GEOLOGY/GEOPHYSICS 101 Program 29

Living With Earth I

We try to ignore the fact that we are part of the physical world, and we try to pretend that we're somehow separate from the planet. At the same time we try to pretend that the planet is both bountiful and boundless. This is kind of strange when you consider that we're fully aware all the time that we know that we depend upon the planet for all of our needs: air, water, food, heat, shelter, personal good, everything.

And we also find that many people don't even know the fundamental facts about the Earth, things like the sun rises and sets in a different place every day in a yearly cycle, or why the days are shorter in the winter, or why there are faces of the moon; in fact, I've come across students in my classes who don't even know that there are phases of the moon. Now, how separate from nature can you get? But at the same time, you see, we try to modify our environment to make it less unpredictable for our use. We also pretend to forget that change is the norm, and that constancy is a short term phenomenon at best, especially when we consider geologic time, and when disasters do occur, we pretend to be surprised by them. We ignore the warnings that are given to us, and when we are warned or when we don't ignore the warning we behave irrationally.

You might recall the behaviors that we talked about during the tsunami warnings in the 1950s here in Hawaii, so today's lesson covers actually four major segments.

There'll be segments on

• volcanism,
• earthquakes,
• floods, and
• mass wasting,

and we can't cover all of these things, so you're going to have to rely upon the text and the study guide, and this lesson's a little bit longer than some of the other lessons and might require a little bit more time.

The text assignment's kind of complicated, but just take it one step at a time, one segment at a time, and it shouldn't be too bad so be sure to look in the study guide for the text assignments for each of the sections, okay, and follow the plan in the study guide.

Note that this plan is different from the other lessons and be sure to read each of the four summaries, and then go back to the learning objectives in each of the four sections, and make sure you've learned each one. Well, for this program I want to focus not on specific hazards.

The text and the study guide do that together quite adequately, and the video cites a special case of a certain earthquake in North California, so what I'd like to do is today focus on our attitudes toward geologic hazards and their prediction. You know, geologic hazards generally are simply events which threaten our life or our property, and we generally live with these hazards at the same time as we try to learn more about them. We also try to predict them and control them, and generally we don't have much success at either. We know that certain types of geologic events are more likely in some places than others; for example, volcanoes don't occur randomly but are concentrated around plate boundaries on the Pacific Rim and the Mediterranean Sea, and also in hot spots like we have here in Hawaii, but we also know that each volcano or each type of volcano has a particular pattern or at least characteristic which may be somewhat predictable.

We know, for example, that Hawaii volcanoes are traditionally gentler than continental volcanoes which tend to have more explosive character. We also recognize that geophysical methods of various kinds can be used to help us and aid us in predictions. Seismographs can record harmonic tremors, and gravitometers can locate magma chambers.

The St. Helen's eruption in 1960 was forecast, and some of the results were predicted although the exact time wasn't, and it's been said that many lives were saved, but there was still much loss of life from the eruption of Mt. St. Helens because people either refused to leave the area or were unaware of the risk and didn't get the warnings.

Okay, for the other hazards, we also know that earthquakes occur in certain regions, for example, active mountain building regions at plate boundaries, and in those places volcanoes may be associated with them or not. Floods and mass movements also are more likely in some areas than others, so all of these hazards, we can help in understanding and learning about these hazards if we understand them first as geologic processes, and then once we understand them, they can help us to identify the areas in which these things are most likely to occur, but even knowing this, the loss of life and property damage worldwide is considerable and in a given year from a combination of all of these hazards, so what do we do? We clean up. We rebuild. And life goes on.

Well, today to help us focus on the issues, I've invited a special guest. Dr. John Babson is a man of many hats. He's an eagle scout, has degrees in chemistry and physics, and he has also a background in geology and cultural anthropology, and he's very well read in both human ecology and oriental philosophy. He teaches a course here at HCC called "Earth in Universe," where he gets a chance to put all these various things together and espouse on some of his favorite topics, and I think having him with us today can provide us with a lot of insights and a kind of a different perspective, but a good perspective on our relationship with our planet.

Well, nice to have you with us, John.

<John> Thanks. Nice being here.

<Rick> Well, let's get down to it here. Why do you think we insist on living in these areas where these geologic events represent these kind of threats?

<John> Well, there are a number of answers to that. One, we have to live somewhere, and it's probably the exception rather than the rule that there's a place on this planet that doesn't have some kind of potential geological threat. Secondly, we tend to be attracted to areas where there can be agricultural or economic benefits, and you have this trade off between the threat on the one hand and the benefit on the other, and increasingly so in modern times, we have a population problem that as the population expands certain groups tend to more and more attempt to inhabit or live in areas that are rather marginal in terms of human conditions, and so they may be accustomed to one form of life which really doesn't work too well where they are. Examples are, for example, Bangladesh, in the Alluvial Plains or along the edge of the Sahara Desert, and so you find yourself just pushed into that kind of a position.

