Neotectonic and Paleoseismic Analysis of the Northwest Extent of Holocene Surface Deformation along the Meers Fault, Oklahoma

Kristofer T. Hornsby; Ashley R. Streig; Scott E. K. Bennett; Jefferson C. Chang; Shannon Mahan

doi:10.1785/0120180148

Neotectonic and Paleoseismic Analysis of the Northwest Extent of Holocene Surface Deformation along the Meers Fault, Oklahoma

Bulletin of the Seismological Society of America ◽

10.1785/0120180148 ◽

2019 ◽

Vol 110 (1) ◽

pp. 49-66 ◽

Cited By ~ 1

Author(s):

Kristofer T. Hornsby ◽

Ashley R. Streig ◽

Scott E. K. Bennett ◽

Jefferson C. Chang ◽

Shannon Mahan

Keyword(s):

Surface Deformation ◽

Seismic Source ◽

Complex Surface ◽

Surface Expression ◽

Fault Scarp ◽

Source Characterization ◽

Surface Rupture ◽

Alluvial Deposits ◽

Aerial Photos ◽

Stable Continental Region

ABSTRACT The Meers fault (Oklahoma) is one of few seismogenic structures with evidence for Holocene surface rupture in the stable continental region of North America. The 37-kilometer-long southeast section of the full 54-kilometer-long Meers fault is interpreted to be Holocene active. The 17-kilometer-long northwest section is considered Quaternary active, but not Holocene active. We reevaluate surface expression and earthquake timing of the northwest Meers fault to improve seismic source characterization. We use airborne light detection and ranging and historical stereopaired aerial photos to evaluate the fault scarp and local fault-zone geomorphology. In the northwest, complex surface deformation includes fault splays, subtle monoclinal warping, and a minor change in fault strike. We interpret that the along-strike transition from surface faulting on the southeast Meers fault to surface folding on the northwest Meers fault occurs at the lithologic contact between Permian Post Oak conglomerate and Hennessey shale. We excavated a paleoseismic trench to evaluate the timing of surface-deforming earthquakes on the northwest section of the fault. The excavation revealed weathered Permian Hennessey shale and an ∼1–2-meter-thick veneer of Holocene alluvial deposits that were progressively deformed during two surface-folding earthquakes likely related to blind fault rupture beneath the site. Repeated onlapping to overlapping stratigraphic sequences and associated unconformities are intimately related to folding events along the monocline. OxCal paleoearthquake age modeling indicates that earthquakes occurred 4704–3109 yr B.P. and 5955–4744 yr B.P., and that part of the northwest section of the Meers fault is Holocene active. We find the Holocene-active section of the Meers fault should be lengthened 6.1 km to the northwest, to a total Holocene-active fault length of 43 km. Empirical scaling relationships between surface rupture length and magnitude reveal that the fault could generate an Mw 7.0 earthquake.

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Neogene-Quaternary tectonic regime and macroseismic observations in the Tyrnavos-Elassona broader epicentral area of the March 2021, intense earthquake sequence

Bulletin of the Geological Society of Greece ◽

10.12681/bgsg.27196 ◽

2021 ◽

Vol 58 ◽

pp. 200

Author(s):

Dimitrios Galanakis ◽

Sotiris Sboras ◽

Garyfalia Konstantopoulou ◽

Markos Xenakis

Keyword(s):

Normal Fault ◽

Fault Scarp ◽

Focal Mechanisms ◽

Fault System ◽

Spatiotemporal Evolution ◽

Surface Rupture ◽

Alluvial Deposits ◽

Epicentral Area ◽

Ground Shaking ◽

Macroseismic Observations

On March 3, 2021, a strong (Mw6.3) earthquake occurred near the towns of Tyrnavos and Elassona. One day later (March 4), a second strong (Mw6.0) earthquake occurred just a few kilometres toward the WNW. The aftershock spatial distribution and the focal mechanisms revealed NW-SE-striking normal faulting. The focal mechanisms also revealed a NE-SW oriented extensional stress field, different from the orientation we knew so far (ca. N-S). The magnitude and location of the two strongest shocks, and the spatiotemporal evolution of the sequence, strongly suggest that two adjacent fault segments were ruptured respectively. The sequence was followed by several coseismic ground deformational phenomena, such as landslides/rockfalls, liquefaction and ruptures. The landslides and rockfalls were mostly associated with the ground shaking. The ruptures were observed west of the Titarissios River, near to the Quaternary faults found by bore-hole lignite investigation. In the same direction, a fault scarp separating the alpidic basement from the alluvial deposits of the Titarissios valley implies the occurrence of a well-developed fault system. Some of the ground ruptures were accompanied by extensive liquefaction phenomena. Others cross-cut reinforced concrete irrigation channels without changing their direction. We suggest that this fault system was partially reactivated, as a secondary surface rupture, during the sequence as a steeper splay of a deeper low-to-moderate angle normal fault.

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The 2018 Lake Muir earthquake sequence, southwest Western Australia: rethinking Australian stable continental region earthquakes

10.5194/se-2019-125 ◽

2019 ◽

Cited By ~ 2

Author(s):

Dan J. Clark ◽

Sarah Brennand ◽

Gregory Brenn ◽

Trevor I. Allen ◽

Matthew C. Garthwaite ◽

...

Keyword(s):

Western Australia ◽

Surface Deformation ◽

Vertical Displacement ◽

Strike Slip ◽

Double Difference ◽

Surface Rupture ◽

Field Mapping ◽

Scaling Relationships ◽

Magnitude Scaling ◽

Stable Continental Region

Abstract. Modern geodetic and seismic monitoring tools are enabling the study of moderate-sized earthquake sequences in unprecedented detail. Here we use a variety of methods to examine surface deformation caused by a sequence of earthquakes near Lake Muir in southwest Western Australia in 2018. A shallow MW 5.3 earthquake on the 16th of September 2018 was followed on the 8th of November 2018 by a MW 5.2 event in the same region. Focal mechanisms for the events suggest reverse and strike-slip rupture, respectively. Interferometric Synthetic Aperture Radar (InSAR) analysis of the events suggests that the ruptures are in part spatially coincident. Field mapping, guided by the InSAR results, reveals that the first event produced an approximately 3 km long and up to 0.5 m high west-facing surface rupture, consistent with slip on a moderately east-dipping fault. Double difference hypocentre relocation of aftershocks using data from rapidly deployed seismic instrumentation confirms an east-dipping rupture plane for the first event, and shows a concentration located at the northern end of the rupture where the InSAR suggests greatest vertical displacement. The November event resulted from rupture on a northeast-trending strike-slip fault. UAV-derived digital terrain models (differenced with pre-event LiDAR) reveal a surface deformation envelope consistent with the InSAR for the first event, but could not discern deformation unique to the second event. New rupture length versus magnitude scaling relationships developed for non-extended cratonic regions as part of this study allow for the distinction between “visible” surface rupture lengths (VSRL) from field-mapping and “detectable” surface rupture lengths (DSRL) from remote sensing techniques such as InSAR, and suggest longer ruptures for a given magnitude than implied by commonly used scaling relationships.

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Surface deformation relating to the 2018 Lake Muir earthquake sequence, southwest Western Australia: new insight into stable continental region earthquakes

Solid Earth ◽

10.5194/se-11-691-2020 ◽

2020 ◽

Vol 11 (2) ◽

pp. 691-717 ◽

Cited By ~ 2

Author(s):

Dan J. Clark ◽

Sarah Brennand ◽

Gregory Brenn ◽

Matthew C. Garthwaite ◽

Jesse Dimech ◽

...

Keyword(s):

Western Australia ◽

Surface Deformation ◽

Earthquake Sequence ◽

Historical Event ◽

Surface Rupture ◽

Temporal Relationships ◽

Stable Continental Region ◽

Discrete Surface ◽

Historical Times ◽

Earthquake Sequences

Abstract. A shallow Mw 5.3 earthquake near Lake Muir in the stable continental region (SCR) crust of southwest Western Australia on the 16 September 2018 was followed on the 8 November by a proximal Mw 5.2 event. Focal mechanisms produced for the events suggest reverse and strike-slip rupture, respectively. Field mapping, guided by Sentinel-1 InSAR data, reveals that the first event produced an approximately 3 km long and up to 0.4–0.6 m high west-facing surface rupture, consistent with reverse slip on a moderately east-dipping fault. The InSAR data also show that the surface scarp relates to a subsurface rupture ∼ 5 km long, bound at its northern and southern extremities by bedrock structures. The November event produced a surface deformation envelope that is spatially coincident with that of the September event but did not result in discrete surface rupture. Almost 900 aftershocks were recorded by a temporary seismometer deployment. Hypocentre locations correlate poorly with the rupture plane of their respective mainshocks but correlate well with regions of increased Coulomb stress. The spatial and temporal relationships between the Mw>5.0 events and their aftershocks reveals dependencies with implications for how other less well-documented SCR earthquake sequences could be interpreted. Furthermore, the September Mw 5.3 Lake Muir earthquake was the ninth event documented to have produced surface rupture in Australia in historical times. These nine ruptures are located exclusively in the Precambrian non-extended SCR rocks of central and western Australia, and none could have been identified and mapped using topographic signature prior to the historical event. Consistent, though fragmentary, evidence exists from analogous regions worldwide. Our analysis of the Lake Muir earthquake sequence therefore provides constraint on models describing mechanisms for strain accumulation and localized release as earthquakes in non-extended SRC crust.

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Progressive Degradation of an Ice Rumple in the Thwaites Ice Shelf, Antarctica, as Observed from High-Resolution Digital Elevation Models

Remote Sensing ◽

10.3390/rs10081236 ◽

2018 ◽

Vol 10 (8) ◽

pp. 1236 ◽

Cited By ~ 1

Author(s):

Seung Hee Kim ◽

Duk-jin Kim ◽

Hyun-Cheol Kim

Keyword(s):

High Resolution ◽

Surface Deformation ◽

Surface Expression ◽

Deformation Model ◽

Ice Shelf ◽

Pressure Source ◽

Viscoelastic Deformation ◽

Shelf Stability ◽

Transient Nature ◽

Elevation Changes

Ice rumples are locally-grounded features of flowing ice shelves, elevated tens of meters above the surrounding surface. These features may significantly impact the dynamics of ice-shelf grounding lines, which are strongly related to shelf stability. In this study, we used TanDEM-X data to construct high-resolution DEMs of the Thwaites ice shelf in West Antarctica from 2011 to 2013. We also generated surface deformation maps which allowed us to detect and monitor the elevation changes of an ice rumple that appeared sometime between the observations of a grounding line of the Thwaites glacier using Double-Differential Interferometric SAR (DDInSAR) in 1996 and 2011. The observed degradation of the ice rumple during 2011–2013 may be related to a loss of contact with the underlying bathymetry caused by the thinning of the ice shelf. We subsequently used a viscoelastic deformation model with a finite spherical pressure source to reproduce the surface expression of the ice rumple. Global optimization allowed us to fit the model to the observed deformation map, producing reasonable estimates of the ice thickness at the center of the pressure source. Our conclusion is that combining the use of multiple high-resolution DEMs and the simple viscoelastic deformation model is feasible for observing and understanding the transient nature of small ice rumples, with implications for monitoring ice shelf stability.

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BSHAP seismic source characterization models for the Western Balkan region

Bulletin of Earthquake Engineering ◽

10.1007/s10518-017-0143-5 ◽

2017 ◽

Vol 15 (10) ◽

pp. 3963-3985 ◽

Cited By ~ 4

Author(s):

Jadranka Mihaljević ◽

Polona Zupančič ◽

Neki Kuka ◽

Nataša Kaluđerović ◽

Rexhep Koçi ◽

...

Keyword(s):

Seismic Source ◽

Source Characterization ◽

Western Balkan Region ◽

Balkan Region

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Seismic Source Characterization

An Overview of the SIGMA Research Project - Geotechnical, Geological and Earthquake Engineering ◽

10.1007/978-3-319-58154-5_3 ◽

2017 ◽

pp. 25-55

Author(s):

Alain Pecker ◽

Ezio Faccioli ◽

Aybars Gurpinar ◽

Christophe Martin ◽

Philippe Renault

Keyword(s):

Seismic Source ◽

Source Characterization

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Dense 3D electrical resistivity tomography to understand complex deep landslide structures

10.5194/egusphere-egu21-14522 ◽

2021 ◽

Author(s):

Julien Gance ◽

Orlando Leite ◽

Myriam Lajaunie ◽

Kusnahadi Susanto ◽

Catherine Truffert ◽

...

Keyword(s):

Electrical Resistivity ◽

Large Scale ◽

Electrical Resistivity Tomography ◽

Surface Deformation ◽

Reference Model ◽

Slope Instability ◽

Complex Objects ◽

Alluvial Deposits ◽

Resistivity Tomography ◽

The Village

Large scale slope instabilities are complex objects controlled by multiple parameters. The underground and superficial structure of the slope plays a major role as it often controls water circulations, potentially causing weathering and damaging processes, and permits the local storage of water masses, causing temporary overload. In addition, the structure of the subsurface often delineates rock-volumes with variable mechanical properties, whose spatial distribution greatly influences the behavior of the slope. This work illustrates how Dense 3D Electrical Resistivity Tomography can provide relevant constraints on these parameters.The village of Viella, in France (Hautes-Pyr&#233;n&#233;es), is affected by strong slope movement since 2018, when a massive rockslide above the village modified the stress conditions of the entire slope and, potentially, the hydrogeological context. As a consequence, some houses and infrastructures are progressively damaged, leading to heavy measures (houses evacuation). This complex, deep-seated (> 80 m), slope instability covers an area of ca. 650 000 m&#178;, is primarily composed of altered shists, colluviums, and non-consolidated alluvial deposits, forming several kinematic units with surface velocities in the range [0.5 &#8211; 5] mm.month-1.&#160;A 3D dense electrical resistivity tomography was realized using the FullWaver system, to characterize the structure and the forcing factors of this unstable slope. 55 V-FullWavers receivers (3 -electrodes, 2 channels sensors) were quasi-evenly distributed over a surface area of 400 x 500 m&#178; with an interval of 90 m, apart from the village area, where no electrode could be grounded. Each V-FullWaver recorded signals through two orthogonal dipoles of 25 m length. Current injections were realized with a high-power transmitter (6 kW, 16 A, 3000 V). 235 injection dipoles were used. The system injected current between a fixed remote electrode (more than 1 km away from the site to increase the investigation depth) and a local mobile electrode, moved all over the investigated area in between the V-Fullwaver receivers, with an interval of approximately 40 m, except in the village area.&#160;The resulting 3D resistivity model presents a high spatial variability until 100 to 150 m depth approximately, that highly relates to the complex strain dynamics of the slope and the hydrogeological observations. It highlights the relation between the most active kinematic compartments and the large-scale structure of the slope.It provides a first understanding of the role of local compacted rocks in the buildup of surface deformation but also on the localization of heterogeneities (fissures, scarps) which may relate to water circulation paths.. This 3D image of the slope is the first structural reference model for future hydrogeological and geomechanical studies aiming at deducing the possible evolution of the slope.

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Paleoearthquakes on the Húsavík-Flatey Fault in northern Iceland: Where are the large earthquakes?

10.5194/egusphere-egu21-13998 ◽

2021 ◽

Author(s):

Remi Matrau ◽

Yann Klinger ◽

Jonathan Harrington ◽

Ulas Avsar ◽

Esther R. Gudmundsdottir ◽

...

Keyword(s):

Slip Rate ◽

Late Glacial ◽

Fault Scarp ◽

Alluvial Fan ◽

Tectonic Deformation ◽

Birch Wood ◽

Alluvial Deposits ◽

Slip Rates ◽

Tephra Layers ◽

Large Earthquakes

Paleoseismology is key to study earthquake recurrence and fault slip rates during the Late Pleistocene-Holocene. The H&#250;sav&#237;k-Flatey Fault (HFF) in northern Iceland is a 100 km-long right-lateral transform fault connecting the onshore Northern Volcanic Zone to the offshore Kolbeinsey Ridge and accommodating, together with the Gr&#237;msey Oblique Rift (GOR), ~18 mm/yr of relative motion between the Eurasian and North American plates. Significant earthquakes occurred on the HFF in 1755, 1838 and 1872 with estimated magnitudes of 6.5-7. However, historical information on past earthquakes prior to 1755 is very limited in both timing and size.We excavated five trenches in a small basin (Vestari Krubbssk&#225;l) located 5.5 km southeast of the town of H&#250;sav&#237;k and at 300 m.a.s.l. and one trench in an alluvial fan (Tra&#240;arger&#240;i) located 0.5 km north of H&#250;sav&#237;k and at 50 m.a.s.l. In a cold and wet environment, such as in coastal parts of Iceland, one has to take into account periglacial processes affecting the topsoil to discriminate tectonic from non-tectonic deformation. We used tephra layers in the Vestari Krubbssk&#225;l and Tra&#240;arger&#240;i trenches as well as birch wood samples in Tra&#240;arger&#240;i to constrain the timing of past earthquakes. Tephra layers Hekla-3 (2971 BP) and Hekla-4 (4331&#177;20 BP) are visible in the top half of all the trenches. In addition, a few younger tephra layers are visible in the top part of the trenches. In Tra&#240;arger&#240;i several dark layers rich in organic matter are found, including birch wood-rich layers from the Earlier Birch Period (9000-7000 BP) and the Later Birch Period (5000-2500 BP). In Vestari Krubbssk&#225;l the lower halves of the trenches display mostly lacustrine deposits whereas in Tra&#240;arger&#240;i the lower half of the trench shows alluvial deposits overlaying coarser deposits (gravels/pebbles) most likely of late-glacial or early post-glacial origins. In addition, early Holocene tephra layers are observed in some of the trenches at both sites and may correspond to Askja-S (10800 BP), Saksunarvatn (10300 BP) and Vedde (12100 BP). These observations provide good age constraints and suggest that both the Vestari Krubbssk&#225;l and Tra&#240;arger&#240;i trenches cover the entire Holocene.Trenches at both sites show significant normal deformation in addition to strike-slip, well correlated with their larger scale topographies (pull-apart basin in Vestari Krubbssk&#225;l and 45 m-high fault scarp in Tra&#240;arger&#240;i). We mapped layers, cracks and faults on all trench walls to build a catalogue of Holocene earthquakes. We identified events based on the upward terminations of the cracks and retrodeformation. Our results yield fewer major earthquakes than expected, suggesting that large earthquakes (around magnitude 7) are probably rare and the more typical HFF earthquakes of magnitude 6-6.5 likely produce limited topsoil deformation.[yk1]&#160; Our interpretation also suggests that the Holocene slip rate [yk2]&#160;for the fault section we are studying may be slower than the estimated geodetic slip rate (6 to 9 mm/yr)[yk3]&#160; for the entire onshore HFF, although secondary onshore sub-parallel fault strands could accommodate part of the deformation.

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