Research Products and Deliverables

Since the ERP was formed in 2017, the ERP has generated a total of nearly 400 peer-reviewed research products, including 90 journal articles, 20 USGS series products (for example, USGS Open-File Reports), 15 book chapters and cooperator publications, multiple data releases and USGS web pages, and more than 250 abstracts and conference proceedings. The ERP manages several online resources that provide earthquake ground motions for engineering design based on the USGS NSHM (https://earthquake.usgs.gov/hazards/designmaps/) as shown in figure 2. These resources include web services to access seismic design parameters for user-defined locations throughout the United States for U.S. building codes (for example, the American Society of Civil Engineers/Structural Engineering Institute [ASCE/SEI] standard for new buildings [ASCE/SEI. 2022], and the American Association of State Highway and Transportation Officials guide specification for bridge design [American Association of State Highway and Transportation Officials, 2024]). These web resources have been developed and maintained by the ERP through various editions of its guidelines and specifications. The ERP also provides tools for computing risk-targeted ground motions (fig. 3).

In particular, the seismic design web resources provide multiple third-party web graphical user interfaces with access to seismic design parameters (for example, the 2020 NEHRP Recommended Seismic Provisions for New Buildings and Other Structures tool by the National Institute of Building Sciences [https://www.nibs.org/reports/bssc-tool-2020-nehrp-provisions-seismic-design-map-values], American Society of Civil Engineers Hazard Tool [https://ascehazardtool.org], and Structural Engineers Association of California (SEAOC) and California’s Office of Statewide Health Planning and Development (OSHPD) Seismic Design Maps Tool [https://www.seismicmaps.org]. Users from the United States and throughout the world access USGS design motion web services about 3 million times per month by a combination of direct access, third-party graphical user interfaces, and application programming interfaces such as Python or MATLAB (E. Martinez, U.S. Geological Survey, unpub. data, 2024).

Members of the ERP also collaborate with the NSHM and external partners on nationwide seismic risk modeling of buildings (fig. 4) and other infrastructure (fig. 5). They also collaborate with the National Earthquake Information Center on the Prompt Assessment of Global Earthquakes for Response (PAGER) system (https://earthquake.usgs.gov/data/pager/) development efforts. The PAGER system provides near real-time estimates of fatality and economic loss following significant earthquakes anywhere in the world, thereby contributing to risk reduction research and application.

External Service and Collaboration

The ERP serves a critical role supporting the NSHM project and contributing to the development of NSHMs in several ways. As one of the first engineering users of NSHM, the ERP provides critical feedback and guidance on developing and implementing new ideas within the NSHM. Additionally, the ERP devotes significant time engaging with the broader practicing engineering and risk research community so that new science gets effectively used and communicated among the wide range of stakeholders. As part of that role, the ERP members serve on numerous external committees and governing bodies to communicate USGS science to various stakeholders and aid in the adoption of NSHM-related engineering design loads into U.S. building codes. For example, ERP members have been a fixture as Federal agency liaisons on the BSSC, which is primarily responsible for updating the NEHRP seismic design provisions on a 5-year cycle. Other standard bodies that the ERP coordinates with and contributes to include the American Association of State Highway and Transportation Officials, American Society of Civil Engineers, and the America Railway Engineering and Maintenance-of-Way Association.

Members of the ERP collaborate internally with geologists, geophysicists, and engineering seismology researchers; computer scientists from the Ground Motion, NSHM, Advanced National Seismic System, Earthquake Geology, and Hazards Development (HazDev) projects at the GHSC; and civil engineering and geophysics researchers from the Shaking, Damage, and Failure project and Pacific Northwest Earthquake Hazards Study project at the USGS Earthquake Science Center (ESC), and the Tsunami and Earthquake Research project at the USGS Pacific Coastal and Marine Science Center. External collaborators include numerous researchers in academia and other government agencies, as well as engineering practitioners from around the United States. The ERP contributes to cross-agency collaborative efforts with Federal agencies and departments, such as:

Personnel

The ERP team currently (2025) consists of 5 scientific staff, including student interns, who spend their time assisting on ERP-led research. The ERP currently (2025) consists of earthquake engineering researchers with backgrounds in civil, structural, and geotechnical engineering. The ERP also coordinates and conducts non-EHP research on topics covering rockfall hazards (Stock and others, 2014) and work across the USGS Natural Hazards Mission Area evaluating the risk of copper and rhenium supply disruption from global earthquakes (Jaiswal and others, 2024).