<Rick> That's true; yet let's see if there's something else, too that if you live in a particular region where there's a hazard, and your ancestors and there's an ethnic sense of that place, maybe at the time when that ethnic sense was developed, that place wasn't a place where there were hazards; flooding, specifically.

<John> Yes. Yes.

<Rick> for example, that's not probably so true of volcanoes and earthquakes, but certainly flooding and mass movements. An area might have been quite habitable at one time, and now because of desertification or because of changes in climate, that area might not be habitable.

<John> Yes, or the attitude has shifted; in other words, you've lost that ancient sense of the land that their ancestors had.

<Rick> Yeah, well, the other thing that's relative here, I think, is that "disaster", the word is a human word; there's no such thing as a "natural" disaster, right? A disaster is only a disaster because we define it because it affects our lives, so

<John> Yeah, well, I agree. It's not just the word. The whole concept of a disaster is human created. You start off with a hazard; the hazard you have little or no control over, but how you are inhabiting or occupying the land or where you are is going to say a lot to whether you are prepositioning yourself to make a bad problem into a disaster, and so, you know, if you don't

<Rick> Well, a good example is would there be an earthquake hazard in San Francisco if there were hunter gatherers occupying

<John> Yeah, that's a perfect example. Obviously for 20,000, 40,000 years you had hunter gatherers on the area of San Francisco, and they had no earthquake problem.

<Rick> Right.

<John> But now you have the Nimitz Highway out there, freeway collapsing.

<Rick> Right. There's another thing that we might mention here, too, is that if we read the newspapers, it seems that there are more earthquakes now then there used to be.

<John> Yes.

<Rick> So are there more earthquakes because there are more earthquakes, or are there more earthquakes because there are more sensitive instruments, or are there more earthquakes because the press has picked up on it and reports more earthquakes.

<John> it's more like you have more population, and so the press eye is addressed there, and so suddenly people are surprised that a place like California has, you know, earthquake problems, but the rate of earthquakes seems from the geological record to be pretty much the same rate of what you have right now.

<Rick> Certainly episodic, but not--The reason I mention is this is I think we'll come back to this when we look at attitudes about disasters, and there certainly is a psychological aspect to disasters.

<John> Yes.

<Rick> And planning for disasters. It's also interesting to note here that because the Earth is so complicated that these various processes that interact: The plate movements interacting with climate systems are going to produce events of varying magnitudes. One of the people mentioned in the lesson on streams, the video on streams, that there's always a larger event that's going to occur than any of us have heard previously; in other words, however big an earthquake or however big a flood there's been at one time, there's always the potential of having a larger one, but obviously the larger the event, the longer the time

<John> Right.

<Rick> between those events, so these are parts of long natural cycles, so it's highly possible that there would have been, there is a region that's not experienced any type of hazard during the recorded history of man.

<John> Yes. Yes.

<Rick> But it's sitting there waiting as a potential which we haven't identified yet.

<John> Yes, yes, or you even have the way people go and move into river valley areas to where there are attempts at channelizing and so on, Actually postpone an event, so that when it does come about later, it comes by as a real disaster.

<Rick> Yeah, so it's not only how we use the land, but it's how we try to modify the land, which may mitigate a disaster now but may force the big one, like what you said, a flood of the stream channel which is effective now, when the 200 year flood comes may be worse than it would have been had the channel not been there. Well, the other thing to note about this, I think, is that geologic events will occur in a particular place regardless of whether or not our structures and lives are affected, right?

<John> Exactly. Yeah.

<Rick> So that it's again the idea is they're not hazards in the sense that if there's no people there.

<John> Yeah, the event's happening whether you're there or not. It's a human perception that is projected on top of it.

<Rick> Right.

<John> And as we've mentioned, earlier peopled had no such problems with this because they lived lives or organized themselves in such a way that it didn't build up into a problem.

<Rick> The other way to look at this is if you don't know that an area is a hazard, then you can't have this perception of "hazard."

<John> Yes.

<Rick> See what I'm saying

<John> Yes.

<Rick> I think, this will be addressed, I think, in the video. Today's video is about a particular disaster in Northern California, the Loma Prieta Earthquake, sometimes called the "World Series Earthquake of 1989," and I think what we ought to do is look at how this documents the research that's being done and the attempts of prediction, and then afterwards come back and continue this discussion. So let's do that. Let's watch the video.

Music

This is San Francisco, the City by the Bay, an alluring location not only to the 800,000 who live here, but to millions of others who have ridden cable cars up and down its hilly streets, crossed over its spectacular bridges, and been charmed by its unique combination of enticing qualities. Apart from its many other attributes, the San Francisco Bay area boasts two Major League baseball teams, the "San Francisco Giants" and the "Oakland Athletics."

