Online Links:
| Value | Definition |
|---|---|
| H2O | water |
| Jgb | Gabbro |
| Jsv | Siliceous volcanic rocks and keratophyre |
| KJf | Franciscan complex, undivided |
| KJv | Unnamed volcanic rocks (Cretaceous or older) |
| Ka | Conglomerate of strata of Anchor Bay (Wentworth, 1968) |
| Kgr | Granitic rocks of Montara Mountain |
| Kpp | Pigeon Point Formation |
| Kqd | Granitic rocks of Ben Lomond Mountain |
| Ks | Unnamed sandstone and shale (Cretaceous(?)) |
| Ksh | Unnamed shale (Upper Cretaceous) |
| QTm | Merced Formation |
| QTsc | Santa Clara Formation |
| QTsl | Santa Clara Formation, lake beds |
| Qal | Alluvium (Holocene) |
| Qbs | Beach sand (Holocene) |
| Qcl | Colluvium (Holocene) |
| Qhaf | Alluvial fan and fluvial deposits (Holocene) |
| Qhaf1 | Younger alluvial fan deposits (Holocene) |
| Qhasc | Artificial stream channels |
| Qhb | Basin deposits (Holocene) |
| Qhbm | Bay mud (Holocene) |
| Qhbs | Basin deposits, salt affected (Holocene) |
| Qhfp | Flood-plain deposits (Holocene) |
| Qhl | Natural levee deposits (Holocene) |
| Qhsc | Stream channel deposits (Holocene) |
| Qls | Landslide deposits |
| Qmt | Marine terrace deposits (Pleistocene) |
| Qof | Coarse-grained older alluvial fan and stream terrace deposits (Pleistocene) |
| Qpaf | Alluvial fan and fluvial deposits (Pleistocene) |
| Qpaf1 | Alluvial terrace deposits (Pleistocene) |
| Qpoaf | Older alluvial fan deposits (Pleistocene) |
| Qs | Sand dune and beach deposits (Holocene) |
| Qyf | Younger (inner) alluvial fan deposits (Holocene) |
| Qyfo | Younger (outer) alluvial fan deposits (Holocene) |
| Tb | Butano Sandstone |
| Tbl | Butano Sandstone, lower conglomerate and sandstone member |
| Tblc | Butano Sandstone, lower member, conglomerate |
| Tblc? | Butano Sandstone, lower member, conglomerate, identification uncertain |
| Tbm | Butano Sandstone, middle siltstone member |
| Tbs | Butano Sandstone, shale member |
| Tbu | Butano Sandstone, upper sandstone member |
| Tl | Locatelli Formation |
| Tla | Lambert Shale |
| Tlad | Ladera Sandstone |
| Tlo | Lompico Sandstone |
| Tls | Lambert Shale and San Lorenzo Formation, undivided |
| Tlss | Locatelli Formation, sandstone member |
| Tm | Monterey Formation |
| Tmb | Mindego Basalt and related volcanic rocks |
| Tms | Unnamed marine sandstone and shale (Miocene) |
| Tp | Purisima Formation |
| Tpl | Purisima Formation, Lobitos Mudstone member |
| Tpm | Page Mill Basalt |
| Tpp | Purisima Formation, Pomponio Mudstone member |
| Tpsg | Purisima Formation, San Gregorio Sandstone member |
| Tpt | Purisima Formation, Tahana member |
| Tptu | Purisima Formation, Tunitas Sandstone member |
| Tsc | Santa Cruz Mudstone |
| Tsl | San Lorenzo Formation |
| Tsm | Santa Margarita Sandstone |
| Tsr | San Lorenzo Formation, Rices Mudstone member |
| Tst | San Lorenzo Formation, Twobar Shale member |
| Tu | Unnamed sedimentary rocks (Eocene(?)) |
| Tuv | Unnamed sedimentary and volcanic rocks (Miocene and Oligocene) |
| Tvq | Vaqueros Sandstone |
| Tw | Whiskey Hill Formation |
| Tws | Whiskey Hill Formation, shale member |
| Tz | Zayante Sandstone |
| af | Artificial fill |
| alf | Artificial levee fill |
| db | Diabase and gabbro (Jurassic(?)) |
| fc | Franciscan complex, chert |
| fg | Franciscan complex, greenstone |
| fh | Franciscan complex, argillite |
| fl | Franciscan complex, limestone |
| fm | Franciscan complex, metamorphic rocks |
| fs | Franciscan complex, sandstone |
| fsr | Franciscan complex, sheared rock (melange) |
| ga | Granitic rocks of Ben Lomond Mountain, granite and alaskite |
| gd | Gneissic granodiorite (Mesozoic or Paleozoic) |
| hcg | Granitic rocks of Ben Lomond Mountain, hornblende-cummingtonite gabbro |
| m | Marble (Mesozoic or Paleozoic) |
| sch | Metasedimentary rocks (Mesozoic or Paleozoic) |
| sp | Serpentinite (Cretaceous and/or Jurassic) |
| Value | Definition |
|---|---|
| contact, approx. located | Boundary between two mapped units that retains the original depositional or intrusive relationship (i.e. not faulted). The contact has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 2 mm at map scale (1:100,000) or within about 200 meters on the ground. |
| contact, certain | Boundary between two mapped units that retains the original depositional or intrusive relationship (i.e. not faulted). The contact has been observed or is closely constrained, so it is well-located as described in Positional_Accuracy. |
| fault, approx. located | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The contact has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 2 mm at map scale (1:100,000) or within about 200 meters on the ground. |
| fault, certain | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The fault has been observed or is closely constrained, so it is well-located as described in Positional_Accuracy. |
| fault, concealed | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The fault is obscured by overlying mapped units, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 5 mm at map scale (1:100,000) or within about 500 meters on the ground. |
| fault, concealed, queried | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The fault is obscured by overlying mapped units, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 10 mm at map scale (1:100,000) or within about 1000 meters on the ground. |
| fault, inferred | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The fault has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 5 mm at map scale (1:100,000) or within about 500 meters on the ground. The existence of the fault is inferred from structural and stratigraphic relationships observed elsewhere. |
| fault, inferred, queried | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The fault has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 10 mm at map scale (1:100,000) or within about 1000 meters on the ground. The existence of the fault is inferred from structural and stratigraphic relationships observed elsewhere. |
| map boundary, | Edge of the mapped area. Used primarily to bound polygons at the edge of the map database. The location of the boundary is well located as described in Positional_Accuracy |
| reverse fault, approx. located | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced reverse offset between the rock bodies on either side of the fault. The contact has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 2 mm at map scale (1:100,000) or within about 200 meters on the ground. |
| reverse fault, certain | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced reverse offset between the rock bodies on either side of the fault. The fault has been observed or is closely constrained, so it is well-located as described in Positional_Accuracy. |
| reverse fault, concealed | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced reverse offset between the rock bodies on either side of the fault. The fault is obscured by overlying mapped units, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 5 mm at map scale (1:100,000) or within about 500 meters on the ground. |
| scratch boundary, certain | An arbitrary line with no geologic or geographic significance. Used primarily to divide polygons that would otherwise have more vertices than allowed by Arc/Info. |
| thrust fault, approx. located | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced thrust offset between the rock bodies on either side of the fault. The contact has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 2 mm at map scale (1:100,000) or within about 200 meters on the ground. |
| thrust fault, certain | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced thrust offset between the rock bodies on either side of the fault. The fault has been observed or is closely constrained, so it is well-located as described in Positional_Accuracy. |
| thrust fault, concealed | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced thrust offset between the rock bodies on either side of the fault. The fault is obscured by overlying mapped units, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 5 mm at map scale (1:100,000) or within about 500 meters on the ground. |
| thrust fault, concealed, queried | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced thrust offset between the rock bodies on either side of the fault. The fault is obscured by overlying mapped units, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 10 mm at map scale (1:100,000) or within about 1000 meters on the ground. The existence of this fault has been inferred from probable stratigraphic and structural relationships observed at a regional scale. |
