Sand Dollar Fossils - Southern California Los Padres Mountains Miocene Era

[ezeemonee]

Found these Echinoid / Sand Dollar fossils on a field trip with the Southern California Paleontological Society (SoCal Paleo).  Great trip to a moderately difficult-to-reach location in the Los Padres Mountains backcountry.  Interestingly, many of the sand dollars were mostly loose in sandy dirt although some had some soft or hard sandstone matrix still attached to them.  There were a wide variety of sizes from roughly pinky fingernail size up to slightly larger than a quarter.  Many were fragmented but a good percentage were whole.  Some were worn by erosion but others especially some of the fragments had great detail.  

 

These are likely genus Astrodapsis but not sure if I noted that correctly.  Verbally it was mentioned that these were from the Miocene era and also from the event flyer excerpt below.  

 

"The fossils are from the Upper Santa Margarita Formation. The Santa Margarita Formation has been dated to the Late Miocene to Early Pliocene Epochs based on the molluscs and foraminiferans that have been identified. The rocks of the Santa Margarita Formation are believed to have been formed in shallow marine waters (5-100 meter deep) with strong currents and minimum water
temperature of 18 degrees Celsius. Consider the environment that modern sand dollars live in.  How do those environments compare with what we know about the environmental conditions of the Santa Margarita Formation?"

[Wrangellian]

Nice haul!

Digging in loose sand - that has to be the easiest fossil collecting, besides just picking up loose fossils on the surface.

[Coco]

Can you make close-ups in natural light ? The result would be much better.

 

Coco

[ezeemonee]

I'll see if I can add some pics of some specimens in the sunlight later.  Some of the fragments have a lot of detail compared to the full specimens.  Thanks!