Late on the afternoon of October 17, 1989, the Giant and the As prepared to do battle in the third game of their crosstown world series matchup. Some 90 kilometers to the south, another battle is about to played out by two underground titans known as the "North American and the Pacific plates." A section of the San Andreas Fault that marks the boundary between these tectonic plates has been locked in kind of a stalemated tug of war since 1906. In a matter of moments, that great standoff will come to an abrupt end. In the process reducing America's favorite pastime to little more than a trifling footnote, but for the thousands of fans packed into Candlestick Park on this October afternoon and for the millions watching the fall classic at home on television, there's no indication of any imminent danger.

Until four minutes after 5 o'clock Pacific Daylight Time. <screams and sirens> In large part because of the World Series, television crews blanket the entire San Francisco region, and only minutes after a powerful earthquake has ripped through the Bay area the first images of horror begin to emerge. In the frantic minutes that follow the quake, few geologic details are known. What is rapidly becoming clear, however, is that a disaster of enormous proportions has occurred. Go home! We've got serious problems obviously! Go home and secure your residents. Shut off the gas. Shut off electricity! Store water! Prepare for aftershocks! Prepare for three days of those services! You got 90 minutes of light left! You better make use of your time!

As fire and paramedic units rushed to provide assistance to quake victims, scientists of the United States Geological Survey in Menlo Park, California hastily convene to begin analyzing the quake as well as to dispense information to the media and the general public.

The quake's magnitude is pegged at 7.1 on the Richter Scale, meaning this has been a powerful earthquake capable of causing serious damage to both people and property. Most of the world's attention remains focused on damage in and around San Francisco, such as here on the Nimitz Freeway where it feared that scored of motorists have died, and here the posh Marina District where prized real estate has been twisted into grotesque shapes, but apart from select localized areas that have been severely damaged, most of San Francisco has come through the quake in relatively good condition.

There are problems of course. Delays in both transportation and communication are widespread, but the city is still functioning. Unfortunately, the situation some distance to the south is less encouraging. The quake's epicenter is located near a peak in the Santa Cruz Mountains called "Loma Prieta," and it is communities closest to Loma Prieta like Santa Cruz, Watsonville, and Los Gatos that have actually been hit the hardest.

There is the house down the hill; what's left of it, shall we say. Harry and I were in the dining room, each of us attending to our little chores there, phoning, and when we felt it, so we knew right away to go to the doorway, the traditional earthquake movement and wait for it to subside. Well, it didn't, and then we continued on down the hallway to the front door behind me, and we were thrown to the floor, and I ended up on the floor in another doorway when I finally stopped.

Only one person was in the house, and that was one of my tenants. She was up that little alcove up there, that nook where the windows are, and her roommate had just come down here to unload something from the car when it hit, and she could look up and see her roommate just kind of swaying with the house, and meanwhile the porch is falling down, and the house slipped off the foundation, and she was screaming, and it was horrifying.

Within minutes after the quake hits, relief efforts are underway. The official relief apparatus includes various groups of agencies from all levels of government. Their immediate goal is to provide assistance, especially food, shelter, and medical attention wherever it is needed. In the face of tremendous devastation, local, state and federal officials respond as quickly as they can.

Still, there is a sense of frustration shared by nearly everyone associated with the relief operation. You know, you'd like to go in there and feel like you could, you know, move the concrete, get the vehicles out, do what you can in your rescue efforts anyway, but if you look at the structure and see the magnitude of the problem, you sit back for a moment, and you realize that it's not going to be resolved immediately.

While the official response is well coordinated, there's clearly too much damage for public agencies alone to adequately address. Fortunately, as often happens in the face of natural disaster, there is an outpouring of support from private citizens. Relief organizations like the Red Cross help galvanize this sentiment into action, and a strong volunteer effort stretching from Santa Cruz to San Francisco quickly takes shape.

The young people were just wonderful how they helped us. People we never knew, and they never knew us, but they carried us in their arms down the stairs, and they didn't leave us one minute. As relief efforts continue, geologists comb the surface area around Loma Prieta collecting data which will help them better understand this earthquake. Ironically, the efficiency of the repair crews poses something of a threat to the work of investigating geologists.

The cities, and counties, and state governments are very efficient at fixing things, so for example, damage to roads and public structures are fixed very quickly, so that you lose part of the data if you don't get out there and record it as soon as possible.

Another major obstacle facing the teams of investigators is weather. Both wind and rain can wipe out vital evidence following earthquakes. Apart from weather and crop repair operations, the U. S. Geological Survey is faced to deal with one additional problem, damage to its own facilities. Loma Prieta disrupted our network operations for several hours here in the office. We lost power as did most of the community for about six hours. We have emergency generators, and we were able to run our central computers and the tape recorders on those generators. Many computers that were empowered by the emergency power were down, and many functions that we would have wanted to perform were impossible.

But despite some problems with its equipment, the USGS continues to operate effectively. For example, the steps that were taken to ensure that the seismic monitoring network stayed alive worked well. We really did not lose any down time from the earthquake, and we were able to essentially provide continuous information to the public and to local and state officials about what was happening during the earthquake.

Really, the most important information to relay to the public after an earthquake is the fact that aftershocks are expected to occur and the question of how long we expect them to occur, and what kind of additional hazard they represent.

During the Loma Prieta Earthquake sequence, we were able to speak to the public every day and remind everyone that aftershocks are likely to occur, and although we can't predict the time of the aftershock, the first week or two is the most dangerous time, and aftershocks can continue for several months after the main shock. As research efforts continue, geologists begin to recognize that there are a number of surprising aspects this quake.

One of the interesting things about the Loma Prieta Earthquake was that the fault that broke was not the vertical strike fault that we tend to think of as characterizing the San Andreas Fault. Geologists normally expect the two sides of the San Andreas Fault to slip past each other horizontally with the west side moving to the northwest. This did, in fact happen, but the west side also moved vertically riding up on the eastside between one and two meters. What also catches the attention of geologists is that the focus of the quake occurred 18 kilometers beneath the surface surprisingly deep for California earthquakes.

Perhaps because the quake was so deepseated, no rupture broke the surface along the fault, but numerous fissures resulted form landslides triggered by the shaking. The earthquake was also surprisingly brief given its great power with shaking felt for only about eight seconds. The extent of the damage in parts of San Francisco in Oakland, a full 90 kilometers from the epicenter, also surprises most people, and yet the event itself was hardly a surprise.

Earthquakes along the San Andreas Fault have no doubt occurred throughout its 30 million year history. Whenever the plates on either side of the fault lock and strain against one another, a breaking point is eventually reached, and as the plates lurch past one another, an earthquake occurs, but there's another reason why this particular quake was not unexpected.

Scientists have known for several years that the 1,200 kilometer long San Andreas Fault is actually composed of individual discrete segments. Geophysicists have calculated the probability of major earthquakes in each of these regions along with the maximum likely magnitude at each location. The Loma Prieta Earthquake occurred along one of the six fault segments considered most like to sustain a magnitude 6.5 or larger event within the 30 year interval between 1988 and 2018.

Once the shaking stopped, many people almost felt a sense of relief assuming that they would no longer have to worry about another major earthquake during the foreseeable future; however, the Loma Prieta Earthquake was not the so-called "big one" that geologists and millions of Californians have been waiting for.

We know that there will be future larger earthquakes in the Bay area probably within the next few decades, and there much likely to be closer to the centers of population and to shake those centers of populations more strongly than Loma Prieta, and actually the long shaking should last longer. As terrifying as this tremor was, geologists call it a "moderate" rather than a "great" earthquake.

The magnitude of the 1906 quake which also shook the San Francisco Bay region has been estimated at 8.3 meaning it released about 60 times more energy than the Loma Prieta quake; nonetheless, there is a chilling irony that links the two events. When California staged an international exposition in 1915, the City of San Francisco wanted to divert world attention from the devastating quake that had rocked the area nine years earlier.

In so doing, it hoped to market itself as a viable Pacific port. This led to the building of exposition structures in the Marina district. The materials selected to fill in the shallow water of the marina were a combination of rubble from the 1906 quake, and uncompacted mud and sand. Seventy-four years later, this community built atop the rubble of one earthquake would suffer catastrophe from another.

Those very soft surface deposits shook very violently, and, in fact, they failed. You had what we call a "liquefaction" where the ground simply loses the ability to support loads, and so that buildings that are sitting on that material sunk into the ground and shifted. the foundations of the building shifted, and the reason for that is that because as the earthquake wave moved away from the epicenter, when it hit this geology, this loose unconsolidated soil, the ground motion actually was amplified or increased five times what it was maybe a mile up on solid bedrock up here, so geologists have understood in the last ten years where to build.

Not only where to build, but how to build, and we have maps showing where areas of loosely consolidated ground, and this is one of them here, and if we look all around the edge of the San Francisco Bay: downtown, the Embarcadero, the Embarcadero Freeway, south of Market. These are small packets of liquefiable soils, and these are where we have the most documented damage in the entire San Francisco area.

The fact that geologists and many public officials have known for some time which areas are most vulnerable to earthquakes is of little comfort to those whose lives have been devastated by this disaster, but as the focus shifts from the horror of Loma Prieta to the inevitability of future quakes, the race to increase our knowledge and somehow prepare for this seismic giants intensifies. The approach that generally attracts the most attention, and yet continues to be the most elusive is "earthquake prediction."

Scientists are studying everything from magnetic fields to groundwater levels and deformation of the Earth's crust. In an effort to come up with a formula that can accurately predict earthquakes, while some promising work has been done, a definite earthquake prediction technique has yet to be developed. The Loma Prieta quake, however, has contributed what may be an important clue to the prediction riddle. At Stanford University, Physicist Anthony Frasier Smith studies low frequency electromagnetic waves. In part to avoid extraneous signals from the San Francisco area, Frasier Smith looks south to the Santa Cruz Mountains to find a suitable location in which to place his research equipment. What he didn't realize was that the spot he chose would turn out to be directly at the epicenter of the Loma Prieta Earthquake.

