Preliminary geologic maps showing Quaternary deposits of the lower Tuolumne and Stanislaus alluvial fans and along the lower San Joaquin River, Stanislaus County, California (Westley, Brush Lake, Ripon, and Salida 7.5 minute quadrangles)

1978 ◽  
Author(s):  
Denis E. Marchand ◽  
J.W. Harden
2001 ◽  
Vol 34 (1) ◽  
pp. 451
Author(s):  
Α. ΨΙΛΟΒΙΚΟΣ ◽  
Ε. ΒΑΒΛΙΑΚΗΣ ◽  
Κ. ΒΟΥΒΑΛΙΔΗΣ ◽  
Ε. ΠΑΠΑΦΙΛΙΠΠΟΥ-ΠΕΝΝΟΥ

On the S W foothills of Mt. Menikion and the NE part of Serres basin, four zones of composite alluvial fans have been formed. The upper zone of thick hard fanglomerates lies at altitudes of 280 to 600 m on Mt. Menikion schists and marbles. The high zone of loose fanglomerates, with red-brown sand matrix, lies at altitudes of 200 to 350 m on the neogene deposits. The intermediate zone of mixed coarse and fine elastics lies at altitudes of 80 to 140 m on neogene deposits. The lower zone of gravel, sand and silt deposits lies at altitudes of 10 to 60 m on quaternary terrace deposits. Each zone is approximately 13 - 17 km long and 1-2 km wide, with E/SE - W/NW trend, almost parallel to the main fault lines of the area. The fan zones were deposited along the slopes of Mt. Menikion and Serres basin, owing to the fault tectonics of the area. Several E/SE - W/NW trending parallel to each other listric faults, were formed on the basement on Mt. Menikion and the neogene deposits of Serres basin. Their blocks slided and turned downstream along the faults, so that their surface inclined backwards. Close to the faults, parallel valleys were formed. They filled up with quaternary deposits, brought down by activated torrents. The torrents flowed transversely to the fault blocks. At the inner parts of the blocks they deposited clastic material in the form of alluvial fans. In the outer – higher part of the blocks they were incised in the rocks or the neogene sediments, to form narrow valleys, with terraces along their walls. The staircase development of the relief finally resulted in a staircase development of the fan zones. The two zones, upper and high, seem to be Pleistocene in age and the torrents have already incised in the fan material. The two zones, intermediate and lower, seem to be Holocene in age and are still active. Tectonic activity seems to have been the main cause of sediment entrapment in the Serres basin and the low sediment delivery rate of the river Strymon during the Quaternary.


2017 ◽  
Vol 94 (3) ◽  
pp. 37-61
Author(s):  
Douglas R. Littlefield

Some histories of California describe nineteenth-century efforts to reclaim the extensive swamplands and shallow lakes in the southern part of California's San Joaquin Valley – then the largest natural wetlands habitat west of the Mississippi River – as a herculean venture to tame a boggy wilderness and turn the region into an agricultural paradise. Yet an 1850s proposition for draining those marshes and lakes primarily was a scheme to improve the state's transportation. Swampland reclamation was a secondary goal. Transport around the time of statehood in 1850 was severely lacking in California. Only a handful of steamboats plied a few of the state's larger rivers, and compared to the eastern United States, roads and railroads were nearly non-existent. Few of these modes of transportation reached into the isolated San Joaquin Valley. As a result, in 1857 the California legislature granted an exclusive franchise to the Tulare Canal and Land Company (sometimes known as the Montgomery franchise, after two of the firm's founders). The company's purpose was to connect navigable canals from the southern San Joaquin Valley to the San Joaquin River, which entered from the Sierra Nevada about half way up the valley. That stream, in turn, joined with San Francisco Bay, and thus the canals would open the entire San Joaquin Valley to world-wide commerce. In exchange for building the canals, the Montgomery franchise could collect tolls for twenty years and sell half the drained swamplands (the other half was to be sold by the state). Land sales were contingent upon the Montgomery franchise reclaiming the marshes. Wetlands in the mid-nineteenth century were not viewed as they are today as fragile wildlife habitats but instead as impediments to advancing American ideals and homesteads across the continent. Moreover, marshy areas were seen as major health menaces, with the prevailing view being that swampy regions’ air carried infectious diseases.


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