Category Archives: Earthquake

2018 USGS Hazard Map Updates: Is RMS Revising the U.S. Earthquake Model?

In March 2018, RMS hosted the U.S. Geological Survey (USGS) workshop at our Newark headquarters in California to discuss the interim updates planned for the 2018 USGS National Seismic Hazard Map Project (NSHMP). Details can be found in my previous blog: Are You Ready for an Interim USGS NSHM Update?

The USGS informed the public and technical community about this interim update ahead of their regular six-year cycle of updates anticipated after 2020. The main purpose was to incorporate new ground motion modeling advances for Central and Eastern U.S. from Project 17, which has significant value for the national building code (details can be found here).

Towards the end of 2018, the USGS published the draft document and national hazard maps to receive scientific peer review and public feedback from the user community (Petersen et al. 2018). Since then, the USGS has been very busy incorporating the updates and finalizing the models. In December 2019, they published the official 2018 USGS NSHMP document in the Earthquake Spectra journal.

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Haiti Earthquake: Ten Years On

This week marks the tenth anniversary of the devastating earthquake in Haiti. The magnitude 7.0 event ruptured a thrust fault associated with the Enriquillo-Plantain Garden fault system 25 kilometers (16 miles) west of the capital city Port-au-Prince. This fault system runs along the length of the Tiburon Peninsula and is no stranger to earthquakes, with major events impacting Haiti in both 1751 and 1770. This large time gap since the last major events meant that there was little to no societal memory or preparedness for earthquakes in the region, making the 2010 event particularly devastating.

In the 2010 event, the strong ground shaking lasted 30 seconds and caused extensive collapse of masonry and concrete structures due to both poor design and construction practices, and poor construction material quality. An estimate for the resulting death toll is a staggering 150,000 people.

The scale of the damage and the number of people killed impacted all aspects of life for the remaining inhabitants of Port-au-Prince and the surrounding regions. Vital infrastructure including hospitals, communication systems and transportation facilities (e.g., the airport and port in Port-au-Prince) was severely damaged or destroyed, hampering disaster response. With 250,000 homes severely damaged, more than one million people needed to be housed and fed.

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Newcastle: Thirtieth Anniversary of Australia’s Largest Earthquake Loss. But What If…?

Over the past 15 years, we have witnessed some of the world’s largest possible recorded earthquakes that have had catastrophic impacts around the globe. But, looking back 30 years to 1989, we saw two smaller, but still significant earthquakes. The first was the M6.9 Loma Prieta event that hit the San Francisco Bay Area in October, an earthquake that is familiar to many due to its proximity to the city, and its level of destruction. However, less are aware of the other notable earthquake that year. December 28, 1989, is a memorable date for many Australians; as it marks the country’s most damaging earthquake in recorded history, and still remains one of Australia’s costliest natural catastrophes to date.

Despite its moderate magnitude, the M5.4 Newcastle earthquake caused widespread ground shaking, with insured losses of just under $1 billion AUD (US$690 million) at the time of the event (ICA, 2012), a loss which if the earthquake was repeated, RMS estimates would cost over $5 billion AUD.

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Nine Years After Darfield: When an Earthquake Drives a New Model – Part Two

The Liquefaction Model

The 2010 M7.1 Darfield earthquake in New Zealand started a sequence of events – the Canterbury Earthquake Sequence (CES), that propagated eastward in the Canterbury region over several years. Since the City of Christchurch is built on alluvial sediments where the water table is very shallow, several of the larger events created widespread liquefaction within the city and surrounding areas. Such ground deformations caused a significant number of buildings with shallow foundations to settle, tilt and deform.

Prior to these New Zealand earthquakes, liquefaction was observed but not on this scale in a built-up area in a developed country. As in previous well-studied liquefaction events (e.g. 1964 Niigata) this was a unique opportunity to examine liquefaction severity and building responses. Christchurch was referred to as a “liquefaction laboratory” with the multiple events causing different levels of shaking across the city. However, we had not previously seen suburbs of insured buildings damaged by liquefaction.

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Nine Years After Darfield: When an Earthquake Drives a New Model – Part One

The Source Model

The 2010 M7.1 Darfield earthquake in New Zealand started a sequence of events that propagated eastward in the Canterbury region over several years, collectively causing upward of 15 individual loss-causing events for the insurance industry. The Insurance Council of New Zealand state that the total insured loss was more than NZ$31 billion (US$19.4 billion).

With such a significant sequence of events, a lot had to be learned and reflected into earthquake risk modeling, both to be scientifically robust and to answer the new regulatory needs. GNS Science – the New Zealand Crown Research Institute, had issued its National Seismic Hazard Model (NSHM) in 2010, before the Canterbury Earthquake Sequence (CES) and before Tōhoku. The model release was a major project, and at the time, in response to the CES, GNS only had the bandwidth for a mini-update to the 2010 models, to allow M9 events on the Hikurangi Subduction Interface, New Zealand’s largest plate boundary fault, and to get a working group started on Canterbury earthquake rates.

But given the high penetration rate of earthquake insurance in New Zealand and the magnitude of the damage in the Canterbury region, the (re)insurance and regulatory position was in transition. Rather than wait for a new National Seismic Hazard Map (NSHMP) update (which is still in not available), RMS joined the national effort and started a collaboration with GNS Science as well as our own research, to build a model that would help during this difficult time, when many rebuild decisions had to be made. The RMS® New Zealand Earthquake High Definition (HD) model was released in mid-2016.

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Did Ridgecrest Increase the Chances of a Large Seismic Event?

Interest in the 160-mile-long Garlock Fault, the second-largest fault in California, has been piqued recently after a Los Angeles Times article about deformation on the Garlock Fault due to the Ridgecrest sequence of events in July 2019. Since the publication of this article, RMS has received information requests focused around two main points.

First, does RMS believe that Ridgecrest impacted the Garlock Fault (and possibly others), and has therefore increased the probability of a rupture there? Second, does RMS support the assumption from the U.S. Geological Survey (USGS) that the most likely scenario is that the Ridgecrest quakes probably won’t trigger a larger earthquake, but have raised the chances of an earthquake of magnitude 7.5 or more on the nearby Garlock, Owens Valley, Blackwater and Panamint Valley faults over the next year. And how would RMS recommend that clients model and capture this increased risk?

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MyShake: New App Unveiled for California Earthquake Early Warning

As my colleague Mohsen Rahnama reminded us in his recent blog, the last destructive earthquake to strike Northern California was on October 17, 1989. Loma Prieta was a magnitude 6.9 earthquake which resulted in 63 deaths and about four thousand injuries. The epicenter was about ten miles northeast of Santa Cruz, and seismic waves took about 30 seconds to reach San Francisco. But there was no way of communicating any earthquake early warning to residents of the Marina district of San Francisco, which suffered some of the worst damage from shaking and fire outbreak.

On October 17, 2019, the thirtieth anniversary of this earthquake, the California Governor’s Office of Emergency Services unveiled a smartphone app from the University of California, Berkeley Seismological Lab that will give all Californians the opportunity to receive earthquake early warnings.

Governor Gavin Newsom, who happened to be in the Marina district at the time of the 1989 earthquake, has urged people to download the MyShake app. This app (myshake.berkeley.edu) is available on the Apple App Store and Google Play, and relies on the ShakeAlert earthquake early warning system, developed by the U.S. Geological Survey (USGS).

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Loma Prieta and 30 Years of Bay Area Growth

Thirty years ago, the Mw6.9 Loma Prieta Earthquake struck the San Francisco Bay Area. When looking back at disasters, it is always particularly relevant to understand the moment in time impacted. The Loma Prieta Earthquake struck on Tuesday, October 17, 1989 at 5:04 p.m. local time, but it was no ordinary Tuesday afternoon. Game Three of the Major League Baseball 1989 World Series was to start at 5:35 p.m. between the two Bay Area teams: the Oakland Athletics and the San Francisco Giants.

Typically, 5:04 p.m. would represent the height of rush hour in the Bay Area, but because of the game a significant component of the workforce had left work early or had stayed late to watch it. While 63 lives were lost, this loss level was much lower than it might have been given the level of damage that impacted highways across the region including the failures of the Nimitz Freeway and the San Francisco–Oakland Bay Bridge.

I was at Stanford University in the Terman Engineering Building studying when the earthquake struck. The Stanford campus made up of numerous historical buildings saw substantial damage. In all, more than 200 structures were impacted. The restoration of the damage took more than a decade to fix and cost Stanford more than US$160 million. Classes were canceled for more than a week. Students were locked out of damaged buildings which meant they could not access their research samples, data and equipment. Adding to the stress were the innumerable aftershocks. For those of us studying engineering, it really brought home the importance of our work.

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The Year of the Kitten

Almost three months ago we passed a remarkable record in catastrophe loss.

And yet no one seems to want to celebrate it.

No banner headlines in the newspapers. No speeches at the Monte Carlo Reinsurance Rendezvous.

The first half of 2019 generated the lowest catastrophe insurance loss for more than a decade. The estimates come in at: US$15 billion (Munich Re), US$19 billion (Sigma), or US$20 billion (Aon). In straight dollar terms, independent of any adjustment for inflation or exposure, this is lower than any year since 2006.

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EXPOSURE Magazine: Looking Ahead to the Next Ten Years

The year 2020 is just months away, and in the latest edition of EXPOSURE — the RMS magazine for risk management professionals, we consider some of the changes that the (re)insurance industry will have undergone in ten years’ time. Mohsen Rahnama, Cihan Biyikoglu and Moe Khosravy from RMS tackle the issues, examining the evolution of risk management, the drivers of technological change, and how all roads lead to a common, collaborative industry platform.

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