Late PleistoceneStratigraphy in theSouth-Central Puget Lowland,Pierce County, Washingtonby Richard K. Bordenand Kathy Goetz TroostWASHINGTONDIVISION OF GEOLOGYAND EARTH RESOURCESReport of Investigations 33December 2001NATURAL RESOURCESLocation ofstudy areaLate PleistoceneStratigraphy in theSouth-Central Puget Lowland,Pierce County, Washingtonby Richard K. Bordenand Kathy Goetz TroostWASHINGTONDIVISION OF GEOLOGYAND EARTH RESOURCESReport of Investigations 33December 2001iiDISCLAIMERNeither the State of Washington, nor any agency thereof, nor any of their em-ployees, makes any warranty, express or implied, or assumes any legal liabilityor responsibility for the accuracy, completeness, or usefulness of any informa-tion, apparatus, product, or process disclosed, or represents that its use would notinfringe privately owned rights. Reference herein to any specific commercialproduct, process, or service by trade name, trademark, manufacturer, or other-wise, does not necessarily constitute or imply its endorsement, recommendation,or favoring by the State of Washington or any agency thereof. The views andopinions of authors expressed herein do not necessarily state or reflect those ofthe State of Washington or any agency thereof.WASHINGTON DEPARTMENT OF NATURAL RESOURCESDoug Sutherland—Commissioner of Public LandsDIVISION OF GEOLOGY AND EARTH RESOURCESRon Teissere—State GeologistDavid K. Norman—Assistant State GeologistThis report is available from:PublicationsWashington Division of Geology and Earth ResourcesPO Box 47007Olympia, WA 98504-7007Phone: (360) 902-1450Fax: (360) 902-1785E-mail: [email protected]: http://www.wa.gov/dnr/htdocs/ger/Front Cover: Former Woodworth quarry on Hylebos Waterway, Tacoma.Photo by K. Troost, 1995.Back Cover: Abandoned quarry on Hylebos Waterway, Tacoma. Photo byK. Troost, 1999.Printed on recycled paper.Printed in the United States of AmericaContentsAbstract ...............................................1Introduction.............................................1Stratigraphic nomenclature ...................................1Recent investigations in the study area ............................4Field and laboratory procedures .................................4Glacial and nonglacial deposition in the Puget Lowland ....................5Nonglacial deposits .......................................5Glacial deposits .........................................6Differentiating glacial and nonglacial sediments .......................7Results ...............................................8Hylebos Waterway measured sections .............................8Route 7 measured section....................................9Tacoma boathouse measured section .............................10Sunset Beach measured section ................................11Solo Point measured section .................................11Subsurface data.........................................11Discussion .............................................12Vashon Drift ..........................................12Olympia beds..........................................17Pre-Olympia drift .......................................17Second nonglacial deposits ..................................17Third glacial drift .......................................19Third nonglacial deposits ...................................19Hydrogeologic implications ..................................20Conclusions ............................................21Acknowledgments ........................................21References cited .........................................21APPENDICESAppendix A. Borehole summary ................................24Appendix B. Boreholes with radiocarbon data ........................27FIGURESFigure 1. Puget Lowland and study area ............................2Figure 2. Borehole and cross section location map ......................4Figure 3. Locations of radiocarbon samples ..........................5Figure 4. Modern Puget Lowland depositional environments ................6Figure 5. Location map of Puget Lowland river sediment samples .............6Figure 6. Woodworth quarry composite measured section ..................9Figure 7. Manke quarry measured section ...........................9Figure 8. Foran quarry measured section ...........................10Figure 9. Route 7 measured section..............................10Figure 10. Tacoma boathouse measured section .......................10Figure 11. Sunset Beach measured section ..........................11Figure 12. Solo Point measured section ............................11Figure 13. Cross section A–A¢ .................................12Figure 14. Cross section B–B¢ .................................13Figure 15. Cross section C–C¢ .................................13Figure 16. Cross section D–D¢ .................................14Figure 17. Cross section E–E¢ .................................14iiiFigure 18. Paleotopographic map of the base of the Vashon Drift..............15Figure 19. Paleotopographic map of the top of the pre-Olympia drift............16Figure 20. Isopach map of the pre-Olympia drift .......................16Figure 21. Paleotopographic map of the top of the second nonglacial deposits ......18Figure 22. Isopach map of the second nonglacial deposits ..................18Figure 23. Paleotopographic map of the top of the third glacial drift ............19Figure 24. Paleotopographic map of the top of the third nonglacial deposits ........20Figure 25. Generalized stratigraphic and hydrostratigraphic column forwest-central Pierce County .............................20Figure B-1. Borehole DA-2c,d .................................28Figure B-2. Borehole DA-12e .................................29Figure B-3. Borehole 4/6 Composite ..............................30Figure B-4. Borehole LF4-MW12B ..............................31TABLESTable 1. Puget Lowland stratigraphic nomenclature ......................3Table 2. Sediment characteristics of selected Puget Lowland rivers .............7Table 3. Summary of radiocarbon data .............................8ivLate Pleistocene Stratigraphy in the South-CentralPuget Lowland, Pierce County, WashingtonRichard K. BordenKennecott Utah Copper Corporation8315 West 3595 SouthPO Box 6001; Magna, UT 84044Kathy Goetz TroostUniversity of WashingtonDepartment of Earth and Space SciencesBox 351310; Seattle, WA 98195ABSTRACTTwo distinct sets of late Pleistocene stratigraphic nomenclatures have been developed for