Table 1 shows the project tasks and key activities conducted within the ERP by engineering discipline. Members of the ERP have broad expertise in many disciplines, including:

Improvements to the U.S. Seismic Design Guidelines (Building Codes)

The ERP currently (2025) plays a critical role as a two-way interface between NSHM products and the earthquake engineering community. The ERP has historically been the primary resource for presenting the NSHM and its periodic updates to practicing engineers. In one direction, the ERP is responsible for clarifying and explaining the advances in the science that underpins the NSHM (for example, changes to the earthquake rupture forecast, ground motion modeling, and characterization of sedimentary basin and coastal plain amplifications) and how those advances affect the resulting design ground motions to the committees that write building codes. In the other direction, the ERP receives feedback from committees on how the NSHM can be updated to enhance engineering practice (for example, more guidance on hazard uncertainties, deterministic earthquake design scenarios, and hazard disaggregation data) and collaborate with NSHM project personnel to assess the feasibility and ultimately deliver such improvements to users. This role is evident in the involvement of ERP personnel as NEHRP agency liaisons to several building code-writing committees, such as BSSC, the American Association of State Highway and Transportation Officials, and others.

Within the context of building codes, ERP researchers have also performed critical research on developing design ground motions and engineered significant improvements to how NSHM hazard data are used in the engineering community (for example, risk-targeted design motions, improvements to site effects, adoption of multiperiod response spectra, and rational incorporation of deterministic earthquakes). These efforts are another example of ERP’s role as a two-way interface between USGS earthquake science and the engineering community. The ERP is keen to continue expanding on this research into the future. Such efforts include the following:

Improvements to the U.S. Geological Survey Seismic Hazard Characterization

One of the flagship USGS earthquake science products is the NSHM, which provides valuable information to users on the levels of expected ground shaking from a variety of seismic sources across the United States. Although knowledge of ground shaking hazards is a crucial starting point in understanding how earthquakes may affect human populations, one of the most important uses of the NSHM comes from how it is translated into more actionable information to stakeholders, and, just as importantly, how the NSHM can be improved to enhance its utility for risk-based applications.

To that end, the ERP continues to be well-positioned to use internal and external research, as well as interactions with stakeholders, to facilitate collaboration with the NSHM project to improve its utility as a tool in risk assessment and mitigation. Such ongoing and future efforts include the following:

Risk Assessment

Among the four agencies within the NEHRP, the USGS is the only agency with the stated responsibility of researching and assessing earthquake risks (42 U.S.C. 7704(b)(3)). To assist the USGS with this responsibility, the ERP provides engineering expertise and direct leadership in the estimation and communication of seismic risks. Ensuring that estimated risk information is actionable for decisionmakers and stakeholders requires appropriate communication of risks and the associated uncertainties. Equally important, feedback from stakeholders enhances the quality of the hazard science and subsequent risk assessments.

In addition to figure 1, the distinction between hazard and risk is further illustrated in figure 5. The figure shows the seismic risk to natural gas transmission pipelines in the conterminous United States. The map in figure 5 was originally developed by Kwong and others (2022) by combining the 2018 USGS NSHM map, a logic tree-based exposure model, three different vulnerability models, and a consequence model. Seismic risk is expressed using the average annual cost required to repair pipelines that may be damaged from strong ground shaking alone and, hence, can be interpreted as a lower bound of the actual risk. The dark regions for example, from California, parts of Oregon, Washington, Arizona, and others indicate counties that carry high risk, relative to other counties (fig. 5). Comparing the geospatial distribution of risk against that of hazard demonstrates that two different geographic regions with differing hazard can carry similar levels of seismic risk. For example, although the earthquake hazard in Arizona is less than that in Washington (Petersen and others, 2024), the seismic risk to natural gas transmission pipelines in both States are within a similar order of magnitude. Such discrepancies between hazard and risk arise from differences in exposure (for example, total mileage of pipelines), vulnerability (for example, likelihood of seismic damage), and consequence (for example, costs required to repair a leak). Therefore, changes in seismic risk between USGS NSHM update cycles are not necessarily commensurate with changes in hazard.