Our first thought after the Loma Prieta Earthquake was that we'd probably never see our equipment again because there was a lot of damage all over that area. Power had been lost. Communication had been lost, and telephone lines were down. We just didn't know what had happened down there. Remarkably, Frasier Smith's equipment survived in tact, and when one of his colleagues checked out the data that had been reported just prior to the quake, he found something unexpected and quite extraordinary.

There were very big signals coming through, and the thing that most excited him was a big increase about three hours before the earthquake where the signals had grown so large that the computer that runs our system was putting out warning messages saying that these signals were now so large that we no longer could trust the data. The measurements were actually smaller than the real signals were. They were no longer capable of following the real signals. What is intriguing about these fluctuations in the electromagnetic signals is that they may have been related to the Loma Prieta Earthquake.

Frasier Smith is quick to point out, however, that it's too early to claim that they can definitely be considered earthquake precursors. While it's uncertain whether Frasier Smith's research will lead to an effective method of earthquake prediction, there's no doubt that something needs to be done to minimize the level of destruction that large quakes cause.

Of particular concern are earthquakes that occur along faults situated close to major population centers, for example, the Hayward Fault, which lies just east of San Francisco Bay. If an earthquake of the same magnitude as the Loma Prieta quake were to occur on the Hayward Fault, a population 15 times larger would be at risk. Engineers at the University of California at Berkeley contend that rapid unchecked growth in such areas reflects a dangerous lack of playing.

The Hayward Fault would run exactly along the freeway. The freeway run along the Fault, and then there are most of the hospitals that are along there. There is a Navy Hospital, and many schools are there. This is what I mean the lack of disaster prevention policy. These buildings should know people there. These highways should people there. And yet hospitals, schools, and highways have been built in the vicinity of dangerous faults.

Clearly, the prospect of tearing these structures down and relocating the millions of people who utilize them is not feasible. The most practical alternative seems to be retrofitting existing structures, so that they will be more likely to survive a major earthquake. Most casualties associated with earthquakes are caused not by the quakes themselves, but by the failure of buildings, bridges, and other structures. This is one of the most serious problems of the government, what to do with buildings or with structures that we know that are built on soil that will suffer damage. At the moment anything that we will do there will be very expensive. It's a very expensive operation. It can be done; however, it will require a tremendous economic effort.

There is yet another strategy for minimizing the impact of earthquakes. A seismic early warning system still in the experimental stage that was installed following the Loma Prieta earthquake. With this system, the instant a large earthquake is recorded sensors in the ground transmit a signal to receiving stations throughout the area. You're taking advantage of the idea that once an earthquake occurs and it's detected, you can essentially outrace the seismic waves that are propagating through the ground by sending a radio signal ahead, and so the farther away you are, the more time of warning that you have. The actual time saved by such a system might only amount to 10 or 20 seconds, but this could be long enough to divert or temporarily immobilize public transportation systems or to simply warn people to take cover and possibly save their lives.

So I think it has some possibilities, and the state and local officials are evaluating how such a system might best be used in future earthquakes. For the residents of the San Francisco Bay region, the impact of the Loma Prieta Earthquake was enormous. Sixty-three people lost their lives, and another 3,800 were injured. More than 28,000 homes and businesses were damaged, and the overall financial cost was about $6 billion.

Still, the results were far less catastrophic than they might have been. Had the World Series not been in progress, more people would probably have been on the Nimitz Freeway when it collapsed, and if the quake had occurred closer to a densely populated area, the death toll could have been in the thousands. While earthquake prediction may never become a practical tool, we can use what we know about earthquakes to limit their impact on our lives; for example, we can avoid building in areas where the ground will rupture or subside during a quake and in areas where liquification is likely to occur.

We can design new buildings and homes to withstand the shaking of earthquakes. Old buildings can be reinforced or turned down. The contents of all structures should be secured to avoid the injuries caused by toppling furniture and falling objects. We can also prepare for earthquakes by storing emergency supplies at home, in our cars, and at work and by arranging for earthquake plans with our friends, our families and co-workers, and, finally, we can require our elected representatives to create a comprehensive earthquake policy to strengthen building codes and public structure.

Such a policy would employ the best current technology to ensure that highways, bridges, and dams are able to withstand the earthquakes that we know will come. We understand why earthquakes happen. We can sometimes forecast the general location of the epicenter, the intensity of shaking, and even where the Earth will rupture and subside, but knowledge alone isn't enough. We must have the collective will to apply this knowledge and to finance the changes we know must be made. Only then can we make our world, if not earthquake proof, at least relatively earthquake safe.

Music

Major funding for "Earth Revealed" was provided by the Annenberg C.P.B. Project.

Well, that video certainly does show us a lot about the Loma Prieta Earthquake, and it gives us a pretty good sense, I think, of what measures are being taken to try to predict these things, but it certainly does raise a lot of questions, I think, the video didn't deal with.

<John> Yeah. Yeah. A lot.

