This dataset provides simplified fault traces for the Gallina, Willow Creek, and West and East Brazos Peak fault systems in north-central New Mexico.

These datasets provide remotely mapped lineaments and neotectonic observations in northern New Mexico, based on 1-m lidar and satellite imagery data. Some lineaments are interpreted to be Quaternary-active faults, whereas others are interpreted to be older bedrock faults with no evidence for Quaternary movement. Simplified fault traces for interpreted Quaternary-active faults are provided for seismic hazard studies.

These datasets provide remotely mapped lineaments and neotectonic observations in northern New Mexico, based on 1-m lidar and satellite imagery data. Some lineaments are interpreted to be Quaternary-active faults, whereas others are interpreted to be older bedrock faults with no evidence for Quaternary movement. Simplified fault traces for interpreted Quaternary-active faults are provided for seismic hazard studies.

This data release contains a dataset that depicts fault scarps along the Zapata and Blanca sections of the Sangre de Cristo fault zone located in the San Luis basin of southern Colorado. The Zapata and Blanca sections extend from the Great Sand Dunes National Park and Preserve to the Blanca Peak massif and are differentiated by a sharp change in fault zone orientation from north-south to east-west. The fault scarps are the result of Quaternary tectonic extension causing surface rupturing earthquakes estimated to have occurred most recently 8-12 ka with probable Mw 6-7 (Ruleman and Machette, 2007). The dataset represents detailed mapping of probable fault surface rupture on high-resolution (1m/pix) topographic data from USGS 3DEP (U.S. Geological Survey, 2012; U.S. Geological Survey, 2021) mapped at 1:1400 scale. The mapping has been validated with GPS surveys at select locations along the fault zone. Primarily, mapping was conducted between September 2022 and December 2022 with subsequent updates and corrections. The data has undergone peer review but remains subject to revision as more information becomes available. The dataset is provided in shapefile KML, and geoJSON formats.

This data release contains a dataset that depicts fault scarps along the Zapata and Blanca sections of the Sangre de Cristo fault zone located in the San Luis basin of southern Colorado. The Zapata and Blanca sections extend from the Great Sand Dunes National Park and Preserve to the Blanca Peak massif and are differentiated by a sharp change in fault zone orientation from north-south to east-west. The fault scarps are the result of Quaternary tectonic extension causing surface rupturing earthquakes estimated to have occurred most recently 8-12 ka with probable Mw 6-7 (Ruleman and Machette, 2007). The dataset represents detailed mapping of probable fault surface rupture on high-resolution (1m/pix) topographic data from USGS 3DEP (U.S. Geological Survey, 2012; U.S. Geological Survey, 2021) mapped at 1:1400 scale. The mapping has been validated with GPS surveys at select locations along the fault zone. Primarily, mapping was conducted between September 2022 and December 2022 with subsequent updates and corrections. The data has undergone peer review but remains subject to revision as more information becomes available. The dataset is provided in shapefile KML, and geoJSON formats.

This release provides the data for a comprehensive survey of geologic structures in the eastern Española Basin of the Rio Grande rift, New Mexico. The release includes data and analyses from 53 individual fault zones and 22 other brittle structures, such as breccia zones, joints, and veins, investigated at a total of just over 100 sites. Structures were examined and compared from poorly lithified Tertiary sediments, as well as Paleozoic sedimentary and Proterozoic crystalline rocks. Data and analyses, include geologic maps; field observations and measurements; orientation, kinematic paleostress analyses and modeling; statistical examination of 575 fault trace lengths derived from aeromagnetic data in the Española and adjacent basins; mineralogy and chemistry of host and fault rocks; and investigation of fault versus bolide impact hypotheses for the origin of enigmatic breccias found in the Proterozoic basement rocks. Kinematic and paleostress analyses suggest a record of transitional, and perhaps partitioned, strains from the Laramide orogeny through Rio Grande rifting. Normal faults within Tertiary basin fill sediments are consistent with more typical WNW-ESE Rio Grande extension, perhaps decoupled from bedrock structures due to strength contrasts favoring the formation of new faults in the relatively weak sediments. Analyses of the fault length data indicate power law length distributions similar to those reported from many geologic settings globally. Mineralogy and chemistry in Proterozoic fault-related rocks reveal geochemical changes tied to hydrothermal alteration and nearly isochemical transformation of feldspars to clay minerals. In sediments, fault rocks are characterized by mechanical entrainment with minor secondary chemical changes. Enigmatic breccias are autoclastic, isochemical with respect to their protoliths, and occur near shatter cones believed to be related to a pre-Pennsylvanian impact event. A weak iridium anomaly is associated with the breccias as well as adjacent protoliths, thus an impact shock wave cannot be ruled out for their origin. The types of faults, associated brittle structures, and geochemical attributes provided here can aid in development of conceptual models and approaches useful in identifying testable hypotheses grounded in geological data when assessing ground- and surface-water resources.

