We analyze a special smooth
projective variety Yh arising from some one-dimensional irreducible slices on the
SL2(ℂ)-character variety of a hyperbolic link in S3. We prove that a natural symbol
obtained from these one-dimensional slices is a torsion in K2(ℂ(Yh)). By using the
regulator map from K2 to the corresponding Deligne cohomology, we get some
variation formulas on some Zariski open subset of Yh. From this we discuss
a possible parametrized volume conjecture for both hyperbolic links and
knots.