The newest of Disneynature’s Earth Day tie-in docs begins like they all do, with the familiar silhouette of the company’s Cinderella Castle aurorally revealed as an exalted, immaculate iceberg. We might do well to wonder just what ecological future is portended by so much natural majesty lurking in shadows and posing as a corporate logo. (Paramount’s, at least, doesn’t presume to save the world.) But not now, while there still are octopi to ogle, along with so many other intimately photographed sea beasts — each apparently quite amenable to Pierce Brosnan’s storybookish narration. Directors Jacques Perrin and Jacques Cluzaud handle their sardine vortices and humpback breaches like Michael Bay handles explosions: at various speeds, from various angles, and dotingly enough to get frequently distracted from any pretense to coherent storytelling. Its script as porous and beleaguering as a fisherman’s net, “Oceans” offers more wonder than comprehension; why it needed as many writers as Snow White had dwarves must just be a case of that mysterious old Disney magic.