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Arroyo Seco Canyon

(San Francisco Bay Region 3D image tour)

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The modern stream, Arroyo Seco, has incised a gorge within a broader floodplain surface in the valley. Additional older stream terraces can be seen along the valley sides throughout the valley.

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This view show gently eastward-dipping strata of the Monterey Formation (Miocene) exposed along the inner gorge of Arroyo Seco Canyon. The stream in this location is braided, suggesting that high sediment yields are common in times of flood. Note the broad, elevated stream terrace, and the higher, older terrace on the distant hillside.
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Lupine flowers cover fields on the first terrace in Arroyo Seco canyon. On the opposite side of the stream, nearly vertical beds of Monterey Formation crop out.
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Hogbacks of steeply, dipping Monterey Formation along Arroyo Seco Canyon crumble over time to form talus slopes.
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A bridge and gravel bar along Arroyo Seco just west of the entrance station to the campground/day-use portion of the preserve.
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Boulder of granitic rocks (Cretaceous?) form gravel bars along lower Arroyo Seco Canyon. Arroyo Seco drains the central Santa Lucia Range (including much of the Ventana Wilderness area). Cottonwoods attempt to colonize the gravel bars between infrequent but potentially massive flood events.
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Boulders trapped in the roots of the cottonwood suggest the tree has survived both floods and changes in the geometry of the gravel bar.
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This view is looking downstream from the entrance of the upper Arroyo Seco Gorge area in the park area.
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The main access road into the Ventana Wilderness is now off limits to vehicles. The old road was blasted into the granitic hillsides in this Santa Lucia range.
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This view is looking down from the wilderness access road into the gorge of Arroyo Seco. Clear water conditions most of the year are a result of a constant supply of spring water to the stream.
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Another view looking down into the gorge from the wilderness access road.
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Rock falls, both large and small, are common along Arroyo Seco Canyon, especially after winter storms.
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Last modified 11/24/2003