402 Adventures in Scenery 



In the foothills along the east side of the valley are lava 

 flows, sandstones, shales, and clays of Tertiary age, also sand- 

 stones, shales and limestones of Jurassic age. Metamorphosed 

 sedimentary and igneous rocks in the foothills underlie the 

 auriferous (gold-bearing) gravels. 



Red Bluff at Northern End of 



Citrus Belt 



Red Bluff gets its name from the river bluff about 50 feet 

 high in which is exposed sands and gravels of Tertiary age. 

 These are the older alluvial sediments deposited in the bay that 

 filled the valley in late Cretaceous and Tertiary time, as distin- 

 guished from the later alluvium which has been deposited dur- 

 ing late Pleistocene time and down to the present, and which 

 comprises the present alluvial floor of the valley. Red Bluff is 

 at the northern end of the citrus belt. Oranges, lemons, 

 almonds, and figs are raised here, though fruit orchards, peaches, 

 pears, and prunes, occupy more extensive areas. 



Hot Springs; Volcanic Craters; 

 Sandstone Dikes 



Northeast of Red Bluff are the Tuscan Buttes, made up of 

 volcanic tuffs, gravel, sand and clay. Tuscan Springs, a health 

 resort, is nine miles northeast of Red Bluff. The springs, which 

 are hot, emerge from shale surrounded by volcanic tuff thrown 

 out from volcanoes in the Lassen Peak region. Directly east 

 of Anderson is Shingletown Butte, a perfect little extinct vol- 

 canic cone. Inskip Hill, a group of recent craters, lies to the 

 south of Shingletown Butte. A view of Lassen Peak may be 

 had from this section. 



Cotton wood Creek is crossed 17 miles north of Red Bluff. 

 It is of interest to note that 14 miles west on this creek are sand- 

 stone dikes, a not common geologic occurrence. Cracks in the 

 rocks that were formed by an ancient earthquake have been 

 filled with sand and the sand filling hardened into rock so that 

 the dikes resemble true igneous dikes. 



