Published online by Cambridge University Press: 16 January 2020
We prove the deformation invariance of Kodaira dimension and of certain plurigenera and the existence of canonical models for log surfaces which are smooth over an integral Noetherian scheme $S$.
The second author was partially supported by NSF research grants no: DMS-1300750, DMS-1265285, by a grant from the Simons Foundation; Award Number: 256202 and by the Research Institute for Mathematical Sciences, a Joint Usage/Research Center located in Kyoto University. The authors are grateful to an anonymous referee for many useful suggestions.