Robert SharpRobert P. Sharp (1911-2004) cowrote the first edition of this book when he was a professor emeritus at the California Institute of Technology (Cal Tech), where he taught generations of geology students, leading them on field trips across the state. H was an expert in sand dune physics and also planetary sciences. He received the Penrose Medal from the Geological Society of America, its highest honor, in 1977. Read More Read Less