GEOLOGY OF THE UPPER PROTEROZOIC TO LOWER CAMBRIAN THREE SISTERS FORMATION, GYPSY QUARTZITE, AND ADDY QUARTZITE, STEVENS AND PEND OREILLE COUNTIES, NORTHEASTERN WASHING TON by KEVIN A. LINDSEY, DAVID R. GAYLORD, and LOUIS H. GROFFMAN WASHINGTON DIVISION OF GEOLOGY AND EARTH RESOURCES REPORT OF INVESTIGATIONS 30 1990 WASHINGTON STATE DEPARTMENT OF Natural Resources Bdan Boyle • Commlss!oner ol Publlc Lands Ar1 Stearns • Supervisor Division of Geology and Earth Resources Raymond Lasmanfs. State Geologist GEOLOGY OF THE UPPER PROTEROZOIC TO LOWER CAMBRIAN THREE SISTERS FORMATION, GYPSY QUARTZITE, AND ADDY QUARTZITE STEVENS AND PEND OREILLE COUNTIES, NORTHEASTERN WASHING TON by KEVIN A. LINDSEY, DAVID R. GAYLORD, AND LOUIS H. GROFFMAN WASHINGTON DIVISION OF GEOLOGY AND EARTH RESOURCES REPORT OF INVESTIGATIONS 30 1990 ''~~ NaturalWASHING'!ON STATE Resources DEPARTMENT OF Bnon Boyle - Commissioner of Public Lands Art Stearns • Su_pervlsor Division o! Geology and Earth Resources Raymond Lasmants. Slate Geologisl This report is available from: Publications Washington Department of Natural Resources Division of Geology and Earth Resources Mail Stop PY-12 Olympia. WA 98504 Price $1.38 Tax .12 (WA residents only) Total $1.50 Mail orders must be prepaid; please add $1.00 to each order for postage and handling. Make checks payable to the Department of Natural Resources. This book is printed on acid-free paper. Printed in the United Stat.es of America. ii CONTENTS Abstract.............................................................................................................................................................................. 1 Introduction ........................................................................................................................................... ............ ................. 1 Location of study areas............................................................................................................................................... 1 Objectives of this report............................................... ............................................................................................... 2 Regional geologic setting................................................................................................................................................... 2 Stratigraphy................................................................................................................................................................. 2 Structural geology....................................................................................................................................................... 3 Stratigraphy of the Addy Quartzite, Three Sisters Fonnation, and Gypsy Quartzite ........................... ............................ 6 History ..................................................................................................................................................... -.................. 6 Addy Quartzite................................................................................... .................................................................... 6 Gypsy Quartzite and Three Sisters Fonnation....................................................................................................... 7 Stratigraphy................................................................................................................... .............................................. 9 Three Sisters Fonnation ............... ........................................ ................................ ............ ...................................... 9 Gypsy Quartzite ..................................................................................................................................................... 12 Addy Quartzite ....................................................................................................................................................... 15 Age .............................................................................................................................................................................. 20 Three Sisters Fonnation and Gypsy Quartzite....................................................................................................... 20 Addy Quartzite ....................................................................................................................................................... 21 Correlation................................................................................................................................................................... 21 Stratigraphic summary and proposed type localities and sections.................................................................................... 23 Introduction................................................................................................................................................................. 23 Type sections............................................................................... ................................................................................ 25 Gypsy Quartzite ... ..... ... .... .... .... ........ ........ .... .. ... .. .. .... .... .. .... ... ... .. ......... ...... ....... .... .... ............ .... .... ........ ..... ... 25 Addy Quartzite....................................................................................................................................................... 25 Geologic history .. ..... .... .... .... ... ..... ........ ........ .... .... .... ... ..... .. .. ... ..... .. .. .... ..... ... .... .... ............ .... ........ ....... ...... ........ ....... ..... ..... 25 Introduction................................................................................................................................................................. 25 Three Sisters Fonnation: Rift deposition.................................................................................................................... 29 Addy and Gypsy Quartzites: Passive margin sedimentation ............... ...................................................................... 30 Economic geology ........................................................................................... ................................................................... 33 Silica mines................................................................................................................................................................. 33 Lane Mountain quarry................................... ........................................................................................................ 33 Inactive silica operations....................................................................................................................................... 34 Other friable quartzite localities ........................................................................... .................... ............................. ..... 34 Summary ............................................................................................................................................................................. 34 Acknowledgments.............................................................................................................................................................. 35 References cited ............... ........ ............................................................................................ ............ .................................. 35 ILLUSTRATIONS Figure 1. Map showing location of the study areas in northeastern Washington............................................................. 2 Figure 2. Map showing outcrops of the Three Sisters Fonnation and Gypsy Quartzite, northern Pend Oreille County, Washington ........................................................................................................ 3 Figure 3. Map showing outcrops of the Addy Quartzite, central and southern Stevens County, Washington............................................................................................................................................ 4 Figure 4. lsopach map of the Cordilleran miogeocline ................................................................................ ..................... 5 iii Figure 5. Map showing location of the Kootenay arc........................................................................................................ 5 Figure 6. Map showing locations of selected previous studies in the Addy Quartzite and Gypsy Quartzite, northeastern Washington......................................................................................................... 7 Figure 7. Diagram showing Late Proterozoic to Cambrian stratigraphy in northeastern Washington.......................................................................................................................................................... 8 Figure 8. Idealized stratigraphic column of the Late Proterozoic Three Sisters Fonnation ....... ................. ..................... 10 Figure 9. Photograph of cross-bedded quartzite and pebble conglomerate of the lower quartzite unit of the Three Sisters Fonnation 3 km south of Gypsy Peak............................................... 11 Figure 10. Photograph of massive cobble and boulder conglomerate of the conglomerate unit of the Three Sisters Formation 2 km north of Sullivan