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Geologic characteristics and movement of the Meadow Creek landslide, part of the Coal Hill landslide complex, western Kane County, Utah

The Meadow Creek landslide, part of the Coal Hill landslide complex in western Kane County, Utah, is about 1.7 miles (2.7 km) wide and 1.3 miles (2.1 km) long and contains six smaller historical slides. The upper part of the Meadow Creek landslide is gently sloping and consists of displaced and back-rotated blocks of Cretaceous Dakota and Cedar Mountain Formations that form northeast- to locally
Authors
Francis X. Ashland, Greg N. McDonald

Conodont biostratigraphy of a more complete Reef Trail Member section near the type section, latest Guadalupian Series type region

The original type section of the Reef Trail Member (uppermost part of the Bell Canyon Formation) is called the Park Boundary Section, and is less than satisfactory in several aspects. We propose a new reference section designated Reef Trail Reference section 1 (RTR1) on the same hill as the original type section. Section RTR1 compensates for some of the Park Boundary Section’s shortcomings, includ
Authors
Bruce R. Wardlaw, L.L. Lambert, G.L. Bell, J.A. Fronimos, M.O. Yisa

Aviation response to a widely dispersed volcanic ash and gas cloud from the August 2008 eruption of Kasatochi, Alaska, USA

The extensive volcanic cloud from Kasatochi's 2008 eruption caused widespread disruptions to aviation operations along Pacific oceanic, Canadian, and U.S. air routes. Based on aviation hazard warnings issued by the National Oceanic and Atmospheric Administration, U.S. Geological Survey, the Federal Aviation Administration, and Meteorological Service of Canada, air carriers largely avoided the volc
Authors
Marianne Guffanti, David J. Schneider, Kristi L. Wallace, Tony Hall, Dov R. Bensimon, Leonard J. Salinas

Pliocene climate

The Pliocene Epoch, 5.3 Ma to 1.8 Ma, was a time when paleoclimate conditions ranged from very warm, equable climates (on a global scale), rhythmically varying every 40,000 years, to high-amplitude glacial-interglacial cycles that led to the “Ice Ages” of the Pleistocene. Evidence for paleoclimate conditions comes from fossils, geochemical data, and the integration of these data with sophisticated
Authors
Harry J. Dowsett, R. P. Caballero-Gill

A model for Iapetan rifting of Laurentia based on Neoproterozoic dikes and related rocks

Geologic evidence of the Neoproterozoic rifting of Laurentia during breakup of Rodinia is recorded in basement massifs of the cratonic margin by dike swarms, volcanic and plutonic rocks, and rift-related clastic sedimentary sequences. The spatial and temporal distribution of these geologic features varies both within and between the massifs but preserves evidence concerning the timing and nature o
Authors
William C. Burton, Scott Southworth

Meteoric 10Be in soil profiles - A global meta-analysis

In order to assess current understanding of meteoric 10Be dynamics and distribution in terrestrial soils, we assembled a database of all published meteoric 10Be soil depth profiles, including 104 profiles from 27 studies in globally diverse locations, collectively containing 679 individual measurements. This allows for the systematic comparison of meteoric 10Be concentration to other soil characte
Authors
Joseph A. Graly, Paul R. Bierman, Lucas J. Reusser, Milan J. Pavich

Mid-Piacenzian sea surface temperature record from ODP Site 1115 in the western equatorial Pacific

Planktic foraminifer assemblages and alkenone unsaturation ratios have been analyzed for the mid-Piacen-zian (3.3 to 2.9 Ma) section of Ocean Drilling Program (ODP) Site 1115B, located in the western equatorial Pacific off the coast of New Guinea. Cold and warm season sea surface temperature (SST) estimates were determined using a modern analog technique. ODP Site 1115 is located just south of the
Authors
Danielle Stoll

Modern climate challenges and the geological record

Today's changing climate poses challenges about the influence of human activity, such as greenhouse gas emissions and land use changes, the natural variability of Earth's climate, and complex feedback processes. Ice core and instrumental records show that over the last century, atmospheric carbon dioxide (CO2) concentrations have risen to 390 parts per million volume (ppmv), about 40% above pre-In
Authors
Thomas M. Cronin

Mid-Piacensian mean annual sea surface temperature: an analysis for data-model comparisons

Numerical models of the global climate system are the primary tools used to understand and project climate disruptions in the form of future global warming. The Pliocene has been identified as the closest, albeit imperfect, analog to climate conditions expected for the end of this century, making an independent data set of Pliocene conditions necessary for ground truthing model results. Because mo
Authors
Harry J. Dowsett, Marci M. Robinson, Kevin M. Foley, Danielle K. Stoll

Rift-related volcanism and karst geohydrology of the southern Ozark Dome

This field trip examines the geology and geohydrology of a dissected part of the Salem Plateau in the Ozark Plateaus province of south-central Missouri. Rocks exposed in this area include karstified, flat-lying, lower Paleozoic carbonate platform rocks deposited on Mesoproterozoic basement. The latter is exposed as an uplift located about 40 mi southwest of the St. Francois Mountains and form the
Authors
Richard W. Harrison, David J. Weary, Randall C. Orndorff, John E. Repetski, Herbert A. Pierce, Gary R. Lowell

Petrography, mineralogy, and geochemistry of deep gravelly sands in the Eyreville B core, Chesapeake Bay impact structure

The ICDP–USGS Eyreville drill cores in the Chesapeake Bay impact structure reached a total depth of 1766 m and comprise (from the bottom upwards) basement-derived schists and granites/pegmatites, impact breccias, mostly poorly lithified gravelly sand and crystalline blocks, a granitic slab, sedimentary breccias, and postimpact sediments. The gravelly sand and crystalline block section forms an app
Authors
Katerina Bartosova, Susanne Gier, J. Wright Horton, Christian Koeberl, Dieter Mader, Henning Dypvik