Jeff Nichols’ psychological drama “Take Shelter” won the Cannes Film Festival’s 50th Critics’ Week Grand Prix on Thursday.U.S. indie also nabbed the Society of Dramatic Authors and Composers’ SACD prize. Toplining Michael Shannon and Jessica Chastain, the pic centers on a family man who experiences apocalyptic visions. Pic world preemed at Sundance and has been acquired by Sony Classics. Autralian helmer Justin Kurzel’s feature debut, “Snowtown,” about Australian serial killer John Bunting, nabbed the special mention of the jury president. “Snowtown” opened in Australia on May 19. It has also been acquired by French distribution outfit ARP Selection, and has sold to other territories. Pablo Giorgelli’s Argentine title “Las Acacias” won the CID/CCAS prize, which is backed by the Assn. of Independent Cinema for Distribution and the government’s Main Fund for Social Activities. Giorgelli’s film also snatched up the OFAJ (Very) Young Critics’ award from a jury of 24 French and German students. This year’s Critics’ Week marks Jean-Christophe Berjon’s last edition as artistic director. Berjon had been in that post since 2004 and will be succeeded by French film journo Charles Tesson. Cannes Critics’ Week jury was topped by South Korean filmmaker Lee Chang-dong.