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Research about New Mexico

Source-linked reports with geographic coverage including New Mexico.

At least 973 records · Page 54Linked to original sources

Airborne radioactivity survey in the vicinity of Grants, McKinley and Valencia Counties, New Mexico

An airborne radioactivity survey in the vicinity of Grants, New Mexico, was made on May 28. 1951; aeromagnetic measurements were made concurrently with the radioactivity measurements. Several radioactivity anomalies were noted in conjunction with negative magnetic anomalies; this association is unusual and may reflect a genetic relationship between the uranium mineralization and the geologic structure causing the negative magnetic effect. Further investigation of the vicinity of the anomalies near the Haystack area, including ground magnetometer survey, seems warranted.

New Mexico↗

Alluvial fills near Gallup, New Mexico

Valleys near Gallup, N. Mex., similar to many in the Southwest, were filled in Recent time with alluvium. This material is now being eroded by systems of gullies, and the walls of these gullies provide exposures by which the history of the deposition of the alluvium can be traced. Alluvial fills near Gallup have been eroded at least twice previously within Recent time. The middle fill of the three that are recognizable contains potsherds of Pueblo II age, indicating that deposition was occurring as late as A. D. 1200. The chronology of alluviation and degradation for valleys in the Gallup area appears to agree with that for other valleys in the Southwest which have been studied.

New Mexico↗

Uranium in pegmatites

Uranium and rare-earth minerals are common accessory minerals in pegmatite deposits. No domestic pegmatites have been found that are rich enough to support an economic mining operation for uranium alone; however, small quantities of uranium minerals may be recovered as by-products of feldspar or mica mining. Madagascar is the only country that has produced appreciable tonnages of uranium minerals from pegmatites.A review of the literature and observations in the domestic pegmatite districts show that the uranium and rare earth minerals generally occur in pegmatites or pegmatite units rich in potash feldspar. Recent mineralogical and structural studies of pegmatites by the U. S. Geological Survey indicate that, on the basis of geologic mapping, these units can be projected laterally and in depth with reasonable accuracy. In most places the mineral content of these units can be estimated with sufficient accuracy for development purposes.

New Mexico↗

Notes on some winter birds of north central New Mexico

The observations recorded below were made in Santa Fe, Sandoval and Rio Arriba counties during the winter of 1939-1940. Occasional specimens, 54 in all, collected for racial identification, are deposited in the Museum of Zoology, University of Michigan.

New Mexico↗

Geology of the Roswell artesian basin, New Mexico, and its relation to the Hondo Reservoir and Effect on artesian aquifer storage of flood water in Hondo Reservoir

In the Roswell Basin in southeastern New Mexico artesian water is produced from cavernous zones in the carbonate rocks of the San Andres formation and the lower part of the Chalk Bluff formation, both of Permian age. The Hondo Reservoir, 9 miles west-southwest of Roswell, was completed by the U. S. Bureau of Reclamation in 1907, to store waters of the Rio Hondo for irrigation. The project was not successful, as the impounded water escaped rapidly through holes in the gypsum and limestone of the San Andres formation constituting its floor. Of 27,000 acre~feet that entered the reservoir between 1908 and 1913, only 1,100 acre-feet was drawn Ollt for use, the remainder escaping through the floor of the reservoir. Since 1939, plans have been drawn up by the State Engineer and by Federal agencies to utilize the reservoir to protect Roswell from floods. It has also been suggested that water from the Pecos River might be diverted into underground storage through the reservoir. Sinkholes in the Roswell Basin are largely clustered in areas where gypsum occurs in the bedrock. Collapse of strata is due to solution of underlying rock commonly containing gypsum. Domes occur in gypsiferous strata near Salt Creek. The Bottomless Lakes, sinkhole lakes in the escarpment on the east side of the Pecos, are believed to have developed in north-south hinge-line fractures opened when the westernmost beds in the escarpment collapsed. Collapse was due to solution and removal of gypsiferous rock by artesian water which now fills the lakes.

New Mexico↗