2D Model Study of CO₂ Plumes in Saline Reservoirs by Borehole Resistivity Tomography

Table 3

Applied configurations for two vertical arrays, each of 16 electrodes (see Figure 2). The corresponding electrodes in each borehole are set at equal depths with unit interval.

Configuration	Data no.	Characteristics
(1) tp-p	813	Vertical current flow, horizontal resolution
(2) βh	1,240	Horizontal/lateral current flow, better data quality, better vertical (less lateral) resolution
(3) βl	14,440
(4) βhtp	2,053	Sum of βh and tp-p ((1) + (2))
(5) αvcs	1,796	Sum of Wenner and Schlumberger
(6) βvcs	1,177	Dipole-dipole
(7) αβvcs	2,973	Sum of αvcs and βvcs ((5) + (6))
(8) αvc	34,788	Comprehensive including nonstandard and standard (αvcs and βvcs in αvc and βvc, resp.) configurations
(9) βvc	31,510
(10) opt	3,000	Optimized data set with less than 4% size but 97% resolution relative to that of comprehensive set

c: circulating, v: vertical, α, β: tripotential configuration, l: lateral, s: symmetrical, tp-p: tripole-pole, h: horizontal, opt: optimized.