| water boundary | The edge of a mapped body of water. This line is derived from the base map, and therefore is well-located as described in Positional_Accuracy. |
| water boundary, | The edge of a mapped body of water. This line is derived from the base map, and therefore is well-located as described in Positional_Accuracy. |
| water boundary, certain | The edge of a mapped body of water. This line is derived from the base map, and therefore is well-located as described in Positional_Accuracy. |
| Value | Definition |
|---|---|
| approx bedding | Originally horizontal sedimentary layers were observed at this point. Because of poor exposure, weathering, indistinct layering, or some other factor, only the approximate orientation of the layers was measured. |
| bedding | Originally horizontal sedimentary layers were observed at this point. |
| bedding w/tops | Originally horizontal sedimentary layers were observed at this point. In addition, a geopedal indicator was observed that showed the beds were upright. |
| flat bedding | Sedimentary layers that retain their original horizontal position were observed at this point. |
| foliation | Metamorphic foliation was observed at this point. |
| ot bedding | Originally horizontal sedimentary layers were observed at this point. Evidence that the beds are overturned was observed, although that observation may not have been made at this point. |
| vert bedding | Originally horizontal sedimentary layers were observed at this point. These layers are now vertical. |
| Range of values | |
|---|---|
| Minimum: | 0 |
| Maximum: | 90 |
| Units: | degrees |
| Resolution: | 1 |
| Range of values | |
|---|---|
| Minimum: | 0 |
| Maximum: | 359 |
| Units: | degrees |
| Resolution: | 1 |
| Value | Definition |
|---|---|
| f.a., anticline, approx. located | The surface trace of the axis of an anticline. The axis has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 2 mm at map scale (1:100,000) or within about 200 meters on the ground. |
| f.a., anticline, certain | The surface trace of the axis of an anticline. The axis has been observed or is closely constrained, so it is well-located as described in Positional_Accuracy. |
| f.a., anticline, concealed | The surface trace of the axis of an anticline. The axis is obscured by overlying unfolded mapped units or water, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 5 mm at map scale (1:100,000) or within about 500 meters on the ground. |
| f.a., syncline, approx. located | The surface trace of the axis of an syncline. The axis has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 2 mm at map scale (1:100,000) or within about 200 meters on the ground. |
| f.a., syncline, certain | The surface trace of the axis of an syncline. The axis has been observed or is closely constrained, so it is well-located as described in Positional_Accuracy. |
| f.a., syncline, concealed | The surface trace of the axis of an syncline. The axis is obscured by overlying unfolded mapped units or water, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 5 mm at map scale (1:100,000) or within about 500 meters on the ground. |
| f.a., syncline, inferred, queried | The surface trace of the axis of an syncline. The axis has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 10 mm at map scale (1:100,000) or within about 1000 meters on the ground. The existence of the fold is inferred from structural and stratigraphic relationships observed elsewhere. |
| Value | Definition |
|---|---|
| 'Ano Nuevo' | Ano Nuevo 7.5' quadrangle |
| 'Big Basin' | Big Basin 7.5' quadrangle |
| 'Castle Rock Ridge' | Castle Rock Ridge 7.5' quadrangle |
| 'Franklin Point' | Franklin Point 7.5' quadrangle |
| 'Half Moon Bay' | Half Moon Bay 7.5' quadrangle |
| 'La Honda' | La Honda 7.5' quadrangle |
| 'Mindego Hill' | Mindego Hill 7.5' quadrangle |
| 'Mountain View' | Mountain View 7.5' quadrangle |
| 'Palo Alto' | Palo Alto 7.5' quadrangle |
| 'Pigeon Point' | Pigeon Point 7.5' quadrangle |
| 'San Gregorio' | San Gregorio 7.5' quadrangle |
| 'Santa Cruz' | Santa Cruz 7.5' quadrangle |
