scholarly journals Selected chemical analyses of water from formations of Mesozoic and Paleozoic age in parts of Oklahoma, northern Texas, and Union County, New Mexico

1987 ◽  
Keyword(s):  
New Mexico ◽  
Chemical Analyses ◽  
Union County

Correlation of a Volcanic Ash bed in Pleistocene Deposits near Mount Blanco, Texas, with the Guaje Pumice Bed of the Jemez Mountains, New Mexico

1972 ◽  
Vol 2 (4) ◽  
pp. 554-578 ◽  
Author(s):  
Glen A. Izett ◽  
Ray E. Wilcox ◽  
Glenn A. Borchardt
Keyword(s):  
New Mexico ◽  
Volcanic Ash ◽  
Fission Track ◽  
Major Elements ◽  
Flow Sheet ◽  
Chemical Analyses ◽  
Sedimentary Deposits ◽  
Jemez Mountains ◽  
Bandelier Tuff ◽  
Minimum Age

A rhyolitic volcanic ash bed about 0.3 m thick is exposed in a roadcut along Texas Highway 193 near Mount Blanco in the upper part of a sequence of Pleistocene sedimentary deposits at the type locality of the Blanco Formation, about 59 km northeast of Lubbock, Texas. This ash, here named informally the Guaje ash bed, has chemical and petrographic characteristics closely resembling those of the rhyolitic air-fall tephra (Guaje Pumice Bed) that directly underlies ash flows of Pleistocene age in the Jemez Mountains of northern New Mexico. The Guaje Pumice Bed and the ash flows belong to the Otowi Member of the Bandelier Tuff. Properties common to the Guaje ash bed and the Guaje Pumice Bed include: refractive index of glass, 1.497–1.498; microphenocrysts of quartz, sanidine (Or42–44), ferrohedenbergite (Fe51Ca42Mg7), chevkinite, allanite, zircon, and magnetite. Chemical composition of the glass of the Guaje ash bed matches that of the Guaje Pumice Bed for all major elements except K and Na and for trace elements determined by standard chemical analyses, atomic absorption, and neutron activation. Paleomagnetic measurements indicate that the ash has reverse depositional remanent magnetization. Glass shards of the ash have a fission-track age of about 1.4 ± 0.2 m. y. Sanidine from the Guaje Pumice Bed and its genetically related ash-flow sheet in the Jemez Mountains was K-Ar dated at about 1.4 m. y. by R. R. Doell and his colleagues in 1968. Correlation of the Guaje ash bed with the radiometrically dated Guaje Pumice Bed establishes a minimum age of about 1.4 m. y. for the Blanco Formation.

A Phytosaur in Union County, New Mexico with Notes on the Stratigraphy

1939 ◽  
Vol 47 (7) ◽  
pp. 759-766 ◽  
Author(s):  
J. Willis Stovall ◽  
Donald E. Savage
Keyword(s):  
New Mexico ◽  
Union County

A Note on the Nosean Phonolite of the Wolf Rock, Cornwall

1959 ◽  
Vol 96 (6) ◽  
pp. 503-504 ◽  
Author(s):  
C. E. Tilley
Keyword(s):  
New Mexico ◽  
Trace Element ◽  
Element Distribution ◽  
Trace Element Distribution ◽  
Chemical Analyses ◽  
Early Date ◽  
Fresh Rock

The first systematic descriptions of the nosean phonolite of the Wolf Rock were given by Allport (Geol. Mag., 1871, p. 247; 1874, p. 462). Later a fuller account of the rock was provided by Teall in his British Petrography (1888, pp. 367–368). Since that time the rock has been repeatedly figured in text-books of petrography and in the light of two chemical analyses provided by J. A. Phillips (in Allport, 1871), regarded as a type example of a more sodic phonolite chemically comparable with the plutonic mariupolite. In view of the early date of these analyses, Mr. J. H. Scoon has at my request carried out a new analysis of the fresh rock, the results of which are provided in Table 1 (No. 1). This analysis reveals significant differences from the original, particularly in the potash content and shows that the rock is to be compared with the well-known phonolite of Brüx, Bohemia (Table 1, No. 3), and a phonolite from Colfax Co., New Mexico (Table 1, No. 2). The trace element distribution in the Wolf Rock has also been kindly determined for me by Dr. S. R. Nockolds (Table 1). Some additional mineralogical data which re-examination of the rock has provided may now be set down.

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