  We show that the cycle map on a variety X, from algebraic cycles modulo
algebraic equivalence to integer cohomology, lifts canonically to a
topologically defined quotient of the complex cobordism ring of X. This more
refined cycle map gives a topological proof that the Griffiths group is nonzero
for some varieties X, without any use of Hodge theory. We also use this more
refined cycle map to give examples of torsion algebraic cycles which map to 0
in Deligne cohomology but are not algebraically equivalent to 0, thus answering
some questions by Colliot-Thelene and Schoen.
