Pine Canyon takes off from Highway 138 about a mile west of the junction of 138 and Interstate 15. The road climbs through some beautiful exposures of the Cajon Formation  (the tilted exposures of the arkosic sandstones and conglomerates are called the Mormon Rocks or the Rock Candy Mountains; I've written about them before). The rocks have been tilted and folded due to their proximity to the San Andreas fault. The road surmounts a low pass and drops into Lone Pine Canyon.
The San Andreas fault is not a single break, but is instead a half-mile wide system of different slices of crust. Constant shearing over the last few million years by fault motions has left the rock fractured and easily eroded, forming the distinct linear valley of Lone Pine Canyon.
The series of fault blocks have formed a series of benches and scarps on the southwest side of the canyon, and a few offset channels are easily seen in the chaparral-covered hillsides (above).
Approaching the upper end of Lone Pine Canyon, we can see an odd hill in the middle of the valley. Looking at the steep slope to the right, it is apparent that we are looking at a rather large debris avalanche, caused no doubt by an earthquake along this stretch of the fault (above). The road skirts the lower end of the slide, confirming the nature of the hill with the broken and brecciated rock (below). There are plenty of candidates for the causative event; major earthquakes happened along this stretch of the fault in 1857(info here), 1812 (info here), and as many as a dozen other times in the last 1,500 years. There is a distinct warning in the earthquake history for this stretch of the San Andreas: the recurrence interval of large quakes is just over a century but it has been more than 150 years since the last major event.
The road reaches the top of the canyon, and a short walk along the ridge at the summit provides a spectacular view back down Lone Pine Canyon towards Interstate 15, and the two largest mountains in Southern California, San Gorgonio Peak and San Jacinto Peak. The fault passes between them on the way to Palm Springs and the Salton Sea.
 There is a large outcrop at the head of the canyon that exposes highly sheared rocks from the fault zone. The original rocks may have included the Pelona schist and granitic rocks but they are almost unrecognizable in hand samples.
But one thing is kind of cool: how often can you hold a major fault zone in your hand?
The road through Lone Pine Canyon ends in the village of Wrightwood, the subject of our previous post about a recurring mudflow originating in the Pelona Schist on the high ridges above. As if they didn't have enough to worry about...

The Other California is my continuing blog series on the geologically fascinating places in our fair state that don't always make it onto the tourist postcards.