| Cupertino | Cupertino 7.5' quadrangle |
| Davenport | Davenport 7.5' quadrangle |
| Felton | Felton 7.5' quadrangle |
| Woodside | Woodside 7.5' quadrangle |
| Value | Definition |
|---|---|
| map boundary | Edge of the mapped area. The location of the boundary is well located as described in Positional_Accuracy |
| quad | Edge of a USGS 7.5-minute quadrangle in the map area. This line is derived from a 7.5-minute grid generated from latitude and longitude values and therefore should be precisely located. |
| Value | Definition |
|---|---|
| fault, approx. located | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The contact has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 2 mm at map scale (1:100,000) or within about 200 meters on the ground. |
| fault, certain | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The fault has been observed or is closely constrained, so it is well-located as described in Positional_Accuracy. |
| fault, concealed | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The fault is obscured by overlying mapped units, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 5 mm at map scale (1:100,000) or within about 500 meters on the ground. |
| fault, concealed, queried | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The fault is obscured by overlying mapped units, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 10 mm at map scale (1:100,000) or within about 1000 meters on the ground. |
| fault, inferred | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The fault has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 5 mm at map scale (1:100,000) or within about 500 meters on the ground. The existence of the fault is inferred from structural and stratigraphic relationships observed elsewhere. |
| fault, inferred, queried | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The fault has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 10 mm at map scale (1:100,000) or within about 1000 meters on the ground. The existence of the fault is inferred from structural and stratigraphic relationships observed elsewhere. |
| reverse fault, approx. located | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced reverse offset between the rock bodies on either side of the fault. The contact has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 2 mm at map scale (1:100,000) or within about 200 meters on the ground. |
| reverse fault, certain | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced reverse offset between the rock bodies on either side of the fault. The fault has been observed or is closely constrained, so it is well-located as described in Positional_Accuracy. |
| reverse fault, concealed | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced reverse offset between the rock bodies on either side of the fault. The fault is obscured by overlying mapped units, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 5 mm at map scale (1:100,000) or within about 500 meters on the ground. |
| thrust fault, approx. located | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced thrust offset between the rock bodies on either side of the fault. The contact has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 2 mm at map scale (1:100,000) or within about 200 meters on the ground. |
| thrust fault, certain | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced thrust offset between the rock bodies on either side of the fault. The fault has been observed or is closely constrained, so it is well-located as described in Positional_Accuracy. |
| thrust fault, concealed | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced thrust offset between the rock bodies on either side of the fault. The fault is obscured by overlying mapped units, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 5 mm at map scale (1:100,000) or within about 500 meters on the ground. |
| thrust fault, concealed, queried | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced thrust offset between the rock bodies on either side of the fault. The fault is obscured by overlying mapped units, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 10 mm at map scale (1:100,000) or within about 1000 meters on the ground. The existence of this fault has been inferred from probable stratigraphic and structural relationships observed at a regional scale. |
| Value | Definition |
|---|---|
| Ben Lomond fault | Segment belongs to the Ben Lomond fault |
| Berrocal fault | Segment belongs to the Berrocal fault |
| Butano fault | Segment belongs to the Butano fault |
| La Honda fault | Segment belongs to the La Honda fault |
| Monta Vista fault | Segment belongs to the Monta Vista fault |
| Pilarcitos fault | Segment belongs to the Pilarcitos fault |
| Pulgas fault | Segment belongs to the Pulgas fault |
| San Andreas fault zone | Segment belongs to the San Andreas fault zone |
| San Gregorio fault | Segment belongs to the San Gregorio fault |
| Seal Cove fault | Segment belongs to the Seal Cove fault |
| Woodhaven fault | Segment belongs to the Woodhaven fault |
| Zayante fault | Segment belongs to the Zayante fault |
| none | Segment belongs to an unnamed fault |
| Value | Definition |
|---|---|
| Jgb | Gabbro |
| Jsv | Siliceous volcanic rocks and keratophyre |
| KJf | Franciscan complex, undivided |
| KJv | Unnamed volcanic rocks (Cretaceous or older) |
| Ka | Conglomerate of strata of Anchor Bay (Wentworth, 1968) |
| Kgr | Granitic rocks of Montara Mountain |
| Kpp | Pigeon Point Formation |
| Kqd | Granitic rocks of Ben Lomond Mountain |
| Ks | Unnamed sandstone and shale (Cretaceous(?)) |
| Ksh | Unnamed shale (Upper Cretaceous) |
| QTm | Merced Formation |
| QTsc | Santa Clara Formation |
| QTsl | Santa Clara Formation, lake beds |
| Qal | Alluvium (Holocene) |
| Qbs | Beach sand (Holocene) |
| Qcl | Colluvium (Holocene) |
| Qhaf | Alluvial fan and fluvial deposits (Holocene) |
| Qhaf1 | Younger alluvial fan deposits (Holocene) |
| Qhasc | Artificial stream channels |
| Qhb | Basin deposits (Holocene) |
| Qhbm | Bay mud (Holocene) |
| Qhbs | Basin deposits, salt affected (Holocene) |
| Qhfp | Flood-plain deposits (Holocene) |
| Qhl | Natural levee deposits (Holocene) |
| Qhsc | Stream channel deposits (Holocene) |
| Qls | Landslide deposits |
| Qmt | Marine terrace deposits (Pleistocene) |
| Qof | Coarse-grained older alluvial fan and stream terrace deposits (Pleistocene) |
| Qpaf | Alluvial fan and fluvial deposits (Pleistocene) |
| Qpaf1 | Alluvial terrace deposits (Pleistocene) |
| Qpoaf | Older alluvial fan deposits (Pleistocene) |
| Qs | Sand dune and beach deposits (Holocene) |
| Qyf | Younger (inner) alluvial fan deposits (Holocene) |
| Qyfo | Younger (outer) alluvial fan deposits (Holocene) |
| Tb | Butano Sandstone |
| Tbl | Butano Sandstone, lower conglomerate and sandstone member |
| Tblc | Butano Sandstone, lower member, conglomerate |
| Tbm | Butano Sandstone, middle siltstone member |
| Tbs | Butano Sandstone, shale member |
| Tbu | Butano Sandstone, upper sandstone member |
| Tl | Locatelli Formation |
| Tla | Lambert Shale |
| Tlad | Ladera Sandstone |
| Tlo | Lompico Sandstone |
| Tls | Lambert Shale and San Lorenzo Formation, undivided |
| Tlss | Locatelli Formation, sandstone member |
| Tm | Monterey Formation |
| Tmb | Mindego Basalt and related volcanic rocks |
| Tms | Unnamed marine sandstone and shale (Miocene) |
| Tp | Purisima Formation |
| Tpl | Purisima Formation, Lobitos Mudstone member |
| Tpm | Page Mill Basalt |
| Tpp | Purisima Formation, Pomponio Mudstone member |
| Tpsg | Purisima Formation, San Gregorio Sandstone member |
| Tpt | Purisima Formation, Tahana member |
| Tptu | Purisima Formation, Tunitas Sandstone member |
| Tsc | Santa Cruz Mudstone |
| Tsl | San Lorenzo Formation |
| Tsm | Santa Margarita Sandstone |
| Tsr | San Lorenzo Formation, Rices Mudstone member |
| Tst | San Lorenzo Formation, Twobar Shale member |
| Tu | Unnamed sedimentary rocks (Eocene(?)) |
| Tuv | Unnamed sedimentary and volcanic rocks (Miocene and Oligocene) |
| Tvq | Vaqueros Sandstone |
| Tw | Whiskey Hill Formation |
| Tws | Whiskey Hill Formation, shale member |
| Tz | Zayante Sandstone |
| af | Artificial fill |
| alf | Artificial levee fill |
| db | Diabase and gabbro (Jurassic(?)) |
| fc | Franciscan complex, chert |
| fg | Franciscan complex, greenstone |
| fh | Franciscan complex, argillite |
| fl | Franciscan complex, limestone |
| fm | Franciscan complex, metamorphic rocks |
