Medium Large Transport; Low Wing; 2 Turbojet Eng
Flight Crew Air Transport Pilot (ATP)
Confusion; Situational Awareness
Deviation / Discrepancy - Procedural Clearance; Ground Incursion Taxiway
Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented
Human Factors; Chart Or Publication
During takeoff brief discussed with First Officer the ambiguity of ramp diagram and past difficulty with determining the proper location of spots 105; 106; and 107 northwest [side] of the B gates at DFW.  We discussed our possible position after pushback and the possible directions we could go.  We also discussed that spots on ramp diagram do not match the actual spots on ramp.We pushed back off of the gate and were released with the nose pointing west; but slightly south. About a 260 degree heading.  We noted this as we discussed orientation on the ramp diagram.  Just to the right of the nose was spot 107. To the left of spot 107 about 100 feet was one of the spot 105 markings that was not on the ramp diagram. To the right were the three taxi lines associated with spot 107 (which we could see) and spots 106 and 105 (which we could not see).After the after start checklist; we informed ramp control we were unfamiliar with ramp and also asked for clarification on spot 105.  We made it very clear to ramp control that we were not familiar with this area of the ramp.  We emphasized it.  Ramp control stated that spot 105 was to our right.  We asked ramp about the spot 105 that was left of spot 107 which was slightly to our left.  Ramp control was unfamiliar with that spot and stated that spot 105 was to our right.So we taxied to the right and picked up the taxi line that I knew to be associated with spot 105 and we stopped at a taxiway hold short line that had no spot number at all.  We looked ahead and did see another spot 105 by another line and so we taxied to that spot 105. The only problem is that that particular spot 105 was right next to the centerline for Taxiway Z.  That means we encroached onto an active taxiway without clearance from ground.  The ramp diagram shows spots 105; 106; and 107 on the ramp side of the taxiway and clear of the taxiway.  This does not match the actual spot next to the taxiway centerline. All other spots on the ramp are on the ramp side of the taxiway boundary.  Except for these three spots.Another airplane was on taxiway G and cleared to taxi onto Z. They mentioned that our aircraft was on Z. That's about when we realized where the spots were placed.  The other airplane was not on our taxiway yet so there was no safety issue. We talked to ground control and explained the situation. He was understanding and gave us taxi clearance to our runway.With all the discussion and planning the First Officer and I did; this still occurred.  Because of the nonstandard spot markings; we taxied onto an active taxiway.  Spots 105; 10; and 107 are nonstandard in DFW as they are placed next to an active taxiway centerline instead of the ramp side of a taxiway boundary line; as all other spots are.To aggravate the situation; the spot placement on the ramp diagram chart; 60-7P-20; do not match the actual spots and the taxi lines do not match the actual lines. Also; there is only one spot 105 on the ramp diagram; but there are three spot 105's on the ramp and taxiway.First; move the spots 105; 106; and 107 away from the taxiway centerline and place them on the ramp side of the taxiway boundary line. Second; remove the redundant spot numbers that only add to the confusion of which is the correct spot. Third; fix the airport diagram so that it reflects the actual location of spots and each taxi line.
Air carrier Captain reports being cleared to spot 105 after push back from the B Concourse at DFW. Captain stated the spot numbers on the chart do not appear to correspond with the actual spot locations. After holding short of Taxiway Z at the hold bars; the reporter proceeds forward to a spot 105 marking encroaching active Taxiway Z without clearance.