<Rick> One of the things. My note here. We have certain of expectations about the behavior of the Earth, right. We expect things to be regular. Why do we insist on expecting this regularity, when we know that variability is the norm, and there are certain things that are regular, right? The sun and the planets, but most things aren't.

<John> Well, I think it leads to a real question as two different ideas, one of something being periodic, such as the moon, the phases of the moon, the sun coming up every day. The other, seasons. Seasons are a very good example of periodicity, so we have an expectation, and we can make some reasonable predictions, but there's this other aspect of "episodic" meaning that you are going to expect certain changes, but it's not necessarily a regular form of periodicity.

<Rick> Well, we've seen that already, I mean, in the lesson on "Evolution." We noted, for example, that evolution takes place in punctuated equilibrium in response to changes. Geologic processes happen in punctuated equilibrium, so isn't it funny that it's only these astronomical stellar processes that tend to take place in regular cycles, but yet we somehow project this and expect this to happen for all kinds of, I don't think we really expect it to happen so much as we wish it would happen.

<John> Yeah, well, of course, science in the modern sense started with the observation of these very predictable events, such as planets going around the sun and so on, and there was a real celebration of being able to have that kind of predictive ability, and then in its application in the modern world, engineering technology; of course, we have to develop things that are going to be very, very predictable, so we get into a kind of controlling mind set, and, therefore, as you said, that we're projecting onto a world.

<Rick> It's interesting you should mention that because you mentioned this in terms of the development of science and how important it was, but when those developments were taking place, they were done to be more in tune with nature, not to be removed from it.

<John> Yeah.

<Rick> I mean the whole idea was crop cycles and when do you plant to make sure the growing season is right and rely upon the flood of the Nile and this sort of thing, so it was more to be intune with rather than to be separate from, and we've somehow distorted that from this idea of separation.

<John> And it's interesting because this is a fairly recent event, the last few hundred years. I mean you go back and you look at the poetry of someone like William Blake, who said "to see the world in a grain of sand" and "heaven in a wildflower." "Hold eternity in the palm of your hand" and "infinity in an hour."

<Rick> That's right.

<John> And yet we discover now that this is more of a celebration in looking back at this thrust of power of the energy, and we have to get beyond that because it has resulted us in having this separation, our everyday lives from nature.

<Rick> Very much so. Well, one of the statements, and I think it was the program on "Streams" was by, I think it was D. Trent, one of the guys in the video said that anyone who is surprised by flooding is not paying attention.

<John> Yeah.

<Rick> And he was using this in the sense that we tend to look at a stream and artificially believe that the stream somehow consists just of the water; whereas, the stream itself is actually a dynamic system, which includes the sediments. I think the line was that the flood plane of the stream is those sediments which the stream is not using at the moment.

<John> Yeah.

<Rick> So doesn't this kind of address this idea?

<John> It does. You know, the modern of pathology of sorts that we have here is that we have substituted the balanced approach of "inhabiting" the land, and instead what we tend to be doing is "occupying" the land, and as an occupier, you're not very much in tune with the local environment, are you? You think of an occupying army comes in there. The last thing they're going to do is listen to the local folks. They're trying to tell rather than to listen, and that's what happens. You think that somebody that goes into an alluvial valley. He's attracted there because the land is fertile. He can did deep into it. Why? Because the land was placed down from thousands and thousands of floods that have come through floor. He digs his basement and everything else, and then he's so surprised that a flood came by.

<Rick> It's interesting because it's exactly those qualities of the alluvial plane that make them suitable that also make them disastrous.

<John> Yes.

<Rick> Because the alluvial plane wouldn't be there without this periodic, episodic maybe is the better word, flooding of the flood plane. Well, see, it's different, though, because the stream at least has this episodic nature, and we know that there are going to be floods, and in some sense we can even predict those floods, but some events seem to have no periodicity at all. At least in flooding, for example, the Nile has very regular annual floods. The exact size, and the exact day, and the exact day isn't always predictable, but other events like earthquakes, and volcanic eruptions, and mass wasting are much less periodic and much more episodic, and have a much larger time span between the episodes, and I mean a volcano may erupt only once every 2 million years, and so there may be volcanoes that weren't even around that hadn't erupted since humans inhabited the Earth in the first place.

<John> Yes.

<Rick> So it's kind of a little different there. Well, you know, so we do learn to expect these disastrous events at the same time pretending that they won't happen, but we never know exactly when they'll happen or the exact magnitude of the event, right? So we can say that there's likely to be an earthquake of magnitude eight and a half in Southern California in the next 30 years, okay? But in continuing studying these things, what kind of information can we get from geological studies even if we can't say the exact time of things.

<John> Well, you can first off be reassured pretty much that indeed the event is going to happen.

<Rick> Yeah.

