378 Adventures in Scenery 



joyed from the car seat. Just west of Goleta a large lagoon 

 indicates coastal sinking. 



Santa Maria and San Luis Structural 

 Valleys 



At Gaviota the highway turns away from the coast up a 

 canyon through Gaviota Pass, across the Santa Ynez Mountains 

 eight miles to Buellton on Santa Ynez River, thence through 

 and over the rolling Purisima Hills to Los Alamos, and through 

 Solomon Canyon 10 miles to Santa Maria Valley and Santa 

 Maria. The route is through the Santa Maria oil district. This 

 district is one of long sinuous folds or anticlines, and it is on 

 the axes of these folds that the productive wells are located. 

 The shales of the Monterey group are the probable source of 

 the oil. A large refinery is located at Gaviota, to which much 

 of the oil is conveyed by pipe lines. 



Dune sand rises high on the mountains, and encroaches on 

 the fertile farm lands of the broad alluvial Santa Maria Valley. 

 Santa Maria Valley is a "structural" valley. A clearly defined 

 terrace follows the north bank of the river, and the valley is 

 deeply filled with Pleistocene and alluvial deposits. Arroyo 

 Grande is at the mouth of a stream of that name which opens 

 out upon the alluvial plain of Santa Maria Valley. Four miles 

 west is Pismo Beach, once again at the ocean shore. Following 

 the beach five miles, Sycamore Springs is reached, at the mouth 

 of San Luis Creek. After a visit to the hot springs turn north 

 up San Luis Creek (an "antecedent" stream) which cuts 

 through the San Luis Range to the San Luis Valley. This val- 

 ley extends 20 miles northwest to the ocean, but has no stream 

 flowing lengthwise through it. It is drained mostly by Pismo 

 and San Luis creeks, which cut through the San Luis Range to 

 the sea. The valley is a structural valley lying between the 

 Santa Lucia Range on the northeast and the San Luis Range on 

 the southwest. 



San Luis Obispo, 228 miles (El. 243 feet) ; Santa Margarita, 



