Rm. Lent et al., STRONTIUM ISOTOPIC GEOCHEMISTRY OF THE DEVILS LAKE DRAINAGE SYSTEM, NORTH-DAKOTA - A PRELIMINARY-STUDY AND POTENTIAL PALEOCLIMATIC IMPLICATIONS, Journal of paleolimnology, 17(1), 1997, pp. 147-154
A series of water samples (precipitation, surface water and ground wat
er) from the Devils Lake drainage basin in central North Dakota have b
een analyzed for their delta(18)O and delta D and Sr-87/Sr-86. The del
ta(18)O and delta D of snow and most ground water samples fall near th
e meteoric water line, with the ground water being isotopically heavie
r than the snow, indicating that a portion of the recharge must come f
rom non-winter precipitation events. One ground water and all the surf
ace water samples fall below the meteoric water line, demonstrating ex
tensive evaporation. The Sr-87/Sr-86 ratio of the snow is more radioge
nic than those of the ground water samples, indicating that the ground
water has increased its Sr-86 content by the dissolution of mafic roc
k in the aquifer. Stump Lake has a much more radiogenic Sr isotopic ra
tio than the waters of Devils Lake suggesting a source of water differ
ent from that of Devils Lake. The East Stump Lake water, on the other
hand, appears to be either a mix of Devils Lake and Stump Lake waters,
or Devils Lake water diluted with precipitation.