Earthquake Visualization Tools – I


Earthquake Visualization Tools – An Introduction


The vast majority of earthquakes occur below ground and never cause a physical break in the surface land. When this does happen it can be dramatic, as seen in this photo of a fence in Pt. Reyes split by the 1906 San Andreas earthquake. But researchers need to see inside the ground and the public needs an easy way to understand the complex geology and seismology of these events that can literally change our lives.

In this series of Posts we will look at four different types of visualization tools:

  • Earthquake monitoring — historic and today’s real-time monitoring and notification
  • Earthquake mapping — digital, on the Web, Smartphone apps
  • Earthquake scenario tools designed to illustrate what might happen
  • Modeling tools for geophysical study of fault structures and slippage

Most of these are readily available to the general public and give us all access to a better understanding of what may, and does, happen when the earth really moves beneath our feet.

California and Mexico Working Together to Reduce Earthquake Losses

San Diego/Tijuana Earthquake Scenario
What is involved in a scenario plan? And Why Update it

In 1990 EERI created a scenario study of an earthquake along the San Diego/Tijuana Border area.  And now, as we discussed in an earlier Post, they are doing a new one.  Today there are more buildings, more people, our understanding of earthquakes is greater and we have new tools to develop the scenario; ultimately to help keep the people in the region safer in case of a major earthquake.

When we talk about scenarios what is involved?  The EERI 2017 project includes dozens of different experts in three working groups. They cover the geotechnical issues, infrastructure and economics and social impacts.  A deeper look at the infrastructure team gives us a better understanding of what has changed since 1990. This is their work scope:

  • Lifelines (water, wastewater, power, communications, natural gas and liquid fuels, dams)
  • Transportation (roads/highways, bridges, ports, rail).
  • Buildings (URM/unreinforced masonry/brick, historic buildings, commercial and residential, low-rise, mid-rise, high- rise, pre-1980 concrete, post-1980 concrete, pre-Northridge steel, industrial facilities, open-front buildings).
  • Essential Facilities (hospital, schools, police and fire stations, airport etc.).
    • Health & school systems on both sides of the border
  • Border Stations
  • Risk Assessment & Loss Modeling

This project helps illustrate that earthquakes do not recognize international boundaries.

The San Diego/Tijuana Earthquake Scenario


At 7:31AM on May 16th 2017, a Magnitude 7.0 Earthquake occurred along the Rose Canyon Fault off of San Diego at location 32.850°N, 117.258°W at a depth of 4.9 km.

Only it didn’t, it was just a scenario, prepared by the USGS with the Earthquake Engineering Research Institute to help develop plans for risk reduction in the Tijuana/San Diego region. This region is home to more than 5 million people, with interconnected and interdependent economies and infrastructures.  The scenario, and others like it, help answer questions like:

  • How prepared is the region in the case of a major earthquake?
  • What types of damages and impacts can be expected and perhaps more important, what types of impacts may be unexpected?
  • What will the social and economic impacts be to the region?
  • And what can be done now to improve earthquake safety and resilience?

This is a volunteer effort, involving architects, geologists, seismologists, emergency managers, planners, building officials, and even social scientists and economists. They are working in three interconnected teams to help put together an integrated view of the event and what might happen and how best to respond:

  1. Earth Science – What is likely to happen when the fault slips?
  2. Engineering – How are structures designed and how will they respond?
  3. Social Science – What are the impacts on the social systems and economics of the region?

Multiple partners, working together, will prepare recommendation on how to improve resilience and recovery.

Priority Recommendations from the PEER Study on the South Napa Earthquake


The M 6.0 South Napa Earthquake of August 24, 2014, was the first earthquake to strike a major metropolitan area in the State of California in over two decades. During that quiescent period, the State’s population grew significantly, thousands of new businesses were started and thousands of new buildings were built. This means that the 2014 South Napa quake has provided an opportunity to learn about how we plan for, build for, and respond to earthquakes, as well as educate millions of Californians who are ‘new’ to earthquakes about them.

