The Field Notebooks series contains notes, measured sections, and slab descriptions written by Frank Lozo, scientists from his lower cretaceous team at Shell, and other notable geologists such as Helen Heanne Plummer, J.A. Taff, and J.S. Stone. Ranging in date from 1890 to 1968, these notes contain field trip logistics, personal notes, stratigraphic diagrams, slab descriptions, and observations from field trips and digs and across Texas. Field Notebooks are arranged chronologically by Field Trip. Many notebooks contain notes and observations from multiple trips.