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Sonoma Volcanics

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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...
Image
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 to Figure 1.
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
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 in this area is the middle part of the formation that is interbedded with the 6.26 Roblar tuff. The Sonoma Volcanics here structurally overlie the younger Petaluma Formation and are therefore out of place.
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
Image
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 to Figure 1.
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 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.
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.
Series: Society of Economic Geologists Guidebook Series
Published: 01 January 1993
DOI: 10.5382/GB.16.07
EISBN: 9781934969694
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)
Series: Society of Economic Geologists Guidebook Series
Published: 01 January 1993
DOI: 10.5382/GB.16
EISBN: 9781934969694
Journal Article
Journal: Geosphere
Published: 01 June 2011
Geosphere (2011) 7 (3): 658–683.
...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...
FIGURES | View All (10)
Series: Society of Economic Geologists Guidebook Series
Published: 01 January 1993
DOI: 10.5382/GB.16.03
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...
Image
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; SG—Sugarloaf Ridge; SL—Stags Leap; SON—Sonoma; WL—Wildlake. Locations of volcanic vents and domes beneath Quaternary deposits are defined on the basis of geophysical data.
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
Image
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). YJFZ—Yellowjacket fault zone. Place name abbreviations: AC—Adobe Canyon; AM—Arrowhead Mountain; BK—Bismarck Knob; BM—Bennett Mountain; CS—Cup and Saucer; CV—Carneros Valley; DM—Diamond Mountain; FV—Franz Valley; GM—Napa Glass Mountain; GV—Green Valley; K—Kenwood; KC—Kortum Canyon; LV—Lovall Valley; MG—Mount George; MH—Mount Hood; MSH—Mount St. Helena; MV—Mount Veeder; P—Palisades; PV—Petaluma Valley; RR—Rector Reservoir; SC—Soda Canyon; SH—Schocken Hill; SL—Stags Leap; TM—Taylor Mountain.
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
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
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...
Series: GSA Memoirs
Published: 27 September 2021
DOI: 10.1130/2021.1217(16)
EISBN: 9780813782171
...), in the northeastern Sonoma volcanics of the Coast Ranges. Distal sites where this tephra has been identified are shown with black circles. At the most northwestern site, in the Pullen Formation, this tephra may have been brought down by streams that, at that time, flowed from farther southeast to the northwest, north...
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Map showing volcanic fields, eruptive centers discussed in the text, and major faults north of San Pablo Bay. The Burdell Mountain and Tolay Volcanics have been correlated across faults of the East Bay fault system (Fig. 1). The Sonoma Volcanics have been subdivided into the western age group (WSV), the eastern age group (ESV), and the northern age group (NSV). The Sears Point–Meacham Hill fold-and-thrust belt is also shown. Locations of stratigraphic columns in the western Sonoma Volcanics: SM—Sonoma Mountain assemblage; SC—Sonoma Creek assemblage; A—Arrowhead Mountain assemblage; BK—Bismarck Knob assemblage; SR—Sugarloaf Ridge assemblage.
Published: 01 June 2011
Figure 3. Map showing volcanic fields, eruptive centers discussed in the text, and major faults north of San Pablo Bay. The Burdell Mountain and Tolay Volcanics have been correlated across faults of the East Bay fault system ( Fig. 1 ). The Sonoma Volcanics have been subdivided into the western
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
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.16.04
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...