<John> You've gone out there and you see that there is this long pattern. You basically understand the mechanism of continental plates sliding along one another. Certainly you can go out and prove that the continental plates are there, and they're sliding alone one another. You're therefore able to say that indeed we will have another earthquake. You may get some sense of how often in a very rough way this is going to happen by being able to find evidence in the geological formations going back thousands of years, so you come up with an approximate average. Let's say it's once every 100 years, maybe plus or minus 50 years or so.

<Rick> Big variation there. Well, that's basically what they've done with the Loma Prieta thing. I mean they go along, and they look at fault traces, and they try to do age correlations, and they try to get an average annual estimate, but we know that those estimates are, as you say, a hundred years plus or minus 50. Well, you know, we know for example that there are certain regions like, you're not likely to find a volcanic eruption occurring in Kansas, okay?

<John> Tornado, maybe.

<Rick> Tornado, yes, but then you don't find many tornadoes in Northern Washington State.

<John> Right.

<Rick> So there are sort of these regions, but there's another question, I think, that's even more important here, something the video didn't mention at all. Where you spend all this time, and money, and resources trying to predict disasters like we've been talking about. Is it always a good idea to predict disasters? I mean first of all, does it work? And secondly, is it a good idea in the first place?

<John> Well, there's a considerable problem associated with that. Let's take a look at, there's an article that was written quite a number of years ago about1967 by Garrett Hardin, and, in fact, he points out it took him two years to even get it published because no one wanted to talk about it. In this article he asked the question whether or not it is in our best benefit to predict earthquakes. Now, surely on the surface you think "Of course, we want to predict an earthquake," and yet he makes a very strong case to say that-- Consider the following: We're all aware of very recently of Hurricane Iniki having hit Kauai, but what happened when the process of Hurricane Iniki hitting Kauai. We go for years; in fact, it was a ten year period in which we lived our everyday lives in which our economy, our society, and so on is not tremendously disrupted. Then we get a 48, actually in this case it was less than 24 hour's notice that we're going to have the hurricane, so there's a shift here, a very interesting shift in the psychology in the society.

<Rick> A shift in behavior.

<John> Yeah, we suddenly turn our entire undivided attention to the hurricane. No question about that. You're crazy if you haven't. So what do we do? We start gathering up food that is going to survive when we don't have electricity, canned goods, bottled water, get cooking supplies, take care of other things, batten down the hatches, so to speak. We, at least go through the efforts as a community. There's a lot of cooperation. There's a lot of, there's a real shift, almost an exhilaration that's involved in it. Then, the event comes.

Okay, so we've had a chance to prepare for the event. Whether it really is physically better or not is an open question, but we prepare for the event, we survive the event, and then we turn around, we assess what's going on, and we start to rebuilt our lives, and continue on.

<Rick> And may I add here that if the event was not significant as it wasn't here on most parts of Oahu, we quickly forget that the thing's past.

<John> Yes. Yes.

<Rick> The community spirit disappears, and all of a sudden here's Kauai over here with, you know, still with people without any houses and electricity, and our life goes on, and we don't really

<John> That's a very good contrast of Oahu, most of Oahu, and versus Kauai. I have friends that just came back from Kauai. Now, contrast this to something like an earthquake. Now the video showed the possibility of maybe being able to get a prediction out a matter of seconds before it hits.

<Rick> Twenty seconds, I think.

<Rock> All right, you know, 20 seconds, all right. That's a rather minimal help. The question that Harden asked was let's assume that we did develop the technology to be able to predict an earthquake in advance, how helpful to the society really and truly would this be? In the case of something like the hurricane, we get a warning, let's say 48 hours in advance, something like a 50 percent certainty that a hurricane of a certain strength may hit you.

<Rick> Right.

<John> Okay, in the case of the earthquake we could be talking about "Oh, five years from now on such and such a date, plus or minus a couple of days maybe, we're going to go ahead, and we're going to have this massive earthquake.

<Rick> So he was talking about giving long term warnings of the earthquake.

<John> Right, which is after all what people keep trying to talk about.

<Rick> You would think so, yeah. You would think. I mean, on the surface it seems like the more warning you have, the better off you'd be, and the more chance you'd have to prepare for it, but

<John> Right, but this is what he points out is that this isn't necessarily such a good idea assuming that you could even do it because he says "Ask yourself the question if you were thinking about buying a house in that area, would you buy the house? Or would you be sort of like waiting until you saw how everything shook out and knew then that there was some longer period before the next earthquake before you went and did it. Now, what do you end up with? Well, you end up with the economy starting to stagnate out, if not downright collapse. You're going to find, for example, that life goes on, and so what's going to happen is that people are going to be coming along, and they're going to still be selling houses. They're going to sell houses because people are relocated. They may be selling houses because they've decided that they don't want to live through this earthquake, and they're going to get out of there. There are going to be houses that are going to be sold because they're going to be closing out estates when people pass away.

<Rick> Can I interject here?

<John> Yeah.

<Rick> Do you think the houses would really be sold, or do you think that they'd be put on the market?

<John> They'd be put on the market.

<Rick> That's a good distinction there.

<John> Yes, right, so now what's going to happen here is that you're going to have what I guess what has been called recently a "supply side economic situation" in which you have lots of supply, but you're not going to have much demand. Who's going to want to buy it except speculators?

<Rick> Right.

<John> You know, and so everything is now going to be really falling into the hands of the speculator, falling into the hands of the gambler, and the economy will start to collapse.

<Rick> Well that's very true. That's a really good point, and Harden, I think in the article, well, Harden, you know, is sort of a, he likes jabbing the society in the side

<John> Yes.

<Rick>with these arguments, but what about the aspect of the psychological part of this?

<John> Oh, yes.

<Rick> Because think of, you just mentioned that during, you know, the 24 hour warning that we had for Hurricane Iniki how the behavior changes.

<John> Yes.

<Rick> Imagine living under this stress of knowing for sure that 8:00 on July 30, 1993 there will be a magnitude 8.5 earthquake.

<John> Yes. Yes.

<Rick> What's the response to that.

<John> Well, oh, that's fascinating because now in the past when we talked about the hurricane, you had what? You lived with the hurricane for 48 hours?

<Rick> Um-hmm.

<John> And it was gone, and you, okay, you had leftovers and problems, and you have to rebuild, but in terms of the intensity of the uncertainty, okay, you had only 48 hours or so of uncertainty, but now maybe we're talking about maybe five, six years of uncertainty?

<Rick> So it sort of comes down. What's better? Is it better to have a really short intense period of uncertainty? Or is it better to have a relatively protracted period of, you know, less stressful uncertainty. I mean, how do you weight those things?

<John> Well, I would tend to argue that it's better to have that short period of uncertainty, and in that short period of uncertainty, you have a sense of community bonding, which helps you get through a lot of this sort of a thing. The case of if you were able to predict an earthquake, you're going to have years and years of uncertainty; in fact, uncertainty will become the lifestyle, and one of the things Harden pointed out, and this back in 1967, and there have been plenty of similar experiments done since then, is that he pointed out where you have two monkeys, and these two monkeys are given periodic electric shocks, so they can anticipate when they're going to get an electric shock. Now what they did was the two monkeys given the identical electric shocks, identical environment, one monkey was given a button, and the monkey learned to push the button, and what would happen is he would not get the electric shock, or it would reduce his electric shock.

<Rick> When he pushed the button, so he could control the shock that he got.

<John> Yeah, he had the sense that he could control it. All right, so what happened? Which monkey do you think ended up with the ulcers.

<Rick> I think I'd rather not have the switch myself.

<John> Yeah.

<Rick> Yeah.

<John> Well, the monkey, invariably, the monkey who had button was the one that ended up with the ulcers, so you're talking about considerable pressure on society.

<Rick> Well, it sounds like considerable pressure, but it certainly, I mean we have enough problems in society anyway without having this pathos of anticipation and stress being the dominant factor in a particular area. Among other things, that's not the only thing, but, of course, these problems are only a small subset of all these predictions. I mean there's other things that go into this other than just the economic factors.

<John> Definitely.

<Rick> I mean just specific to the real estate, but it's also interesting that his insights were valid for other disasters as well.

<John> Oh, absolutely.

<Rick> He specifically focuses on earthquakes because of the nature of earthquakes being such that we can basically talk about a window, and, like you say, we have much better predictions of hurricanes because we have Hurricanes give more warning, right? I mean we have weather maps, and you see the hurricane coming, and it either is coming this way or it isn't.

<John> Well, you have that period of time at least for the psychological adjustment that it's coming, right.

<Rick> So earthquakes are a little bit different in that aspect. I think Harden even points this out that it's probably unlikely that we will ever be able to actually pinpoint the time of an earthquake.

<John> Right.

<Rick> But that makes it even worse, doesn't it in a way?

<John> Well, I think not, really. I think it's a blessing in a certain way because as we just said, you know, if you could pinpoint it, you're going to run into the problem of all that anticipation, so it's a relative thing in terms of the amount of advance time.

<Rick> Well, we're running out of time here, but I want to make one note here, and maybe

<John> Sure.

<Rick> we'll have time to discuss this in the next lesson that we do have the ability to forecast the ultimate disaster.

<John> Yes.

<Rick> And that is the total degradation of our planetary environment; yet we're reluctant to take the steps that might prevent it in the first place, so let's keep this in mind as something to come back to in the next lesson, so, well, that's it, I think, for this time. Thanks, John.

<John> Sure.

<Rick> Let's do this the next program.

<John> Oh, definitely it will be interesting.

<Rick> So next time we'll take a look at geological resources and our use of them, as well as our attitudes about the resources and the effects of them. This will be the final lesson. It's Lesson 26 in the study guide and Chapter 21 in the textbook. We'll look at uses of resources and pollution and their long term effects, as well as our attitudes about specifically not the planet but our attitudes, our attitudes about our relationship with the planet, so I hope you'll join us for this final program, and I'll see you next time.