Citation:
Citation_Information:
Originator: Douglas M. Morton
Originator: Jonathan C. Matti
Publication_Date: 2001
Title:
Geologic Map of the Cucamonga Peak 7.5' quadrangle, San Bernardino County, California
Edition: Version 1.0
Geospatial_Data_Presentation_Form: vector digital data
Series_Information:
Series_Name: U.S. Geological Survey Open-File Report
Issue_Identification: 01-311
Publication_Information:
Publication_Place: Menlo Park, California
Publisher: U.S. Geological Survey
Online_Linkage: http://pubs.usgs.gov/of/2001/0311/
Description:
Abstract:
This data set maps and describes the geology of the Cucamonga Peak 7.5' quadrangle,
San Bernardino County, California. Created using Environmental Systems Research
Institute's ARC/INFO software, the database consists of the following items: (1) a
map coverage containing geologic contacts and units, (2) a coverage containing
site-specific structural data, (3) a coverage containing geologic-unit label leaders
and their associated attribute tables for geologic units (polygons), contacts
(arcs), and site-specific data (points). In addition, the data set includes the
following graphic and text products: (1) A PostScript graphic plot-file containing
the geologic map, topography, cultural data, a Correlation of Map Units (CMU)
diagram, a Description of Map Units (DMU), an index map, a regional geologic and
structure map, and a key for point and line symbols; (2) PDF files of this Readme
(including the metadata file as an appendix) and the graphic produced by the
PostScript plot file.
The Cucamonga Peak quadrangle includes part of the boundary between two major
physiographic provinces of California, the Transverse Ranges Province to the north
and the Peninsular Ranges Province to the south. The north part of the quadrangle is
in the eastern San Gabriel Mountains, and the southern part includes an extensive
Quaternary alluvial-fan complex flanking the upper Santa Ana River valley, the
northernmost part of the Peninsular Ranges Province.
Thrust faults of the active Cucamonga Fault zone along the the south margin of the
San Gabriel Mountains are the rejuvenated eastern terminus of a major old fault zone
that bounds the south side of the western and central Transverse Ranges (Morton and
Matti, 1993). Rejuvenation of this old fault zone, including the Cucamonga Fault
zone, is apparently in response to compression in the eastern San Gabriel Mountains
resulting from initiation of right-lateral slip on the San Jacinto Fault zone in the
Peninsular Ranges. Within the northern part of the quadrangle are several
arcuate-in-plan faults that are part of an antiformal, schuppen-like fault complex of
the eastern San Gabriel Mountains. Most of these arcuate faults are reactivated and
deformed older faults that probably include the eastern part of the San Gabriel Fault.
The structural grain within the San Gabriel Mountains, as defined by basement rocks,
is generally east striking. Within the Cucamonga Peak quadrangle, these basement
rocks include a Paleozoic schist and gneiss sequence which occurs as large,
continuous and discontinuous bodies intruded by Cretaceous granitic rocks. Most of
the granitic rocks are of tonalitic composition, and many are mylonitic. South of
the granitic rocks is a comple assemblage of Proterozoic(?) metamorphic rocks, at
least part of which is metasedimentary. This assemblage is intruded by Cretaceous
tonalite on its north side, and by charnockitic rocks near the center of the mass.
The charnockitic rocks are in contact with no other Cretaceous granitic rocks.
Consequently, their relative position in the intrusive sequence is unknown. The
Proterozoic(?) assemblage was metamorphosed to upper amphibolite and lower granulite
grade, and subsequently to a lower metamorphic grade. It is also intensely deformed
by mylonitization characterized by an east-striking, north-dipping foliation, and by
a pronounced subhorizontal lineation that plunges shallowly east and west.
The southern half of the quadrangle is dominated by extensive, symmetrical
alluvial-fan complexes, particularly two emanating from Day and Deer Canyons. Other
Quaternary units ranging from early Pleistocene to recent are mapped, and represent
alluvial-fan, landslide, talus, and wash environments.
The geologic map database contains original U.S. Geological Survey data generated by
detailed field observation and by interpretation of aerial photographs. This digital
Open-File map supercedes an older analog Open-File map of the quadrangle, and
includes extensive new data on the Quaternary deposits, and revises some fault and
bedrock distribution within the San Gabriel Mountains. The digital map was compiled
on a base-stable cronoflex copy of the Cucamonga Peak 7.5' topographic base and then
scribed. This scribe guide was used to make a 0.007 mil blackline clear-film, from
which lines and point were hand digitized. Lines, points, and polygons were
subsequently edited at the USGS using standard ARC/INFO commands. Digitizing and
editing artifacts significant enough to display at a scale of 1:24,000 were
corrected. Within the database, geologic contacts are represented as lines (arcs),
geologic units as polygons, and site-specific data as points. Polygon, arc, and
point attribute tables (.pat, .aat, and .pat, respectively) uniquely identify each
geologic datum.
Purpose:
The data set for the Cucamonga Peak 7.5' quadrangle has been prepared under the U.S.
Geological Survey Southern California Areal Mapping Project (SCAMP) as part of an
ongoing effort to develop a regional geologic framework of southern California, and to
utilize a Geographical Information System (GIS) format to create regional digital
geologic databases. These regional databases are being developed as contributions to
the National Geologic Map Database of the National Cooperative Geologic Mapping Program
of the USGS.
