USGS Arizona Water Science Center Gravity Program Don Pool and Jeff Kennedy, USGS Brian Conway, Arizona Dept. Water Resources
Black Hills Limestone Aquifer Project DUSEL project
Sagehen Creek Sierra Nevada
ADWR PINAL AMA 19992007
Tucson basin storage change
Rillito Creek Ephemeral Channel Recharge AND GRAVITY AT WELL A-54 DEPTH TO WATER, FT 130 0.039 0.027 0.014 0.001 135-0.012 140-0.024 145 150 Jul-97 GRAVITY CHANGE, MILLIGAL WL GRAVITY BASIN TIES -0.037 Jan-98 Jul-98 Jan-99 Jul-99 Jan-00 Jul-00-0.050 Jan-01 First Ave Profile A-54 120 125 B-92 WL AND GRAVITY AT WELL B-92 GRAVITY 330 DEPTH TO WATER, FT 0.027 340 0.014 0.001 345-0.012 350-0.024 355 360 Jul-97-0.037 Jan-98 Jul-98 Jan-99 Jul-99 Jan-00 Jul-00-0.050 Jan-01 GRAVITY CHANGE, MILLIGAL 0.039 335 USGS
AND GRAVITY AT WELL A-54 120 DEPTH TO WATER, FT 130 0.039 0.027 0.014 0.001 135-0.012 140-0.024 145 150 Jul-97 GRAVITY CHANGE, MILLIGAL WL GRAVITY BASIN TIES 125-0.037 Jan-98 Jul-98 Jan-99 Jul-99 Jan-00 Jul-00-0.050 Jan-01 WL AND GRAVITY AT WELL B-92 GRAVITY 330 DEPTH TO WATER, FT 0.027 340 0.014 0.001 345-0.012 350-0.024 355 360 Jul-97-0.037 Jan-98 Jul-98 Jan-99 Jul-99 Jan-00 Jul-00-0.050 Jan-01 GRAVITY CHANGE, MILLIGAL 0.039 335
Gravity Change along First Avenue, Since Dec. 97 4/21/98 0.20 7/6/98 Floodplain South North Gravity Change, Milligal 0.15 0.10 Storage Gain 0.05 0.00-0.05 Storage Loss Rillito Creek -0.10 0.0 0.5 1.0 1.5 2.0 2.5 Distance, Miles 3.0 3.5 4.0 4.5
Gravity Change along First Avenue, Since Dec. 97 4/21/98 0.20 Floodplain South North Gravity Change, Milligal 0.15 0.10 Storage Gain 0.05 0.00-0.05 Storage Loss Rillito Creek -0.10 0.0 0.5 1.0 1.5 2.0 2.5 Distance, Miles 3.0 3.5 4.0 4.5
Gravity Change along First Avenue, Since Dec. 97 4/21/98 0.20 7/6/98 10/23/98 Floodplain South North Gravity Change, Milligal 0.15 0.10 Storage Gain 0.05 0.00-0.05 Storage Loss Rillito Creek -0.10 0.0 0.5 1.0 1.5 2.0 2.5 Distance, Miles 3.0 3.5 4.0 4.5
Gravity Change along First Avenue, Since Dec. 97 4/21/98 0.20 7/6/98 10/23/98 6/25/99 Floodplain South North Gravity Change, Milligal 0.15 0.10 Storage Gain 0.05 0.00-0.05 Storage Loss Rillito Creek -0.10 0.0 0.5 1.0 1.5 2.0 2.5 Distance, Miles 3.0 3.5 4.0 4.5
Gravity Change along First Avenue, Since Dec. 97 4/21/98 0.20 7/6/98 10/23/98 6/25/99 8/18/99 Floodplain South North Gravity Change, Milligal 0.15 0.10 Storage Gain 0.05 0.00-0.05 Storage Loss Rillito Creek -0.10 0.0 0.5 1.0 1.5 2.0 2.5 Distance, Miles 3.0 3.5 4.0 4.5
Gravity Change along First Avenue, Since Dec. 97 4/21/98 0.20 7/6/98 10/23/98 6/25/99 8/18/99 1/21/00 Floodplain South North Gravity Change, Milligal 0.15 0.10 Storage Gain 0.05 0.00-0.05 Storage Loss Rillito Creek -0.10 0.0 0.5 1.0 1.5 2.0 2.5 Distance, Miles 3.0 3.5 4.0 4.5
Gravity Change along First Avenue, Since Dec. 97 4/21/98 0.20 7/6/98 10/23/98 6/25/99 8/18/99 1/21/00 Floodplain South 6/2/00 North Gravity Change, Milligal 0.15 0.10 Storage Gain 0.05 0.00-0.05 Storage Loss Rillito Creek -0.10 0.0 0.5 1.0 1.5 2.0 2.5 Distance, Miles 3.0 3.5 4.0 4.5
Gravity Change along First Avenue, Since Dec. 97 4/21/98 0.20 7/6/98 10/23/98 6/25/99 8/18/99 1/21/00 6/2/00 Floodplain South 03/02/02 North Gravity Change, Milligal 0.15 0.10 Storage Gain 0.05 0.00-0.05 Storage Loss Rillito Creek -0.10 0.0 0.5 1.0 1.5 2.0 2.5 Distance, Miles 3.0 3.5 4.0 4.5
E:\Shared\gmsys\1ST21098 Gravity (mgals) 0.06 Generated with GM-SYS Fri Apr 25 17:04:44 2003 0.02-0.02 =Observed, -0.06 =Calculated -0.75 B92 Air D=0 WR52-0.7 A1B B91 A18 Depth (km) A54-0.65 STORAGE LOSS D=-0.2-0.6 1.6 V.E.=30 Scale=72683 5.6 Distance (km) 9.6
E:\Shared\gmsys\1ST31298 Gravity (mgals) 0.06 Generated with GM-SYS Fri Apr 25 17:32:31 2003 0.02-0.02 =Observed, -0.06 =Calculated -0.75 B92 Air D=0 WR52-0.7 A1B B91 A18 Depth (km) A54-0.65 STORAGE LOSS D=-0.2-0.6 1.6 V.E.=30 Scale=72683 5.6 Distance (km) 9.6
E:\Shared\gmsys\1ST42198 Gravity (mgals) 0.06 Generated with GM-SYS Fri Apr 25 17:40:53 2003 0.02-0.02 =Observed, -0.06 =Calculated -0.75 B92 Air D=0 WR52-0.7 A1B B91 A18 Depth (km) A54-0.65 STORAGE LOSS D=-0.2-0.6 1.6 V.E.=30 Scale=72683 5.6 Distance (km) 9.6
E:\Shared\gmsys\1ST53098 Gravity (mgals) 0.06 Generated with GM-SYS Sat Apr 26 11:29:43 2003 0.02-0.02 =Observed, -0.06 =Calculated -0.75 B92 Air D=0 WR52-0.7 A1B B91 A18 Depth (km) A54-0.65 STORAGE LOSS D=-0.2-0.6 1.6 V.E.=30 Scale=72683 5.6 Distance (km) 9.6
E:\Shared\gmsys\1ST070698 Gravity (mgals) 0.06 Generated with GM-SYS Fri Apr 25 18:10:45 2003 0.02-0.02 =Observed, -0.06 =Calculated -0.75 B92 Air D=0 WR52-0.7 A1B B91 A18 Depth (km) A54-0.65 STORAGE LOSS D=-0.2-0.6 1.6 V.E.=30 Scale=72683 5.6 Distance (km) 9.6
E:\Shared\gmsys\1ST081398 Gravity (mgals) 0.06 Generated with GM-SYS Fri Apr 25 18:16:18 2003 0.02-0.02 =Observed, -0.06 =Calculated -0.75 B92 Air D=0 WR52-0.7 A1B B91 A18 Depth (km) A54-0.65 STORAGE LOSS D=-0.2-0.6 1.6 V.E.=30 Scale=72683 5.6 Distance (km) 9.6
E:\Shared\gmsys\1ST102398 Gravity (mgals) 0.06 Generated with GM-SYS Fri Apr 25 18:21:17 2003 0.02-0.02 =Observed, -0.06 =Calculated -0.75 B92 Air D=0 WR52-0.7 A1B B91 A18 Depth (km) A54-0.65 STORAGE LOSS D=-0.2-0.6 1.6 V.E.=30 Scale=72683 5.6 Distance (km) 9.6
E:\Shared\gmsys\1ST012199 Gravity (mgals) 0.06 Generated with GM-SYS Fri Apr 25 18:31:27 2003 0.02-0.02 =Observed, -0.06 =Calculated -0.75 B92 Air D=0 WR52-0.7 A1B B91 A18 Depth (km) A54-0.65 STORAGE LOSS D=-0.2-0.6 1.6 V.E.=30 Scale=72683 5.6 Distance (km) 9.6
E:\Shared\gmsys\1ST062599 Gravity (mgals) 0.06 Generated with GM-SYS Fri Apr 25 18:39:42 2003 0.02-0.02 =Observed, -0.06 =Calculated -0.75 B92 Air D=0 WR52-0.7 A1B B91 A18 Depth (km) A54-0.65 STORAGE LOSS D=-0.2-0.6 1.6 V.E.=30 Scale=72683 5.6 Distance (km) 9.6
E:\Shared\gmsys\1ST081899 Gravity (mgals) 0.06 Generated with GM-SYS Sat Apr 26 11:41:51 2003 0.02-0.02 =Observed, -0.06 =Calculated -0.75 B92 Air D=0 PIMA WASH LEVEL WR52-0.7 ALLUV BASE IN WASH A1B B91 A18 Depth (km) A54 North First Copy of Air D-13-14 19BBB2 D=0 ALLUV BASE first break TERRACE G Stream shallow alluvium well wl stream alluvium TERRACE GRAVEL CONLG TOP Partial y SATURATEDRED CLAY&GRAV TOP -0.65 D=0.07 Base deep well sandywlzone Fl WL BR CLAY WL WL WL BH D=-0.2 UNSATURATED FL BASE D=0-0.6 second break Tinaja? 1.6 V.E.=30 Scale=72683 STORAGE LOSS BH WL RED CONGL TOP CONGL V. HARD RED SHALE TOP BH BOTTOM CASING 5.6 Distance (km) 9.6
E:\Shared\gmsys\1ST012100 Gravity (mgals) 0.06 Generated with GM-SYS Fri Apr 25 18:55:24 2003 0.02-0.02 =Observed, -0.06 =Calculated -0.75 B92 Air D=0 WR52-0.7 A1B B91 A18 A54 Depth (km) Ril ito -0.65 wl STORAGE LOSS D=-0.2-0.6 1.6 V.E.=30 Scale=72683 5.6 Distance (km) 9.6
E:\Shared\gmsys\1ST030603 Gravity (mgals) 0.06 Generated with GM-SYS Sat Apr 26 11:24:33 2003 0.02-0.02 =Observed, -0.06 =Calculated -0.75 B92 Air D=0 WR52-0.7 A1B B91 A18 A54 Depth (km) Ril ito -0.65 wl STORAGE LOSS D=-0.2-0.6 1.6 V.E.=30 Scale=72683 5.6 Distance (km) 9.6
Absolute Gravity Observations USGS Office
New Withdrawal Well Near USGS Office
SG Meter Gravity Record USGS Office
Spatial and temporal distributions of gravity change Largest changes (>40 microgal) Rapid change in areas with large periodic input Drainage over weeks to months Near ephemeral stream channels, large depth to water Porous rocks in high elevations Long-term trends Groundwater mining Change from GW to SW irrigation Smaller changes across broad areas of alluvial basins locally in areas of low porosity rocks