Holocene Paleoseismology of the Steamboat Mountain Site: Evidence for Full-Length Rupture of the Teton Fault, Wyoming

ABSTRACT The 72-km-long Teton fault in northwestern Wyoming is an ideal candidate for reconstructing the lateral extent of surface-rupturing earthquakes and testing models of normal-fault segmentation. To explore the history of earthquakes on the northern Teton fault, we hand-excavated two trenches at the Steamboat Mountain site, where the east-dipping Teton fault has vertically displaced west-sloping alluvial-fan surfaces. The trenches exposed glaciofluvial, alluvial-fan, and scarp-derived colluvial sediments and stratigraphic and structural evidence of two surface-rupturing earthquakes (SM1 and SM2). A Bayesian geochronologic model for the site includes three optically stimulated luminescence ages (∼12–17 ka) for the glaciofluvial units and 16 radiocarbon ages (∼1.2–8.6 ka) for the alluvial-fan and colluvial units and constrains SM1 and SM2 to 5.5±0.2 ka, 1σ (5.2–5.9 ka, 95%) and 9.7±0.9 ka, 1σ (8.5–11.5 ka, 95%), respectively. Structural, stratigraphic, and geomorphic relations yield vertical displacements for SM1 (2.0±0.6 m, 1σ) and SM2 (2.0±1.0 m, 1σ). The Steamboat Mountain paleoseismic chronology overlaps temporally with earthquakes interpreted from previous terrestrial and lacustrine paleoseismic data along the fault. Integrating these data, we infer that the youngest Teton fault rupture occurred at ∼5.3 ka, generated 1.7±1.0 m, 1σ of vertical displacement along 51–70 km of the fault, and had a moment magnitude (Mw) of ∼7.0–7.2. This rupture was apparently unimpeded by structural complexities along the Teton fault. The integrated chronology permits a previous full-length rupture at ∼10 ka and possible partial ruptures of the fault at ∼8–9 ka. To reconcile conflicting terrestrial and lacustrine paleoseismic data, we propose a hypothesis of alternating full- and partial-length ruptures of the Teton fault, including Mw∼6.5–7.2 earthquakes every ∼1.2 ky. Additional paleoseismic data for the northern and central sections of the fault would serve to test this bimodal rupture hypothesis.

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Variable normal-fault rupture behavior, northern Lost River fault zone, Idaho, USA

Geosphere ◽

10.1130/ges02096.1 ◽

2019 ◽

Vol 15 (6) ◽

pp. 1869-1892 ◽

Cited By ~ 3

Author(s):

Christopher B. DuRoss ◽

Michael P. Bunds ◽

Ryan D. Gold ◽

Richard W. Briggs ◽

Nadine G. Reitman ◽

...

Keyword(s):

Fault Zone ◽

Structural Complexity ◽

Normal Fault ◽

Vertical Displacement ◽

Fault Rupture ◽

Surface Displacements ◽

Surface Models ◽

History Of ◽

Warm Springs ◽

The Moment

Abstract The 1983 Mw 6.9 Borah Peak earthquake generated ∼36 km of surface rupture along the Thousand Springs and Warm Springs sections of the Lost River fault zone (LRFZ, Idaho, USA). Although the rupture is a well-studied example of multisegment surface faulting, ambiguity remains regarding the degree to which a bedrock ridge and branch fault at the Willow Creek Hills influenced rupture progress. To explore the 1983 rupture in the context of the structural complexity, we reconstruct the spatial distribution of surface displacements for the northern 16 km of the 1983 rupture and prehistoric ruptures in the same reach of the LRFZ using 252 vertical-separation measurements made from high-resolution (5–10-cm-pixel) digital surface models. Our results suggest the 1983 Warm Springs rupture had an average vertical displacement of ∼0.3–0.4 m and released ∼6% of the seismic moment estimated for the Borah Peak earthquake and <12% of the moment accumulated on the Warm Springs section since its last prehistoric earthquake. The 1983 Warm Springs rupture is best described as the moderate-displacement continuation of primary rupture from the Thousand Springs section into and through a zone of structural complexity. Historical and prehistoric displacements show that the Willow Creek Hills have impeded some, but not all ruptures. We speculate that rupture termination or penetration is controlled by the history of LRFZ moment release, displacement, and rupture direction. Our results inform the interpretation of paleoseismic data from near zones of normal-fault structural complexity and demonstrate that these zones may modulate rather than impede rupture displacement.

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Seismic Activity of the Manisa Fault Zone in Western Turkey Constrained by Cosmogenic 36Cl Dating

Geosciences ◽

10.3390/geosciences11110451 ◽

2021 ◽

Vol 11 (11) ◽

pp. 451

Author(s):

Nasim Mozafari ◽

Çağlar Özkaymak ◽

Dmitry Tikhomirov ◽

Susan Ivy-Ochs ◽

Vasily Alfimov ◽

...

Keyword(s):

Fault Zone ◽

Normal Fault ◽

Vertical Displacement ◽

Historical Records ◽

Western Turkey ◽

Slip Rates ◽

Vertical Displacements ◽

Surface Ruptures ◽

Fault Scarps ◽

Calculated Average

This study reports on the cosmogenic 36Cl dating of two normal fault scarps in western Turkey, that of the Manastır and Mugırtepe faults, beyond existing historical records. These faults are elements of the western Manisa Fault Zone (MFZ) in the seismically active Gediz Graben. Our modeling revealed that the Manastır fault underwent at least two surface ruptures at 3.5 ± 0.9 ka and 2.0 ± 0.5 ka, with vertical displacements of 3.3 ± 0.5 m and 3.6 ± 0.5 m, respectively. An event at 6.5 ± 1.6 ka with a vertical displacement of 2.7 ± 0.4 m was reconstructed on the Mugırtepe fault. We attribute these earthquakes to the recurring MFZ ruptures, when also the investigated faults slipped. We calculated average slip rates of 1.9 and 0.3 mm yr−1 for the Manastır and Mugırtepe faults, respectively.

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Late Holocene landscape change history related to the Alpine Fault determined from drowned forests in Lake Poerua, Westland, New Zealand

Natural Hazards and Earth System Science ◽

10.5194/nhess-12-2051-2012 ◽

2012 ◽

Vol 12 (6) ◽

pp. 2051-2064 ◽

Cited By ~ 8

Author(s):

R. M. Langridge ◽

R. Basili ◽

L. Basher ◽

A. P. Wells

Keyword(s):

Lake Level ◽

Late Holocene ◽

Alluvial Fan ◽

Time Of Death ◽

Fault Rupture ◽

Radiocarbon Dates ◽

Living Tree ◽

Alpine Fault ◽

History Of ◽

Lowland Forests

Abstract. Lake Poerua is a small, shallow lake that abuts the scarp of the Alpine Fault on the West Coast of New Zealand's South Island. Radiocarbon dates from drowned podocarp trees on the lake floor, a sediment core from a rangefront alluvial fan, and living tree ring ages have been used to deduce the late Holocene history of the lake. Remnant drowned stumps of kahikatea (Dacrycarpus dacrydioides) at 1.7–1.9 m water depth yield a preferred time-of-death age at 1766–1807 AD, while a dryland podocarp and kahikatea stumps at 2.4–2.6 m yield preferred time-of-death ages of ca. 1459–1626 AD. These age ranges are matched to, but offset from, the timings of Alpine Fault rupture events at ca. 1717 AD, and either ca. 1615 or 1430 AD. Alluvial fan detritus dated from a core into the toe of a rangefront alluvial fan, at an equivalent depth to the maximum depth of the modern lake (6.7 m), yields a calibrated age of AD 1223–1413. This age is similar to the timing of an earlier Alpine Fault rupture event at ca. 1230 AD ± 50 yr. Kahikatea trees growing on rangefront fans give ages of up to 270 yr, which is consistent with alluvial fan aggradation following the 1717 AD earthquake. The elevation levels of the lake and fan imply a causal and chronological link between lake-level rise and Alpine Fault rupture. The results of this study suggest that the growth of large, coalescing alluvial fans (Dry and Evans Creek fans) originating from landslides within the rangefront of the Alpine Fault and the rise in the level of Lake Poerua may occur within a decade or so of large Alpine Fault earthquakes that rupture adjacent to this area. These rises have in turn drowned lowland forests that fringed the lake. Radiocarbon chronologies built using OxCal show that a series of massive landscape changes beginning with fault rupture, followed by landsliding, fan sedimentation and lake expansion. However, drowned Kahikatea trees may be poor candidates for intimately dating these events, as they may be able to tolerate water for several decades after metre-scale lake level rises have occurred.

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Centrifuge modeling of normal faulting and underground tunnel in sandy soil deposit

Soils and Rocks ◽

10.28927/sr.2021.059520 ◽

2021 ◽

Vol 44 (2) ◽

pp. 1-13

Author(s):

Ali Nabizadeh ◽

Alireza Seghateh Mojtahedi

Keyword(s):

Free Field ◽

Soil Layer ◽

Ground Surface ◽

Normal Fault ◽

Vertical Displacement ◽

Centrifuge Modeling ◽

Fault Rupture ◽

Normal Faulting ◽

Axis Parallel ◽

Propagation Pattern

Earthquakes of large magnitudes cause fault ruptures propagation in soil layers and lead to interactions with subsurface and surface structures. The emergence of fault ruptures on or adjacent to the position of existing tunnels cause significant damage to the tunnels. The objective of this paper is to study the interaction of an embedded tunnel within a soil layer and the soil deformations imposed upon by normal faulting. A centrifuge modeling under 80-g acceleration was conducted to investigate the rupture propagation pattern for different relative tunnel positions. Compared with the free field condition, due to tunnel and normal fault rupture interactions, focused on soil relative density and tunnel rigidity in this research, found that they can dramatically modify the rupture path depending on the tunnel position relative to the fault tip. The tunnel diverts the rupture path to its sides. This study presents the normal fault-tunnel interaction with the tunnel axis parallel to the normal fault line, to examine the changes that take place in fault rupture plane locations, the vertical displacement of the ground surface with tunnel presence and the effect of tunnel rigidity and soil density on fault tunnel interaction.

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Holocene earthquake history and slip rate of the southern Teton fault, Wyoming, USA

Geological Society of America Bulletin ◽

10.1130/b35363.1 ◽

2019 ◽

Vol 132 (7-8) ◽

pp. 1566-1586 ◽

Cited By ~ 3

Author(s):

Christopher B. DuRoss ◽

Ryan D. Gold ◽

Richard W. Briggs ◽

Jaime E. Delano ◽

Dean A. Ostenaa ◽

...

Keyword(s):

Slip Rate ◽

Normal Fault ◽

Alluvial Fan ◽

Early Holocene ◽

Data Sets ◽

History Of ◽

Teton Range ◽

Geomorphic Surfaces ◽

Fault Record ◽

Earthquake Cycles

Abstract The 72-km-long Teton normal fault bounds the eastern base of the Teton Range in northwestern Wyoming, USA. Although geomorphic surfaces along the fault record latest Pleistocene to Holocene fault movement, the postglacial earthquake history of the fault has remained enigmatic. We excavated a paleoseismic trench at the Buffalo Bowl site along the southernmost part of the fault to determine its Holocene rupture history and slip rate. At the site, ∼6.3 m of displacement postdates an early Holocene (ca. 10.5 ka) alluvial-fan surface. We document evidence of three surface-faulting earthquakes based on packages of scarp-derived colluvium that postdate the alluvial-fan units. Bayesian modeling of radiocarbon and luminescence ages yields earthquake times of ca. 9.9 ka, ca. 7.1 ka, and ca. 4.6 ka, forming the longest, most complete paleoseismic record of the Teton fault. We integrate these data with a displaced deglacial surface 4 km NE at Granite Canyon to calculate a postglacial to mid-Holocene (14.4–4.6 ka) slip rate of ∼1.1 mm/yr. Our analysis also suggests that the postglacial to early Holocene (14.4–9.9 ka) slip rate exceeds the Holocene (9.9–4.6 ka) rate by a factor of ∼2 (maximum of 3); however, a uniform rate for the fault is possible considering the 95% slip-rate errors. The ∼5 k.y. elapsed time since the last rupture of the southernmost Teton fault implies a current slip deficit of ∼4–5 m, which is possibly explained by spatially/temporally incomplete paleoseismic data, irregular earthquake recurrence, and/or variable per-event displacement. Our study emphasizes the importance of minimizing slip-rate uncertainties by integrating paleoseismic and geomorphic data sets and capturing multiple earthquake cycles.

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The Earl, the Kings, and the Chronicler

10.1093/oso/9780198797814.001.0001 ◽

2019 ◽

Author(s):

Robert B. Patterson

Keyword(s):

Civil War ◽

Twelfth Century ◽

Full Length ◽

English History ◽

Cultural Revival ◽

South Wales ◽

Anglo Norman ◽

Merchant Class ◽

History Of ◽

William The Conqueror

This book is the first full length biography of Robert (c.1088 × 90–1147), grandson of William the Conqueror and eldest son of King Henry I of England (1100–35). He could not succeed his father because he was a bastard. Instead, as the earl of Gloucester, Robert helped change the course of English history by keeping alive the prospects for an Angevin succession through his leadership of its supporters in the civil war known as the Anarchy against his father’s successor, King Stephen (1135–54). The earl is one of the great figures of Anglo-Norman History (1066–1154). He was one of only three landed super-magnates of his day, a model post-Conquest great baron, Marcher lord, borough developer, and patron of the rising merchant class. His trans-Channel barony stretched from western Lower Normandy across England to South Wales. He was both product as well as agent of the contemporary cultural revival known as the Renaissance of the Twelfth Century, bilingual, well educated, and a significant literary patron. In this last role, he is especially notable for commissioning the greatest English historian since Bede, William of Malmesbury, to produce a history of their times which justified the Empress Matilda’s claim to the English throne and Earl Robert’s support of it.

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Centrifuge and numerical modelling of tunnel intersected by normal fault rupture in sand

Computers and Geotechnics ◽

10.1016/j.compgeo.2019.03.010 ◽

2019 ◽

Vol 111 ◽

pp. 137-146 ◽

Cited By ~ 5

Author(s):

Q.P. Cai ◽

J.M. Peng ◽

Charles. W.W. Ng ◽

J.W. Shi ◽

X.X. Chen

Keyword(s):

Numerical Modelling ◽

Normal Fault ◽

Fault Rupture

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The Concept of Accuracy Analysis of the Vertical Displacements Gained from the Hydrostatic Levelling Systems’ Measurements

Sensors ◽

10.3390/s21144842 ◽

2021 ◽

Vol 21 (14) ◽

pp. 4842

Author(s):

Waldemar Kamiński

Keyword(s):

Accuracy Assessment ◽

Theoretical Models ◽

Vertical Displacement ◽

Serial Connection ◽

Vertical Displacements ◽

Comprehensive Determination ◽

The One ◽

The Individual ◽

Reference Sensor

Nowadays, hydrostatic levelling is a widely used method for the vertical displacements’ determinations of objects such as bridges, viaducts, wharfs, tunnels, high buildings, historical buildings, special engineering objects (e.g., synchrotron), sports and entertainment halls. The measurements’ sensors implemented in the hydrostatic levelling systems (HLSs) consist of the reference sensor (RS) and sensors located on the controlled points (CPs). The reference sensor is the one that is placed at the point that (in theoretical assumptions) is not a subject to vertical displacements and the displacements of controlled points are determined according to its height. The hydrostatic levelling rule comes from the Bernoulli’s law. While using the Bernoulli’s principle in hydrostatic levelling, the following components have to be taken into account: atmospheric pressure, force of gravity, density of liquid used in sensors places at CPs. The parameters mentioned above are determined with some mean errors that influence on the accuracy assessment of vertical displacements. In the subject’s literature, there are some works describing the individual accuracy analyses of the components mentioned above. In this paper, the author proposes the concept of comprehensive determination of mean error of vertical displacement (of each CPs), calculated from the mean errors’ values of components dedicated for specific HLS. The formulas of covariances’ matrix were derived and they enable to make the accuracy assessment of the calculations’ results. The author also presented the subject of modelling of vertical displacements’ gained values. The dependences, enabling to conduct the statistic tests of received model’s parameters, were implemented. The conducted tests make it possible to verify the correctness of used theoretical models of the examined object treated as the rigid body. The practical analyses were conducted for two simulated variants of sensors’ connections in HLS. Variant no. I is the sensors’ serial connection. Variant no. II relies on the connection of each CPs with the reference sensor. The calculations’ results show that more detailed value estimations of the vertical displacements can be obtained using variant no. II.

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Concurrence of 1- and 3-Min Sit-to-Stand Tests with the 6-Min Walk Test in Idiopathic Pulmonary Fibrosis

Respiration ◽

10.1159/000515335 ◽

2021 ◽

pp. 1-9

Author(s):

Arnaud Fedi ◽

Sophia Keddache ◽

Sébastien Quétant ◽

Alicia Guillien ◽

Anestis Antoniadis ◽

...

Keyword(s):

Idiopathic Pulmonary Fibrosis ◽

Pulmonary Fibrosis ◽

Daily Practice ◽

Vertical Displacement ◽

Physiological Parameters ◽

Walk Test ◽

Prognostic Information ◽

Exercise Tests ◽

Sit To Stand ◽

Vertical Displacements

Background: In idiopathic pulmonary fibrosis (IPF), some physiological parameters measured during a 6-min walk test (6-MWT) impart reliable prognostic information. Sit-to-stand tests (STSTs) are field exercise tests that are easier to implement than the 6-MWT in daily practice. Objectives: The aims of the study were to test the reproducibility and compare 2 STSTs (the 1-min STST [1-STST] and the semi-paced 3-min chair rise test [3-CRT]) in IPF, and to determine if selected physiological parameters (speed of displacement and changes in pulse oxygen saturation [SpO2]) are interchangeable between the STSTs and the 6-MWT. Methods: Thirty-three patients with stable IPF were studied in 3 French expert centers. To test reproducibility, intra-class correlations (ICCs) of parameters measured during tests performed 7–14 days apart were calculated. To test interchangeability, the agreement and correlation of physiological responses measured during STSTs and during 6-MWT were studied. Results: Vertical displacements and changes in SpO2 during both STSTs were reproducible, with ICCs ranging from 0.78 [0.63–0.87] to 0.95 [0.92–0.97]. Vertical displacements during 1-STST and 3-CRT were correlated with 6-MWT distance (correlation coefficients (r) of 0.72 and 0.77, respectively; p < 0.001). Similarly, correlations were found between changes in SpO2 measured during the 2 STSTs and the 6-MWT, with coefficients ranging from 0.73 to 0.91 (p < 0.001). Distance walked and SpO2 during 6-MWT were well estimated from vertical displacement and SpO2 during the 2 STSTs, respectively. Conclusion: The correlations found between the 2 STSTs and the 6-MWT suggest that STSTs may be of interest to assess displacement and exercise-induced changes in SpO2 in IPF patients.

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