Publications
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Role of fault gouge during Interaction between hydraulic fracture and a preexisting fracture
Enhanced reservoir connectivity generally requires maximizing the intersection between hydraulic fracture (HF) and preexisting underground natural fractures (NF), while having the hydraulic fracture continue to propagate across the natural fractures. Observations of downhole core samples suggest that these natural fractures are in fact veins filled with minerals such as calcite (Mighani et al., 20
Authors
S. Mighani, David A. Lockner, Brian D. Kilgore, Brian Evans
Quantifying post-wildfire hillslope erosion with lidar
Following a wildfire, flooding and debris- flow hazards are common and pose a threat to human life and infrastructure in steep burned terrain. Wildfire enhances both water runoff and soil erosion, which ultimately shape the debris flow potential. The erosional processes that route excess sediment from hillslopes to debris-flow channels in recently burned areas, however, are poorly constrained. I
Authors
Francis K. Rengers, Luke McGuire
Serpentinite‐rich gouge in a creeping segment of the Bartlett Springs Fault, northern California: Comparison with SAFOD and implications for seismic hazard
An exposure of a creeping segment of the Bartlett Springs Fault (BSF), part of the San Andreas Fault system in northern California, is a ~1.5‐m‐wide zone of serpentinite‐bearing fault gouge cutting through Late Pleistocene fluvial deposits. The fault gouge consists of porphyroclasts of antigorite serpentinite, talc, chlorite, and tremolite‐actinolite, along with some Franciscan metamorphic rocks,
Authors
Diane E. Moore, Robert J. McLaughlin, James J. Lienkaemper
Overview of spirit microscopic imager results
This paper provides an overview of Mars Exploration Rover Spirit Microscopic Imager (MI) operations and the calibration, processing, and analysis of MI data. The focus of this overview is on the last five Earth years (2005–2010) of Spirit's mission in Gusev crater, supplementing the previous overview of the first 450 sols of the Spirit MI investigation. Updates to radiometric calibration using in‐
Authors
Kenneth E. Herkenhoff, Steve W Squyres, Raymond E. Arvidson, Shoshanna B Cole, Rob Sullivan, Aileen Yingst, Nathalie Cabrol, Ella (Contractor) Lee, Janet Richie, Robert M. Sucharski, Fred J. Calef, James F. Bell, Mary Chapman, Paul Geissler, Lauren A. Edgar, Brenda Franklin, Joel A. Hurowitz, Elsa Jensen, Jeffrey R. Johnson, Randolph L. Kirk, Peter Lanagan, Kevin Mullins, Craig Leff, Justin Maki, Bonnie L. Redding, Melissa Rice, Michael H. Sims, Richard Springer, Annette Sunda, Nicole Spanovich, Laurence A. Soderblom, Alicia Vaughan
Honolulu Magnetic Observatory
Tucked in a grove of thorny mesquite trees, on an ancient coral reef on the south side of the Hawaiian island of Oahu, west of Pearl Harbor, a small unmanned observatory quietly records the Earth’s time-varying magnetic field. The Honolulu Magnetic Observatory is 1 of 14 that the U.S. Geological Survey Geomagnetism Program operates at various locations across the United States and its territories
Authors
Jeffrey J. Love, Carol Finn
The extreme space weather event in September 1909
We evaluate worldwide low-latitude auroral activity associated with the great magnetic storm of September 1909 for which a minimum Dst value of −595 nT has recently been determined. From auroral observations, we calculate that the equatorward boundary of the auroral oval in the 1909 event was in the range from 31°–35° invariant latitude (assuming auroral height of 400 km) to 37°–38° (800 km). Thes
Authors
Hisashi Hayakawa, Yusuke Ebihara, Edward W. Cliver, Kentaro Hattori, Shin Toriumi, Jeffrey J. Love, Norio Umemura, Kosuke Namekata, Takahito Sakaue, Takuya Takahashi, Kazunari Shibata
Subsurface controls on the development of the Cape Fear Slide Complex, central US Atlantic Margin
The Cape Fear Slide is one of the largest (>25 000 km3) submarine slope failure complexes on the US Atlantic margin. Here we use a combination of new high-resolution multichannel seismic data (MCS) from the National Science Foundation Geodynamic Processes at Rifting and Subducting Margins (NSF GeoPRISMS) Community Seismic Experiment and legacy industry MCS to derive detailed stratigraphy of this s
Authors
Jenna C. Hill, Daniel S. Brothers, Matthew J. Hornbach, Derek E. Sawyer, Donna J. Shillington, Anne Bécel
Degradation of 100‐m‐scale rocky ejecta craters at the InSight Landing Site on Mars and implications for surface processes and erosion rates in the hesperian and amazonian
Rocky ejecta craters (RECs) at the Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) landing site on Elysium Planitia, Mars, provide constraints on crater modification and rates for the Hesperian and Amazonian. The RECs are between 10 m and 1.2 km in diameter and exhibit five classes of preservation. Class 1 represents pristine craters with sharp rims and abun
Authors
J. Sweeney, N. H Warner, V. Ganti, Matthew P. Golombek, M. P. Lamb, Robin L. Fergason, Randolph L. Kirk
Inhibition of grain boundary sliding creep in fine-grained ice by inter-granular particles: Implications for planetary ice masses
Ice in both terrestrial and planetary settings often contains rock particles. Here we present an experimental investigation of the influence of intergranular particles on the rheological behavior of ice. Experiments were performed on samples fabricated from 10‐μm ice powders +1‐μm graphite or 0.8‐μm alumina particles and subjected to elevated confining pressures. A critical particle fraction, ∼6%,
Authors
Chao Qi, Laura A. Stern, Asmin Pathare, William B. Durham, David L. Goldsby
Unmanned aerial systems capabilities of the U.S. Geological Survey Woods Hole Coastal and Marine Science Center
Unmanned aerial system (UAS) technology provides a rapid and low-cost solution for mapping coastal environments and assessing short- and long-term changes. The interdisciplinary nature of the data collected and the breadth of applications make UAS technology applicable to multiple scientific investigations. The Aerial Imaging and Mapping (AIM) group at the U.S. Geological Survey (USGS) Woods Hole
Authors
Sandra Brosnahan, Christopher R. Sherwood
Do low-cost seismographs perform well enough for your network? An overview of laboratory tests and field observations of the OSOP Raspberry Shake 4D
Seismologists have recently begun utilizing low-cost nodal sensors in dense deployments to sample the seismic wavefield at unprecedented spatial resolution. Earthquake Early Warning Systems (EEWS) and other monitoring networks (e.g. wastewater injection) would additionally benefit from network densification; however, current nodal systems lack power systems and/or real-time data transmission requi
Authors
Robert E. Anthony, Adam T. Ringler, David C. Wilson, Emily Wolin
Uncertainty in United States coastal wetland greenhouse gas inventorying
Coastal wetlands store carbon dioxide (CO2) and emit CO2 and methane (CH4) making them an important part of greenhouse gas (GHG) inventorying. In the contiguous United States (CONUS), a coastal wetland inventory was recently calculated by combining maps of wetland type and change with soil, biomass, and CH4 flux data from a literature review. We assess uncertainty in this developing carbon monitor
Authors
James Holmquist, Lisamarie Windham-Myers, Blanca Bernal, Kristin B. Byrd, Steve Crooks, Meagan Gonneea Eagle, Nathan Herold, Sara Knox, Kevin D. Kroeger, John McCombs, J. Patrick Megonigal, Lu Meng, James Morris, Ariana Sutton-Grier, Tiffany Troxler, Donald Weller