Apsu - A compact surface NMR instrument for groundwater investigations

TY - GEN

T1 - Apsu - A compact surface NMR instrument for groundwater investigations

AU - Larsen, Jakob Juul

AU - Griffiths, Matthew

AU - Vang, Mathias

AU - Liu, Lichao

AU - Grombacher, Denys

N1 - Publisher Copyright: © 2021 Society of Exploration Geophysicists First International Meeting for Applied Geoscience & Energy

PY - 2021

Y1 - 2021

N2 - We have recently developed a new surface nuclear magnetic resonance (NMR) instrument, named Apsu. The instrument is designed with low weight and flexibility in mind. Our design differs from the commercial surface NMR instruments in several aspects. In particular, the instrument is based on an un-tuned transmitter coil, the NMR pulses are independently controlled at the half-cycle level and the instrument is powered from a generator. The modular instrument uses a 50 m x 50 m coil to transmit the NMR excitation pulse and receives the NMR signal in one or several small 9 m x 9 m receiver coils. Recently, the instrument has been updated to operate in coincident coil mode, so the transmitter coil can also be used to receive the NMR signal. For remote reference noise cancellation, the instrument can connect to multiple receiver units through WiFi. The effective peak current of the system is 105 A at a Larmor frequency of 2 kHz, which corresponds to approximately 30 m depth of investigation. We give an overview of the instrument and provide a field example from Kompedal Forest, Denmark.

AB - We have recently developed a new surface nuclear magnetic resonance (NMR) instrument, named Apsu. The instrument is designed with low weight and flexibility in mind. Our design differs from the commercial surface NMR instruments in several aspects. In particular, the instrument is based on an un-tuned transmitter coil, the NMR pulses are independently controlled at the half-cycle level and the instrument is powered from a generator. The modular instrument uses a 50 m x 50 m coil to transmit the NMR excitation pulse and receives the NMR signal in one or several small 9 m x 9 m receiver coils. Recently, the instrument has been updated to operate in coincident coil mode, so the transmitter coil can also be used to receive the NMR signal. For remote reference noise cancellation, the instrument can connect to multiple receiver units through WiFi. The effective peak current of the system is 105 A at a Larmor frequency of 2 kHz, which corresponds to approximately 30 m depth of investigation. We give an overview of the instrument and provide a field example from Kompedal Forest, Denmark.

UR - http://www.scopus.com/inward/record.url?scp=85120964784&partnerID=8YFLogxK

U2 - 10.1190/segam2021-3582046.1

DO - 10.1190/segam2021-3582046.1

M3 - Conference article

AN - SCOPUS:85120964784

SN - 1052-3812

VL - 2021-September

SP - 3135

EP - 3139

JO - SEG Technical Program Expanded Abstracts

JF - SEG Technical Program Expanded Abstracts

T2 - 1st International Meeting for Applied Geoscience and Energy

Y2 - 26 September 2021 through 1 October 2021

ER -