In recent years, lab based NMR core analysis researchers have begun to take advantage of enhanced signal-to-noise ratios (SNR) and shorter tau values to implement more data rich measurement techniques. In the past, extremely long acquisition times for T1– T2 maps, or correlation plots, made them next to impossible to obtain. Current SNR levels have eliminated this limitation and have allowed researchers to begin exploring what can be learned from these maps. Some examples of such measurements include spatially resolved T2, diffusion studies, and 2D correlation maps, or simply 2D NMR maps.
These maps currently are done in 3 versions:
- T1– T2 maps – used to give an indication of the fluid viscosity, fluid type and location of the fluid in the pore network.
- T2-Diffusion – used to separate oil and water and locate it in the pore structure.
- T2-Store-T2 – used to give an indication of the pore connectivity.
GIT’s 2D NMR maps provide the petrophysicists and reservoir engineers information about the fluids within the reservoir and the pore connectivity of the rock.
This information allows for better extraction plans. The NMR measurements are well suited to unconventional reservoirs such as shales, providing information the cannot be found any other way.
2D NMR mapping studies can be performed on samples using temperature to allow quantification of bitumen which too can assist technical experts in their understanding of their reservoirs.
GIT Systems Basic software allows users to perform the patent protected GIT 2D NMR map measurements on a gradient enhanced GeoSpec NMR instrument. Various field strengths can be used although using a higher field strength will speed up the measurement. Contact our sales team to find out more information about our NMR software and hardware products.
More information on T1 and T2 correlation maps for fluid typing and bitumen quantification can be found in this application note.