ARC/INFO Resultant Description of Coverage
export file Coverage
----------- ----------- --------------------------------
sk-geol.e00 sk-geol/ Polygon and line coverage showing
faults, depositional contacts, and
rock units in the map area.
sk-strc.e00 sk-strc/ Point and line coverage showing
strike and dip information and fold axes.
sk-lnds.e00 sk-lnds/ Point and line coverage showing arrows
indicating landslide directions as well
as the locations of wells and springs
not included in the topographic base map.
ASCII text files, including explanatory text, ARC/INFO key files,
PostScript and PDF plot files, and a ARC Macro Language file for
conversion of ARC export files into ARC coverages:
skmf.ps A PostScript plot file of the pamphlet
containing detailed unit descriptions
and geological information, a description
of the digital files associated with the
publication, plus references cited.
skmf.pdf A PDF version of mamf.ps.
skmf.txt A text-only file containing an unformatted
version of skmf.ps.
import.aml ASCII text file in ARC Macro Language to
convert ARC export files to ARC coverages
in ARC/INFO.
skmap.ps A PostScript plottable file containing
an image of the geologic map and base
maps at a scale of 1:24,000, along with
a simple map key.
skmap.pdf A PDF file containing an image of the
geologic map and base maps at a scale
of 1:24,000, along with a simple map key.
Base maps
Online Links:
| Value | Definition |
|---|---|
| Qaf | Artificial fill |
| Qb | Basin deposits |
| Qal | Alluvial deposits, undivided |
| Qyf | Younger flood-plain deposits |
| Qof | Older flood-plain deposits |
| Qc | Colluvium |
| Qcf | Abandoned channel fill deposits |
| Qls | Landslide deposits |
| Qt | Terrace deposits, undivided |
| Qoe | Older eolian deposits |
| Qch | Alluvial fan deposits of Chualar |
| Qp | Alluvial fan deposits of Placentia |
| Qgl | Alluvial fan deposits of Gloria |
| QTc | Continental deposits, undivided |
| Tsm | Santa Margarita Sandstone |
| Tmd | Monterey Formation, diatomite |
| Tm | Monterey Formation, porcelinite |
| Tus | Unnamed sandstone |
| Tuss | Unnamed sandstone, undifferentiated |
| Tuc | Unnamed conglomerate |
| Kgd | Granodiorite of Cachagua of Ross |
| Kqm | Garnetiferous quartz monzonite of Pine Canyon of Ross |
| Khqd | Hornblende-biotite quartz diorite and diorite of Corral de Tierra |
| msc | Schist of the Sierra de Salinas of Ross |
| ms | Quartzofeldspathic rocks |
| ml | Marble |
| water | water |
| Value | Definition |
|---|---|
| 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. |
| 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 1.25 mm at map scale (1:24,000) or within about 30 meters on the ground. |
| contact, inferred, queried | 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 1.25 mm at map scale (1:24,000) or within about 30 meters on the ground. The existence of the contact is inferred from structural and stratigraphic relationships observed elsewhere. |
| contact, sed_terrace, approx. located | Inner edge of a terrace deposit at the break in slope on the landward side of either a coastal terrace (shoreline angle) or a stream terrace. 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 1.25 mm at map scale (1:24,000) or within about 30 meters on the ground. |
| contact, sed_terrace, certain | Inner edge of a terrace deposit at the break in slope on the landward side of either a coastal terrace (shoreline angle) or a stream terrace. 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 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 1.25 mm at map scale (1:24,000) or within about 30 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 2.5 mm at map scale (1:24,000) or within about 60 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 2.5 mm at map scale (1:24,000) or within about 60 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. |
| Value | Definition |
|---|---|
| ash bedding | Ash bed too thin to appear on map. |
| bedding | Originally horizontal sedimentary layers were observed at this point. |
| 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. |
| vert foliation | Vertical metamorphic foliation was observed at this point. |
| Range of values | |
|---|---|
| Minimum: | 0 |
| Maximum: | 90 |
| Units: | degrees |
| Resolution: | 1 |
| Range of values | |
|---|---|
| Minimum: | 0 |
| Maximum: | 359 |
| Units: | degrees |
| Resolution: | 1 |
| Value | Definition |
|---|---|
| contact, certain | Boundary between two mapped units that retains the original depositional or intrusive relationship (i.e. not faulted). The contact has been observed, so it is well-located as described in Positional_Accuracy. |
| f.a., anticline, certain | The surface trace of the axis of an anticline. The axis is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 2.5 mm at map scale (1:24,000) or within about 60 meters on the ground. |
| f.a., anticline, concealed | The surface trace of the axis of an anticline. The axis 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 2.5 mm at map scale (1:24,000) or within about 60 meters on the ground. |
| 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 3.75 mm at map scale (1:24, 000) or within about 90 meters on the ground. |
| f.a., syncline, certain | The surface trace of the axis of a syncline. The axis is not well-located as described in Positional_Accuracy, but the location is constrained to be within about 2.5 mm at map scale (1:24,000) or within about 60 meters on the ground. |
| f.a., syncline, concealed | The surface trace of the axis of a syncline. The axis 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 2.5 mm at map scale (1:24,000) or within about 60 meters on the ground. |
| f.a., syncline, approx. located | The surface trace of the axis of a 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 3.75 mm at map scale (1:24,000) or within about 90 meters on the ground. |
| Value | Definition |
|---|---|
| arrowhead | The plunging end of a fold axis. |
| 0 | Not a plunging fold axis. |
| Value | Definition |
|---|---|
| oil well | Dry hole drilled for hydrocarbon exploration |
| spring | Spring |
| water well | Water well |
David L. Wagner of the California Division of Mines and Geology ( CDMG) provided Clark and Rosenberg with funding for their 1998 field mapping. Wagner also coordinated the work of Sarah E. Watkins (CDMG), who digitized the geologic map for incorporation into the geologic map of the Monterey 1:100,000-scale quadrangle, which is in preparation.
Andrei Sarna-Wojcicki (USGS) analyzed and correlated Miocene ash beds from the quadrangle. Charles Powell, II (USGS) identified and interpreted mollusks collected from the quadrangle by Brabb and Clark. He also examined and interpreted mollusks at the California Academy of Science collected by Bowen and at the Museum of Paleontology, University of California, Berkeley that had been collected and reported by Herold (1935). Kristin McDougall (USGS) identified and interpreted Miocene foraminifers. Victoria Langenheim (USGS) and Robert Jachens (USGS) kindly provided unpublished gravity and aeromagnetic data with an interpretation of regional faulting. Special thanks go to Richard R. Thorup for sharing his extensive knowledge of the geology of the quadrangle.
Heather V. Goss (USGS and Environmental Careers Organization) added a structure layer, including strikes and dips and fold axes, to the digital map file, annotated and formatted the map to conform to USGS publication standards, and made corrections to the map after technical reviews. She wrote the metadata for the digital file, formatted the text to conform to USGS publication standards, and changed and added information after technical review.
This database and accompanying plot files depict the distribution of geologic materials and structures at a scale of 1:24,000. 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 accurately identify or delineate landslides in the region.
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 1:24,000 means that higher resolution information is not present in the dataset. Plotting at scales larger than 1:24,000 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.
Commercial entities named in the texts of this report are cited for descriptive purposes, not to constitute an endorsement of those products.
| Data format: | ARCE (version 7.x) Size: 0.5 |
|---|---|
| Network links: |
http://pubs.usgs.gov/mf/2001/2349/mf2349c.t.gz |