State of Washington ALBERT D. ROSELLINI, Governor Department of Conservation EARL COE, Director DIVISION OF MINES AND GEOLOGY MARSHALL T. HUNTTING, Supervisor Bulletin No. 50 Geology and Mineral Deposits of the North Half of the VAN ZANDT QUADRANGLE, Whatcom County, Washington By WAYNE S. MOEN STATE PRINTING PLANT, OLYMPI A . WASH. 1962 For sale b y Department of Conservation, Olympia, Washington. Price, $1.50. COLUMBIA SUMAS VALLEY NOOKSACK VALLEY RIVER BLACK MTN MTN_ MTN SUMAS PARA D I SE VALLEY PANORAMA OF MAP AREA Looking east from the north end of Sumas Mountain. Above the photo is sketch of the main physiographlc features of the area. CONTENTS Page Abstract 1 Introduction . 1 Scope or the report . 1 Field work and acknowledgments . 2 Previous investigations . 2 History and mineral production . 3 Location and access . 4 Land ownership . 5 Topography . 5 Sumas Mountain . 6 Black Mountain . 6 Red Mountain . 6 Vedder Mountain . 6 Slide Mountain . • . 7 General geology . 7 Rock units . 8 Sedimentary rocks . 8 Chilliwack Group . • . 8 Distribution . 10 Argillaceous rocks . 10 Chert . 11 Siltstone, graywacke, and conglomerate . 12 Limestone . 15 Lower Mesozoic (?) rocks . 18 Upper Cretaceous-lower Tertiary rocks . 21 Chuckanut Formation . 21 Tertiary continental rocks . 26 Quaternary sediments ................. ... ..... .. ..... , . 31 Pleistocene deposits . 31 Recent deposits . 32 Igneous rocks . 34 Chilliwack Group volcanic rocks . 34 Sumas Mountain Serpentinite . 42 Crystalline complex . 49 Structure . 57 Vedder Mountain . 58 Sumas Mountain . 58 Slide Mountain . 60 Red Mountain and Black Mountain . 60 Geologic history . 62 Paleozoic era . 62 Mesozoic era . 63 Cenozoic era . 63 Glaciation . 64 Glacial topography . 66 iii CONTENTS Page Mineral deposits . • . • . 67 Clay . • . • . 67 Fire clay . 67 General discussion . • . 67 Area No. l . 70 Area No. 2 . • . • . • . 77 Area No. 3 . • . 80 Area No. 4 . • . • . • . 84 Glacial clay ............ ..... • ..... , . 85 Conclusions . • . 86 Limestone . 86 Silver Lake quarry . 87 Kendall quarry . • . 89 Boulder Creek quarry . 91 Doaks Creek quarry . • . 93 Balfour quarry . 94 Other limestone deposits . • . 96 Analyses . 98 Silica .......................... .. ..... ....... ... .... , .. • .. 101 Olympic Portland Cement Company silica deposit ... ... ...... 101 Iron .. ......... .. ........ ........... .. ............... .... 104 Sumas Mountain iron deposit .. ............ ... .. .. .. ... 104 Chromite ..... ..... .............. .............. • .... .... 112 General statement .... ............ ....... • ... .. ...... ... 112 Sumas Mountain .............. ..... • .. ... ...... ...... .. 112 Breckenridge Creek deposit . • . 114 Coal ................... ...... ........... • .. .. • .. .. .... 118 Quarry stone . ...... .. ...... .. ............ .. ... ..... 119 Sand and gravel . • . 119 Gold .......... .. ........... .......... .. ....... ........ 120 Old Nooksack mine . .. .• . ... ... • ..... ................. 120 Placer gold deposits .. ............. ..... .. .... ..... 122 Copper . .... .. .. ..... .. .. .................. ... .. .... 123 Boulder Creek deposit . • . • . 123 Miscellaneous occurrences . 125 Summary . • . 125 References cited . • . 127 iv ILLUSTRATIONS Panorama of map area Frontispiece PLATE 1. Geologic map of north half of the Van Zandt quadrangle, Whatcom County, Washington . .. ................ .... In pocket 2. Land ownership map of the north half of the Van Zandt quadrangle . .................. ..