Montana Bureau of Mines and Geology Ground-Water Assessment Atlas No. 2, Part B, Map 6 A Department of Montana Tech of The University of Montana December 2004 114o R19W 48o30 R20W R21W Qal Qal T32N R22W Qgta Ybe Qgt 114o 37 30 R23W Qao Qgo R24W Qgt Qao o Ybe Qgt 48 30 Qgo Qgt Ybe Qgo Qgt T32N Ybe Tk Qgt Qgt Qls Ybe Qaf Qgo Qao Qaf Qgta Ybe Qgo Qgt Ybe Key to Symbols Qal Ybe Qal Qao Qal Qgt Qaf Qgt Contact, dashed where approximate Qgo Ybe Qgt Ybe Qls Qgo Qlk Ybe Qls Stream 71 Ybe Qgt 82 Qgt W Qls Qgoo h Qls Road Ybe Tk 70 it Qgo Qaf e Qgta Qgo 81 Township boundary, section boundary Ybe f Qgta Qgo i 21a s 83 28 Tk h Tk 21 T31N Population center Qgl L 23 22 Qls Qgt 69 a 27 Marsh Ybe Qgt Ybe k Qgta 24 e Qgo 26 25 Qgo Qgt Qgt Qgoo Lake or reservoir Ybe Qls Qlk 84 Qgo T31N Qal Qgt Tk Qgt Qgt 5 Location where geologic notes were recorded, photographs taken, and/or a vertical Qlk Qal Qaf section was described. Qgt Ybe Qal Qgo Qlk Ybe Qgt Qgt Ybe Ybe Qgo GLACIOFLUVIAL CHANNEL - Channelized depressions recognized from aerial Qgo Qgo Qgt Qal photographs and topographic expression; associated with deposits of glacial outwash Ybe in some areas; multiple types of channels are represented: ice-marginal channels: Ybe Qgt Qgt Qgi Qaf Qgo Qgta Qgo Qgo Qgi irregular linear erosional channels formed by channelized flow next to, or partially Qgo Ybe 73 Qgo Qgl Tk beneath the lateral margins of glaciers; commonly form notches, meander loops, and Qlk 74 Qgt Qgt Ybe Qgt Qgo some integrated drainage networks in bedrock or till that then may have become modern streams; some contain series of internally drained depressions (pools formed Qgt 66 Qgo Qgl Qgt Qgi Qal Qaf Qgo by scour). Abandoned alluvial channels: channel traces in unconsolidated deposits Qal T Qaf Qe Qe Qgo that show the positions of abandoned distributary channels across outwash. Paleoflood a Qgo Qgi l Ybe Qgo Whitefish Qgt channels: channels formed predominantly in bedrock or till formed by catastrophic l Qgt Qgo 75 Ybe y Qgl 78 Qao 32 80 releases of water. Qgt 68 Qal 72 QTs Qgl Qgta Qgo Qal Qgt L 76 Qgo Qgt 33 Qgo Ybe a Qgo Qgi Ybe Qgta Qao 34 Qgi Qgls Qgoo CREST OF DEPOSITIONAL LANDFORM - Ridgetops of landforms formed on k Qgi Qgi Ybe Pleistocene or Holocene sediment; multiple types of landforms are represented: e Qlk QglQgo Ybe Drumlins and moraines: mostly oriented parallel to glacier-flow directions, in till Qgt Qgl Qgo Qgo Hungry Horse deposits; Kames: conical and elongate ridges, in ice-contact deposits; Disintegration Qgl Qgt Qgo Qgi Columbia Falls Qgl ridges: elongate, sinuous and intersecting ridges, in ablation till (Gravenor and Qaf Qgt Qao Qgo Qgt Qal Qgl Qgl Kupsch, 1959; Flint, 1971; Goldthwait, 1975); Eolian dunes: crests of stabilized Ybe Ybe Qgl Qgo dunes, in eolian sand; Debris-flow levees: ridges formed parallel to margins of debris Qaf Qgt Qgo Qaf Qgo Qgt Qao flows, rare in ablation till and ice-contact deposits in areas of high relief. Qge Ybe Qgt Qe Qgt Qlk 77 79 35 Ybe Qaf Qaf Qgt 31 SCALE 1:70,000 Qgta Qgl Qlk Qgo Qao Qaf Universal Transverse Mercator Projection Qgt Qgo Qgl T30N 67 Qao Zone 11 Qgt Qgo 30 Datum NAD27 Qgo S Ybe t Qgta 29 Qgta il Qgo Qao Ybe Qgo l Ybe 39 40 41 w Qgta 45 Qgt Qgt Qaf Hungry T30N a 46 Qgi 44 Qgo Qgo t Qao Qao Horse Qgt e 19 43 Qgl 36 20 42 Reservoir r 18a Qgt Qgo Ybe Qe Qe 18 Qls Correlation of Units Qgt R i Alluvium Eolian Alluvial Fan Landslide Lacustrine Till and Ice Contact v Qgt and Outwash Deposits Deposits Deposits Deposits Deposits Qgo e Qgo Qgta Qgl r Qaf Qgt Qgl Qgo Qal Ybe Qe Qaf Qls Qlk Qgl Qao Qaf Holocene Qgo Qgta Qao Qgo Qgls Qgo Qao Qgi Qgl Qgt Qgt Qgta Qgo Qgi Qgi Qge Qgt Qgo Qao 85 Qgta Qgt Qgta Qe Qao Qgt 86 Qgl Pleistocene Qgi 86a Ybe L Qao Qgo Qgt Qao Qgoo o Qe 86b Qgo st 86c Qaf QTs ? QgoC Qge 87 88 unconformity r Qgt Qgt Kishenehn Formation eek Ybe Qgt Eocene - Ybe Qgt Qgl 17 Qal Qe Qgo Qgt 15 Qgo Tk Miocene Qaf Qgt Qgo Qgt Qe unconformity Ybe Qge Qgl 16 Qgt Qgt Qgi Belt Supergroup Middle Qe Qgt Qgt r Ybe Proterozoic Qe e Qgo Qgt Qaf Qe v T29N i Qgi Qgt Qgo Qgo 13 14 T29N R Qgl Qgt Ybe Qe Qe 12 Qgta Qgi h Qe Qaf Qgo Qe Qgt Qe s Qgi Qgt i Qal Qe f Qe Qe Qgi Qgo Qgt Qgi Qgl e Qgi Qgt t Qgl i Qgta h Qlk Qgo Qgi Qgt Qgi Ybe W r Lake Blaine Qgt Qe e Qgl Qgt Qal v Qgl Qgi Qgi i Qgt Qgt R Qaf Qao Qgi Qgo Qgt Qao 65 Qao Qaf R23W Qal Qe Qgt R24W Qgl d Qgi Qgt Qgo Qgt Qgt a Qao Qgt e 10 Qgi h Ybe Qgta Qgi t Qgl Ybe Qgta a Qaf Qao l Qgt F Qgi Qgo Qgi Qgo 11 Qe Qgi Ybe Ybe Qgt Qgls Qal Qgta Qgi Qgl Qgl Qaf Qgt Qgta Ybe Ybe Qgi 90 Qgt QgoQgls Qgi Qgi Qgo Qgls 8 Qgi Qgo Qgl Qgls Qgta Qgo Qgl 8a Qao Qaf Ybe Qao Qgi 7 Ybe Qao Qgl Ybe 9 Qgi Qgo Qgi Qgt Kalispell Qgls Ybe 89 Qgt Qgl Qgi Qaf Qe Qgo T28N Qgo Qgi Qge Qgt Qgo Qgo Ybe Qgi Qgo Qgi Qgi Qgo Qgi Qgl T28N Ybe Qge Qgi Qgi Qgo 6 Qgt Qgi Qgo Qgo Qgo Qgta Qal Ybe Foy Lake Ybe Qgi Qge Qge Qgta Qao Qgi Qgt Ybe Ybe Qgta Ybe Qao Qgo Ybe Qao Qgo Qgta Ybe Qgo Qgo Qgo Qal Qgo Ybe Qal Ybe Ybe 5 Qgt Ybe Qal Echo Lake Qlk Ybe T27N Qgta Qal Ybe Qgo Qgi Ybe Qgta Ybe Ybe o Qgo Qgo 48 0730 R22W R23W Qgi 114o30 Qal Description of Map Units Qgt Qlk Qgo Qal ALLUVIUM OF MODERN CHANNELS AND FLOODPLAINS (Holocene) - Light to medium brown and grayish brown sand and silt, Ybe Qgt Qao and lesser amounts of pebbles, cobbles, and clay along active stream valleys and areas of sheetwash; contains minor amount of colluvium Qgt Qe Qgls T27N Qao 2 4 along the bases of steep slopes; thicknesses average 30 feet, but reach 90 feet in paleochannels south and southeast of Kalispell; ground 61 Qge Qgi Qge water commonly near land surface; produces significant quantities of water. Ybe