The excited Ca(4s4d delta D-3(J))RG[(3)Delta(1,2)] states (RG=Ar, Kr, Xe) have been characterized spectroscopically by R2PI (resonance-enhanced two-photon ionization) spectroscopy. The main vibrational progressions, assigned to Ca(4s4d delta D-3(1))RG[(3)Delta(1)]<--Ca(4s4p pi P-3(0)). RG[(3)Pi(0)-] transitions, have weak subbands 3.7+/-0.5 cm(-1) to the blue which have been assigned to analogous transitions to the (3)Delta(2) upper states. For CaAr and CaKr, rotational analysis has confirmed this assignment. The (3)Delta(2)/(3)Delta(1) splitting is within experimental error the value expected if the molecular spin-orbit coupling constant is derived entirely from the Ca(4s4d D-3(J)) atomic contribution. This indicates that there is no "heavy-atom" mixing of RG(nd delta) character into the wave functions of the CaRG((3)Delta) states.