550 GEORGE DAVIS LOUDERBACK 



and in the field they were not separated." The same is true of the 

 Bucks Mountain locality, although the sandstones there are said to 

 be "somewhat metamorphosed." The "Jurassic" shales of the Port 

 Orford area are sometimes referred to as "slaty shales." This 

 partially metamorphosed character, the association with the Dillard 

 formation, and the fact that they could not in the field at any locality 

 be separated in characters or appearance from the "Myrtle formation," 

 would suggest that they are really Dillard, or that the Dillard (Fran- 

 ciscan) is, in part at least, Jurassic. It is possible, however, that these 

 beds may lie stratigraphically (even unconformably) below the Fran- 

 ciscan, and a careful examination of the field to determine this point 

 is desirable. 



EXTENSION OF THE FRANCISCAN 



The Dillard not only may be looked upon as a northern extension 

 of the Franciscan, but is of particular interest as extending the area 

 in which obtained in toto that congeries of peculiar conditions of 

 sedimentation, life, vulcanism, and diastrophism which characterizes 

 the Franciscan of central California. According to Fairbanks, to 

 whom chiefly we are indebted for statements of the distribution of 

 these Franciscan conditions, "the farthest point to which it can be 

 traced southward is southern Santa Barbara County, where it dis- 

 appears beneath the Cretaceous." 1 Furthermore, "the series has 

 been recognized by the writer from central Santa Barbara County 

 northwestward through the Coast Ranges to the Klamath Mountains. 

 On the western slope of these mountains it has been traced to the 

 Oregon line, and it undoubtedly extends farther." 2 The present 

 investigation has extended the limit of the Franciscan about eighty- 

 five miles farther north and beyond the Klamath Mountain group, 

 and there it is found to pass under the Eocene sediments at the edge 

 of an extensive Tertiary province. It is possible that the Franciscan 

 conditions will not be found north of the present boundary, but even 

 with this limit, the known extent of this unique sequence of conditions 

 — about 600 miles along the coast — is quite remarkable. 



1 Bulletin of the Geological Society of America, Vol. VI (1895), p. 83. It may be 

 remarked that by "Cretaceous" Fairbanks means the Shasta-Chico series. He 

 considers the Franciscan entirely pre-Cretaceous. 



3 Journal of Geology, Vol. Ill (1895), p. 416. 



