A Mass Failure Model for the Initial Degradation of Fault Scarps, with Application to the 1959 Scarps at Hebgen Lake, Montana

Kogan, Lewis; Bendick, Rebecca

doi:10.1785/0120100107

Cited by 10 publications

(9 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similarly, many scarps, especially young scarps and scarps in cohesive material are subject to nondiffusive processes, such as slumping or gravitational collapse, that are not accounted for by the linear diffusion template. Models of scarp degradation incorporating gravitational collapse, such as Kogan and Bendick (), have been shown to provide more accurate morphologic age estimates in these cases, but these more sophisticated models cannot be used to derive a simple curvature template function.…”

Section: Discussionmentioning

confidence: 99%

“…This led to the deployment of “diffusion dating” of scarps to provide calibrated estimates of the time at which geomorphic features might have formed in the past. These methods have since been applied extensively to tectonic and nontectonic landforms, including normal fault scarps (Avouac & Peltzer, ; Enzel et al, ; Hanks, ; Hanks & Schwartz, ; Kogan & Bendick, ; Mattson & Bruhn, ), fault scarps resulting from strike‐slip motion (Arrowsmith et al, ; DeLong et al, ; Hilley et al, ), wave‐cut shorelines (Andrews & Bucknam, ; Hanks et al, ; Hanks & Wallace, ; Pelletier et al, ), alluvial terrace scarps (Clarke & Burbank, ; Pierce & Colman, ), and gullies on alluvial fan surfaces (Hsu & Pelletier, ).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Regional‐Scale Detection of Fault Scarps and Other Tectonic Landforms: Examples From Northern California

2019

View full text Add to dashboard Cite

Fault scarps and fault-related landforms provide important information about fault zone activity over timescales that are not captured by instrumental measurements or historic records. Semiautomated methods for delineating these landforms using topographic data from light detection and ranging (lidar) and spaceborne imaging systems offer the opportunity to characterize fault zones on a global scale. We present a computationally efficient method for extracting scarp-like landforms from high-resolution (≤ 2 m), regional-scale (≥ 100-km-long) digital topographic data sets. We identify fault-related landforms using a curvature template based on the diffusion model for scarp degradation and extract scarp heights and morphologic ages at each pixel. The method was applied to the GeoEarthScope Northern California data set, an airborne lidar acquisition imaging nearly 2,500 km 2 of the northern San Andreas Fault system, by adapting the algorithm to use cloud computing resources. Template results and fault trace mapping show spatial agreement in active fault zones with clear topographic expression, including detection of fault scarps, shutter ridges, and elongated drainages. Comparison of the method against field-based morphologic dating of scarps along the southern San Andreas reveals a trade-off between template window size and morphologic age contrasts resolved between strike-slip fault scarps of different relative ages. Detection performance suggests that window size and orientation constraints may play a key role in improving the accuracy of methods for semiautomated fault zone mapping. As data availability grows, these methods could constrain key earthquake simulation parameters such as damage zone width or rupture length and improve fault maps worldwide.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Regional‐Scale Detection of Fault Scarps and Other Tectonic Landforms: Examples From Northern California

2019

View full text Add to dashboard Cite

show abstract

“…Second, while 50 years elapsed between data collections, postseismic geodetic surveys collected immediately after the earthquake and again decades later rule out significant postseismic surface slip along the faults we investigate here (Nishimura & Thatcher, ). No recent afterslip has been observed by returning field geologists, and on the contrary, they have reported field and paleoseismic evidence of multiple events (e.g., Kogan & Bendick, ; Nash, ; Wallace, ; Zreda & Noller, ).…”

Section: Discussionmentioning

confidence: 99%

“…In many places, a small hangingwall depression or graben is preserved at the toe of the scarp, the remnants of fissuring caused by fault steepening in the near-surface (Witkind, 1964). Rarely we observe a small free face exceeding the angle of repose (∼40 ∘ ) preserved high up the scarp face, but eroded back from the original free face (Kogan & Bendick, 2011;Wallace, 1980). We look for evidence of composite scarps in the profiles and their derivatives, checking for the characteristic shapes outlined in Figure 4a, but rarely observing clear evidence of them.…”

Section: 1029/2017jb015039mentioning

confidence: 96%

Surface Rupture Morphology and Vertical Slip Distribution of the 1959M_w7.2 Hebgen Lake (Montana) Earthquake From Airborne Lidar Topography

