Publications
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Geology and stratigraphic correlation of the Murray and Carolyn Shoemaker formations across the Glen Torridon region, Gale crater, Mars
The Glen Torridon (GT) region within Gale crater, Mars, occurs in contact with the southern side of Vera Rubin ridge (VRR), a well-defined geomorphic feature that is comparatively resistant to erosion. Prior to detailed ground-based investigation of GT, its geologic relationship with VRR was unknown. Distinct lithologic subunits within the Jura member (Murray formation), which forms the upper part
Authors
Christopher M. Fedo, Alexander Bryk, Lauren A. Edgar, Kristen A. Bennett, Valerie K. Fox, William E. Dietrich, Steve G. Banham, Sanjeev Gupta, Kathryn M. Stack, Rebecca Williams, John P. Grotzinger, Nathan Stein, Dave Rubin, Gwenael Caravaca, Ray E. Arvidson, Madison N Hughes, Abigail A. Fraeman, Ashwin R. Vasavada, Juergen Schieber, Brad Sutter
Earthquakes in the shadows: Why aftershocks occur at surprising locations
For decades there has been a debate about the relative effects of dynamic versus static stress triggering of aftershocks. According to the static Coulomb stress change hypothesis, aftershocks should not occur in stress shadows—regions where static Coulomb stress has been reduced. We show that static stress shadows substantially influence aftershock occurrence following three M ≥ 7 California mains
Authors
Jeanne L. Hardebeck, Ruth A. Harris
Using machine learning techniques with incomplete polarity datasets to improve earthquake focal mechanism determination
Earthquake focal mechanisms are traditionally produced using P‐wave first‐motion polarities and commonly require well‐recorded seismicity. A recent approach that is less dependent on high signal‐to‐noise exploits similar waveforms to produce relative polarity measurements between earthquake pairs. Utilizing these relative polarity measurements, it is possible to produce composite focal mechanisms
Authors
Robert Skoumal, David R. Shelly, Jeanne L. Hardebeck
Comparing root cohesion estimates from three models at a shallow landslide in the Oregon Coast Range
Although accurate root cohesion model estimates are essential to quantify the effect of vegetation roots on shallow slope stability, few means exist to independently validate such model outputs. One validation approach for cohesion estimates is back-calculation of apparent root cohesion at a landslide site with well-documented failure conditions. The catchment named CB1, near Coos Bay, Oregon, USA
Authors
Collin Cronkite-Ratcliff, Kevin M. Schmidt, Charlotte Wirion
Spaceborne InSAR mapping of landslides and subsidence in rapidly deglaciating terrain, Glacier Bay National Park and Preserve and vicinity, Alaska and British Columbia
The Glacier Bay area in southeastern Alaska and British Columbia, encompassing Glacier Bay National Park and Preserve, has experienced rapid glacier retreat since the end of the Little Ice Age in the mid-1800s. The impact that rapid deglaciation has had on the slope stability of valley walls and on the sedimentation of fans and deltas adjacent to fjords and inlets is an ongoing research topic. Usi
Authors
Jinwook Kim, Jeffrey A. Coe, Zhong Lu, Nikita N. Avdievitch, Chad Hults
Impact of sedimentary basins on Green’s functions for static slip inversion
Earthquakes often occur in regions with complex material structure, such as sedimentary basins or mantle wedges. However, the majority of co-seismic modelling studies assume a simplified, often homogeneous elastic structure in order to expedite the process of model construction and speed up calculations. These co-seismic forward models are used to produce Green’s functions for finite-fault inversi
Authors
Leah Langer, Stephen Beller, Evan Tyler Hirakawa, Jeroen Tromp
Geoelectric constraints on the Precambrian assembly and architecture of southern Laurentia
Using images from an updated and expanded three-dimensional electrical conductivity synthesis model for the contiguous United States (CONUS), we highlight the key continent-scale geoelectric structures that are associated with the Precambrian assembly of southern Laurentia. Conductivity anomalies are associated with the Trans-Hudson orogen, the Penokean suture, the ca. 1.8–1.7 Ga Cheyenne belt and