This release provides the data for a comprehensive survey of geologic structures in the eastern Española Basin of the Rio Grande rift, New Mexico. The release includes data and analyses from 53 individual fault zones and 22 other brittle structures, such as breccia zones, joints, and veins, investigated at a total of just over 100 sites. Structures were examined and compared from poorly lithified Tertiary sediments, as well as Paleozoic sedimentary and Proterozoic crystalline rocks. Data and analyses, include geologic maps; field observations and measurements; orientation, kinematic paleostress analyses and modeling; statistical examination of 575 fault trace lengths derived from aeromagnetic data in the Española and adjacent basins; mineralogy and chemistry of host and fault rocks; and investigation of fault versus bolide impact hypotheses for the origin of enigmatic breccias found in the Proterozoic basement rocks. Kinematic and paleostress analyses suggest a record of transitional, and perhaps partitioned, strains from the Laramide orogeny through Rio Grande rifting. Normal faults within Tertiary basin fill sediments are consistent with more typical WNW-ESE Rio Grande extension, perhaps decoupled from bedrock structures due to strength contrasts favoring the formation of new faults in the relatively weak sediments. Analyses of the fault length data indicate power law length distributions similar to those reported from many geologic settings globally. Mineralogy and chemistry in Proterozoic fault-related rocks reveal geochemical changes tied to hydrothermal alteration and nearly isochemical transformation of feldspars to clay minerals. In sediments, fault rocks are characterized by mechanical entrainment with minor secondary chemical changes. Enigmatic breccias are autoclastic, isochemical with respect to their protoliths, and occur near shatter cones believed to be related to a pre-Pennsylvanian impact event. A weak iridium anomaly is associated with the breccias as well as adjacent protoliths, thus an impact shock wave cannot be ruled out for their origin. The types of faults, associated brittle structures, and geochemical attributes provided here can aid in development of conceptual models and approaches useful in identifying testable hypotheses grounded in geological data when assessing ground- and surface-water resources.

This Data Release contains preliminary versions of two related databases: 1) A fault sections database (“NSHM2023_FaultSections_v1”), which depicts the geometry of faults capable of hosting independent earthquakes, and 2) An earthquake geology site information database (“NSHM2023_EQGeoDB_v1”), which contains fault slip-rate constraints at points. These databases were prepared in anticipation of updates to the National Seismic Hazard Model (NSHM) 2023. Fault-specific geologic parameters for the NSHM have not been updated since the 2014 NSHM release. The datasets include the states of Washington, Oregon, California, Idaho, Nevada, Arizona, Montana, Wyoming, Colorado, New Mexico and Texas. Datasets containing fault information for Alaska and the Central and Eastern United States will be the subject of future efforts. These databases are provided as geospatial data (e.g., .SHP, .KML, .GeoJSON file formats) and tables (.CSV format).

This dataset is composed of linear active tectonic and other relevant features (scarps, deflected drainages, and lineaments and contrasts in topography, vegetation, and ground color) mapped based on high-resolution topography, aerial/satellite imagery, and field observations. The mapping covers the area surrounding the 2019 Ridgecrest, California earthquake surface ruptures. Point locations of field observations are also included.

This dataset is composed of linear active tectonic and other relevant features (scarps, deflected drainages, and lineaments and contrasts in topography, vegetation, and ground color) mapped based on high-resolution topography, aerial/satellite imagery, and field observations. The mapping covers the area surrounding the 2019 Ridgecrest, California earthquake surface ruptures. Point locations of field observations are also included.