The youngest preserved lava flows of the Jurassic Kirkpatrick Basalt of the
Ferrar Large Igneous Province are unusually distinctive. These flows, reco
gnized in three geographic areas spread over 1600 km, have identical strati
graphic positions and geochemical characteristics. The lavas have an evolve
d, Fe-rich tholeiitic composition with lithospheric trace element ratios an
d enriched Sr-87/Sr-86 and Nd-143/Nd-144 isotope ratios. Except for the hig
hly mobile elements, the major, trace and isotopic compositions of lavas fr
om all these localities lie within, or near, analytical precision of each o
ther, and are distinct from other Ferrar rocks. Moreover, the ages of the B
ows at all localities are indistinguishable. The unique characteristics of
these capping lavas suggest that they were derived from a single batch of m
agma. Magma dispersal from a single reservoir through dike swarms at middle
to upper crustal levels is considered the most probable mechanism for larg
e-scale transport that extended for more than 3000 km. (C) 1999 Published b
y Elsevier Science B.V. All rights reserved.