Project Grant G25AP00449

PROJECT TITLE: CONDITIONAL PROBABILITY OF DISTRIBUTED SURFACE RUPTURE USING THE FDHI DATABASEPROJECT PERIOD: 9 1 2025 THROUGH 8 31 2026AWARD PURPOSE: MANY CRITICAL AND IMPORTANT FACILITIES SUCH AS DAMS, POWERPLANTS, LANDFILLS, AND BUILDINGS INTHE US ARE LOCATED NEAR PRIMARY, ACTIVE FAULTS CAPABLE OF PRODUCING EARTHQUAKES OF ENGINEERING SIGNIFICANCE.THESE FACILITIES (GENERALLY SPEAKING) ARE DESIGNED TO PERFORM WELL FOR EXPECTED GROUND MOTIONS, BUT HAVE NOTBEEN DESIGNED FOR PERMANENT GROUND DEFORMATION DUE TO EARTHQUAKE SURFACE-FAULT RUPTURE. WITH A GROWINGNUMBER OF DETAILED POST-EARTHQUAKE FIELD SURVEYS, HOWEVER, THERE IS ABUNDANT EVIDENCE THAT SURFACE-FAULT RUPTUREON SECONDARY FAULTS AND SHEARS CAN EXTEND SEVERAL KILOMETERS FROM AN ACTIVE, PRIMARY FAULT. THIS HAS LED TO THERECOGNITION THAT THERE IS A NON-ZERO HAZARD OF SURFACE FAULT RUPTURE TO FACILITIES LOCATED NEAR PRIMARY, ACTIVEFAULTS, AND A NEWLY RECOGNIZED BUT UNCERTAIN RISK OF FAILURE FROM PERMANENT GROUND DISPLACEMENT. PROBABILISTICFAULT DISPLACEMENT HAZARD ANALYSIS IS A PREFERRED TOOL TO MEASURE THE HAZARD OF FAULT DISPLACEMENT FOR CRITICALAND IMPORTANT FACILITIES, AS IT CASTS THE HAZARD IN A FRAMEWORK SUITABLE FOR RISK ASSESSMENT AND PERFORMANCE BASED ENGINEERING EVALUATION. THIS PROJECT AIMS TO IMPROVE THE STANDARD OF PRACTICE FOR FAULT DISPLACEMENTHAZARD ANALYSIS BY DEVELOPING A NEW SET OF MODELS THAT ESTIMATE THE PROBABILITY OF SURFACE-FAULT RUPTURE AT A SITELOCATED OFF AN ACTIVE FAULT USING A RECENTLY RELEASED, EXPANDED DATABASE OF HISTORIC SURFACE-FAULT RUPTURES. ACTIVITIES TO BE PERFORMED: THE PROJECT WILL BUILD ON EXISTING METHODOLOGIES AND USES A SIGNIFICANTLY EXPANDEDDATABASE OF WELL-MAPPED HISTORIC SURFACE-FAULT RUPTURES AND AN EFFICIENT WORKFLOW USING GEOGRAPHICALINFORMATION SYSTEM (GIS) TOOLS. NO NEW PRIMARY DATA WILL BE COLLECTED AND NO FIELDWORK WILL BE PERFORMED.THE FIRST ACTIVITY IS COMPLETING THE DEVELOPMENT OF AN AUTOMATED GIS WORKFLOW USING AN INDUSTRY AND ACADEMIC STANDARD PLATFORM TO EFFICIENTLY PROCESS PUBLICLY-AVAILABLE SURFACE-FAULT RUPTURE TRACE DATA. THE RESULTINGPROCESSED DATA WILL BE EVALUATED TO DEVELOP STATISTICS ON THE PATTERNS AND FREQUENCY OF DISTRIBUTED FAULTING AWAYFROM PRINCIPAL RUPTURES. THESE RESULTS WILL BE FIT TO EQUATIONS TO PREDICT THE AVERAGE BEHAVIOR AND UNCERTAINTIESIN THE PROBABILITY OF A DISTRIBUTED RUPTURE WITH DISTANCE FROM A PRINCIPAL FAULT RUPTURE. COEFFICIENTS WILL BEDEVELOPED TO MODEL THE PROBABILITY OF DISTRIBUTED RUPTURE BASED ON FACTORS SUCH AS STYLE OF FAULTING, BUILDINGFOOTPRINT SIZE, AND HANGING WALL OR FOOTWALL LOCATION FOR DIPPING FAULTS.DELIVERABLES AND EXPECTED OUTCOMES: THE FINAL TECHNICAL REPORT WILL DOCUMENT THE OBJECTIVES, APPROACH, DATAINPUTS, AND MODEL RESULTS. RESULTS WILL CONSISTS OF EQUATION(S) EXPRESSING THE CONDITIONAL PROBABILITY OFDISTRIBUTED DISPLACEMENT FOR A SITE LOCATED AWAY FROM AN ACTIVE FAULT AND TABLES OF COEFFICIENTS TO BE USED WITHTHE EQUATIONS. UNCERTAINTIES IN THE RESULTS WILL BE CAPTURED IN THE FORM OF STANDARD DEVIATIONS OF SETS OFCOEFFICIENTS FOR DIFFERENT UNCERTAINTY PERCENTILES. ADDITIONAL ELECTRONIC DATA PRODUCTS WILL BE INCLUDED TO ALLOWUSERS TO INTERROGATE THE RESULTS AND DEVELOP ALTERNATIVE MODELS FOR USE IN SITE-SPECIFIC ANALYSES. WE WILL PUBLISHOUR FINDINGS IN A PEER-REVIEWED, OPEN-ACCESS JOURNAL AND PROVIDE ALL SUPPLEMENTAL DATA AND TOOLS AS OPEN-SOURCEPRODUCTS. INTENDED BENEFICIARIES: OWNERS AND STAKEHOLDERS OF CRITICAL AND IMPORTANT INFRASTRUCTURE SUCH AS DAMS, NUCLEAR POWER PLANTS, LANDFILLS, AND BUILDINGS LOCATED NEAR ACTIVE FAULTS THAT ARE VULNERABLE TO THE HAZARD OF SURFACE-FAULT DISPLACEMENT GEOSCIENTISTS AND ENGINEERS.SUBRECIPIENT ACTIVITIES: N A