Authors
Benjamin Scott Murphy, Paul A. Bedrosian, Anna Kelbert
Aqueously altered igneous rocks sampled on the floor of Jezero crater, Mars
The Perseverance rover landed in Jezero crater, Mars, to investigate ancient lake and river deposits. We report observations of the crater floor, below the crater’s sedimentary delta, finding the floor consists of igneous rocks altered by water. The lowest exposed unit, informally named Séítah, is a coarsely crystalline olivine-rich rock, which accumulated at the base of a magma body. Fe-Mg carbon
Authors
K.A. Farley, K.M. Stack, D.L. Shuster, B.H.N. Horgan, J.A. Hurowitz, J. D. Tarnas, J.I. Simon, V.Z. Sun, E.L. Scheller, K.R. Moore, S.M. McLennan, P.M. Vasconcelos, R. C. Wiens, A.H. Treiman, L.E. Mayhew, O. Beyssac, T.V. Kizovski, N. J. Tosca, K.H. Williford, L.S. Crumpler, L.W. Beegle, J.F. Bell III, B.L. Ehlmann, Y. Liu, J.N. Maki, M. E. Schmidt, A.C. Allwood, H.E.F. Amundsen, R. Ghartia, T. Bosak, A.J. Brown, B. C. Clark, A. Cousin, O. Forni, Travis S. J. Gabriel, Y. Goreva, S. Gupta, S.-E. Hamran, C.D.K. Herd, K. Hickman-Lewis, J.R. Johnson, L.C. Kah, P. B. Kelemen, K.B. Kinch, L. Mandon, N. Mangold, C. Quantun-Nataf, M.S. Rice, P.S. Russell, S. Sharma, S. Siljestroem, A. Steele, R. Sullivan, M. Wadhwa, B. P. Weiss, A.J. Williams, B.V. Wogsland, P.A. Willis, T.A. Acosta-Maeda, B. Peck, K. Benzerara, S. Bernard, A.S. Burton, E. L. Cardarelli, B. Chide, E. Clave, E.A. Cloutis, A.D. Czaja, V. Debaille, E. Dehouck, A.G. Fairen, D.T. Flannery, S.Z. Fleron, T. Fouchet, J. Frydenvang, B.J. Garczynski, E.F. Gibbons, E. M. Hausrath, A.G. Hayes, J. Henneke, J.L. Jorgensen, E.M. Kelly, J. Lasue, S. Le Mouelic, J. M. Madariaga, S. Maurice, M. Merusi, P. -Y. Meslin, S.M. Milkovich, C.C. Million, R.C. Moeller, J.I. Nunez, A.M. Ollila, G. Paar, D.A. Paige, D.A.K. Pedersen, P. Pilleri, C. Pilorget, P.C. Pinet, J.W. Rice Jr., C. Royer, V. Sautter, M. Schulte, M. A. Sephton, S.K. Sharma, S.F. Sholes, N. Spanovich, M. St. Clair, C.D. Tate, K. Uckert, S.J. VanBommel, A.G. Yanchilina, M. -P. Zorzano
Interseismic lithospheric response of the southern end of the Cascadia Subduction Zone since the 1992 Cape Mendocino M 7.1 earthquake
No abstract available.
Authors
Jessica (Jessie) L Vermeer, Mark Hemphill-Haley
Revised earthquake recurrence intervals in California, USA: New paleoseismic sites and application of event likelihoods
Recurrence intervals for ground rupturing earthquakes are critical data for assessing seismic hazard. Recurrence intervals are presented here for 38 paleoseismic sites in California. Eleven of these include new or updated data; the remainder use data previously included in the Unified California Earthquake Rupture Forecast Version 3 (UCERF3). The methods and results are consistent with UCERF3. In
Authors
Devin McPhillips
Quantifying modeling uncertainty in simplified beam models for building response prediction
The use of simple models for response prediction of building structures is preferred in earthquake engineering for risk evaluations at regional scales, as they make computational studies more feasible. The primary impediment in their gainful use presently is the lack of viable methods for quantifying (and reducing upon) the modeling errors/uncertainties they bear. This study presents a Bayesian ca
Authors
S. Farid Ghahari, Khachik Sargsyan, Mehmet Çelebi, Ertugrul Taciroglu
Simplifying complex fault data for systems-level analysis: Earthquake geology inputs for U.S. NSHM 2023
As part of the U.S. National Seismic Hazard Model (NSHM) update planned for 2023, two databases were prepared to more completely represent Quaternary-active faulting across the western United States: the NSHM23 fault sections database (FSD) and earthquake geology database (EQGeoDB). In prior iterations of NSHM, fault sections were included only if a field-measurement-derived slip rate was estimate
Authors
Alexandra Elise Hatem, Camille Marie Collett, Richard W. Briggs, Ryan D. Gold, Stephen J. Angster, Edward H. Field, Peter M. Powers