1-20 OF 295 RESULTS FOR

Sonoma Volcanics

Results shown limited to content with bounding coordinates.
Follow your search
Access your saved searches in your account

Would you like to receive an alert when new items match your search?
×Close Modal
Sort by
Journal Article
Published: 01 April 1996
Micropaleontology (1996) 42 (1): 79-91.
Journal Article
Journal: GSA Bulletin
Published: 01 July 1972
GSA Bulletin (1972) 83 (7): 2063-2072.
...EDWARD A MANKINEN Abstract Paleomagnetic data and potassium-argon ages indicate that the Sonoma Volcanics was erupted during the Pliocene Gilbert reversed and Gauss normal polarity epochs. The Gilbert reversed epoch is represented in the Howell Mountains east of Napa and east of St. Helena...
Journal Article
Journal: Geosphere
Published: 01 June 2011
Geosphere (2011) 7 (3): 629-657.
...Donald S. Sweetkind; James J. Rytuba; Victoria E. Langenheim; Robert J. Fleck Abstract Volcanic rocks in the Sonoma volcanic field in the northern California Coast Ranges contain heterogeneous assemblages of a variety of compositionally diverse volcanic rocks. We have used field mapping, new...
FIGURES | View All (18)
Image
Map of <b>volcanic</b> source area (<b>Sonoma</b> <b>Volcanics</b>, northeast part of the map), ...
in > Geosphere
Published: 01 June 2011
Figure 1. Map of volcanic source area (Sonoma Volcanics, northeast part of the map), and proximal outlying tephra sample localities in sedimentary deposits, within the greater San Francisco Bay area. Geologic map base from Jennings (1977) and Saucedo et al. (2000) . Explanation of symbols
Image
Map of <b>volcanic</b> source area (<b>Sonoma</b> <b>Volcanics</b>, northeast part of the map), ...
in > Geosphere
Published: 01 June 2011
Figure 1. Map of volcanic source area (Sonoma Volcanics, northeast part of the map), and proximal outlying tephra sample localities in sedimentary deposits, within the greater San Francisco Bay area. Geologic map base from Jennings (1977) and Saucedo et al. (2000) . Explanation of symbols
Image
Folded <b>Sonoma</b> <b>Volcanics</b> in the southwestern part of the <b>volcanic</b> field. Bla...
in > Geosphere
Published: 01 June 2011
Figure 6. Folded Sonoma Volcanics in the southwestern part of the volcanic field. Black lines mark a volcanic breccia that has moderate opposing dips. Red lines show the axis of the plunging fold.
Image
Photograph showing contact between flat-lying <b>Sonoma</b> <b>Volcanics</b> and the east...
in > Geosphere
Published: 01 June 2011
Figure 7. Photograph showing contact between flat-lying Sonoma Volcanics and the east-dipping Petaluma Formation, east of Petaluma. An outlier of Sonoma Volcanics overlying east-dipping Petaluma Formation near this locality was dated as 7.36 Ma by Youngman (1989) . The Petaluma Formation
Journal Article
Journal: Geosphere
Published: 01 June 2011
Geosphere (2011) 7 (3): 658-683.
...Figure 6. Folded Sonoma Volcanics in the southwestern part of the volcanic field. Black lines mark a volcanic breccia that has moderate opposing dips. Red lines show the axis of the plunging fold. ...
FIGURES | View All (10)
Series: Society of Economic Geologists Guidebook Series
Published: 01 January 1993
DOI: 10.5382/GB.16
EISBN: 9781934969694
Series: Society of Economic Geologists Guidebook Series
Published: 01 January 1993
DOI: 10.5382/GB.16
EISBN: 9781934969694
... Abstract Epithermal precious-metal and mercury deposits are present in the Sonoma and Clear Lake volcanic fields of central California and several hot springs in the Clear Lake volcanic field are presently depositing mercury and gold. The deposits and hot springs are associated with late...
Journal Article
Journal: AAPG Bulletin
Published: 01 April 1973
AAPG Bulletin (1973) 57 (4): 769.
