Aerial view, the Three Sisters volcanoes in Oregon, from the south looking north. Left to right -- South Sister, Middle Sister, and North Sister. USGS Photograph taken in September 1985 by Lyn Topinka
This map presents the stratigraphic and structural setting of volcanic and sedimentary strata deposited during the past 35 million years across 4,430 km2 in central Oregon. Snowfall in the Cascade Range (west part of map area) recharges important aquifers in the Deschutes basin (central part of map). The area includes the majestic peaks of the Three Sisters volcanoes, where continued eruptions of basalt and rhyolite in the past 3,000 years indicate an ongoing volcanic hazard. The Sisters fault zone, with several potentially active faults, traverses the map from southeast to northwest. |
File
Name |
File
Type and Description |
File
Size |
| ||
FILES for VIEWING and PLOTTING (Both tagged and untagged versions follow.) |
||
PDF file of the 49-page descriptive geologic pamphlet that accompanies the map | 448 KB |
|
for accessibility using assistive technology such as screen readers | 664 KB |
|
Geologic map and description of map units (PDF file of 52" x 42" map sheet that can be used for viewing map in a browser, as well as for plotting) | 23.2 MB |
|
Correlation of map units and cross sections (PDF file of 39" x 33" sheet) | 1.8 MB |
Also of Interest
Koch, Richard D., Ramsey, David W., Sherrod, David R., Taylor, Edward M., Ferns, Mark L., Scott, William E., Conrey, Richard M., and Smith, Gary A., 2010, Database for the geologic map of the Bend 30- x 60-minute quadrangle, central Oregon: U.S. Geological Survey Data Series 303 [https://pubs.usgs.gov/ds/303/].
For questions about the content of this report, contact Dave Sherrod
Download a current version of Acrobat Reader for free
| Help
| PDF help
| Publications main page | Western reports main page |
| Western Geologic and Miscellaneous Investigation Series Maps |
| Privacy
Statement | Disclaimer
| Accessibility |
| Geologic
Division | Volcano Hazards Program
|
This map is also available from:
USGS Information Services, Box 25286
Federal Center, Denver, CO 80225
telephone: 1-888-ASK-USGS; e-mail: infoservices@usgs.gov