Surface Nuclear Magnetic Resonance Survey collected in Mud Creek, CO, USA

Data description Released here is a Vista Clara GMR dataset collected at Mud Creek, CO, USA. The data were collected 31 May 2012. The static field had an inclination and declination of 66.5° and 8.2°, respectively and a strength of 52 659 nT corresponding to a Larmor frequency of 2242 Hz. The instrument utilised a 30 ms FID pulse and 23 stacks were collected. The header data is included separately from the 23 stacks. The Ch. 1 transmitter loop was a 44 m sided square "noise-eight" loop whose coordinates are described in the file 44m.pwa. Two noise loops were incorporated in Channels 2 and 3 but in our experience are not necessary for this dataset. The subsurface conductivity was characterised by a TEM survey (not included in this data release). A Tikhonov style inversion using AarhusInv of the TEM data yielded an electrical conductivity model of: Rho (Ohm m) Thickness (m)164.5 4.33.7 5.847.4 15.58.4 705.4 An example inversion image using Akvo (https://github.com/LemmaSoftware/akvo) is provided in the file AkvoInversion.pdf. Additional details about the hydrogeological context of the survey area are available in Yager and Arnold, 2003. The data were published in Irons and Li, 2014, Section 6.1. File Description akvoInversion.pdf - Example inversion result of the dataset produced using Akvo. akvoInversion.csv - A CSV listing of the inversion result. 44m.pwa - A Yaml description of the transmitter coil data.pdf - A plot of the phased dataset using Akvo MuddyCreek31May_30msFID - GMR header file MuddyCreek31May_30msFID_x - Here 'x' represents a numeral from 1 to 23, each of these files contains a single stack of data. REFERENCES Trevor P. Irons, Yaoguo Li, Pulse and Fourier transform surface nuclear magnetic resonance: comprehensive modelling and inversion incorporating complex data and static dephasing dynamics, Geophysical Journal International, Volume 199, Issue 3, December 2014, Pages 1372–1394, https://doi.org/10.1093/gji/ggu323. Yager, Tracy J.B., Arnold, L. Rick, 2003, Hydrogeology of a Biosolids-Application Site Near Deer Trail, Colorado, 1993-99 : U.S. Geological Survey Water-Resources Investigations Report 03-4209, 90 p, https://pubs.usgs.gov/wri/wri034209/.