See more from this Division: Topical Sessions
See more from this Session: Ancient Polar Ecosystems and Environments: Proxies for Understanding Climate Change and Global Warming
Abstract:
Very-fine to fine-grained sandstone, organic siltstone, carbonaceous shale, and rooted mudstone are the most common facies in these alluvial deposits while medium-to coarse-grained material is extremely rare. Ripples are the most common bedform and root-traces are nearly ubiquitous within sands, silts, and muds.
Thick fining upward successions are interpreted as meandering trunk channels. Rooted, erosionally based heterolithic sheet sandbodies composed of inclined couplets of fine-grained sand/mud and including mud-filled abandoned channels are interpreted as highly sinuous, ephemeral, tidally influenced meandering streams. Laterally stable ribbon sandbodies incised into either IHS or fine-grained floodplain deposits are interpreted as anastomosing channels, possibly on associated splay complexes. Non-channelized, fine-grained facies are interpreted as levees, crevasse splays, lakes, swamps, and paleosols.
Low-energy, highly-sinuous meandering and laterally-stable anastomosing channels appear to coexist in the Prince Creek Formation. Heterolithic sheet sandstones and ribbon sandbodies are often found stratigraphically at the same level, with multiple ribbons occasionally occupying the same horizontal plane. This architecture suggests evolving splay complexes adjacent to meandering channels or contemporaneous existence of meandering and anastomosing channels in this alluvial-deltaic system.
See more from this Division: Topical Sessions
See more from this Session: Ancient Polar Ecosystems and Environments: Proxies for Understanding Climate Change and Global Warming