In October 2014, the Seismic Safety Commission held a public hearing in American Canyon, California, to better understand impacts and lessons learned from the South Napa earthquake. The Commission engaged its longtime partner, the Pacific Earthquake Engineering Research Center based at UC Berkeley, to research and report on the impacts and lessons learned from the earthquake.

The 55 page report contains 12 “Priority Recommendations,” which are important for anyone living or working in California. The majority is in the ”structures” category, since improvements in our built environment has perhaps the most direct positive impact on safety and recovery. These are presented below and organized under the same headings as the report.

  1. Geosciences
    • Identify the locations of complex and integrated fault zones in the state, like the West Napa Fault Zone, and prioritize these for evaluation and mapping and potential designation as Alquist-Priolo Earthquake Fault Zones.
    • Evaluate the effects of current amendments and exemptions under the Alquist-Priolo Earthquake Fault Zone Act and accompanying regulations, and study ways to better regulate and fund geologic investigations and structural mitigation in Alquist-Priolo Earthquake Fault Zones.
  2. Infrastructure
    • Ensure that all State-required gas safety plans address the mitigation of system risks to seismic hazards.
    • Convene a State task force that includes local water and wastewater providers as well as fire departments across the state to identify vulnerabilities, mitigation options, and financial mechanisms to enhance the seismic resilience of local water and wastewater systems, particularly in areas vulnerable to widespread ground failure and that lack alternative water supplies for firefighting.
  3. Structures
    • Work with FEMA, the California Building Officials, and other professional engineering and architectural organizations to: ensure that curricula for training and certification of safety assessors are effective and more widely implemented, particularly for local government personnel; improve protocols for deploying and compensating safety assessors; expand the use of Building Occupancy Resumption Programs; and grant safety assessment authority to the Division of the State Architect for public K-14 schools and State-owned buildings.
    • Work with the California Building Officials and professional engineering and architectural organizations, including the American Institute of Architects California Chapter and Structural Engineers Association of California, to develop guidance for local jurisdictions on effective coordination and management of post- earthquake safety assessment processes.
    • Develop guidance and training for local fire departments and building owners and operators on alternative procedures to safely turn off damaged sprinkler systems following earthquakes.
    • Evaluate and enhance, as needed, training and inspection materials for school districts and staff to seismically secure non-structural systems, equipment, contents and furnishings in public and private schools.
  4. People and Businesses
    • Establish a State task force to consider the risks posed to the state by the large proportion of uninsured residents and businesses in high-seismic hazard areas, and identify options for improving the take-up, affordability, and terms of earthquake insurance coverage for California residents and businesses, as well as alternative earthquake recovery funding sources for both residents and businesses.
    • Evaluate and enhance, as needed, penalties and other consumer protections against post-disaster scamming by contractors and cost inflation.
  5. Government and Institutions
    • Strengthen seismic performance standards and contingency planning for all State and local correctional facilities.
    • Review and revise, as needed, State regulations guiding the transfer and housing of inmates in county jails during times of emergency.

Key Findings from the PEER Report on the 2014 South Napa Earthquake


The M 6.0 South Napa Earthquake of August 24, 2014 took the lives of two people, injured 300 others, and caused moderate to severe damage to more than 2,000 structures. The Commission engaged the Pacific Earthquake Engineering Research Center (PEER) to research the impacts and lessons learned from the quake and prepare a comprehensive report.

The report is organized around the areas of Geosciences, Infrastructure, Buildings, People and Businesses, and Government and Institutions.