To reduce adverse effects of earthquakes on the built environment, seismic risk needs to be assessed routinely and systematically. The ERP has been an integral part of assessing risks for many ongoing projects. For example, the ERP assists, maintains, or enhances many of the USGS products (for example, NSHM, PAGER, and ShakeCast [https://www.usgs.gov/publications/earthquakes-shakecast/]). Ongoing projects and examples of actions taken include the following:

The ERP is well-positioned to continue and expand on risk research into the future. Although current (2025) ERP members are mostly involved in responding to the foundational priorities, some staff have engaged in conducting original engineering research in several areas, mainly through the support of term and temporary staff. However, some of these activities may not continue because of the lack of permanent sources; such efforts include the following:

Geotechnical and Geohazards Research

The USGS has a strong history of research in the field of geotechnical earthquake engineering, beginning in the 1980s with work primarily performed at the ESC and the USGS Pacific Coastal and Marine Science Center in northern California, and with more recent efforts from the GHSC. Such efforts were historically geared towards field reconnaissance missions to observe postearthquake geotechnical damage. These studies have been effective for understanding soil liquefaction hazards and a foundational component of modern-day geotechnical earthquake engineering (DuRoss and others, 2024). Since then, USGS geohazards research has also focused on instrumented sites, development of methods for the prediction of earthquake-induced ground failure, and geotechnical site response. Although this research has been critical in advancing the scientific understanding of geohazards, gaps in translating this science into seismic design policy have persisted for decades and represent a key area of growth potential. The ERP’s recent addition of geotechnical personnel and expansion of geohazards-related research objectives is aimed at addressing these needs.

One of the critical ongoing efforts within ERP is research on, and the development of, computational tools for probabilistic liquefaction hazard analysis (PLHA; for example, Makdisi and Kramer, 2024b). This framework makes use of, and extends, the NSHM to provide estimates of hazards from earthquake-induced liquefaction and its consequences at any site within the United States, in terms of annualized probabilities of various liquefaction triggering limit states (fig. 7). As of 2024, it is being used in ERP research efforts to improve seismic design guidelines for the assessment of liquefaction-induced ground failure in the NEHRP provisions (refer to the “Improvements to the U.S. Seismic Design Guidelines (Building Codes)” section). The long-term potential for this project is the release of a planned USGS PLHA computational platform to serve as a resource for practicing engineers and researchers in earthquake geotechnics and have a comparable level of use as the NSHM in design practice and research. The development and implementation of this resource would involve coordination among the ERP and NSHM groups, as well as the establishment of a USGS-led working group that would provide valuable interactions with academic researchers, industry partners, and Federal agency personnel.

Given the personnel and expertise within the ERP, as well as the collaborative connections to USGS researchers with geotechnical expertise within other GHSC and ESC projects, the ERP has identified several areas of ongoing and future expansions in geotechnical research capabilities, including the following:

Simulation, Validation, and Use of Earthquake Ground Motions

One of the most significant challenges in earthquake hazards research is the lack of high-quality earthquake observations, especially near-source observations, particularly given the lengthy geologic timescales through which such observations are needed to make meaningful conclusions about earthquake occurrences and effects. Among the most promising approaches for addressing this limitation is the use of simulated ground motions using various types of numerical techniques from physics-informed broadband stochastic approaches. Such simulations can generate predictions of strong ground motions in areas where certain events are deemed likely to occur, or are known to have occurred in the past, but before the advent and proliferation of ground motion recording instrumentation. The recognition of the importance of earthquake ground motion simulations is evident in the USGS’s collaboration with the NSF to jointly fund the SCEC—a significant contributor to the research on simulation of ground motions. The ERP has collaborated with the SCEC throughout the years to coordinate on projects to develop validation approaches for simulations with the goal of promoting using simulated ground motions in engineering practice.

A critical component of earthquake research is understanding how ground motions will affect infrastructure and human populations. A lack of observational data is a similar challenge for engineering researchers, but one that can also be addressed by using simulations. Earthquake engineers have long used numerical tools to simulate the response of structural and geotechnical systems to a wide range of earthquake ground motions, in practical settings (such as, nonlinear response history analysis of a single site or structure) and research applications (such as, large-scale parametric studies or regional-scale simulations). Research on strong ground motion simulations (Rezaeian and others, 2024), validation of already simulated motions, and use in engineering applications represents a growth opportunity for ERP because several personnel additions to the ERP have substantial prior experience and interest in numerical modeling. Potential efforts that could be established in the relative near-term include the following:

Given the opportunity for further expansion in staff, ERP can work on the following topics: Development of computational workflows and protocols internally for structural and geotechnical modeling using open-source simulation software (OpenSees, https://opensees.berkeley.edu/) and potential scalability to high-performance computing environments (for example, Amazon Web Services [AWS; https://aws.amazon.com/hpc/] and Natural Hazards Engineering Research Infrastructure [NEHRI] DesignSafe [https://www.designsafe-ci.org/]). Such efforts would expand earthquake engineering research capabilities in the following areas: