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W.W. Wood

Publications and source records attributed to W.W. Wood.

23 records · Page 2Linked to original sources
USGS1987

Playa-lake basins on the Southern High Plains of Texas and New Mexico: Part I. Hydrologic, geomorphic, and geologic evidence for their development

Playa-lake basins of the Southern High Plains, Texas and New Mexico, may originate wherever water periodically can collect in a surficial depression. They expand, however, by hydrologic and geomorphic processes including (1) dissolution of lithologic carbonates by infiltrating water; (2) transport downward of fine-grained clastic and organic material by the infiltrating ground water, leading to continuing processes of oxidation and carbonate dissolution in the subsurface; and (3) eolian removal of clastic material from the floor of playa lakes, which at some sites appears to have deepened playa depressions. Evidence for largely hydrologic processes of playa-basin development on the Southern High Plains includes (1) a geographic occurrence restricted to relatively flat areas of the High Plains surface that have poorly developed fluvial drainage and which are underlain by generally unsaturated clastic and calcrete beds; (2) a tendency to occur where water collects and infiltrates, as along ephemeral streams and lineations suggestive of fracture systems; and (3) hydrologic, geochemical, petrographic, and bore-hole data, which suggest that recharge to the High Plains aquifer is principally from playa lakes, that various geochemical changes including carbonate dissolution and enhancement of secondary porosity occur as water moves downward through the unsaturated zone beneath playa lakes, and that calcrete beds often are missing or significantly dissolved beneath playa floors.

Texas, New Mexico↗
USGS1987

Playa-lake basins on the Southern High Plains of Texas and New Mexico: Part II. A hydrologic model and mass-balance arguments for their development.

Hydrologic, geologic, geomorphic, and mass-balance data suggest that most of the ∼30,000 playa lake basins on the Southern High Plains have developed by a combination of dissolution of caliche and piping of surface material into the unsaturated zone rather than by eolian processes as has generally been stated. A conceptual model suggests that particulate organic material, much of which is sorbed on smectite clays, is carried downward from the surface into the unsaturated zone by recharging water. The organic material is oxidized to CO 2 , which dissolves in the water, forms carbonic acid, and dissolves lithologic carbonates. Because organic material is transported and oxidized deep in the unsaturated zone, CO 2 concentrations are much higher at depth than in the soil zone, and recharging water remains thermodynamically subsaturated with respect to carbonates and thus able to dissolve them throughout the unsaturated zone. Dissolution promotes lithologic instability, leading to piping and eluviation of material within the unsaturated zone. Playa basins expand laterally as recharge is concentrated at the edge of the playa floor because of lowered permeability in the center that results from accumulation of clays and other fine sediment. Mass-balance calculations of gas, liquid, and solid fluxes beneath a playa basin suggest that sufficient mass is transported to account for the volume of the depression. Particulate flux is estimated by relating it to the CO 2 flux out of the unsaturated zone. Solute flux is estimated from the difference between input values from the playa lake water and that observed in ground water. Gas flux is measured directly from gas samples at specific depths below the: surface.

Geological Society of America Bulletin↗
USGS1985

Origin of caves and other solution openings in the unsaturated (vadose) zone of carbonate rocks: A model for CO2 generation

The enigma that caves and other solution openings form in carbonate rocks at great depths below land surface rather than forming from the surface downward can be explained by the generation of CO2 within the aquifer system. In the proposed model, CO2 is generated by the oxidation of particulate and/or dissolved organic carbon that is transported from the land surface deep into the unsaturated zone by recharging ground water. The organic material is oxidized to CO2 by aerobic bacteria utilizing oxygen that diffuses in from the atmosphere. Because gas transport in the unsaturated zone is controlled largely by diffusion, steady-state generation of even minute amounts of CO2 deep in the unsaturated zone results in the creation of large concentrations of CO2 at depth as it establishes a concentration gradient to the surface or other sink.

Geology↗
USGS1981

Preliminary data from a series of artificial recharge experiments at Stanton, Texas

A series of artificial recharge experiments was conducted by the U.S. Geological Survey at an experimental site located in Stanton, Texas. Five tests were performed from March 1977 through December 1978 to: (1) Evaluate the hydraulic properties of the aquifer; (2) test sampling and monitoring equipment; (3) compare tracers for future use in hydrologic investigations; and (4) determine the radial and vertical distribution of hydraulic properties at the site. Suites of inorganic, and both volatile and nonvolatile organic tracers were used in the tests, and comparative data were obtained from sampling points at several radial distances and depths from the injection well. Hydraulic data from aquifer tests and geologic data from core material also were obtained during the investigation.

Texas↗