The full report is 55 pages with great research and detail.  In a later Post we will cover the recommendations, here we provide some of the key findings:

  1. Geosciences
  • Afterslip (slippage on the fault after the principal earthquake) on the West Napa fault produced further damage and necessitated regional-scale on-going monitoring.
  • The S earthquake identified some critical gaps in mapping coverage and guidance that affected the abilities of city, county, and State agencies to identify and map hazard zones.
  1. Infrastructure
  • Investments in instrumentation, earthquake alerting systems, and advance remote sensing techniques plus the activation of the California Earthquake Clearinghouse all were valuable in assisting damage assessment and emergency response.
  • The earthquake demonstrated the long-term benefits of the State’s $12 billion highway bridge earthquake strengthening program.
  • The earthquake highlighted the vulnerability of natural gas transmission and distributions systems to earthquake-related ground failure.
  • The earthquake highlighted the vulnerability of water and wastewater systems to earthquakes, plus the hazards that earthquake-related water-system failures can pose.
  1. Structures
  • The earthquake helped to identify important gaps in building safety evaluations and procedures to barricade unsafe areas.
  • The City of Napa’s program to seismically retrofit unreinforced masonry buildings was successful in reducing damage and the risk to life safety posed by these buildings.
  • While modern buildings generally met or exceeded code performance standards in the Mw6.0 earthquake, damage to non-structural components was the greatest contributor to property losses.
  • There was generally good performance across a range of wood-frame residential construction vintages and styles. The vast majority of damage was caused by two well-known seismic deficiencies: unbraced chimneys and cripple walls foundations.
  • The significant damage to manufactured housing in the 2014 South Napa earthquake was almost exclusively associated with support systems rather than the homes themselves.
  1. People and Businesses
  • Deaths and injuries sustained in the earthquake point to continuing gaps in public awareness and education on earthquake safety and preparedness.
  • The earthquake highlighted gaps in earthquake insurance coverage for both homeowners and businesses.
  • The delay of the federal Individual Assistance program hindered recovery.
  1. Government and Institutions
  • The state’s Standardized Emergency Management System (SEMS) was effective in mobilizing a multi-jurisdictional, multi-level emergency response but significant areas for improvement and training have been identified.
  • The earthquake identified problems with the damage assessment and declaration processes and financing of local government post-disaster assistance.
  • The earthquake highlighted significant gaps in contingency planning at many key government and critical facility operations.
  • More pre-disaster planning and training for post-disaster recovery is needed at both the State and local levels.

Major earthquakes can cause damage and loss, but California has a history of studying and learning from earthquake to make our State safer for residents and businesses.  The Commission supported study by PEER is the most recent example of such efforts.

A Wake-up Call for Renewed Investment in Seismic Resilience across California


The M 6.0 South Napa Earthquake of August 24, 2014 took the lives of two people, injured 300 others, and caused moderate to severe damage to more than 2,000 structures.


On October 8, 2014, the Seismic Safety Commission held a public hearing in American Canyon, California, to better understand impacts and lessons learned from the South Napa earthquake. The Commission engaged the Pacific Earthquake Engineering Research Center (PEER) to research the impacts and lessons learned from the quake and prepare a comprehensive report.  Because the South Napa Earthquake was the first earthquake to strike a major metropolitan area in California in over two decades it was the opportunity for a wake-up call to renew investment and action to enhance the seismic resilience of communities, businesses, and residents across the state. The 55 page PEER report is organized around the areas of Geosciences, Infrastructure, Buildings, People and Businesses, and Government and Institutions.

Based on their research PEER presents 20 key findings and makes 12 priority recommendations which we will cover in detail in our next Posts.

Mother Nature Delays Tsunami Test in Northern California


In October 2017 The National Weather Service and the Redwood Coast Tsunami Work Group in Humboldt County (RCTWG) planned to have a tsunami test.  The test exercises the ability to successfully alert the public to a tsunami risk and, when there is enough time, for coordinated evacuation activities. When a tsunami comes from far away, like Alaska or Japan there can be is enough time to plan for and execute a safe evacuation.

