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C.L. Jones

Publications and source records attributed to C.L. Jones.

9 recordsLinked to original sources
USGS2008

Assessing the extent and diversity of riparian ecosystems in Sonora, Mexico

Conservation of forested riparian ecosystems is of international concern. Relatively little is known of the structure, composition, diversity, and extent of riparian ecosystems in Mexico. We used high- and low-resolution satellite imagery from 2000 to 2006, and ground-based sampling in 2006, to assess the spatial pattern, extent, and woody plant composition of riparian forests across a range of spatial scales for the state of Sonora, Mexico. For all 3rd and higher order streams, river bottomlands with riparian forests occupied a total area of 2,301 km2. Where forested bottomlands remained, on average, 34% of the area had been converted to agriculture while 39% remained forested. We estimated that the total area of riparian forest along the principal streams was 897 km2. Including fencerow trees, the total forested riparian area was 944 km2, or 0.5% of the total land area of Sonora. Ground-based sampling of woody riparian vegetation consisted of 92, 50 m radius circular plots. About 79 woody plant species were noted. The most important tree species, based on cover and frequency, were willow species Salix spp. (primarily S. goodingii and S. bonplandiana), mesquite species Prosopis spp. (primarily P. velutina), and Fremont cottonwood Populus fremontii. Woody riparian taxa at the reach scale showed a trend of increasing diversity from north to south within Sonora. Species richness was greatest in the willow-bald cypress Taxodium distichum var. mexicanum-Mexican cottonwood P. mexicana subsp. dimorphia ecosystem. The non-native tamarisk Tamarix spp. was rare, occurring at just three study reaches. Relatively natural stream flow patterns and fluvial disturbance regimes likely limit its establishment and spread. ?? 2008 Springer Science + Business Media BV.

Biodiversity and Conservation↗
USGS1986

Data on the distribution and abundance of submersed aquatic vegetation in the tidal Potomac River, Maryland, Virginia, and the District of Columbia, 1985

This report summarizes data on the distribution and abundance of submersed aquatic vegetation collected in the tidal Potomac River during 1985. Plant species were identified and dry weight determined for selected sites. Information on competition between Hydrilla verticillata and other species was measured. Water-quality characteristics measured include temperature, specific conductance, dissolved oxygen, pH, and transparency as indicated by Secchi depth. A map was made of the distribution of submersed aquatic vegetation based on transect samples and a complete shoreline survey. (USGS)

Open-File Report↗
USGS1978

Test drilling for potash resources: Waste Isolation Pilot Plant Site, Eddy County, New Mexico

Twenty-one borings to augment existing information on potash resources at the proposed site for a waste isolation pilot plant in eastern Eddy County, N. Mex., were drilled and logged in an 11-week period, mid-August to November 1976. The basic data developed from the borings are tabulated in the present report. The tabulation includes lithologic and geophysical logs of all the borings, as well as the results of chemical analyses, X-ray determinations, and calculations to establish a modal mineralogical composition of core samples from potash ore zones and mineralized salt beds.

Open-File Report↗
USGS1975

Potash resources in part of Los Medanos area of Eddy and Lea Counties, New Mexico

Los Medanos area of eastern Eddy and western Lea Counties, New Mexico, is being considered for possible siting of a repository Facility for experimental studies of nuclear-waste emplacement in salt beds of the Salado Formation of Permian age. The potential repository site encompasses about 29 square miles (75 square kilometres) of sandy terrain near the center of Los Medanos. The site is underlain by evaporite and red bed formations having an aggregate thickness of 4,462 feet (1,360 metres). The Salado Formation, which is the main salt-bearing unit of the area, lies at a depth of 1,000 feet (305 metres). The formation is almost 1,970 feet (600 metres) of rock salt with prominent interbeds of anhydrite, polyhalite, glauberite, some widely spaced seams of fine-grained clastic rocks, and a few potash deposits containing sylvite and langbeinite. The potash deposits occur in salt beds 517-871 feet (158-265 metres) below the top of the formation. The lower half of the formation includes some salt beds which may be used for the experimental emplacement of nuclear wastes. Most, if not nearly all, of the potential repository site is underlain by potash deposits that contain sylvite and langbeinite. The deposits grade 12-13 percent K2O as sylvite and 3-11 percent K2O as langbeinite, and must be regarded as having economic potential for potassium minerals. There is considerable uncertainty concerning the full extent and total range in quality of the ores in the deposit, and subsurface investigation will be required to assess their potential.

Open-File Report↗
USGS1973

Salt deposits in Los Medanos area, Eddy and Lea Counties, New Mexico

The salt deposits of Los Medanos area, in Eddy and Lea Counties, southeastern New Mexico, are being considered for possible use as a receptacle for radioactive wastes in a pilot-plant repository. The salt deposits of the area. are in three evaporite formations: the Castile, Salado, and Rustler Formations, in ascending order. The three formations are dominantly anhydrite and rock salt, but some gypsum, potassium ores, carbonate rock, and fine-grained clastic rocks are present. They have combined thicknesses of slightly more than 4,000 feet, of which roughly one-half belongs to the Salado. Both the Castile and the Rustler are-richer in anhydrite-and poorer in rock salt-than the Salado, and they provide this salt-rich formation with considerable Protection from any fluids which might be present in underlying or overlying rocks. The Salado Formation contains many thick seams of rock salt at moderate depths below the surface. The rock salt has a substantial cover of well-consolidated rocks, and it is very little deformed structurally. Certain geological details essential for Waste-storage purposes are unknown or poorly known, and additional study involving drilling is required to identify seams of rock salt suitable for storage purposes and to establish critical details of their chemistry, stratigraphy, and structure.

New Mexico↗
USGS1968

Potential for potash and other evaporite mineral resources in West Pakistan

Reconnaissance examination of marine evaporites in West Pakistan has revealed a highly favorable resource situation with respect to anhydrite, and a potentially favorable position for potash and sulfur. Further work is needed to evaluate the preliminary interpretations made during the present study. The establishment of a potash resource organization within the Mineral Resource Directorate of the Geological Survey of Pakistan is proposed. The organization would be concerned exclusively with the investigation of potash deposits in the Salt Range and adjacent parts of the Potwar and Indus Plains.

Open-File Report↗