Friday Field Foto #32: Load structures in shallow-marine sediments

I went out to the coast recently for fun and was reminded of some photos I took a few years back of the rocks exposed along the beach cliffs. This week’s photo shows some fantastic loading features.

Unfortunately there is no person standing with this photo for scale, but the very convoluted boundary between the lower darker siltstone and the much whiter overlying sandstone is about 2-3 people high. These features are essentially recording the sinking of the white sediment into the darker sediment below. Think lava lamp. This little illustration here shows it nicely.

Load structures in the Purisima Formation, San Gregorio beach, California (© 2007 clasticdetritus.com)

Happy Friday!

See all Friday Field Fotos here.

See more photos and posts about sedimentary structures here.

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