The first time there was a tsunami communications test in Humboldt County was in March 2008, exercising the response system as if a real tsunami had occurred including the Emergency Alert System (EAS). The community worked hard to make sure that everyone was aware of the test, especially people at high risk to not hearing or understanding the alert, the hearing impaired and non-English speakers. The 2008 test only included Humboldt but over time it expanded to Del Norte and Mendocino Counties. The test has been run each year since 2008 except 2011, when there a real tsunami from a Japanese earthquake generated a real alert.

This year the RCTWG decided to change the timing of the 2017 test exercise to October, to coincide with the Great ShakeOut earthquake exercise, the same as communities in coastal Oregon and Washington.  But a successful tsunami test depends on the citizens understanding what to do when the alert sirens sound and they receive evacuation notices.  This requires education on what to do, and to insure people know it will be a test, and only a test.  The fires in northern California made it hard to do a test, not only because many of the emergency personnel were actively fighting fires, but also because the citizens might think that sirens sounding and the EAS system going off meant a real disaster was about to hit.

The communities still took part in the Great ShakeOut on Thursday Oct. 19 and practiced DROP, COVER and HOLD ON.  Everyone living or traveling in coastal California should know what to do in the case of a tsunami, they can come suddenly and often without warning, especially when triggered by a local earthquake. You can find earthquake and tsunami preparedness information in “Living on Shaky Ground: How to Survive Earthquakes and Tsunamis in Northern California” available here along with other preparedness information.

It pays to be prepared, as the people of the north coast know well, Mother Nature will always surprise.


This post is based in part on a story filed in the Eureka Times Standard by Professor Lori Dengler, a Commission Partner and emeritus professor of geology at Humboldt State University. Professor Dengler is the co-author of “The Extraordinary Voyage of Kamome,” a tsunami education book sponsored under a Seismic Safety Commission grant.

How the Best Prepare – Japan

What California Can Learn From Japan


On the morning of September 1, 1923, a massive earthquake shook Japan’s Kanto Plain, devastating the capital Tokyo and the coastal industrial city of Yokohama. As in the San Francisco earthquake 17 years earlier, fire followed the shaking and by the time the earthquake-caused tsunami receded over 140,000 were dead. The destruction of Tokyo was so great that Japan considered moving the capital to another, safer city. Tokyo is still the capital of Japan and it is one of the safest big cities in the world to be in during an earthquake.

After the 1923 earthquake, Japan experienced more seismic events, most recently the 2011 M9 Tōhoku earthquake and tsunami. After each event, the country got better at preparedness, and today it is the world’s leader. There is national culture of preparedness, a national earthquake early warning system and some of the most seismically effective building codes anywhere. When it comes to earthquakes and getting prepared, Japan is a model for California.

Every year since 1960, Japan marks Disaster Prevention Day on September 1st. Schools start the day with an evacuation drill. The Prime Minster is involved, and at a recent Disaster Prevention Day he talked about the importance of mutual aid, stating. “I would like to ensure that the government will prepare itself for disaster, together with the people, so that it can confidently say that ‘Providing is preventing.’”

For more than a decade the country has had a national earthquake early warning system that is tied to the radio, TV and mobile companies for instant notification. Japan’s tsunami warning system is more than 65 years old and boasts over 300 censors that together with sophisticated computer systems can predict the height, speed, location and arrival time of any tsunami.

In 1981 Japan updated its building codes based on seismic research, and the 1995 Kobe earthquake led to increased research and a new set of building codes. In 2000, these codes were revised, incorporating specific requirements and mandatory checks. In response to the 1995 earthquake, where more than 4,000 schools were destroyed, Japan passed its own version of California’s Field Act, making every school resilient to the impact of earthquakes.  Since 2002 the percentage of earthquake-resistant public elementary and junior high schools in Japan has increased from fewer than half of schools to more than 95 percent in 2015.

We can always do better to make our citizens safer; learning from Japan is one important and valuable way.

