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Pico Formation
The Pico Formation is a Pliocene epoch stratigraphic unit and geologic formation in the greater Los Angeles Basin, the Santa Monica Mountains, and the Santa Susana Mountains, in Los Angeles County of Southern California. Geology It was formed during the Neogene period of the Cenozoic Era, and overlies the Repetto Formation.Blake, Gregg H. 1991. "Review of the Neogene biostratigraphy and stratigraphy of the Los Angeles Basin and implications for basin evolution," In: Biddle, Kevin T. (ed), "Active Margin Basins", AAPG Memoir 52, 319pp. Outcrops of the formation in Santa Monica Mountains National Recreation Area have produced fossil shark teeth from the Pliocene."Santa Monica Mountains National Recreation Area," Hunt, Santucci, and Kenworthy (2006); page 67. In addition to fossils, armored mud balls were found by Cartwright (1928) in possible fluvial or coastal deposits of the Pico Formation, though they were referred to as "pudding balls" in the article. Classification The und ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geologic Formation
A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of a geologic formation goes back to the beginnings of modern scientific geology. The term was used by Abraham Gottlob Wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neogene
The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period Mya. The Neogene is sub-divided into two epochs, the earlier Miocene and the later Pliocene. Some geologists assert that the Neogene cannot be clearly delineated from the modern geological period, the Quaternary. The term "Neogene" was coined in 1853 by the Austrian palaeontologist Moritz Hörnes (1815–1868). During this period, mammals and birds continued to evolve into modern forms, while other groups of life remained relatively unchanged. The first humans (''Homo habilis'') appeared in Africa near the end of the period. Some continental movements took place, the most significant event being the connection of North and South America at the Isthmus of Panama, late in the Pliocene. This cut off the warm ocean currents from the Pacific to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology Of Los Angeles County, California
Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology, and so is treated as one major aspect of integrated Earth system science and planetary science. Geology describes the structure of the Earth on and beneath its surface, and the processes that have shaped that structure. It also provides tools to determine the relative and absolute ages of rocks found in a given location, and also to describe the histories of those rocks. By combining these tools, geologists are able to chronicle the geological history of the Earth as a whole, and also to demonstrate the age of the Earth. Geology provides the primary evidence for plate tectonics, the evolutionary history of life, and the Earth's past climates. Geologists broadly study the properties and processes of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pliocene California
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58See the 2014 version of the ICS geologic time scale million years ago. It is the second and most recent epoch of the Period in the . The Pliocene follows the Epoch and is followed by the |
Foraminifera
Foraminifera (; Latin for "hole bearers"; informally called "forams") are single-celled organisms, members of a phylum or class of amoeboid protists characterized by streaming granular Ectoplasm (cell biology), ectoplasm for catching food and other uses; and commonly an external shell (called a "Test (biology), test") of diverse forms and materials. Tests of chitin (found in some simple genera, and Textularia in particular) are believed to be the most primitive type. Most foraminifera are marine, the majority of which live on or within the seafloor sediment (i.e., are benthos, benthic), while a smaller number float in the water column at various depths (i.e., are planktonic), which belong to the suborder Globigerinina. Fewer are known from freshwater or brackish conditions, and some very few (nonaquatic) soil species have been identified through molecular analysis of small subunit ribosomal DNA. Foraminifera typically produce a test (biology), test, or shell, which can have eithe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fernando Formation
The Fernando Formation is a Plio-Pleistocene marine mudstone, siltstone and sandstone formation in the greater Los Angeles Basin, Ventura Basin, and Santa Monica Mountains, in Los Angeles County of Southern California. Geology Outcrops of the formation in Santa Monica Mountains National Recreation Area have produced fossil shark teeth.Hunt, Santucci, and Kenworthy (2006). "Santa Monica Mountains National Recreation Area", page 67. Classification The underlying Repetto Formation is equivalent in age to the Fernando Formation, and some researchers consider it as well as the overlying Pico Formation to be a junior synonym based on benthic foraminifera Foraminifera (; Latin for "hole bearers"; informally called "forams") are single-celled organisms, members of a phylum or class of amoeboid protists characterized by streaming granular Ectoplasm (cell biology), ectoplasm for catching food and ot ... stages. Other researchers maintain that the Repetto and Pico Formations are di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Armored Mud Ball
