The animated essay film “Archipelago” is partly documentary but mostly fiction, with poetry perhaps the more apt reference. Essentially, the work is an abstract meditation on Québec, the St. Lawrence River, and the waterway’s islands. Formally ambitious and undeniably accomplished, “Archipelago” has a distinct avant-garde sensibility and employs a diverse array of graphic approaches as it unfolds. The film’s dual narrators — one male, one female — engage in an oblique sort of dialogue, speaking in Godardian aphorisms and occasionally even offering a factual nugget. Sight & Sound describes “Archipelago” as “a freewheeling showcase of 12 animators deploying wildly different styles to evoke myriad moods, images and sensations connected, directly or tangentially, with Québec. Animation techniques overlap with live-action footage amid hallucinatory swirls of on-screen hand-written text; old maps, photographs and films —  most prominently a 1941 newsreel-style reportage — are presented, augmented, rotoscoped and distorted; the concrete morphs into the impressionistic.” Washington University’s Colin Burnett, who hails from Montreal, will introduce and discuss “Archipelago.”