Qgi 3 1 Ybe Ybe Ybe Qao Qaf ALLUVIAL FAN DEPOSIT (Holocene) - Grayish brown and light to dark yellowish brown sand, silt, pebbles, cobbles, and boulders Ybe Qgt deposited in fan-shaped landforms downslope from canyon mouths; thicknesses range from 1 to 60 feet; ground water commonly near T27N Qlk Ybe Ybe Qgo land surface; locally produces water. Qaf Qgt Qgl Qao Ybe Qe EOLIAN DEPOSIT (Holocene) - Dark to light yellowish brown fine and very fine-grained well sorted sand deposited as eolian dunes and Ybe Ybe Ybe sand sheets; grains mostly of quartz with common argillic or calcareous rock fragments; pebble-sized clasts of argillite, quartzite, and 62 weakly consolidated siltstone occur as rare particles in deposits and locally as layers on or near the ground surface; a distinctive bed of 60 Qgi white to very pale orange volcanic ash (Glacier Peak ash, dated at 11,200 14C yr; Carrara, 1995) occurs within or near the base; bedding Qgi Qgt Qgt Qgl is massive where the unit is thin, but wind-ripple cross-laminations and large-scale sandflow cross stratification are common in thicker Qal Ybe Ybe deposits; the deposit is truncated near stream courses by alluvium; soils occur at the surface and buried within the deposit; dune forms Qlk are poorly preserved due to modification during stabilization and post-depositional erosion; thickness ranges from 1 to 40 feet; water table Qgls is typically below the unit, but the unit may be saturated seasonally; not known to produce significant quantities of water. Bigfork Qao Qao Qlk LAKE DEPOSIT (Holocene) - Mostly calcareous silt, clay, and organic debris deposited in perennial and ephemeral lakes; includes minor amounts of sand and gravel; distribution of unit inferred beneath lakes and marshes; thickness unknown, but likely 1-30 feet; ground water Ybe Qgo Ybe Ybe S commonly near land surface; not known to produce water. Ybe Qgl w a Qgta Qls LANDSLIDE DEPOSIT (Holocene and upper Pleistocene) - Boulders, cobbles, and pebbles in a light to dark brown matrix of sand and QTs Qls n Ybe Qgo silt; clasts are mostly angular and subangular; deposited by gravity sliding to an area near the base of a hill or mountain slope; surface of 59 Qgt R unit is typically hummocky and lobate in form; thickness ranges from 1 to 80 feet; ground water commonly near land surface; locally Ybe i Ybe v produces water. Ybe Flathead e Qlk r Ybe Ybe Qao ALLUVIUM, OLDER (Holocene) - Light to dark brown and grayish brown sand, pebbles, cobbles, and minor silt and clay; upper surface Ybe T26N forms terraces near major stream valleys; topographic position intermediate between active stream valleys and areas of outwash deposition; Lake Ybe thickness ranges from 1 to 40 feet; ground water commonly near land surface; produces significant quantities of water.