The Shasta County General Plan contains a Public Safety Element as required by Section 65302(g) of the California Government Code, which requires that General Plans include an element containing identification and appraisal of seismic and geologic hazards. The oldest rock in this part of the range is the Santa Monica Slate. [1], During the Cenozoic, the volcanic and deep water sedimentary Franciscan rocks were accreted to the edge of California and vast areas of marine sedimentary rocks deposited in the Central Valley and what would become the Transverse and Coast Ranges. Secure .gov websites use HTTPS Thick Miocene sediments formed in narrow seaways from the Pacific. They have a low shrink-swell potential, low to moderate water erosion hazard, and a low wind erosion hazard in bare areas (see TableVI-1). The Pastolla Muck, drained, 0 to 2 percent slopes and Pastolla muck, 0 to 1 percent slopes occupy a large portion of the area of the northern quadrants along the Tule River. The Modoc exploited collapse pits and lava tunnels, turning to Tule Lake for food (subsequent drainage has reduced the lake shoreline). Fast flowing rivers meant that the region has accumulated very little alluvium, except for a rare 400 foot thick deposit in Scott Valley, southwest of Yreka, California. These soils are relatively deep (40 to 60 inches), well drained gravelly loams with moderately slow permeability. The soils are very deep, well drained soils with moderately slow permeability and have a moderate shrink-swell potential (see Table VI-1). These habitats are a critical part of the Pacific flyway, supporting vast numbers of shorebirds and waterfowl, the densest wintering concentration of bald eagles in the world, and many other wildlife species. This project could not have been undertaken without the financial support of The Nature Conservancy's Oregon, Washington and California offices, and the Washington Department of Fish and Wildlife (WDFW). Fisher, once common in this ecoregion, now occurs only in the extreme southwestern portion of the East Cascades. Geology. Share sensitive information only on official, secure websites. Historically, 20 percent of the four million ounces of gold mined in California originated in the Klamath Mountains. Geology The Modoc Plateau and surrounding area is a predominantly rural region of northeastern California, southern Oregon, and northwestern Nevada, centered on the Modoc Plateau physiographic province ().In general, the Modoc study area is characterized by elevated heat flow (Williams and DeAngelo, 2011) and some 30 known geothermal systems as identified by thermal springs and wells (Faulds et al . The rocks likely formed much further away from the Sierras and were relocated by the dramatic movements of faults. High Cascades and the Modoc Plateau Road Guides 294. Pliocene and/or Pleistocene sandstone, shale, and gravel deposits; in part Miocene. In the nineteenth century, mining began in the vicinity of Julian, extracting nickel and gold, in the Julian Schist. Dominant land uses are forestry, livestock grazing, recreation and conservation. The latest edition of this popular book explores the state s recent rumblings and tremulous past with the aid of full color illustrations. About 85 percent of mercury produced in the US throughout its history was mined in the Coast Ranges, with about $200 million worth extracted between 1850 and 1980. Activities planned for the McArthur Swamp after the ownership transfer would not differ substantially from historic activities undertaken in the area since site reclamation earlier in the century. In southeast Oregon many domal complexes younger than 11 Ma exhibit a well-defined southeast to northwest age progression (Walker, 1974; MacLeod and others, 1976) from about 11 Ma to less than 1 Ma, Additional scientific data in this geographic area. At mid elevations, there are areas of Douglas-fir and grand fir (Abies grandis) forests to the north, and white fir and Douglas-fir forests to the south. The ditch was originally channeled out to increase flows to the Tule River for the Pit River Hydroelectric Project. These rocks were likely moved to their current location by the two major faults. It represents an ancient forearc basin that took shape as oceanic crust subducted under the west edge of the continent. Read more Print length 384 pages The California Coast Ranges extend from the Oregon line southward 600 miles to the Santa Ynez River. They have a Capability Class rating of IV and are considered Prime Farmland if drained and irrigated (NRCS, 2000). GitHub export from English Wikipedia. [4] and Modoc Cypress (Cupressus bakeri).[5]. It is in northeastern California about 50 km (31 mi) south of Klamath Falls, Oregon. As described under item (a), while various areas of the project site do consist of unstable soils, there are no facilities proposed as part of the project which have the potential to be impacted by these soils, therefore this is a less than significant impact. It formed as a sandspit filled in to the north from sediment deposited by the Tijuana River and sheltered from wind and waves by the Cretaceous uplands of Point Loma. They are bounded on the north by the Modoc Fault, which runs from Lake Murray to Georgia. They are derived from lake sediments and alluvium, which formed from extrusive igneous rocks. Water erosion hazard for bare soil is low to moderate, while the wind erosion hazard is low (refer to TableVI-1). These soils developed in basins from stratified alluvium of ash and lacustrine deposits. The soils are moderately to strongly alkaline and have a very high shrink-swell potential (refer to TableVI-1). Borehole Conditions The vault is a horizontal tunnel, located beneath 5 meters of overburden to maintain thermal stability. [14]. The Great Valley Sequence is a 40,000 foot thick formation at the western edge of the Central Valley that formed between the Jurassic and Cretaceous, overlying the Franciscan Assemblage and granite rocks associated with the Sierra Nevada to the east. Geologic units in Modoc county, California Additional scientific data in this geographic area Quaternary volcanic flow rocks, unit 1 (Cascade Volcanic Field) (Quaternary) at surface, covers 37 % of this area Quaternary volcanic flow rocks; minor pyroclastic deposits; in part Pliocene and Miocene. Policy SG-d - Shasta County shall develop and maintain standards for erosion and sediment control plans for development. Following the exchange, Burney Falls and Bowman Ditch will be protected from major construction and other soil disturbing activities by the legal restrictions applicable to State parklands. Includes rhyolite at Owyhee Dam, Jump Creek Rhyolite, and Littlefield Rhyolite, all of Kittleman and others (1965); Dooley Rhyolite Breccia of Gilluly (1937), radiometrically dated at 14.7 0.4 Ma by potassium-argon methods (Fiebelkorn and others, 1983); resurgent domal masses in McDermitt caldera area; and extensive unnamed flows and ash-flow tuffs in the central and southern part of the Owyhee Upland. We'll be adding other personal features soon. Since the active McArthur fault traverses the site, any displacement along this segment of the fault could result in potential fault rupture at the surface. The river drains a 612-square mile area, but due to the porous volcanic nature of the region, most of the stream flow originates from springs within the valley. The Kern River and San Joaquin River both run in valleys "refilled" with lava. Oil was first extracted in 1850 from the Pico Canyon field, close to Newhall with larger-scale production by 1875. Alluvium, lake, playa, and terrace deposits; unconsolidated and semi-consolidated. These soils are very deep (greater than 60 inches), very poorly drained, and mucky with slow permeability. Fossils are common in the marine rocks of the Pacific Beach and Mission Bay formation around San Diego. Major geologic changes began in the Cenozoic with continued continental shelf deposition of shale, sandstone and clay as well as near-shore tropical coal deposits. Basalt flows, plugs and dikes, some olivine basalt, and andesite and latitic rocks. Volcanic eruptions in the Miocene between 9.5 and 3.5 million years ago filled old eroded canyons in parts of the Sierras with lava flows. Both of these provinces have substantial geothermal resource base and resource potential. Geologists debate how high the early Sierra Nevada were. This is considered a less-than-significant impact. Shield volcanos. Use the interactive map to zoom smoothly from a national view to state and local perspectives anywhere across the country. You'll get a detailed solution from a subject matter expert that helps you learn core concepts. "Occasioned lakes, marshes, and sluggishly flowing streams meander across the plateau. From the oldest to the youngest, Georgia's provinces are the Piedmont, Blue Ridge, Valley and Ridge, Appalachian Plateau, and the Coastal Plain. The Modoc Plateau has a diverse geography, with portions draining into closed basins such as Goose Lake and Surprise Valley, and most of the remainder draining into the Pitt River, a tributary of the Sacramento River. In places includes talus and slope wash. Locally includes soils containing abundant organic material, and thin peat beds. Mostly nonmarine, but includes marine deposits near the coast. Many of the ash--flow tuffs exhibit flow features and only obscure vitro-clastic textures. Mineral materials found on the forest include obsidian and obsidian needles, petrified wood and assorted gemstones. In Washington and the rapidly developing areas around Bend in Oregon, timber companies have recently begun to sell their lands in the mid-elevation forest and transition zones to developers. Areas in the central portion of the northern half of the property contain the Henhill Silt Loam, partially drained, 0 to 2 percent slopes mapping unit. In Washington, much of the ecoregion is within the ceded lands and usual and accustomed fishing areas of tribes. Soils comprising the Burney-Arkright Complex, two to nine percent slopes mapping unit, occupy smaller areas in the eastern portion of the transfer property and are underlain by basaltic lava flows. Like the Sierra Nevada, the Peninsular Ranges have gentle western slopes and steep eastern faces. The area extends north to the Oregon border and south to include the Skedaddle Mountains and the Honey Lake Basin. Roadside Geology of Northern & Central California by David D. Alt and Donald W. Hyndman Only $25.99 Learn about the Geology of California with maps, photos and expert descriptions! Includes older alluvium and related deposits of Piper (1942), Willamette Silt (Allison, 1953; Wells and Peck, 1961), alluvial silt, sand, and gravel that form terrace deposits of Wells and others (1983), and Gresham and Estacada Formations of Trimble (1963). Includes some Mesozoic rocks. During the Jurassic, many sediments shed into the region from the rising proto-Sierra Nevada.