An armored mud ball is a small sedimentary structure, formed in flowing water, which consists of a fragment of clay or mud that has been rolled by currents into a spherical shape, and which then becomes coated in a layer of sand, gravel or pebbles that serves to protect (armor) it against further breakdown. Armored mud balls can vary in size from less than a centimeters up to 50 centimeters in diameter. Typically, they are between 5 and 10 centimeters in diameter. Mud balls are known to form in many parts of the world, and armored mud balls can form in river, lake or marine environments. Under circumstances of rapid burial, armored mud balls can become incorporated into other sediments which subsequently form sedimentary rocks. Exposures of these lithified armored mud balls are very rare, but are known from a small number of locations around the world. Etymology The name "pudding balls" was originally given to these structures by geologist Lon D. Cartwright Jr. in 1928. However, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Santa Monica Mountains National Recreation Area
The Santa Monica Mountains National Recreation Area is a United States national recreation area containing many individual parks and open space preserves, located primarily in the Santa Monica Mountains of Southern California. The SMMNRA is in the greater Los Angeles region, with two thirds of the parklands in northwest Los Angeles County, and the remaining third, including a Simi Hills extension, in southeastern Ventura County. Overall administration is by the National Park Service, coordinating with state, county, municipal, and university agencies. The Santa Monica Mountains National Recreation Area preserves one of the best examples of a Mediterranean climate ecosystem in the world. It also protects one of the highest densities of archaeological resources in any mountain range in the world.National Park Service, ''Santa Monica Mountains National Recreation Area: Statement of National Significance'', ca. 2000, page 4 In size the Santa Monica Mountains National Recreation A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cenozoic Era
The Cenozoic ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterised by the dominance of mammals, birds and flowering plants, a cooling and drying climate, and the current configuration of continents. It is the latest of three geological eras since complex life evolved, preceded by the Mesozoic and Paleozoic. It started with the Cretaceous–Paleogene extinction event, when many species, including the non-avian dinosaurs, became extinct in an event attributed by most experts to the impact of a large asteroid or other celestial body, the Chicxulub impactor. The Cenozoic is also known as the Age of Mammals because the terrestrial animals that dominated both hemispheres were mammalsthe eutherians (placentals) in the northern hemisphere and the metatherians (marsupials, now mainly restricted to Australia) in the southern hemisphere. The extinction of many groups allowed mammals and birds to greatly diversify so that l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern California
Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural region that generally comprises the southern portion of the U.S. state of California. It includes the Los Angeles metropolitan area, the second most populous urban agglomeration in the United States. The region generally contains ten of California's 58 counties: Imperial County, California, Imperial, Kern County, California, Kern, Los Angeles County, California, Los Angeles, Orange County, California, Orange, Riverside County, California, Riverside, San Bernardino County, California, San Bernardino, San Diego County, California, San Diego, Santa Barbara County, California, Santa Barbara, San Luis Obispo County, California, San Luis Obispo and Ventura County, California, Ventura counties. The Colorado Desert and the Colorado River are located on Southern California's eastern border with Arizona, and San Bernardino County shares a border with Nevada to the northeast. Southern California's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58See the 2014 version of the ICS geologic time scale million years ago. It is the second and most recent epoch of the Neogene Period in the . The Pliocene follows the Epoch and is followed by the Epoch. Prior to the 2009 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Santa Susana Mountains
The Santa Susana Mountains are a transverse range of mountains in Southern California, north of the city of Los Angeles, in the United States. The range runs east-west, separating the San Fernando and Simi valleys on its south from the Santa Clara River Valley to the north and the Santa Clarita Valley to the northeast. The Oxnard Plain is to the west of the Santa Susana Mountains. Description Geography The Newhall Pass separates the Santa Susana Mountains from the San Gabriel Mountains to the east. Newhall Pass is the major north-south connection between the San Fernando and Santa Clarita valleys, and Interstate 5 and a railroad line share Newhall Pass. The Santa Susana Pass (containing SR 118) connects the Simi and San Fernando valleys, and separates the Santa Susana Mountains from the Simi Hills to the south. Santa Susana Pass State Historic Park is located in the Simi Hills, just south of the Santa Susana Pass, at the northwestern edge of the San Fernando Valley. The Santa S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
