Author: Geological Survey (U.S.)Publisher:
ISBN:
Category : California
Languages : en
Pages : 476
Book Description
List of U.S. Geological Survey Geologic and Water-supply Reports and Maps for California
Author: Geological Survey (U.S.)Publisher:
ISBN:
Category : California
Languages : en
Pages : 476
Book Description
List of U.S. Geological Survey Geologic and Water-supply Reports and Maps for California
Author: Geology of the Point Sur-Lopez Point region, Coast Ranges, California: A part of the Southern California allochthon
Author: Clarence A. Hall, Jr.Publisher: Geological Society of America
ISBN: 0813722667
Category : Science
Languages : en
Pages : 50
Book Description
U.S. Geological Survey Bulletin
Author: Publications of the Geological Survey
Author: U.S. Geological Survey Bulletin
Author: Colin F. WilliamsPublisher:
ISBN:
Category : Argillite
Languages : en
Pages : 214
Book Description
Phosphatic concretions occur within diatomite in the upper part of the Miocene Monterey Formation near Lompoc, Calif. Absence of disruption of fine laminar bedding in the associated sediment by the concretions shows that they formed after complete compaction of the enclosing sediment.The concretions exhibit a strongly concentric color, chemical, and mineralogic zonation. Many of them are composed of a nucleus in which vivianite is the dominant mineral. Amorphous ferric phosphate, mitridatite, and francolite are the dominant phosphatic phases in successive layers toward the surface of the concretions. Cd and As contents increase tenfold from the nucleus outward, reaching a maximum of 2,000 ppm, whereas Ni content, with a maximum of 720 ppm, and Co content show the opposite trend. This mineralogy and elemental composition favor accretion under conditions of continuously increasing Eh and pH, during uplift into the fresh-ground-water zone of the terrestrial environment. Shale-normalized rare-earth-element patterns, however, suggest a marine source for the elements biogenic debris consisting of opal-A, organic matter, and carbonates of the enclosing sediment.
Geological Survey Professional Paper
Author: Geological Survey (U.S.)Publisher:
ISBN:
Category :
Languages : en
Pages : 260
Book Description
U.S. Geological Survey Professional Paper
Author: Publications of the U.S. Geological Survey, 1971-1981
Author: New Publications of the Geological Survey
Author: Geological Survey (U.S.).Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 32
Book Description