We investigated the role of increasingly well-constrained geologic structures in the subsurface (i.e., subsurface architecture) in predicting streambed flux and hyporheic residence time distribution (RTD) for a headwater stream. Five subsurface realizations with increasingly resolved lithological boundaries were simulated in which model geometries were based on increasing information about flow...

Coordinated research efforts are underway on three continents (North America, Europe, Australia) to study naturally occurring carbon dioxide deposits, in order to address fundamental questions and concerns about the long-term storage of CO2 in geologic formations. Natural accumulations of carbon dioxide exist in many geologic basins. Some deposits are stored in secure and impermeable traps, whe...

In this paper we describe CO2-PENS, a comprehensive system-level computational model for performance assessment of geologic sequestration of CO2. CO2-PENS is designed to perform probabilistic simulations of CO2 capture, transport and injection in different geologic reservoirs. Additionally, the long-term fate of CO2 injected in geologic formations, including

Sonic velocities of geologic fluids, such as volcanic magmas and geothermal fluids, can be as low as 1 m/s. Critical velocities in large rivers can be of the order of 1-10 m/s. Because velocities of fluids moving in these settings can exceed these characteristic velocities, sonic and supersonic gas flow and critical and supercritical shallow-water flow can occur. The importance of the low chara...

The 1994 Northridge, California, earthquake is the first earthquake for which we have all of the data sets needed to conduct a rigorous regional analysis of seismic slope instability. These data sets include (1) a comprehensive inventory of triggered landslides, (2) about 200 strong-motion records of the mainshock, (3) 1:24,000-scale geologic mapping of the region, (4) extensive data on enginee...

The reemerging field of Medical Geology is concerned with the impacts of geologic materials and geologic processes on animal and human health. Most medical geology research has been focused on health problems caused by excess or deficiency of trace elements, exposure to ambient dust, and on other geologically related health problems or health problems for which geoscience tools, techniques, or ...

Tahltan Lake (104G113) map areas. This work adjoins and locally updates mapping in the Yehiniko Lake and Scud River areas (Brown and Gunning, IY8Y)a. b: Brown and Greig; IYYO. Browl: c t r r l . , 1990). The project objectives are to provide new 1:SO OOO-scale geologic maps accompanied by up-to-date geochemical and mineral occurrence data. and an assessment of thc mineral potential of the area....

Thirty-four permitted earthen waste storage structures (EWSS) were investigated to characterize their hydrogeologic setting using digital soils data, digital elevation data, geologic maps, and oblique aerial photographs. Nearly 18 percent of the sites were constructed above alluvial aquifers and on flood plains. More than half of the area within 3.2 km of most sites had soils with a vertical pe...

We present a revised estimate of Earth’s surface heat flux that is based upon a heat flow data-set with 38 347 measurements, which is 55% more than used in previous estimates. Our methodology, like others, accounts for hydrothermal circulation in young oceanic crust by utilising a half-space cooling approximation. For the rest of Earth’s surface, we estimate the average heat flow for different ...

The reliability of any survey of biodiversity through geologic time depends on the rigor and consistency by which taxa are recognized and samples are identified. The main goal of the Neogene Marine Biota of Tropical America (‘NMITA’) project is to create an online biotic database (http://nmita.geology.uiowa.edu) containing images and synoptic taxonomic information that are essential to collecti...