| fs | Franciscan complex, sandstone |
| fsr | Franciscan complex, sheared rock (melange) |
| ga | Granitic rocks of Ben Lomond Mountain, granite and alaskite |
| gd | Gneissic granodiorite (Mesozoic or Paleozoic) |
| hcg | Granitic rocks of Ben Lomond Mountain, hornblende-cummingtonite gabbro |
| m | Marble (Mesozoic or Paleozoic) |
| sch | Metasedimentary rocks (Mesozoic or Paleozoic) |
| sp | Serpentinite (Cretaceous and/or Jurassic) |
| Value | Definition |
|---|---|
| box, | Edge of a box in the correlation chart |
| bracket, | Bracket line in the correlation chart to delineate age categories |
| leader, | Leader line in the correlation chart to enable labeling of small boxes |
| scratch boundary, | Non-drawing line in the correlation chart to ensure annotation is entirely within the map boundary |
| Value | Definition |
|---|---|
| water | Areas mapped as water. The sources of the water areas are the USGS Palo Alto 30' X 60' topographic quadrangle and various 7.5' quadrangles within the map area. |
| Range of values | |
|---|---|
| Minimum: | 1 |
| Maximum: | 30 |
| Value | Definition |
|---|---|
| contact, certain | The boundary between regions within which different sources of data were used to supplement new mapping by the authors. The sources are delineated in Source_Information as well as Sheet 2 plotfiles maexpl.ps and maexpl.pdf. This line is not well-located as described in Positional_Accuracy, and is included for general reference only. |
| leader | A line included for plotting purposes only to allow the labeling of some small areas. This line is not well-located as described in Positional_Accuracy, and is included for general reference only. |
| map boundary, | The edge of the index map area. |
| tic | A line included for plotting purposes only to allow the labeling latitude and longitude in plots. This line is well-located as described in Positional_Accuracy, but is included for general reference only. |
| water boundary, | The edge of a mapped body of water. This line is not well-located as described in Positional_Accuracy, and is included for general reference only. |
| Value | Definition |
|---|---|
| 'Butano Ridge Assemblage' | Outcrop area of the Butano Ridge Assemblage |
| 'Mindego Hill Assemblage' | Outcrop area of the Mindego Hill Assemblage |
| 'Montara Mountain Assemblage' | Outcrop area of the Montara Mountain Assemblage |
| 'Pacifica Assemblage' | Outcrop area of the Pacifica Assemblage |
| 'Pigeon Point Assemblage' | Outcrop area of the Pigeon Point Assemblage |
| 'Portola Valley Assemblage' | Outcrop area of the Portola Valley Assemblage |
| 'Quaternary cover' | Area where the bedrock is obscured by continuous Quaternary cover. Underlying assemblages unknown. |
| 'Santa Cruz Assemblage' | Outcrop area of the Santa Cruz Assemblage |
| 'Sky Londa Assemblage' | Outcrop area of the Sky Londa Assemblage |
| 'Woodside Assemblage' | Outcrop area of the Woodside Assemblage |
| 'artificial fill' | Area where the bedrock is obscured by continuous artificial fill. Underlying assemblages unknown. |
| H2O | Area mapped as water. |
| Value | Definition |
|---|---|
| contact, approx. located | Boundary between two mapped units that retains the original depositional or intrusive relationship (i.e. not faulted). The contact has not been observed, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 2 mm at map scale (1:100,000) or within about 200 meters on the ground. |
| fault, certain | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The fault has been observed, so it is well-located as described in Positional_Accuracy. |
| fault, concealed | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The fault is obscured by overlying mapped units, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 5 mm at map scale (1:100,000) or within about 500 meters on the ground. |
| fault, concealed, queried | Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset between the rock bodies on either side of the fault. The fault is obscured by overlying mapped units, so it is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 10 mm at map scale (1:100,000) or within about 1000 meters on the ground. |
