We calculate the unpolarized generalized parton distributions (GPDs) of
sea quarks in the proton at zero skewness by using a nonlocal
chiral Lagrangian. The one loop contributions from pseudoscalar mesons,
intermediate octet and decuplet baryons are included.
The three dimensional distribution of sea quark GPDs have been obtained.
The flavor asymmetries for sea quarks at zero momentum transfer,
as well as strange form factors are obtained from the GPDs. The results are comparable with
phenomenological extractions and lattice QCD.