I Successfully Predicted Four Earthquakes This Week! And Why Events in Italy Today are Chilling

Before anyone gets excited about today's headline, read the following disclaimer:

NOBODY CAN PREDICT EARTHQUAKES IN THE SHORT TERM THAT IS IN ANY WAY  USEFUL FOR PROTECTING LIVES AND PROPERTY!

Allow me to repeat myself...

NOBODY CAN PREDICT EARTHQUAKES IN THE SHORT TERM THAT IS IN ANY WAY  USEFUL FOR PROTECTING LIVES AND PROPERTY!

Now...let's read this together out loud in unison...

"NOBODY CAN PREDICT EARTHQUAKES IN THE SHORT TERM THAT IS IN ANY WAY  USEFUL FOR PROTECTING LIVES AND PROPERTY!"

Good. Let's move on...

Last week was Earth Science Week, and on Thursday we in California did emergency drills for earthquakes in the Great Shakeout. In conjunction with the Shakeout, I revised a previous post about the myths and misconceptions about California and earthquakes. It was quite long, so you may have missed that I predicted a couple of earthquakes in one of the later paragraphs. They were as follows:

• 200 earthquakes will occur in California,
• Of these, there will be a magnitude 4 quake in southern California, most likely in the Colorado Desert near Salton Sea.
• There will be a magnitude 3 earthquake in northern California, most likely north of the Bay Area, somewhere around Clear Lake.
• There will be a larger quake at the Vanuatu Islands in the Pacific Ocean, quite possibly in the magnitude 6 range.
• There will be a magnitude 5 earthquake offshore of Japan.

So, how did I do?

Source: http://earthquake.usgs.gov/earthquakes/recenteqscanv/

• There were 448 earthquakes in the last week in California.
• There was a 4.2 magnitude quake in Baja California, just over the border from the Salton Sea
• There was a 2.7 magnitude quake near Clear Lake, and a 3.6 magnitude quake a bit farther north near Arcata.
• There was a magnitude 6.2 quake near the Vanuatu Islands in the Pacific Ocean.
• And finally, there was a 4.8 magnitude quake near Japan.

How about that? Five for five. 100%. So I am an earthquake predictor par excellence, eh? No. Not at all. I did what any charlatan or fake psychic (and they're all fake) would do: I played the odds. Take a bit of geologic knowledge and set the parameters wide enough, and you will almost never get an earthquake "prediction" wrong. Earthquakes happen in particular regions, and the "background" seismicity will always include some slightly larger temblors.  "Psychics" have been predicting quakes for years to pad their scores on the yearly list of predictions for the new year. They are depending on getting enough easy predictions right so they sound like they have those "special powers" even though they get practically everything else wrong.

Here's what's wrong with this...they act with impunity, knowing they will never pay a price for being wrong. They will scare people without fear of arrest for causing worry and panic.

So what was the chilling news out of Italy today? It was this: six geologists were convicted of manslaughter for failing to predict a terrible quake that killed 309 people. They were scientists who were convicted for not foreseeing the unforeseeable.

This is a huge issue. Self-styled psychics and con artists can act with impunity without fear of punishment, while responsible seismologists and other scientists are put on trial for not being able to predict something that has never been successfully predicted. Something is very, very wrong in Italy, and I hope the geologists are cleared on appeal.

People who are caught in tragedies will always need some way of understanding what has happened to them. They will often turn to a scapegoat as a way of avoiding tragedy in the future. In ancient Israel, a goat (a "scapegoat") was symbolically loaded with the sins of the people and banished to the wilderness. In the culture of the day, when the gods ruled the heavens and controlled the natural disasters that affected society, it almost made sense to do this. In this modern era, it makes no sense at all to make scapegoats out of the scientists who are doing all they can to protect lives by understanding the patterns and probabilities of earthquakes.

We can't make short-term predictions, but we can certainly make long-term ones. This is a map of the probabilities of damaging earthquakes in California over the next 30 years. Should we arrest the geologists if a quake on this map turns out to be bigger than predicted?

Tragic Quake in Italy: a peripheral note

Tragedy this week in L'Aquila, Italy, when a 6.3 magnitude quake collapsed buildings and killed 235 people (at last report). Many in the geoblogosphere have commented about the tectonics of the quake (check here for the latest posts), and the seemingly odd juxtaposition of extensional quakes in an ostensibly compressional landscape associated with convergent boundaries.

I don't have much to add to the discussion, but I did want to share a few photos of another town in the Appennines in central Italy where the quake occurred. Gubbio is small medieval village tucked along the mountain flanks of the fault systems that slice northwest across the region. The valley is a prominent fault graben and provides a vivid example of the appearance of the many fault zones in the region.

In Roman times, the inhabitants of the region felt secure enough to live out on the valley plain, under the protection of the Roman Empire. When the empire crumbled, the cities became isolated and vulnerable to attack, so they moved the towns to a more defensible position at the base of the steep mountains. Walls and buildings were robustly constructed out of thick walls of mortar and rock. Unfortunately, little thought was given to the possibility of earthquakes, and many of the buildings (as we saw this week) are seismic death traps.

When a valley sinks along a fault system, a mountain block rises in a relative sense, forming a prominent ridge. Erosion produces deep gorges, and the original fault surface (the scarp) is shaped into a series of triangular facets , separated by wineglass canyons: alluvial fan (base of glass), deep mouth of gorge (the stem of the glass), and the open canyon above (the cup). These features are visible in the photos above. Unfortunately, Gubbio is threatened by the same kind of earthquake activity.

The top photo shows the triangular facet that forms the backdrop of Gubbio, while the second reveals part of the wineglass canyon formed by the erosion of the Bottaccioni Gorge. The pictures are a record of one of the great geologic days of my life: a visit to the Gubbio exposure of the clay layer where the Alvarez team made the discovery of the iridium anomaly that led to a new interpretation of the extinction of the dinosaurs and much of the other life on the planet at the K/T boundary. Unfortunately, I was trapped on a bus that was not under my control, and we didn't have time to stop for better composed pictures.