The data displayed below were collected during a joint project between the following departments at Montana Tech of The University of Montana: Geophysical Engineering and the Montana Bureau of Mines and Geology. The samples represent sandstones collected and analyzed for their potential use as proppant material.

General Information
Reference Hanson, A.M.,1952, Cambrian Stratigraphy in southwestern Montana: Montana Bureau of Mines and Geology, Memoir no. 33, p. 25-41.
Notes Typically, the lower part of the Flathead Formation has more potential than higher in the section where there is usually sandstone interbedded with shale and more clay present. Also farther north and west showed more promise than the south and eastern sections discussed in this paper.
Measured Section Details
Unit Symbol Name Township Range Section 1/4 Section Location Latitude Longitude Geomethod Datum Page Number Sub Unit Id Sandstone Description Grain Size Cementation Roundness Sorting Thickness (ft) Suitability
_f Princeton 08N 13W 14 C SW 1/4 sec. 14, SE 1/4 sec. 15, T. 8 N., R. 13 W. 46.44327164915 -113.1975313995 TRS-SEC NAD83 25 Tan- gray brown quartzite sandstone, interbedded w/ shale (purple to green, fissile) thin to medium bedded 51 no
_f Princeton 08N 13W 14 C 46.44327164915 -113.1975313995 TRS-SEC NAD83 25 Thin to massive bedded, tan and brown weathering, snadstone / quartzite medium to coarse poorly 63 maybe
_f Princeton 08N 13W 15 D SW 1/4 sec. 14, SE 1/4 sec. 15, T. 8 N., R. 13 W. 46.44306201065 -113.20780891 TRS-SEC NAD83 25 Tan- gray brown quartzite sandstone, interbedded w/ shale (purple to green, fissile) thin to medium bedded 51 no
_f Princeton 08N 13W 15 D 46.44306201065 -113.20780891 TRS-SEC NAD83 25 Thin to massive bedded, tan and brown weathering, snadstone / quartzite medium to coarse poorly 63 maybe
_f Silver Hill 05N 13W 34 sec. 34, T. 5 N., R. 13 W. 46.14306073705 -113.212141472 TRS-SEC NAD83 25 medium- massive bedded, vitreous quartzite, brown - gray-purple, steep cliffs mostly medium, some coarse subangular - angular poorly 132 no
_f Silver Hill 05N 13W 34 46.14306073705 -113.212141472 TRS-SEC NAD83 26 greenish/ purple-gray, cross bedded, thick bedded quartzite medium subangular - angular poorly 22 no
_p Hecla 03S 11W 2 Hecla District sec. 2 T. 3 S., R.11 W. Beaverhead county 45.6041268725 -112.927695971 TRS-SEC NAD83 26 Greenish gray quartzite fine 24 no
_f Hecla 03S 11W 2 45.6041268725 -112.927695971 TRS-SEC NAD83 26 light to dark brownish gray quartzite, interbedded hornfells - litharenite medium 7 no
_f Grasshopper Creek 09S 11W 11 D Cabrian section NW of Armstead in SE 1/4 se 11, T. 9 S., R. 11 W. 45.0628141416 -112.910778912 TRS-SEC NAD83 27 purple sandstone, formation continues with many covered sections fine well 2 maybe
_f Grasshopper Creek 09S 11W 11 D 45.0628141416 -112.910778912 TRS-SEC NAD83 27 purple to buff sandstone medium 3 maybe
_f Grasshopper Creek 09S 11W 11 D 45.0628141416 -112.910778912 TRS-SEC NAD83 27 quartzite sandstone, purple-pink-tan medium to coarse 15 maybe
_f Grasshopper Creek 09S 11W 11 D 45.0628141416 -112.910778912 TRS-SEC NAD83 27 quartzite sandstone, lenses and beds of pebbles coarse to pebbly poorly 13.5 maybe
_f Kate Creek On ridge between right and left fork of Kate Creek about 6 miles from Ike Rife Ranch near junction o 27 Partially covered, light gray sandstone with irregular masses and layers of medium gray quartzite fine - pebbly chert in areas, friable in others poorly 54 probably not