2018

View full text Add to dashboard Cite

The 1959 Mw ∼7.2 Hebgen Lake earthquake is among the largest continental normal faulting events recorded, as well as one of the earliest associated with a multifault rupture. Multimeter vertical slip was observed on three main, morphologically distinct strands: the Hebgen fault and southeastern section of the Red Canyon fault, which both follow sharp topographic rangefronts, and the Red Canyon fault Kirkwood Ridge section, which cuts steep topography in the footwall of the Hebgen fault. We augment early field, seismological, and geodetic studies by investigating the modern surface rupture using newly acquired airborne lidar topography. By estimating throw from scarp profiling of the ∼36.5 km primary surface rupture, we show both that peak 1959 slip occurred at a structurally mature part of the fault and that many 1959 slip minima are associated with clear structural complexities. Vertical slip often substantially exceeds throw measured at the fault free face immediately after the earthquake; the scarps do not conclusively express beveled forms characteristic of repeated slip and degredation, yet must in places capture both the 1959 earthquake (for which we estimate an average throw of 2.64 m) and one or two preceding latest Pleistocene–Holocene events known from trenching. This has wider, cautionary implications for interpreting paleo‐earthquake chronologies and deriving magnitudes from morphologically simple scarps. By comparing 1959‐only and multievent vertical displacement populations, and considering preliminary paleoseismic data, we suggest that large surface‐rupturing earthquakes on the Hebgen and Red Canyon faults involve highly variable slip distributions.

show abstract

“…12). The time for this initial "mass-wasting" is uncertain, but estimates are 10 to 1000 years (Kogan and Bendick 2011). Important to the diffusion equation modeling of age is the time (τ0; years) required for the removal of the free face, and the initial mid-slope angle (θ0; degrees) at that time, which is commonly assumed to be the "angle of repose".…”

Section: Diffusion Model For Slope Degradationmentioning

confidence: 99%

Natural degradation of earthworks, trenches, walls and moats, Northern Thailand

Wood

Ziegler

2015

Journal of Field Archaeology

View full text Add to dashboard Cite

We investigate the geometry, age, and history of several enigmatic northern Thailand earthwork entrenchments that are mostly located on hills and could not have held water to form moats. The earthworks are either oval or rectangular in map view; and they typically encircle 0.3-to-1-km 2 areas that do not have potsherd debris indicative of former towns. Most trenches are 3-5 m deep with inner walls 4.5-8 m high. Some encircling earthworks are concentric double trenches spaced approximately 10 m apart. Historians have suggested these earthworks enclosed defensible areas where people in outlying villages sought refuge when under attack by neighboring rulers, the Chinese Ho, or the Burmese. We believe that some encircling entrenchments may have been for the capture or containment of elephants. Nearly all of the once near-vertical original walls have degraded to slopes of 32-47°. Fitting calculated curves of the diffusion-based scarp-degradation model to our height-slope data, and assuming most scarps have degraded since the end of La Na Kingdom time A.D. 1558. We derive a diffusion coefficient of 0.002 m 2 y -1 . Slopes of the rectangular earthwork at Souvannkhomkham, Laos, across the Mekong River from Chiang Saen Noi, are significantly more degraded (approximately 32°), indicating an age of 800-1200 years. Locations of these earthworks are established in hope that they will be preserved as part of the Thai and Lao archaeological legacy.

show abstract

A Mass Failure Model for the Initial Degradation of Fault Scarps, with Application to the 1959 Scarps at Hebgen Lake, Montana

Cited by 10 publications

References 37 publications

Regional‐Scale Detection of Fault Scarps and Other Tectonic Landforms: Examples From Northern California

Regional‐Scale Detection of Fault Scarps and Other Tectonic Landforms: Examples From Northern California

Surface Rupture Morphology and Vertical Slip Distribution of the 1959M_w7.2 Hebgen Lake (Montana) Earthquake From Airborne Lidar Topography

Natural degradation of earthworks, trenches, walls and moats, Northern Thailand

Contact Info

Product

Resources

About

A Mass Failure Model for the Initial Degradation of Fault Scarps, with Application to the 1959 Scarps at Hebgen Lake, Montana

Cited by 10 publications

References 37 publications

Regional‐Scale Detection of Fault Scarps and Other Tectonic Landforms: Examples From Northern California

Regional‐Scale Detection of Fault Scarps and Other Tectonic Landforms: Examples From Northern California

Surface Rupture Morphology and Vertical Slip Distribution of the 1959Mw7.2 Hebgen Lake (Montana) Earthquake From Airborne Lidar Topography

Natural degradation of earthworks, trenches, walls and moats, Northern Thailand

Contact Info

Product

Resources

About

Surface Rupture Morphology and Vertical Slip Distribution of the 1959M_w7.2 Hebgen Lake (Montana) Earthquake From Airborne Lidar Topography