Appearent error in Bondar calculation?

The map on the left shows a simple test case for traveltime estimations. Station BRVK, at the south end of the line, is in region R05c. Traveltimes for events close to this station should follow the R05c traveltime curve. As the line extends north into region R05b, the traveltime estimate should drift away from the R05c curve and move toward traveltime curve R05b. At great distance the Bondar estimated traveltime curve should approach R05b assumptotically.

Map of regionalization scheme in central Asia. Six of the proposed IMS stations are shown. The blue lines represents an imaginary array of sources being recorded at station BRVK (at the south end of the line). The axes are in kilometers and reflect the coordinate system used in the 3-D modeling described elsewhere. However, no raytracing is performed in this particular exercise. The south end of the blue line is in region R05c. The north end is in R05b.

Yellow tt curve: R05c Green tt curve: R05b Black solid tt curve: distance-weighted average Black dashed tt curve: Extracted from MRC traveltime calc.

Second example

Station MAK. Station is in R07. East end of line is in R11.

Yellow tt curve: R07 Green tt curve: R11 Black solid tt curve: distance-weighted average Black dashed tt curve: Extracted from MRC traveltime calc.