_f Ashbrough Canyon 09S 08W 27 North Side of Ashbrough Canyon on west side of Blacktail Deer Creek valley, about 15 miles south of 45.0214063868 -112.5689654695 TRS-SEC NAD83 27 White and light gray cross-bedded sandstone medium and coarse poorly 23 no
_f Ashbrough Canyon 09S 08W 27 45.0214063868 -112.5689654695 TRS-SEC NAD83 27 medium to thick bedded sandstone, lighter and finer toward top, cross bedding medium to coarse 27 maybe too pebbly
_f Ashbrough Canyon 09S 08W 27 45.0214063868 -112.5689654695 TRS-SEC NAD83 27 purplish - reddish gray, arkosic sandstone scattered angular quartz pebbles poorly 6 no
_f Camp Creek 2S 08W 20 4 miles East of Melrose, in sec . 20, T. 2 S., R. 8 W., 45.6488462947 -112.6193613665 TRS-SEC NAD83 28 Most of this unit is interbedded with shale. Medium bedded purplish gray quartzitic sandstone 7 no- probably shaley
_f Camp Creek 2S 08W 20 45.6488462947 -112.6193613665 TRS-SEC NAD83 28 Massive to thin bedded brownish gray, quartzite with varying bed thickness 25 no
_f Sheep Mountain 08S 03W 2 miles east of fork on South Fork of Green Horn Creek, T. 8 S., R. 3 W., Madison county 30 Brownish gray, rusty when weathered, quartzite 103 no
_f Whitetail Valley 02N 04W 11 5 miles northeast of Whitehall, sec 11, T. 2 N., R. 4 W., 45.94030083105 -112.067259406 TRS-SEC NAD83 30 Light-gray and pinkish gray quartzite, followed by covered material medium 12 no
_f Whitetail Valley 02N 04W 11 45.94030083105 -112.067259406 TRS-SEC NAD83 30 pinkish to brownish gray quartzite sandstone medium 9 no
_f Helena ridge east of first gate on Nelson Gultch 6 miles west of Helena 31 gray, pinkish/brownish/purplish gray medium bedded quartzite followed by 38 (ft) quartzite talus medium 81 no
_f South Boulder 01S 03W 21 West Side of South Boulder Creek sec. 21, T. 1 S., R. 3 W., Madison County 45.7348238567 -111.977802497 TRS-SEC NAD83 33 Medium bedded, light gray, pinkish and tan-gray, rusty stains medium to coarse poorly 40 maybe
_f South Boulder 01S 03W 21 45.7348238567 -111.977802497 TRS-SEC NAD83 33 medium bedded, brown and purplish gray then pinkish gray to tan sandstone medium hard 17 maybe
_f Wigwam Creek 07S 02W 36 S 1/2 sec. 36, T.7S., R. 2W., and N 1/2 sec. 1, T. 8 S., R. 2 W., 45.18168815935 -111.791626902 TRS-SEC NAD83 34 reddish brown to gray arkosic sandstone with 2 pebble beds followed by shale coarse poorly 16 no
_f Wigwam Creek 07S 02W 36 45.18168815935 -111.791626902 TRS-SEC NAD83 34 reddish brown to brownish gray, highly cross-bedded quartzite, some pebbly layers and thinly laminated sandstone poorly 13 no
_f Wigwam Creek 07S 02W 36 45.18168815935 -111.791626902 TRS-SEC NAD83 34 basal unconformity, reddish-brown to tan sandstone with some quartzite layers medium 14 maybe
_f Wigwam Creek 08S 02W 1 S 1/2 sec. 36, T.7S., R. 2W., and N 1/2 sec. 1, T. 8 S., R. 2 W., 45.1671623979 -111.791668198 TRS-SEC NAD83 34 reddish brown to gray arkosic sandstone with 2 pebble beds followed by shale coarse poorly 16 no
_f Wigwam Creek 08S 02W 1 45.1671623979 -111.791668198 TRS-SEC NAD83 34 reddish brown to brownish gray, highly cross-bedded quartzite, some pebbly layers and thinly laminated sandstone poorly 13 no
_f Wigwam Creek 08S 02W 1 45.1671623979 -111.791668198 TRS-SEC NAD83 34 basal unconformity, reddish-brown to tan sandstone with some quartzite layers medium 14 maybe
