The Santa Cruz Mountains are closely associated with a left bend along the right‐lateral San Andreas fault. The Loma Prieta area on the northeast side of the San Andreas consists of fault‐bounded blocks that rise along active, deeply rooted, reverse and oblique‐slip faults. Six samples from a transect across this area yield concordant apatite fission track ages averaging 4.6±0.5 Ma. These ages date the time of cooling below ∼110°C and suggest that about 3 km of unroofing has occurred over the last 4.6 m.y. Allowing for current elevations of about 1 km, this suggests an average uplift rate of the order of 0.8 mm/yr over the last 4.6 m.y. To further define the extent and distribution of this young uplift, we used morphometric analyses of the youthful topography of the area. Steep drainage slopes and high local relief indicate that the area northeast of the San Andreas forms a well‐defined zone of high uplift. In contrast, the region on the southwest side of the San Andreas is characterized by broad upwarping and folding, more subdued topography, old fission track ages, and mean Quaternary uplift rates of 0.1–0.4 mm/yr. Geodetic data (1906 San Francisco earthquake and subsequent strain transients, 20 years of interseismic deformation, 1989 Loma Prieta earthquake, and 2 years of post‐Loma Prieta earthquake strain) show that the Southern Santa Cruz Mountains repeatedly rise and subside through a complex sequence of bay area deformation events. An additional deformation element that involves reverse slip averaging 2–3 mm/yr along the Foothills thrust system must occur to explain the longer‐term uplift pattern in the Loma Prieta area since the late Pliocene. The asymmetry in deformation on opposite sides of the San Andreas probably reflects the contrasting rock types on opposite sides of the fault, the influence of preexisting structures, and the interaction with neighboring faults of the San Andreas system.

In areas where regional tectonic strain is accommodated by broad zones of short and low slip rate faults, geomorphic and paleoseismic characterization of faults is difficult because of poor surface expression and long earthquake recurrence intervals. In humid areas, faults can be buried by thick sediments or soils; their geomorphic expression subdued and sometimes undetectable until the next earthquake. In Java, active faults are diffused, and their characterization is challenging. Among them is the ENE striking Cimandiri fault zone. Cumulative displacement produces prominent ENE oriented ranges with the southeast side moving relatively upward and to the northeast. The fault zone is expressed in the bedrock by numerous NE, west, and NW trending thrust‐ and strike‐slip faults and folds. However, it is unclear which of these structures are active. We performed a morphometric analysis of the fault zone using 30 m resolution Shuttle Radar Topography Mission digital elevation model. We constructed longitudinal profiles of 601 bedrock rivers along the upthrown ranges along the fault zone, calculated the normalized channel steepness index, identified knickpoints and use their distribution to infer relative magnitudes of rock uplift and locate boundaries that may indicate active fault traces. We compare the rock uplift distribution to surface displacement predicted by elastic dislocation model to determine the plausible fault kinematics. The active Cimandiri fault zone consists of six segments with predominant sense of reverse motion. Our analysis reveals considerable geometric complexity, strongly suggesting segmentation of the fault, and thus smaller maximum earthquakes, consistent with the limited historical record of upper plate earthquakes in Java.

Observations of surface deformation within 1–2 km of a surface rupture contain invaluable information about the coseismic behavior of the shallow crust. We investigate the oblique strike‐slip 2016 M7 Kumamoto, Japan, earthquake, which ruptured the Futagawa‐Hinagu Fault. We solve for variable fault slip in an inversion of differential lidar topography, satellite optical image correlation, and Interferometric Synthetic Aperture Radar (InSAR)‐derived surface displacements. The near‐fault differential lidar pose several challenges. The model fault geometry must follow the surface trace at the sub‐kilometer scale. Integration of displacement datasets with different sensitivities to the 3D deformation field and varying spatial distribution permits additional complexity in the inferred slip but introduces ambiguity that requires careful selection of the regularization. We infer a Mw 7.09−0.05+0.03 earthquake. The maximum slip of 6.9 m occurred at 4.5‐km depth, suggesting an on‐fault slip deficit in the upper several kilometers of the crust that likely reflects distributed and inelastic deformation within the shallow fault zone.

To define the seismic potential of the left-lateral strike-slip Alhama de Murcia fault (SE Iberian Peninsula), we calculated its slip rate by measuring offset linear features of known age using a morphotectonic analysis. The Lorca-Totana section of the fault yielded a minimum slip rate of 1.0 ± 0.2 mm/a for the past 30 ka, based on a channel whose age is estimated by OSL technique. The minimum left-lateral slip rate of the Goñar-Lorca section is 1.6-1.7 mm/a for the past 200 ka, based on eight offset surface channels, previously mapped alluvial fans dated by TL, and by new U-series dating of pedogenic carbonate. The U-series technique was used here for first time in the Iberian Peninsula to date small amounts (mg) of pedogenic carbonate. According to the newly estimated slip rate values, the Alhama de Murcia fault is one of the most active faults in the Eastern Betics Shear Zone. These values are larger and have fewer uncertainties in 1 comparison with previous slip rates estimations. In the Lorca-Totana section, the new lateral slip rate is compared with a slip rate calculated by means of a paleoseismic study showing good agreement between the values obtained with the two approaches.We encourage the combination of paleoseismology and morphotectonic analysis to obtain reliable slip rates for faults with scarce evidence of late Holocene slip.

We investigate the 4 April 2010 M w 7.2 El Mayor-Cucapah (Mexico) earthquake using three-dimensional surface deformation computed from preevent and postevent airborne lidar topography. By profiling the E-W, N-S, and vertical displacement fields at densely sampled (∼300 m) intervals along the multisegment rupture and computing fault offsets in each component, we map the slip vector along strike. Because the computed slip vectors must lie on the plane of the fault, whose local strike is known, we calculate how fault dip changes along the rupture. A principal goal is to resolve the discrepancy between field-based inferences of widespread low-angle (<30 ∘ ) oblique-normal slip beneath the Sierra Cucapah, and geodetic and/or seismological models which support steeper (50 ∘ -75 ∘ ) faulting in this area. Our results confirm that low-angle slip occurred along a short (∼2 km) stretch of the Paso Superior fault-where the three-dimensional rupture trace is also best fit by gently inclined planes-as well as along shorter (∼1 km) section of the Paso Inferior fault. We also characterize an ∼8-km fault crossing the Puerta accommodation zone as dipping ∼60 ∘ NE with slip of ∼2 m. These results indicate that within the northern Sierra Cucapah, deep-seated rupture of steep faults (resolved by coarse geodetic models) transfers at shallower depths onto low-angle structures. We also observe a statistically significant positive correlation between fault dip and slip, with slip pronounced along steep sections of fault and inhibited along low-angle sections. This highlights the important role of local structural fabric in controlling the surface expression of large earthquakes.