GSA Today
Volume 28

About the cover:
Early Jurassic Blue Lias Formation at Lyme Regis, Dorset, UK.  Abundant ammonite fossils form the basis for a highly resolved biostratigraphy that allows correlation of depositional sequences on regional and, in some cases, global scales. Photo by Steven Andrews, Camborne School of Mines, University of Exeter, UK. See related article, p. 4–10.

doi: 10.1130/GSATG359A.1

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