Online Links:
| Range of values | |
|---|---|
| Minimum: | 115.0 |
| Maximum: | 400.0 |
| Units: | feet |
| Resolution: | 1 |
| Range of values | |
|---|---|
| Minimum: | 0.705 |
| Maximum: | 2304825.9 |
| Units: | meters |
| Value | Definition |
|---|---|
| Allen | John Eliot Allen (1986) |
| Allison (fig) | 249 erratic locations were digitized from a map figure in I.S. Allison (1935), in which he indicates the Public Land Office Survey sections (2.6 sq. km; 1 sq. mi) that contain erratics . Consequently, the locations and elevations of these 249 glacial erratics are less well known than others in the database, may include duplicates of erratics described in other sources, and are symbolized by gray triangles on our maps. |
| Allison(fig) | 249 erratic locations were digitized from a map figure in I.S. Allison (1935), in which he indicates the Public Land Office Survey sections (2.6 sq. km; 1 sq. mi) that contain erratics . Consequently, the locations and elevations of these 249 glacial erratics are less well known than others in the database, may include duplicates of erratics described in other sources, and are symbolized by gray triangles on our maps. |
| Allison(table) | I.S. Allison (1935) published a comprehensive study of Willamette Valley glacial erratics. Allison's original records are not available, but 42 locations of glacial erratics were located to the quarter- or half-section in his 1935 publication [ Source field of erratics feature class = Allison(table) E.T. 8/8/03]. These 42 locations were digitized using the elevation and Public Land Survey information published by Allison (1935). |
| Beeson | |
| Bela | Field sheets and notes from mapping completed by Jim Bela (Bela, 1981) in the late 70's and early 80's in the west-central Willamette Valley provided the locations of 16 erratics. |
| Bretz, G. H. | |
| Fillmore | |
| Hodge | |
| Hughes | |
| McDowell | |
| O'Connor | |
| Piper | Arthur M. Piper cataloged field observations (mostly during 1928 and 1929) and literature citations of glacial erratics in the Willamette Valley and Portland basin in a series of 82 index cards and accompanying field maps archived at the U.S. Geological Survey Water Resources office in Portland, Oregon. From these records, 54 erratic locations were documented. |
| Treasher | |
| Wells | Ray Wells |
| Wozniak |
| Range of values | |
|---|---|
| Minimum: | 32 |
| Maximum: | 827 |
| Units: | feet |
| Resolution: | 1 |
| Value | Definition |
|---|---|
| andesite | |
| andesite or granodiorite | |
| argillite | |
| basic ig. rocks | basic igneous rock |
| biotite granite | |
| biotite granodiorite | |
| biotite hornblende granodiorite | |
| biotite schist (?) | |
| biotite schist, biotite grano gneiss | grano probably refers to granodiorite |
| biotite, hornblende, granodiorite | |
| diorite | |
| felsic? diabase? metavolcanic | |
| gneiss | |
| gneiss, qtzite | qtzite = quartzite |
| granite | |
| granite and basalt | |
| granite gneiss | |
| granite or granodiorite | |
| granite, basalt, granodiorite | |
| granite, gabbro | |
| granite, gneiss | |
| granite, quartzite, porphyry | |
| granite-gneiss with hornblende inclusions | |
| granite/granodiorite/porph. rhyolite/quartzite | |
| granitic | |
| granitic and sandstone | |
| granitic, sandstone | |
| granitic? | |
| granodiorite | |
| granodiorite or granite | |
| granodiorite w/ feldspar phenos | phenos are phenocrysts, visible crystals |
| granodiorite, bs, diabse | bs probably refers to basalt; diabse is probably diabase |
| iron-nickel meteorite | |
| kyanite | |
| Limestone, somewhat fluted, pitted by solution | |
| metamorphic (phyllite?) | |
| metasedimentary, metavolcanic | |
| mostly granite | |
| porph. biotite granodiorite schist | |
| pyritic quartzite | |
| qtz (?) | quartz |
| qtz schist | qtz = quartz |
| qtz. diorite | qtz = quartz |
| quartzite | |
| quartzite, granite/gneiss | |
| quartzite, granitic | |
| quartzitic and quartz | |
| quartzose biotite hornblende(?) granodiorite | |
| quartzose ig. or met. sed. | quartz-bearing igneous or metasediment? |
| several kinds | |
| several kinds of rocks | |
| slate | |
| unknown | |
| varied | |
| xtal gabbro(?) | xtal = crystalline? |
| Value | Definition |
|---|---|
| fair | |
| good |
| Value | Definition |
|---|---|
| Qfc | Coarse Missoula Flood deposits |
| Qff1 | Younger and lower fine-grained Missoula Flood deposits |
| Qff2 | Main body of fine-grained Missoula Flood deposits |
| Qa | Alluvium and glacial-outburst flood sediment (Pleistocene) |
| Qlg | Lacustrine deposit, gravelly phase |
| Value | Definition |
|---|---|
| coarse | coarse-grained deposit |
| fine | fine-grained deposit |
| Range of values | |
|---|---|
| Minimum: | 0 |
| Maximum: | 13193 |
This database represents the most comprehensive compilation of Willamette Valley and Portland basin glacial erratic data to date. 400 records are contained herein, representing work from the 1920's to the present.
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 1:250,000 means that higher resolution information is not present in the dataset. Plotting at scales larger than 1:250,000 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.
This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
| Data format: | Topographic contours, erratic locations, and geologic units in format Shapefile (version 1.0) Size: 304 |
|---|---|
| Network links: |
http://pubs.usgs.gov/of/2003/of03-408/OF03_408_SHP.zip |
| Data format: | Digital elevation models, shaded relief, and hydrography in format ArcInfo Grid (version 8.x) Size: 304 |
|---|---|
| Network links: |
http://pubs.usgs.gov/of/2003/of03-408/OF03_408_SHP.zip |