The digital geologic map database for the Cucamonga Peak 7.5' quadrangle has been
created as a general-purpose data set that is applicable to other land-related
investigations in the earth and biological sciences. For example, the U.S. Forest
Service and the San Bernardino National Forest may use the map and data base as a basic
geologic data source for soil studies, mineral resource evaluations, road building,
biological surveys, and general forest management. The Cucamonga Peak database is not
suitable for site-specific geologic evaluations at scales greater than 1:24,000 (1in =
2,000 ft.).
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 19740401
Ending_Date: 19810801
Currentness_Reference: New data and previously published data
Status:
Progress: Complete
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -117.62509226
East_Bounding_Coordinate: -117.49990774
North_Bounding_Coordinate: 34.24999995
South_Bounding_Coordinate: 34.1249841
Keywords:
Theme:
Theme_Keyword_Thesaurus: USGS Thesaurus
Theme_Keyword: geology
Theme_Keyword: geologic maps
Theme_Keyword: bedrock geologic units
Theme_Keyword: surficial geologic units
Theme_Keyword: geologic structure
Theme_Keyword: geospatial datasets
Theme:
Theme_Keyword_Thesaurus: none
Theme_Keyword: San Jacinto Fault
Theme_Keyword: Cucamonga Fault
Theme_Keyword: San Gabriel Mountains
Theme_Keyword: Pelona Schist
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Categories
Theme_Keyword: geoscientificInformation
Place:
Place_Keyword_Thesaurus: none
Place_Keyword: California
Place_Keyword: San Bernardino County
Place_Keyword: Cucamonga Peak 7.5' quadrangle
Place:
Place_Keyword_Thesaurus: Augmented FIPS 10-4 and FIPS 6-4
Place_Keyword: f06071 = San Bernardino
Access_Constraints: None
Use_Constraints:
The Cucamonga Peak 7.5' geologic-map database should be used to evaluate and understand
the geologic character of the Cucamonga Peak 7.5' quadrangle as a whole. The data
should not be used for purposes of site-specific land-use planning or site-specific
geologic evaluations. The database is sufficiently detailed to identify and
characterize geologic materials and structures. However, it is not sufficiently
detailed for site-specific determinations.
Use of this digital geologic map database 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 compiled and edited at a scale of
1:24,000 means that higher resolution information may not have been uniformly retained
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, although higher resolution data is incorporated in parts
of the map, the resolution of the combined output will be limited by the lower
resolution data.
Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Douglas M. Morton
Contact_Organization:
U.S. Geological Survey, Western Region, Earth Surface Processes Team
Contact_Position: Project geologist
Contact_Address:
Address_Type: mailing address
Address:
U.S. Geological Survey
Department of Earth Science
University of California, Riverside
City: Riverside
State_or_Province: California
Postal_Code: 92521
Country: United States of America
Contact_Voice_Telephone: (909) 276-6397
Contact_Facsimile_Telephone: (909) 276-6295
Contact_Electronic_Mail_Address: scamp@usgs.gov
Browse_Graphic:
Browse_Graphic_File_Name: http://pubs.usgs.gov/of/2001/0311/images/cuc_map.jpg
Browse_Graphic_File_Description:
Non-navigable .jpg image of the geologic map, topographic base, Correlation of Map
Units, Description of Map Units and key to point and line symbols.
400x406 pixels, 32-bit RGB true color, 45k bytes.
Browse_Graphic_File_Type: JPEG
Browse_Graphic:
Browse_Graphic_File_Name: http://pubs.usgs.gov/of/2001/0311/pdf/cuc_map.pdf
Browse_Graphic_File_Description:
Navigable portable document file (.pdf) image of the geologic map, topographic base,
Correlation of Map Units, Description of Map Units and key to point and line symbols.
3.3 megabytes.
Browse_Graphic_File_Type: PDF
Data_Set_Credit:
Technical review by Michael Kennedy led to significant improvements that eventually were
reflected in aspects of the database, the plot file, and in the description of the
geologic units of the Cucamonga Peak 7.5' quadrangle.
Geologic mapping and digital preparation of this report were sponsored jointly by (1)
the National Cooperative Geologic Mapping Program of the U.S. Geological Survey, (2)
the California Division of Mines and Geology, and (3) the Southern California Areal
Mapping Project (SCAMP). In our digital preparation of the data set, carried out in
the SCAMP Geographic Information System laboratory at the University of California,
Riverside by Catherine Koukladas, and in the USGS Geographic Information System
laboratory of the Mineral Resources Program of the U.S. Geological Survey in Spokane,
Washington by Pamela M. Cossette, we received valuable assistance from Rachel Alvarez
in Riverside, California, and from Paul C. Hyndman in Spokane, Washington.
Native_Data_Set_Environment:
SunOS, 5.7, sun4u UNIX
ARC/INFO version 7.2.1
Cross_Reference:
Citation_Information:
Originator: D.M. Morton
Publication_Date: 1976
Title:
Geologic map of the Cucamonga fault zone between San Antonio Canyon and Cajon Creek,
southern California
Edition: Version 1.0
Geospatial_Data_Presentation_Form: paper map
Series_Information:
Series_Name: U.S. Geological Survey Open-File Report
Issue_Identification: 76-726
Publication_Information:
Publication_Place: Menlo Park, California
Publisher: U.S. Geological Survey