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21-628: Nojoqui has been described as “one of the most graceful waterfalls in California” and “the highlight of the scenic drive along U.S. 101 between the coast and Solvang.” The falls drop nearly 100 feet over a sandstone wall of the Jalama Formation . From the sign posted near the falls: "Unlike most waterfalls, which gradually erode upstream, the Nojoqui Falls have built outward from the cliff over time. Calcium and magnesium carbonate from rocks above

42-421: A greenish tinge in fresh, unweathered exposures; upon weathering they develop a variety of colors. A few beds of pebble conglomerates and limestone, dark gray and not pure, are also found, but the shales are predominant throughout, accounting for around 90 percent of the entire unit. In general, the sandstone layers become more common towards the top of the stratigraphic column, and the largest conglomerate bed

63-627: Is a sedimentary rock formation widespread in Santa Barbara County , California. Of late Jurassic to Cretaceous age, the unit consists primarily of shale with some interbedded thin layers of sandstone , conglomerate , and limestone . The type locality of the Espada Formation is in Hondo Canyon, near Point Arguello , as first described by Thomas Dibblee in his 1950 book on the geology of southwestern Santa Barbara County. While

84-700: Is exposed for approximately six miles. Other outcrops occur north of the Santa Ynez Fault, in the San Rafael Mountains along the Little Pine Syncline and along the Hildreth Fault. Characteristic shale beds within the Jalama are dark gray to black, micaceous , and often carbonaceous . Sandstones interbedded with the shales are arkosic , light gray to tan, and sometimes massive, as at the base of

105-536: Is in the highest part of the Espada, exposed north of the Santa Ynez River near its junction with Mono Canyon. The sandstones are composed of grains which are similar mineralogically to the underlying Franciscan Formation. The Espada Formation represents a long period of geologic history – tens of millions of years – in which sediments were deposited in warm, quiet water in a basin that was gradually subsiding. The water

126-406: Is rainfall-dependent and “usually dries up in summer.” In December 2014 multiple landslides closed the trail to the falls. The landslides occurred on 03 December 2014 at approximately 11:30 AM near the end of the trail. Seven hikers were in the area when the landslide occurred but there were no injuries and initial reports that they were trapped were false. The landslides were caused by heavy rain in

147-564: The Espada Formation , also of Cretaceous age, and in places on the older Franciscan Formation , which is probably of Jurassic age. In one location, in Nojoqui Canyon near the Nojoqui Falls, the Jalama is in conformable contact with the underlying Espada, indicating one area that remained submerged through the era. The Jalama formation is separated by overlying sedimentary layers by an unconformity most everywhere it has been found, as

168-667: The Late Cretaceous epoch , the unit consists predominantly of clay shale with some beds of sandstone . A particularly erosion-resistant sandstone within the unit forms the scenic Nojoqui Falls , in the Santa Ynez Mountains south of Solvang . The type locality of the Jalama Formation is in southwestern Santa Barbara County on the low ridgeline between Santa Anita and Bulito Canyons, within Hollister Ranch , near

189-698: The Paleocene is unrepresented in the fossil record in southern Santa Barbara County, and the stratigraphic sequence goes directly from the Cretaceous Jalama to Eocene units, including the Anita and Juncal Formations. In his 1966 book on the geology of the central Santa Ynez Mountains, Dibblee finds the Cretaceous Jalama Formation to be in conformable contact with the Eocene Juncal in the eastern part of

210-537: The Jalama formation was deposited has been inferred to have rotated approximately 90 degrees clockwise and moved northward along the coast from its former position nearer San Diego. This motion took place beginning in the early Miocene , during a period of deformation along the boundaries of the Pacific and North American Plates, a boundary represented today by the San Andreas Fault . The unit lies unconformably on

231-518: The Santa Ynez range, without mentioning the intervening Paleocene; in this portion of the unit there are no fossils to provide clues as to date. While the eastern part of the Jalama Formation is almost without fossils, some localities in the western part are richly fossiliferous, with Campanian age foraminifer and molluscan assemblages. At least one species – Lysis jalamaca , from an extinct genus of shallow-marine gastropod – has been named for

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252-452: The area. The falls are located one and a half miles east of Highway 101 approximately five miles south of Buellton and about 7 miles southwest of the city of Solvang via Alisal Road. The falls are at the end of a short trail south of the parking lot. Jalama Formation The Jalama Formation is a sedimentary rock formation widespread in southern Santa Barbara County and northern Ventura County , southern California . Of

273-455: The boundaries of the Pacific and North American Plates . The crustal block on which the Espada was deposited has been shifted northwestward along the plate boundaries and rotated approximately 90 degrees since the time of its deposition. Most of the movement took place recently, compared to the time of deposition – in the Miocene and Pliocene eras. As the block shifted northward, the formation

294-595: The crest of the Santa Ynez Mountains , and near the headwaters of Jalama Creek . The formation is found from this area eastward along the Santa Ynez Range in periodic outcrops, underlying either the Anita Shale (in the western portion of its range) or the Juncal Formation Shale (in the east). The largest outcrop in the Santa Ynez Range is along the north slope of the mountains near Santa Ynez Peak, where it

315-417: The falls continually dissolve in the stream water, then are deposited as this water evaporates from the rock around the falls. Stalactites in a cave grow in the same slow manner, and are made of the same type of rock, called travertine . Grooves in the main travertine deposit and a gently curved notch at the base of the falls have formed where the rock has dissolved once again into the stream." The waterfall

336-628: The type location more than forty miles to the west. The region of present-day Santa Barbara and Ventura County during the Late Cretaceous was submerged, and the depositional environment was one of a narrow shelf and submarine fans. The previously exposed Espada Formation , after a period of erosion, was now underwater, and began to receive layers of sediment which would become the Jalama Formation. Periodic episodes of deeper and shallower water resulted in finer and coarser sediments, respectively – shales versus sandstones. The crustal block on which

357-562: The type section on Hollister Ranch. Another interbedded unit occasionally encountered is a cobbly conglomerate, which outcrops on the north slope of the Santa Ynez Mountains south of Gibraltar Reservoir. The cobbles in this unit are detritus from a granitic source rock in a gray to brown matrix. The overall Jalama Formation varies in thickness from around 2,000 feet near the Romero Saddle north of Carpinteria, to about 4,000 feet at

378-647: The unit is 1,200 meters (3,900 feet) thick at the type locality, it is much thicker elsewhere; along the southern slope of the San Rafael Mountains it is exposed from its base to its top, where it is probably in conformable contact with the Jalama Formation , and the total thickness is around 5,300 meters (17,400 feet) – 5 kilometers (three miles) of uninterrupted sedimentary deposition that took place over 50 million years. The formation throughout its geographic range consists of layer upon layer of well-bedded argillaceous silty to sandy shales, with smaller interbeds of arkosic sandstone. The shales are generally brown with

399-489: The unit. Lysus jalamaca has been dated to between 70-75 million years before present, in the late Cretaceous. Other fossils found in the Jalama Formation, listed in Dibblee's 1950 book include six species of bivalves and one species each of gastropod and cephalopod. All of these are described as "abundant", with numerous others not listed; all are indicative of upper Cretaceous. Espada Formation The Espada Formation

420-474: Was also subject to folding , resulting in creation of structures such as the Mono syncline , which includes Camuesa Peak north of Gibraltar Reservoir, and the parallel Agua Caliente anticline . Relatively few fossils are found in the Espada, considering its extent and immense depth, but those that are found mostly indicate a Cretaceous age. Buchia piochii , found in the lowest part of the Espada, has been dated to

441-416: Was usually shallow, as indicated by the frequent sandstone beds (coarse sediment such as sand is deposited nearer shore unless carried far offshore by submarine landslides and other subsea mass movements). The Espada resembles some strata of the underlying Franciscan Formation , even though the two units may have been deposited at great distances from each other, and brought together by tectonic forces along

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