The Structure and Stratigraphy of the Upper Cretaceous Near Redding, California

Thick sections of Cretaceous deposits are exposed almost continuously along the west side of the San Joaquin-Sacramento Valley of California, as well as at its northern end, and also sporadically along the east side. Aside from noting their occurrence and collecting fossils from a few scattered localities, early workers did little with these sections. Since later work in the valley has been almost exclusively confined to the Tertiary, the Cretaceous has remained comparatively unknown, as evidenced by the fact that until just recently the entire Upper Cretaceous series of California has been grouped together under the single formation name of Chico. However within the last few years it has become apparent that there exist a number of distinct faunal zones within the recognized limits of the Upper Cretaceous. Because of the thickness and scattered occurrences of these deposits, their division and correlation has come to be recognized as a very complex problem, and an immense amount of work must be done before a reasonably complete and accurate section can be made. Various sections of Upper Cretaceous are found in the Santa Ana Mountains, Jalama Creek region, along the east side of Mt. Diablo, Tehama Creek, Redding, Chico Creek, Tuscan Springs, Folsom, Deer and Antelope Creeks, and various other places along the east side of the Sacramento Valley. The region near Redding has recently been the subject of investigation by Dr. W. P. Popenoe, who has already worked extensively with the Upper Cretaceous of the Santa Ana Mountains, and the present paper is a discussion of the structure and the stratigraphy of these beds, worked out in assisting Dr. Popenoe in his work at Redding. The field work was carried on during parts of July and August, 1936, and April and May, 1937. At this time the writer wishes to acknowledge his deep appreciation of the generosity and kindness of Dr. W. P. Popenoe, without whose unflagging interest and aid this work would not have been possible.