The Ring of Fire


California is earthquake country and is located within “The Ring of Fire, a horseshoe-shaped, 40,000 km-long string of seismically active zones and volcanoes around the Pacific Ocean. Almost 90% of all the earthquakes in the world occur along the Ring of Fire, and 75% of all of the Earth’s active volcanoes lie along the Ring.

Caused by the movement of tectonic plates, giant slabs of the Earth’s crust, earthquakes along The Ring of Fire occur as these plates collide and either strike each other or one moves above or under the other. These collisions not only cause earthquakes, they also create mountain ranges, and because hot magma from the Earth’s core can escape along these ‘seams’ in the Earths crust volcanoes grow and erupt.

The M 7.8 1906 earthquake along the San Andreas Fault was caused by just such a collision and killed an estimated 4,000 people. But 17 years later another earthquake along The Ring of Fire caused approximately 140,000 deaths when a M 7.9 earthquake, known as the Great Kantō, struck Japan, devastating Tokyo and Yokohoma. As was the case in 1906 in California, the Great Kantō earthquake was followed by fires that caused further destruction. But in Japan they experienced a massive tsunami as well, one that reached almost 40 feet high in places.

Today Tokyo and Japan have some of the strongest seismic building codes in the world, and since October 2007 Japan has had a national earthquake early warning (EEW) system. Japan has a culture of preparedness; every year on September 1st, the anniversary of the 1923 Great Kantō earthquake, Japan observes National Preparedness Day. In reflecting on this national approach to preparedness, UN Secretary General Ban Ki-moon held up Japan’s disaster preparedness efforts as a model to the world, saying in 2016 that, “…the rest of the world has much to learn from Japan, if we are to make progress on saving lives and livelihoods, and reducing disaster losses.”

In our next Post we will learn more about Japan’s preparedness.

Overcoming Obstacles to Getting Prepared

Why Don’t People Prepare?


A recent Federal Emergency Management Agency (FEMA) survey found that nearly 60% of American adults have not practiced what to do in a disaster and only 39% have developed an emergency plan. This is despite the fact that 80% of Americans live in counties that have been hit with a weather-related disaster since 2007, as reported by the Washington Post. With the number and severity of weather-related disasters on the rise, the America’s PrepareAthon! is an opportunity for individuals, organizations, and communities to take action to prepare for specific hazards through group discussions, drills, and exercises.

But why don’t people prepare? In their new book, The Ostrich Paradox, Why We Underprepare for Disasters, authors Robert Meyer and Howard Kunreuther from the Wharton School at the University of Pennsylvania suggest there are six key reasons:

  • Inertia: The feeling that you don’t need to protect yourself yet.
  • Myopia: The irrational feeling that since things are fine now and have been fine for as long as you’ve been in the area, they’ll continue to always be fine.
  • Herding: Looking to others to tell you what to do to prepare for a disaster and not doing it if you do not see an authority telling you to.
  • Optimism: While this is normally a positive trait, in the event of a disaster it can make you downplay the risks and thus fail to take adequate measures to protect yourself.
  • Amnesia: No matter how badly natural disasters damage an area people are quick to forget these events and the lessons that should have been learned from them.
  • Simplification: A lack of awareness of the full extent of damage that a natural disaster can cause and the scenarios that a family will be in if they’re caught in one (i.e., how they are going to get out of the area if the roads are shut down).

Alan Jacobs and Scott Matthews from the University of British Columbia offer a complementary explanation in their paper, “Why Do Citizens Discount the Future?”.  In it, they discuss experimental research designed to answer that question and conclude that citizens’ bias towards the present derives in large part from uncertainty about the long term. Their work was designed for public policy, but this research supports theories about “temporal discounting” and suggests that risks that are perceived to be years away or uncertain have little motivational force in our behavior.

All of these may be valid reasons, and the research is important to understand human behavior regarding preparedness. But a major earthquake will happen, we must prepare for it, and perhaps need to overcome our normal tendencies in order to do so.