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University of California Publications in Geology [Vol. 9 



the overlying Oligocene beds contain water-worn fragments of coal 

 and sandstone of probable Tejon age which were evidently derived 

 from the underlying Tejon. Walnut Creek is only a short dis- 

 tance from the Tejon area south of Mount Diablo and conditions 

 are probably the same in both places. (See Figure 2.) 



Fig. 2. Section showing Tejon strata and associated rocks in the vicinity 

 of Walnut Creek, Concord Quadrangle. (After Lawson.) 



The following section through Cave Point was measured by Mr. 

 William Kew and the write]-. Figure 1 shows the relations 

 graphically. 



Section of the Te.ion Group South of Mount Diablo 



Chico sandstone and limestone. „ . 



Feet. 



(1) Conglomerate 5 



(2) Thin-bedded gray sandstone _ 20 



(3) Gray foraminiferal shale 75 



(4) Hard gray sandstone 40 



(5) Massive tan sandstone 20 



(6) Gray-green foraminiferal shale 25 



(7) Light-tan coarse sandstone with cavernous weathering, first 



bluff 125 



(8) Alternating soft sandstones and carbonaceous shales 200 



(9) Sandstones with interbedded shales 307 



(10) Thin-bedded sandstone 50 



(11) Shale with thin-bedded sandstone 63 



(12) Thin-bedded sandstone with Turritella uvasana beds on top 100 



(13) Massive soft sandstone with Turritella uvasana beds, second 



bluff 100 



(14) Massive tan sandstone, second bluff 390 



(15) Shale 100 



(16) Light gray sandstone 8 



(17) Carbonaceous shale and thin-bedded sandstone.. 45 



(18) Massive tan sandstone, third bluff 554 



(19) Carbonaceous shales and lignite 25 



(20) Massive tan sandstone 85 



(21) Blue shale 25 



(22) Massive tan sandstone 225 



Monterey sandstone 



Total 2587 



