Way up structure
Videos
A way up structure, way up criterion, or geopetal indicator is a characteristic relationship observed in a sedimentary or volcanic rock, or sequence of rocks, that makes it possible to determine wheth
Cross-bedding in Zion National Park, Utah. Both the tangential bases on the cross beds and the truncations of overlying layers can be used as a way up indicator.
A dinosaur footprint preserved in positive relief is a trace fossil indicating the bottom (or sole) of the bed (Lower Jurassic Moenave Formation, southwestern Utah).
Geopetal structure in bivalve boring in coral; bivalve shell visible; Matmor Formation (Middle Jurassic), southern Israel.
Sedimentary structures
Videos
Sedimentary structures include all kinds of features in sediments and sedimentary rocks, formed at the time of deposition.
Megaripple/dune, formed in the upper flow regime, from Utah
Wave ripple or symmetric ripple, from Permian rocks in Nomgon, Mongolia with "decapitation" of ripple crests due to change in current
Skolithos trace fossil (scale bar is 10 mm)
Soft sediment deformation (possibly a seismite) in Dead Sea sediments, Israel