Flotsam Moraines is the moraines trailing northeastward from Mount Morrison

Mount Morrison (Victoria Land)

Mount Morrison is a mountain, 1,895 m, standing between Midship Glacier and the head of Cleveland Glacier a in Prince Albert Mountains, Victoria Land. Discovered by the Discovery expedition and named after J.D. Morrison of the Morning, a relief ship to the expedition....

, trapped in the ice eddies between Midship Glacier

Midship Glacier

Midship Glacier is a broad flat glacier filling the bulk of Alatna Valley and having its origin on the slopes of Mount Morrison to the south, in Convoy Range, Victoria Land. From 1957 this ice body was considered part of Benson Glacier...

 and ice from local mountainside glaciers, in Prince Albert Mountains

Prince Albert Mountains

The Prince Albert Mountains are a major mountain group in Antarctica over 320 km long. Located in Victoria Land, they run north-south between the Priestley and Ferrar glaicers....

, Victoria Land

Victoria Land

Victoria Land is a region of Antarctica bounded on the east by the Ross Ice Shelf and the Ross Sea and on the west by Oates Land and Wilkes Land. It was discovered by Captain James Clark Ross in January 1841 and named after the UK's Queen Victoria...

. So named by a 1989-90 New Zealand Antarctic Research Program (NZARP) field party from association with Jetsam Moraine

Jetsam Moraine

Jetsam Moraine is a thin, sinuous medial moraine that arcs smoothly for 6 nautical miles from a point near Mount Razorback to beyond the far side of Black Pudding Peak, in Prince Albert Mountains, Victoria Land. Its curved trajectory marks the contact between Benson Glacier ice and that of...

 and because all supraglacial moraines are "floating" on the glacier

Glacier

A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...

ice, and drift in a manner similar to marine flotsam and jetsam.