The Lompico Sandstone is a

sedimentary rock Sedimentary rocks are types of rock (geology), rock formed by the cementation (geology), cementation of sediments—i.e. particles made of minerals (geological detritus) or organic matter (biological detritus)—that have been accumulated or de ...

formation of lower to middle

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

age. It overlies the Salinian basement rocks of

Santa Cruz County, California Santa Cruz County (), officially the County of Santa Cruz, is a county on the Pacific coast of the U.S. state of California. As of the 2020 census, the population was 270,861. The county seat is Santa Cruz. Santa Cruz County comprises the Sa ...

. It interfingers with and is overlain by the Miocene

Monterey Formation The Monterey Formation is an extensive Miocene oil-rich geology, geological sedimentary formation in California, with outcrops of the formation in parts of the California Coast Ranges, Peninsular Ranges, and on some of California's off-shor ...

. These are in turn overlain by the mid to upper Miocene Santa Margarita Sandstone which is in turn overlain by the upper Miocene Santa Cruz Mudstone.

Hydrological importance

There are numerous occurrences of this

rock strata In geology and related fields, a stratum (: strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as ...

including coastal mountain ranges from Northern to

Southern California Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural List of regions of California, region that generally comprises the southern portion of the U.S. state of California. Its densely populated coastal reg ...

. In the coastal range of Santa Cruz County the formation has been documented in the

Zayante Creek Zayante Creek (Ohlone: ''Sayant'') is a stream within the San Lorenzo River watershed in Santa Cruz County, California, United States. The U.S. government has designated Zayante Creek as impaired with respect to sediment. Lompico Creek, a trib ...

watershed. The formation is often associated with

groundwater recharge Groundwater recharge or deep drainage or deep percolation is a hydrologic process, where water moves downward from surface water to groundwater. Recharge is the primary method through which water enters an aquifer. This process usually occurs in ...

areas.David C. Estrada, John Ricker, Robert Aston. 1979. ''San Lorenzo River Watershed management plan: hydrology technical section'', Santa Cruz County, California

Line notes

References

* C. Michael Hogan, Leda Patmore, David Crimp et al., ''San Lorenzo Basin Groundwater Recharge and Water Quality Study'', Earth Metrics Incorporated,

Association of Monterey Bay Area Governments The Association of Monterey Bay Area Governments (AMBAG) is a regional governmental organization which consists of representation of a large number of public agencies within Monterey County, Santa Cruz County and San Benito County, California. ...

, July 7, 1978 Neogene California Sandstone formations of the United States Geologic formations of California {{US-geologic-formation-stub

Hydrological importance

See also

Line notes

References