| Title | Basalt (and other igneous) rip-rap in Duluth along Lake Superior |
| Description | Basalt rip-rap in Duluth along Lake Superior, St. Louis, Minnesota. |
| Chronostratigraphy | Late Proterozoic, Keweenawan |
| Lithostratigraphy | North Shore Volcanic Group |
| Geologic province | Midcontinent Rift |
| Location | USA ▹ Minnesota ▹ St. Louis. Near Duluth. Duluth Quadrangle. |
| Photographer | Joseph Hartman. 2002-02-21. |
| Collection | Joseph Hartman C08828. |
| Key words | rip-rap |
| Tech details | 414 KB. Outcrop. Kodachrome, TIFF. |
| GeoDIL number | 2407 |
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