shoestring sand

A shoestring sand is a geological deposit characterized by its very long and narrow shape, found within mud or shale. These formations are essentially sand or sandstone bodies that are significantly elongated in one dimension compared to their width.1

Shoestring sands can form in various depositional environments. River systems, for instance, can create shoestring-shaped sand deposits that are typically oriented perpendicular to the shoreline. Similarly, beaches, coastal dunes, and barrier bars can also form these elongated sand bodies, but in these cases, they are parallel to the shore. Molasse deposits, which are formed in environments like beaches and river channels, also include shoestring bodies of sandstone. These sandstones are often calcareous or sideritic and can be classified as subgraywackes or protoquartzites.23