A geosteering control system, comprising: a processor enabled to access memory media; and the memory media storing instructions executable by the processor for: accessing reference well data associated with at least one reference well located in proximity to a subject well or associated with a section of the subject well, wherein the reference well data further comprises first measurement data describing at least one geological property versus true vertical depth (TVD); receiving second measurement data describing the at least one geological property for the subject well versus measured depth (MD); using a plurality of spline functions, mapping the second measurement data to the first measurement data; using a plurality of misfit functions, representing difference values in the at least one geological property between the second measurement data and the first measurement data as respectively mapped by the spline functions; and identifying a first spline function included in the plurality of spline functions as an optimal geosteering solution, wherein the first spline function is identified for having at least one minimum of the plurality of respective misfit functions; and based on the optimal geosteering solution, determining a subterranean location of a wellbore of the subject well during drilling of the subject well. a processor enabled to access memory media; and the memory media storing instructions executable by the processor for: accessing reference well data associated with at least one reference well located in proximity to a subject well or associated with a section of the subject well, wherein the reference well data further comprises first measurement data describing at least one geological property versus true vertical depth (TVD); receiving second measurement data describing the at least one geological property for the subject well versus measured depth (MD); using a plurality of spline functions, mapping the second measurement data to the first measurement data; using a plurality of misfit functions, representing difference values in the at least one geological property between the second measurement data and the first measurement data as respectively mapped by the spline functions; and identifying a first spline function included in the plurality of spline functions as an optimal geosteering solution, wherein the first spline function is identified for having at least one minimum of the plurality of respective misfit functions; and based on the optimal geosteering solution, determining a subterranean location of a wellbore of the subject well during drilling of the subject well. accessing reference well data associated with at least one reference well located in proximity to a subject well or associated with a section of the subject well, wherein the reference well data further comprises first measurement data describing at least one geological property versus true vertical depth (TVD); receiving second measurement data describing the at least one geological property for the subject well versus measured depth (MD); using a plurality of spline functions, mapping the second measurement data to the first measurement data; using a plurality of misfit functions, representing difference values in the at least one geological property between the second measurement data and the first measurement data as respectively mapped by the spline functions; and identifying a first spline function included in the plurality of spline functions as an optimal geosteering solution, wherein the first spline function is identified for having at least one minimum of the plurality of respective misfit functions; and based on the optimal geosteering solution, determining a subterranean location of a wellbore of the subject well during drilling of the subject well. <EOS>