Abstract: Provided are systems, methods, and apparatus for using nuclear magnetic resonance (NMR) to detect a first material in the presence of a second material within a region of the Earth and within a static magnetic field (such as Earth's magnetic field). These inventions are uniquely suited to detect NMR signals from materials remotely located from a measurement device (e.g., below ice with the device above the ice). They are further useful in detecting first material having relatively short spin-lattice (T1) relaxation time in the presence of second material having longer T1 relaxation time (and therefore slower response to applied magnetic fields). Two pre-polarization currents are used to create pre-polarization magnetic fields stronger than the static magnetic field, each applied over a period of time between the first material's T1 relaxation time and the second material's T1 relaxation time, enabling different ways to null the NMR signal from the second material.

Abstract: Methods and systems for detecting a material within a region of the Earth are provided. The region may be under a surface of earthen formation, ice, snow, or water. The method may be practiced in a variety of applications, for example in an arctic region to detect oil spills, leaks, or seepages. The methods and systems may include using at least one coil to transmit a radio frequency (RF) excitation signal into the region of the Earth; and receive any NMR response signals to determine the presence of the material of interest.

Abstract: Methods and systems for detecting a material within a region of the Earth are provided. The region may be under a surface of earthen formation, ice, snow, or water. The method may be practiced in a variety of applications, for example in an arctic region to detect oil spills, leaks, or seepages. The methods and systems may include using at least one coil to transmit a radio frequency (RF) excitation signal into the region of the Earth; and receive any NMR response signals to determine the presence of the material of interest.