_f Townsend 07N 01E 34 3 miles due west of Townsend, S 1/2sec. 34, T. 7 N., R. 1 E., 46.31899645435 -111.58810785 TRS-SEC NAD83 35 quartzite and micaceous argillite (4:1), presence of impure sandstone, fine grained sills present 71 no
_f Townsend 07N 01E 34 46.31899645435 -111.58810785 TRS-SEC NAD83 35 vitreous quartzite, cross-bedded, ridge forming, fine to coarse well rounded quartz, angular flat argillite (pebbles) poorly 92 no
_f White Sulphur Springs 08N 07E 32 10 miles south of White Sulphur Springs sec. 32, T. 8 N., R. 7 E., 46.4106377767 -110.8779856725 TRS-SEC NAD83 36 rusty gray quartzitic sandstone coarse 7 maybe
_f White Sulphur Springs 08N 07E 32 46.4106377767 -110.8779856725 TRS-SEC NAD83 36 mostly covered but resembles above interval coarse 46 maybe
_f White Sulphur Springs 08N 07E 32 46.4106377767 -110.8779856725 TRS-SEC NAD83 36 Thin to medium bedded, pale -pinkish gray to rusty gray sandstone, locally quartzitic medium - coarse poorly 38 maybe
_f White Sulphur Springs 08N 07E 32 46.4106377767 -110.8779856725 TRS-SEC NAD83 36 Bedded, well exposed cliff, brown to flesh colored, mostly quartzite but some sandstone. coarse medium 45 no
_f Logan 02N 02E 36 North Side of Gallatin River near Logan, Gallatin County 45.88178167635 -111.419594524 TRS-SEC NAD83 37 Light gray and light pinkish, sandstone and quartzite medium -fine 20 maybe
_f Logan 02N 02E 36 45.88178167635 -111.419594524 TRS-SEC NAD83 37 light purple and tan-gray, medium to thick bedded sandstone and quartzite coarse up to 3/8 " poorly 11 probably not
_f Logan 02N 02E 36 45.88178167635 -111.419594524 TRS-SEC NAD83 37 medium bedded, flesh colored to light brown quartzite medium 6 maybe
_f Logan 02N 02E 36 45.88178167635 -111.419594524 TRS-SEC NAD83 37 thick bedded quartzite, purplish medium 4
_f Logan 02N 02E 36 45.88178167635 -111.419594524 TRS-SEC NAD83 37 Buff and pinkish buff sandstone 3
_f Logan 02N 02E 36 45.88178167635 -111.419594524 TRS-SEC NAD83 37 medium interbedded quartzite and sandstone medium to fine 9
_f Logan 02N 02E 36 45.88178167635 -111.419594524 TRS-SEC NAD83 37 quartzite medium 2
_f Logan 02N 02E 36 45.88178167635 -111.419594524 TRS-SEC NAD83 37 Sandstone and quartzite 5
_f Jourdain Creek 05S 01E 22 sec 22 &23, T. 5 S., R. 1 E., 8 miles NE of Ennis 45.38640026375 -111.586934256 TRS-SEC NAD83 38 argillaceous at top,thin to thick bedded purplish-gray quartzite and sandstone. medium to coarse 98 yes lack of info
_f Jourdain Creek 05S 01E 23 sec 22 &23, T. 5 S., R. 1 E., 8 miles NE of Ennis 45.38618545185 -111.5662599645 TRS-SEC NAD83 38 argillaceous at top,thin to thick bedded purplish-gray quartzite and sandstone. medium to coarse 98 yes lack of info
_f Arrowhead Mountain 14S 01W 28 sec 28, T. 14 S., R. 1 W., 44.58506172435 -111.730189541 TRS-SEC NAD83 39 covered brown and pinkish, sandstone and pebbly sandstone in soil pebbles 75 no
_f Cooke City 09S 14E 25 D SE 1/4 sec 25, T. 9 S., R. 14 E., 45.01597440455 -109.9257102835 TRS-SEC NAD83 40 sandstone interbedded with argillaceous sandstone and arenaceous shale fine 36 no
_f Cooke City 09S 14E 25 D 45.01597440455 -109.9257102835 TRS-SEC NAD83 40 Thin to thick bedded tan- gray sandstone, some fine grained purplish medium to coarse 75 maybe
_f Cooke City 09S 14E 25 D 45.01597440455 -109.9257102835 TRS-SEC NAD83 40 sandstone fine-medium maybe