| map boundary, | Edge of the mapped area. Used primarily to bound polygons at the edge of the map database. The location of the boundary is well located as described in Positional_Accuracy |
| scratch boundary, | An arbitrary line with no geologic significance. Used primarily to divide polygons that would otherwise have more vertices than allowed by Arc/Info. |
| tic | A line included for plotting purposes only to allow the labeling latitude and longitude in plots. This line is well-located as described in Positional_Accuracy, but is included for plotting purposes only. |
| water boundary, | The edge of a mapped body of water. This line is derived from the base map, and therefore is well-located as described in Positional_Accuracy. |
We are grateful to the following U.S. Geological Survey paleontologists who have examined our fossils and provided ages necessary to establish the stratigraphic sequence and structure: David Bukry (Cretaceous and Tertiary nannoplankton), Kristin McDougall (Tertiary foraminifers), William Sliter (deceased--Cretaceous and Eocene foraminifers), John Barron (Tertiary diatoms), Charles Powell II (Tertiary mollusks), and Bonita Murchey (Mesozoic radiolaria). We are also very grateful to managers and staff of Chevron, EXXON, UNOCAL, ARCO, and Shell Petroleum Companies who have provided reports and maps, and picked slides and residues for about 25,000 microfossil localities in the San Francisco Bay Region. We are grateful to Tracey Felger, who made the original scan and a preliminary edit of author materials; to Judy Mariant, who did additional editing and tagging of lines; and to Dominique Garnier, who digitized many of the bedding attitudes. Carl Wentworth kindly provided advice on digitizing and editing procedures. Ed Helley provided materials and advice on Quaternary units.
This database and accompanying plot files depict the distribution of geologic materials and structures at a regional (1:100,000) scale. The report is intended to provide geologic information for the regional study of materials properties, earthquake shaking, landslide potential, mineral hazards, seismic velocity, and earthquake faults. In addition, the report contains new information and interpretations about the regional geologic history and framework. However, the regional scale of this report does not provide sufficient detail for site development purposes. In addition, this map does not take the place of fault-rupture hazard zones designated by the California State Geologist (Hart and Bryant, 1997). Similarly, the database cannot be used to identify or delineate landslides in the region.
Online Links:
Online Links:
Online Links:
Are there legal restrictions on access or use of the data?Access_Constraints: None
Use_Constraints:Uses of this digital geologic map should not violate the spatial resolution of the data. Although the digital form of the data removes the constraint imposed by the scale of a paper map, the detail and accuracy inherent in map scale are also present in the digital data. The fact that this database was edited for a scale of 1:100,000 means that higher resolution information is not present in the dataset. Plotting at scales larger than 1:100,000 will not yield greater real detail, although it may reveal fine-scale irregularities below the intended resolution of the database. Similarly, where this database is used in combination with other data of higher resolution, the resolution of the combined output will be limited by the lower resolution of these data.
Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this publication has been subjected to rigorous review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use.
| Data format: | Printable versions of the map in format EPSF (version 1.2) |
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| Network links: |
http://pubs.usgs.gov/mf/2000/mf-2332/m2332ps.tgz |
| Data format: | Printable versions of the map in format PDF (version 3.0) |
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| Network links: |
http://pubs.usgs.gov/mf/2000/mf-2332/m2332pdf.tgz |
| Data format: | Geologic units and structural features with base map information in format ARCE (version 7.2.1) |
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| Network links: |
http://pubs.usgs.gov/mf/2000/mf-2332/m2332db.tgz |