u = {x, x^3, 0};
v = {0, 0, z2};
l = (u - v) t + v;
w = l /. Solve[xs xs + ys ys + (zs - 1)^2 == 1 /. Thread[{xs, ys, zs} -> l], t][[2]];
Manipulate[Show[
ParametricPlot3D[{Cos[u] Sin[v], Sin[u] Sin[v], 1 - Cos[v]}, {v, ArcCos[1 - z1], 0},
{u, 0, 2 Pi}, PlotStyle -> {Opacity[.3], FaceForm[Red, Yellow]}, Mesh -> False,
PlotRange -> {{-1, 1}, {-1, 1}, {0, 2}}],
Graphics3D[{Opacity[.3], Cuboid[{-1, -1, -.01}, {1, 1, .01}]}],
ParametricPlot3D[{u, u^3, 0}, {u, -1, 1}],
ParametricPlot3D[w /. z2 -> z1, {x, -10^3, 10^3}, PlotPoints -> 300]],
{z1, 0.1, 2}]
The same with a spiral instead of a cubic: