Fan-deltas are, essentially, alluvial fans that build directly into a standing body of water with Gilbert-style internal structure.

Fan-delta SystemsFan-delta Systems

Photo by W. W. Little

Photo by W. W. Little

Gilbert-type DeltasGilbert-type Deltas

Gilbert-type fan-deltas consist of pro-delta fine-grained sediment that settles from suspension, overlain by coarse-grained foreset beds formed by avalanching down the delta front, and capped by coarse-grained, braided fluvial deposits.

Photo by W. W. Little

Photo by W. W. Little

Photo by W. W. Little

Photo by W. W. Little

Photo by W. W. Little

Photo by W. W. Little

Photo by W. W. Little

Photo by W. W. Little

Photo by W. W. Little

Photo by W. W. Little

Photo by W. W. Little

Video Demonstration of Fan-deltaic Sedimentation

• http://video.google.com/videoplay?docid=2680216606273899665