... assignments and correlations of some units. Previous workers generally have held that the Merced(?) Formation of Sonoma County interfingers laterally with the Sonoma Volcanics, which in turn unconformably overlie the Petaluma Formation. Age assignments have varied, but most recent workers assign the Merced...
Image
40 AR&#x2F; 39 AR AGES OF TEPHRA LAYERS ERUPTED FROM THE <b>SONOMA</b> <b>VOLCANIC</b> FIELD, ...
in > Geosphere
Published: 01 June 2011
TABLE 8. 40 AR/ 39 AR AGES OF TEPHRA LAYERS ERUPTED FROM THE SONOMA VOLCANIC FIELD, CENTRAL COAST RANGES, CALIFORNIA, OBTAINED IN THIS STUDY, COMPARED TO K-AR AGES OBTAINED IN PREVIOUS STUDIES
Image
Simplified geologic map of the <b>Sonoma</b> <b>volcanic</b> field showing place names ci...
in > Geosphere
Published: 01 June 2011
Figure 2. Simplified geologic map of the Sonoma volcanic field showing place names cited in text. Volcanic geology modified from Saucedo et al. (2002) , Graymer et al. (2006a , 2007 ). Black lines are faults, sense of displacement not shown (modified from Bryant, 2005 ; Graymer et al., 2006b
Image
Simplified geologic map of the <b>Sonoma</b> <b>volcanic</b> field showing location of vo...
in > Geosphere
Published: 01 June 2011
Figure 3. Simplified geologic map of the Sonoma volcanic field showing location of volcanic centers. Volcanic geology and faults as shown on Figure 2 . Volcanic centers: AD—Annadel; AH—Arrowhead; BM—Bismarck Knob; CD—Calistoga Dome field; CS—Cup and Saucer; MG—Mount George; MSH—Mount St. Helena
Series: Society of Economic Geologists Guidebook Series
Published: 01 January 1993
DOI: 10.5382/GB.16
EISBN: 9781934969694
Journal Article
Journal: GSA Bulletin
Published: 01 May 1985
GSA Bulletin (1985) 96 (5): 647-654.
..., Pinnacles Volcanic Formation, Quien Sabe Volcanics, volcanic rocks in the Berkeley Hills, Tolay Volcanics, Sonoma Volcanics, and Clear Lake Volcanics. Dispersion in the age-distance relation is reduced by restoration of inferred offsets on transecting right-lateral fault systems. The offsets include 115 km...
Journal Article
Published: 18 April 2017
Geological Magazine (2017) 155 (6): 1305-1329.
... ). This allochthon is sealed in present-day Nevada by the rhyolitic Koipato Formation volcanism, presumably emplaced by the end of the Sonoma orogeny (Vetz, 2011 ). A minimum age of Anisian (Middle Triassic) can be given to this volcanic formation using geochronology (Vetz, 2011 ) and due to the occurrence...
FIGURES | View All (15)
Journal Article
Journal: Geosphere
Published: 01 June 2011
Geosphere (2011) 7 (3): 599-628.
...Figure 1. Map of volcanic source area (Sonoma Volcanics, northeast part of the map), and proximal outlying tephra sample localities in sedimentary deposits, within the greater San Francisco Bay area. Geologic map base from Jennings (1977) and Saucedo et al. (2000) . Explanation of symbols...
FIGURES | View All (16)
Series: Society of Economic Geologists Guidebook Series
Published: 01 January 1993
DOI: 10.5382/GB.16
EISBN: 9781934969694
...) intermittently over a 76 year period. The Palisade and Silverado mines were the two producers of the district. Precious metals enrichment is associated with northeast-striking, en echelon quartz + chalcedony + adularia vein systems, hosted by flows and pyroclastic rocks of die Tertiary Sonoma Volcanics...
Journal Article
Journal: Geology
Published: 01 March 1987
Geology (1987) 15 (3): 270-273.
... apparently were active during a major episode of Late Triassic arc volcanism, and they constrain the age of the Golconda thrust as pre–latest Triassic. The continuation of the Antler and Sonoma orogenic belts to the Saddlebag Lake pendant means that large strike-slip displacements cannot have occurred...