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North Dakota Geological Survey Geologic Investigatio ns No. 135 Edward C. Murphy, State Geo logist Lynn D. Helms, Director Dept. of Mineral Resources " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " " Jud Ayr Za p Ma x Ray Le hr Kulm Nom e Le al Pag e Hop e Lo m a Ma za Yo rk Kno x My lo Kief Win g Rus o Ros s Mo tt Oa ke s Daz ey Oxb o w Alice Ane ta Pek in Tol na Gilb y Min to Pisek Adams Nec he Alsen Cal io Wale s Per th Can d o Cra r y Le ed s Balt a Rol la La nd a Dra ke Ve lva Uph a m Reg a n Hag u e Sole n Le ith Elgin Haz en But te Ryd er Gr an o Plaz a Dod g e Go lva Bea ch Tio ga Alamo Rha m e Ash ley Wish e k Ga ckle Ma r ion Dick ey Ve ron a Berlin Fo r be s Lu dd e n Hav an a Fo r ma n Miln o r Lisb o n Fin g al Or iska Rog e rs Sible y Me d ina Ken sa l Tap p en Daw so n Ste ele Tu ttle Bar ne y Dwig h t Col fax Hor a ce Amenia Arth u r Hun te r Bux to n Hat to n Fin le y Sha ro n Bow do n Cat ha y Har ve y La ko ta Ma n ve l Ard oc h Hoo p le Con wa y La nk in Hen se l Milt on Nek om a Mu n ich Cal vin Han n ah Sar les Bisb ee La wto n Edm o re Ob er o n Esm on d Kra m er Ove r ly Sou ris Ant ler Ber ge n Tow ne r Ban tr y Ma r tin Lin to n Car so n Almont Heb r on Cen te r Beu la h Me r ce r Ma ko ti Saw ye r Sur re y Car p io Tol ley Mo h all Por ta l Tay lor Reg e nt Hay ne s Ree d er Amidon Epp in g Noo n an Cro sb y Wilto n Ze e lan d La m ou re Edg el ey Mo n an go Gw inn er Elliot t She ld on Kat hr yn San bo r n Ping re e Walc ot t Kind re d Har wo o d Ga rd n er Gr an d in Le on a rd Buff alo Lu ve rn e Binf or d Ham b e rg Nia ga ra Em er ad o Ink ste r Gr af to n Dra yt on Cry sta l Ege la nd Bro cke t Ham p d en War wic k Ma d do ck Wolf or d Rol ett e St J oh n Ma xb a ss New bu r g Ga rd e na Balf ou r Lin co ln Fla sh e r Sta nto n Dou g las Ken m ar e Lo ra in e Fla xt on Lig nit e Buc yru s Am br os e Fo r tun a La ng d on Dee r ing Ma n nin g Ve n tu ria Fr e do nia Nap o leo n Cog sw ell End er lin Stre e te r Buc ha na n Rob in so n Mo o re to n Wyn dm e r e Ma n ta do r Ma p let on Cliffo r d Ma yv ille Por tla nd Mc He n ry She ye nn e Syke st on Mc Ville Mic hig a n Rey no ld s Th o mp so n La rim o re Edin b ur g Fa ir da le Mo u nt ain Ham ilt on Bat hg at e Cav ali er Walh a lla Han sb o ro Roc kla ke Dun se ith La ns fo rd Wes th op e Ana m oo se Vo lta ir e Go od r ich Haz elt on Bra dd o ck Ben ed ict Was hb u rn Ga rr iso n Des L ac s Ber th old Gle nb u rn She rw oo d Bow be lls Col um b us New Tow n Hal lida y Killde e r Belf ield Ga sco yn e Scr an to n Ma r ma r th Arn eg a rd Wild ro se Belc ou rt Ellen d ale Fu lle rt on Pillsb ur y Wim bl ed on Cle vel an d Woo d wo rt h Cou r te na y Pet tib on e Han kin so n Fa ir mo u nt Chr ist ine Dav en p or t Cas se lto n Ga les bu r g Han n af or d Gle nf ield Fe ss en d en Nor th wo o d Fo r dvi lle St T h om a s Osn a br oc k Brin sm a de Kar lsr uh e Gr an ville Mc Clu sk y Stra sb u rg Self rid ge New Sale m Pick City Und e rw oo d Rive rd a le Gla ds to ne Het tin ge r Alex an de r Gr ac e City Litc hv ille Mo n tp elie r Lid ge r wo od Gr ea t Ben d Arg us ville Tow er City Hur d sfie ld Pet er sb ur g Park Rive r Fo r t Ya te s Gle n Ullin Col eh ar b or Bur ling to n Don n yb ro ok Rich ar d to n Fo r t Ran so m Abe rc ro m bie Coo p er st ow n Min n ew au ka n Willo w C ity New Le ipz ig Tu rt le La ke Pow er s La ke Wh ite Ear th Dun n Cen te r Sou th Hea r t New Eng la nd New Roc kfo r d Fo r est Rive r Sta rkw ea th e r Spr ing Bro ok Chu r ch s Fe r ry Go lde n Va lle y Sen tin el But te Spir itw oo d La ke Pale rm o Gr en o ra ! 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( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! (! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! (! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( ! ( Red River Misso uri Knife Sheyenn e River James River Heart Souris River Bo is de Sioux Cannonb all Little M isso uri River River Little Yellowston e R. Muddy River River River Cedar Creek River Little M isso uri River James River River River Red River Red River Devils Lake Souris River Souris River Des La c River River LAKE SAKAKAW EA OAHE LAKE LAKE SAKAKAW EA Pembina Sheyenn e Red River ( / 85 ( / 85 ( / 2 ( / 2 ( / 52 ( / 52 ( / 83 ( / 83 ( / 2 ( / 52 ( / 83 § ¨ ¦ 29 § ¨ ¦ 94 § ¨ ¦ 29 § ¨ ¦ 29 § ¨ ¦ 94 § ¨ ¦ 94 E X T E N T O F C O A L B E A R I N G S T R A T A I N T H E S U B S U R F A C E E X T E N T O F C O A L S E A S T E R N E X T E N T O F W I L L I S T O N B A S I N μ 104 o R 10 0 W 103 o R 10 2 W R 96 W R 92 W 102 o R 94 W R 88 W R 84 W 101 o R 86 W R 80 W R 76 W R 78 W R 72 W 100 o R 68 W R 70 W R 64 W 99 o R 60 W R 62 W R 56 W 98 o R 10 4 W 46 o T 130 N 104 o R 10 0 W 103 o R 98 W R 10 2 W R 96 W R 92 W 102 o R 90 W R 94 W R 88 W R 84 W 101 o R 82 W R 86 W R 76 W R 74 W R 78 W 100 o R 68 W R 66 W R 70 W 99 o R 60 W R 58 W R 62 W R 56 W 98 o R 54 W R 52 W 49 o 49 o R 48 W R 54 W R 52 W 97 o 48 o T 162 N T 160 N T 158 N T 156 N T 154 N 47 o T 150 N T 148 N T 146 N T 144 N T 142 N T 140 N T 138 N T 136 N T 134 N 46 o T 132 N T 130 N 48 o T 162 N T 160 N T 158 N T 156 N T 154 N 47 o T 150 N T 148 N T 146 N T 144 N T 142 N T 140 N T 138 N T 136 N T 134 N T 132 N Figure 2. The distribution of shallow gas occurrences detected in groundwaters that are found within respective areas of interpolated sulfate/bicarbonate ratio across North Dakota. The frequency of wells with a shallow gas show is greater in areas delineated as having relatively lower sulfate/bicarbonate ratios. Geochemical Indicators of Shallow Gas in Groundwater in North Dakota Fred J. Anderson 2011 0 10 20 30 40 Miles 0 10 20 30 40 Kilometers Lambert Conformal Conic North American Datum 1983 1:1,000,000 Scale Cartographic Compilation: Elroy L. Kadrmas [Sulfate]/[Bicarbonate] Ratio in Groundwater 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 Geologic Symbols ! ( Ground-Water Wells with Detected Shallow Gas Occurrence Historical Area of Reported Shallow Gas in Water-Supply Wells Area of Gas Occcurrence, as determined from Recent Anecdotal Occurrences in Water-Supply Wells Eastern Extent of Williston Basin (Laird, 1956) Extent of Coal Bearing Strata in the Subsurface (Murphy, 2001) Township Boundaries County Boundaries Selected Major Rivers or Creeks City/Town Boundaries " City/Town Locations Wa ter Interstate Highway § ¨ ¦ 29 ( / 83 US Highway Misc Symbols Figure 1. Comparison of sulfate/bicarbonate concentration ratios in groundwater to shallow gas field screening results from selected wells across North Dakota. The highest methane concentration (reported in ppm as C1 in air) detected from wells in each county are compared against their respective average sulfate/bicarbonate ratios - as determined from available ground-water geochemical data. The number of shallow gas occurrences is greater, and are also in relatively higher concentrations, as the sulfate/bicarbonate ratio decreases. selected REFERENCES Anderson, F.J., Gudmunsen, C.B., Hall, B.N., Ries, A.J., Christensen, A.R., and Bubach, B.J., 2010, Locations of FID Shallow Gas O ccurrences in North Dakota, North Dakota Geological Survey, Geologic Investigations No. 128, 1:500,000 scale map. Anderson, F.J., 2010, Shallow Gas Geochemical Exploration Indicators in Ground-Water Wells in North Dakota, North Dakota Geological Survey, Geologic Investigations No. 92, 1:500,000 scale map. Anderson, F.J., 2009, Methane Occurrence in Glacial Buried-Valley Aquifer Systems in N orth Dakota, Geological Society of America 2009 Annual Meeting & Exposition, Abstracts with Programs , Vol . No . 4 1, No. 7, p. 214. Anderson, F.J., Shu rr, G.W., and Fischer, D.W., 2006, History, Geology, an d Potential Hydro- geochemical Indicators of Natural Gas Occurrence and Production from Quaternary Glacial Drift and Upper-Cretaceous Sedimentary Bedrock in North-Central North Dakota, North Dakota Geological Survey, Geologic Investigations No. 33, 25 p. Laird, W.M., 1956, The Williston Basin - A Backward Look with a View to the Future, First International Williston Basin Symposium, Bismarck ND, p. 14-22. Martini, A.M ., Walter, L.M. , Ku, T.C.W., Budai, J.M., McIntosh , J.C., and Schoell, M ., 200 3, Microb ial production and modification of gases in sedimentary basins-a geochemical case study from a Devonian shale gas play, Michigan basin: AAPG Bulletin, p. 1355-1375. McIntosh, J.C., and Martini, A.M., 2008, Hydrogeochemical Indicators for Microbial Methane in Fractured Organic-Rich Shales: Case Studies of the Antrim, New Albany, and Ohio Shales, in Hill, P. Lillis, and J. Curtis, eds., Gas Shale in the Rocky Mountains and Beyond: Rocky Mountain Association of Geolo gists 2008 Guid ebo ok CD, p. 162-174 . Murphy, E.C., 2001, Strippable Lignite Deposits of North Dakota, North Dakota Geological Survey, Miscellaneous Maps No. 34. NDSWC, 2010, North Dakota State Water Commission Onlin e G rou nd-Water In fo rm ation Sys tem: http://www. swc.state.nd.u s Shurr, G.W., Haggar, T., and Chadima, S.A., 2006, Exploration Strategies for U ltra-Shallow Microbial Methane on the Eastern Margin of the Williston Basin, American Association of Petroleum Geologists, National Meeting Abstracts Volume, Houston TX, p 99. Shurr, G.W., 2008, Shallow Biogenic Gas in Cretaceous Shale on the Eastern Margin of the Williston Basin, in Hill, P. Lillis, and J. Curtis, eds., Gas Shale in the Rocky Mountains and Beyond: Rocky Mou ntain As sociatio n o f Geologi sts 200 8 Gu idebook CD, p. 176 -1 98. VanVoast, W.A., 2003, Geochemical signature of formation waters associated with coalbed methane: AAPG Bulletin, v. 87, p. 667-676. in in DISCUSSION The geochemical distribution of ground-water chemistries (in the form of sulfate [SO4] to bicarbonate [HCO] ion ratio) favorable for the occurrence of methane (CH4 or C1) is presented on this map. In addition, the locations of ground-water wells (field screened between 2006 to 2010) have been plotted that contain methane. Data from 7,503 wells was extracted, averaged, and interpreted here as is from ground-water geochemical databases maintained by the North Dakota State Water Commission (NDSWC). The data used for the geochemical interpolation on the map is from many different individual sampling events and include data from sampling events as far back as 1932. Any well sampled with ground-water ion chemistry meeting previously identified shallow gas exploration criteria has been included. Data reported from all types of wells found across the state, including: domestic, stock, production, municipal, industrial, observation, and irrigation wells, were used in the geostatistical interpolation. Wells described as “unknowns” with reported sulfate and bicarbonate ion concentrations were also included for completeness. Well depths range across all shallow ground-water systems from as shallow as three feet to as deep as 3,277 feet with the majority of wells (>80%) completed to depths less than 300 feet. In the absence of methane detection through instrumental or analytical means, sulfate and bicarbonate ion concentrations have been demonstrated as valid proxy indicators for potential occurrences of methane. The ratio of these concentrations are predictive of ground-water chemistry favorable for the presence of methane in the shallow subsurface. Previous workers (Anderson, et. al, 2006, McIntosh and Martini, 2008, Martini, et.al., 2003, Shurr, et.al, 2006, Shurr, 2008, and Van Voast, 2003) have demonstrated empirically that sulfate ion concentrations less than 500 mg/L, coupled with bicarbonate ion concentrations greater than 400 mg/L, are indicative of groundwaters containing detectable concentrations of methane in shallow ground-water systems in the Dakotas. The interpolated sulfate to bicarbonate ratio distribution is plotted on this map for the purposes of shallow gas exploration and comparison with known areas of hydrocarbon resource occurrence and reported historical shallow natural gas occurrence. Areas where a good correlation exists between known hydrocarbon occurrence and areas shown to be favorable for the occurrence of methane (based on sulfate to bicarbonate ratios) include: 1) the western two-thirds of the state coincident with the existence of the Williston Basin, 2) the areas of measureable coal resources, and 3) areas historically (ca. 1900’s) reported to have had shallow gas in the shallow ground-water systems. These historic areas include Bottineau County (north-central North Dakota), and the LaMoure area (southeastern North Dakota). In addition, recent anecdotal reports of shallow gas in water wells have been recorded in north-central North Dakota. Areas recently identified by the NDGS to contain shallow gas through well field screening, sampling, and testing include McKenzie County, western Dickey, northeastern Ransom, and eastern Cavalier counties. Several smaller areas were also identified in Divide and Burke Counties (northwestern North Dakota) as well as Wells, Eddy, Foster, Kidder, Burleigh, and Emmons counties (central North Dakota). A comparison of shallow gas occurrences with areas of interpolated ground-water geochemistry data further supports the conditions of ground-water geochemistry that are favorable, and potentially predictive of methane occurrence. Comparing sulfate/bicarbonate ratios (i.e. low sulfate/higher bicarbonate concentrations in groundwater) from wells with detected shallow gas indicate that a greater number of wells with relatively higher methane concentrations, occur at the lower end of the sulfate/bicarbonate ratio spectrum (Figure 1). Further, the direct comparison of ground-water geochemistry across the state with wells that contain shallow gas demonstrates occurrences (Figure 2) tend to be found in areas of favorable ground-water geochemistries (i.e. low sulfate/ bicarbonate ratio). It is important to note that this geostatistical interpolation and hydrogeologic interpretation of shallow ground-water geochemistry groups the saturated shallow subsurface into one relatively homogeneous ground-water unit across the state. In actuality this unit consists of several discontinuous systems and aquifers which are most appropriately considered individually and at larger scales for typical hydrogeological studies. [SO4 2- ] [HCO3 - ] as is (CH4 or C1)
