Geology: Geologic Map of Newhall Pass
Saugus Formation, undivided
Age: Late Pliocene – Early Pleistocene (3.6 – 1.806 Ma)
Stratigraphic name: Saugus Formation
Description: Slightly consolidated, poorly sorted, coarse-grained, cross-bedded sandstone and pebble conglomerate; chiefly nonmarine, but includes a few interbeds of marine and brackish water depositional environm… >>>
Reference: Alvarez, R.M. and K.R. Bovard, 2005, Preliminary Geologic Map of the Los Angeles 30′ x 60′ Quadrangle, Southern California: U.S. Geological Survey Open-File Report 2005-1019. 2668588.
Age: Piacenzian – Pleistocene – (2.841 – 0.8705 Ma)
Thickness: 0 – 1388m
Unit ID: 6343
Engineering Geology Elsevier
TrailsLake Tahoe. A dirt road was completed in the 1910s from what had been a pack trail. The Los Angeles Times declared El Camino Sierra complete in 1931, when the portion from Mojave to the Owens Valley, along modern US 395, was paved. During the late 19th century, the corridor of modern Route 14 was also in use by the Southern Pacific Railroad for two lines. The first is a line to connect Los Angeles with the Central Valley, via Tehachapi Pass. While significantly longer than the more direct Ridge Route (east of modern Interstate 5), Tehachapi Pass is lower than Tejon Pass along the Ridge Route, with a longer, less steep grade on the descent into the Central Valley. This rail line remains the primary rail line to connect southern and northern California in use today, now owned and operated by the Union Pacific Railroad. The second resulted when the Southern Pacific acquired the un-finished Carson and Colorado Railroad in 1900. The Southern Pacific built a standard gauge connector to the narrow gauge Carson and Colorado line from their main at Mojave. Although plans were to eventually convert this acquired line to standard gauge, most of the line was abandoned before the conversion was complete. However, the southern portion of this line is still active and used for connections to the Trona Railway. The Midland Trail was one of the first organized coast-to-coast trails in the United States. In the trail’s infancy, its routing changed numerous times. By 1925, the Midland Trail was established along what is modern State Route 168, joining El Camino Sierra in Big Pine. Other named trails that would eventually follow this route included the Theodore Roosevelt highway, and Grand Army of the Republic Highway. Parts of modern Route 14 continue to be signed with these names, and north of Los Angeles County is still officially designated “El Camino Sierra / Midland Trail” as well as the aforementioned “Aerospace Highway”.
U.S. Route 6U.S. Route 6 was extended from Greeley, Colorado to Long Beach, California on June 21, 1937. Most of this extension used the Midland Trail, although the route entered California from Nevada slightly north of the previous route of the Midland Trail, instead passing through Bishop. While being designated US 6, parts of modern Route 14 began to be upgraded to freeway standards. As part of the 1964 state highway renumbering, US 6 was truncated at Bishop. The portion of US 6 from Inyokern to Los Angeles was designated State Route 14. Previously the Route 14 designation was used for Artesia Boulevard and Lincoln Avenue, in the Los Angeles area, a portion of modern State Route 91. Between 1963 and 1975 significant portions of US 6/SR 14 were moved to a freeway alignment. The former routing south of Mojave (and the current routing to the north) is still known as Sierra Highway. The first freeway section, from just east of Solemint Junction to Red Rover Mine Road, was completed in 1963. Further portions in the intercanyon areas of Acton to Soledad Pass were completed by 1965. By 1966 the freeway was complete as far north as Avenue P-8 in Palmdale. The freeway was completed to Mojave by 1972. http://socalregion.com/geology/los-angeles-geology/scv_geology/ by Michael Ballard Geology
The following sections will give more detailed descriptions of each areas geology. Please feel free to ask any questions if you cannot find what you are looking for.