Publications

Landslide volumes span many orders of magnitude, but large-volume slides tend to travel farther and consequently can pose a greater hazard. In northwest Washington State, USA, a landscape abounding with landslides big and small, the recent occurrence of the large-volume and tragically deadly State Route 530 (Oso) landslide is a stark reminder of the hazards associated with glacial...

The Eastern California Shear Zone (ECSZ) is a wide zone of late Cenozoic strike-slip faults and related diffuse deformation that currently accommodates ~20–25% of relative Pacific–North America plate motion in the lower Colorado River region (Fig. 1A; Dokka and Travis, 1990; Miller et al., 2001; Guest et al., 2007; Mahan et al., 2009). The ECSZ is kinematically linked southward to...

The middle Paleozoic through Present tectonic evolution of the Northern Cordillera is portrayed in a series of 15 Tectonic Model figures. These figures depict the successive stages of formation and accretion of orogenic collages along the western margin of the North American Plate (craton and craton margin) and adjacent marine areas. The orogenic collages are composed of terranes and...

The Talkeetna Formation is a prominent lithostratigraphic unit in south-central Alaska. In the Iniskin–Tuxedni area, Detterman and Hartsock (1966) divided the formation into three mappable units including, from oldest to youngest, the Marsh Creek Breccia, the Portage Creek Agglomerate, and the Horn Mountain Tuff Members. The Horn Mountain Tuff Member was thought to include rocks...

Geochemical data suggest the source of oil in upper Cook Inlet fields is Middle Jurassic organic-rich shales in the Tuxedni Group (Magoon and Anders, 1992; Lillis and Stanley, 2011; LePain and others, 2012, 2013). Of the six formations in the group (Detterman, 1963), the basal Red Glacier Formation is the only unit that includes fine-grained rocks in outcrop that appear to be organic...

The Division of Geological & Geophysical Surveys and Division of Oil & Gas are currently conducting a study of the hydrocarbon potential of Cook Inlet forearc basin (Gillis, 2013, 2014; LePain and others, 2013; Wartes, 2015; Herriott, 2016 [this volume]). The Middle Jurassic Tuxedni Group is recognized as a major source of oil in Tertiary reservoirs (Magoon, 1994), although the potential...

During the past 15 yr, the global requirement for fertilizers has grown considerably, mainly due to demand by a larger and wealthier world population for more and higher-quality food. The demand and price for potash as a primary fertilizer ingredient have increased in tandem, because of the necessity to increase the quantity and quality of food production on the decreasing amount of...

Lurking below the twin concepts of connectivity and disconnectivity are their first, and in some ways, richer cousins: continuity and discontinuity. In this paper we explore how continuity and discontinuity represent fundamental and complementary perspectives in fluvial geomorphology, and how these perspectives inform and underlie our conceptions of connectivity in landscapes and rivers...

The Bonneville Flood was one of the largest floods on Earth. First discovered by G.K. Gilbert in the 1870s during his inspection of the outlet at Red Rock Pass, it was rediscovered in the 1950s by Harold Malde and coworkers, leading to mapping and assessment of spectacular flood features along Marsh Creek, Portneuf River, and Snake River for over 1100 km between the outlet and Lewiston...

This report summarizes the primary sources of potash in the United States. Potash is an essential nutrient that, along with phosphorus and nitrogen, is used as fertilizer for growing crops. Plants require sufficient potash to activate enzymes, which in turn catalyze chemical reactions important for water uptake and photosynthesis. When potassium is available in quantities necessary for...

This map shows the generalized geology of Alaska, which helps us to understand where potential mineral deposits and energy resources might be found, define ecosystems, and ultimately, teach us about the earth history of the State. Rock units are grouped in very broad categories on the basis of age and general rock type. A much more detailed and fully referenced presentation of the...

Chemical analyses from 71 watersheds across an ∼450 km transect in west-central Panama provide insight into controls on weathering and rates of chemical denudation and CO2 consumption across an igneous arc terrain in the tropics. Stream and river compositions across this region of Panama are generally dilute, having a total dissolved solute value = 118 ± 91 mg/L, with bicarbonate and...