Ca Geology Chp 16 Transverse Range

Run transverse or crosswise to almost all of CA's other mountains & valleys. Highest peaks are San Gorgonio Peak in San Bernandino Mountains & San Antonio Peak in San Gabriel Mountains. Has valleys between them. BIggest are San Fernando & LA Basin

Coastline near here runs __ to ___ because in south coast. 4 northern islands called the Channel Islands for a chain. south islands too. The area offshore is referred to as Southern CA Borderland and is closely tied to the Transverse Range Province.

__ is the geologic process creating the features of the Transverse Ranges. This is because of the __ in the San Andreas fault making the Pacific & North American Plates converge at north south directions, which then creates the east to west uplift of mountains and push down of basins. It is __ and being squeezed.

Because the Transverse Range is compressional it consists of __ faults which __ the crust. One that only is slightly inclined is called a __. Sometimes they are hidden underground.

When rocks and sediments are compressed they can be crumpled together without rupturing to form ___ which consist of anticlines and synclines. These shorten crust too.

South CA's __ are regions where the crust has been tectonically depressed in the center & pushed up on all sides, forming a low-lying bowl or basin.

Some folds grow rapidly like the ___ Avenue anticline. San Joaquin Hills & Palos Verdes 10 meters up.

Geologists believe many S. CA's faults are still growing upward and have not yet broken the youger sedimentary layers near the surface. Recent earthquakes on blind reverse faults 1994 __ and 1987 Whittier Narrows.

Dramatic effect of compression in Transverse Ranges is formation of rapid filling of deep ___ during the past __ million years. As San Andreas fault evolved & Big Bend formed, the __ subsided and begin to fill with sediment. LA is filled to the brim above sea level with 5,5000 meters of sediment.

LA basin broken into for blocks. West Palos Verdes separates Palos Verdes Hillls from Long Beach-Wilmington. Newport-Inglewood NW. and East Whittier-Elsinore fault separating Puente Hills & San Gabriel Valley.

The __ basin is beneath the Santa Barbara Channel below sea level in the west and forms the surface of Santa Clara Valley & Oxnard Plain in east. Deepest of all basins of Transverse Ranges & world's thickest section of ___ marine deposits.

The Ventura Basins began to from in the ___ time 4 to 5 million years ago. Using sediments and microfossils like __, could check water depth of basin history. 1st subsidence was faster than filling sediment so water depth __. Later it was the opposite. We know because microfossils were from shallow waters (water depth __).

There were turbidites in the Pico Formation in Ventura Basin.

___ Formation one of the main sources of petroleum in CA because much of its silica-rich sediment is ___, a fine-grained sediment made from skeletal remains of marine Diatoms, a single-celled marine plankton. Used for filters (90% open space), absorbents, & insulation. CA supplies 60% of the world's ___.

Marine sedimentary rocks of late __ and early ___ age are present in the Santa Ynez, Topatopa, & Santa Monica Mountains, & Santa Ana Mountains. Uplifted, folded, falulted. Similar to Great Valley sequence in north so formed before San Andreas formed.

Ranges have large areas of granitic & metamorphic rocks. Of course, older basement rocks also overlie the Cenozoic basins of the Transverse Ranges Province. What are the four distinct blocks in the mountains?

There are two very different types and ages of basement rocks found in the San Gabriel mountains. Because of the ___ Thrust fault, the younger, but structurally lower Mesozoic Pelona schist subducted is the __ plate, and the older, but structurally higher pre-Cambrian block with Gneiss & plutons is the __ plate. This faulting violates the "normal" order of things.

Metasedimentary rocks in the __ Mountains were initially formed by deposition along the continetal margin of west North America 900-300 million years ago. The passive margin also extended through today's Basin and Range, Mojave Desert & Sierra Nevada. ___ tectonic events metamorphosed the sedimentary rocks to marble, schist that are exposed today.

CA's offshore islands. The northern islands were connected, forming a single large island named Santarosae. The Channel Islands were isolated from each other about 12,000 to 10,000 years ago because the ___ of sea level.

North of Avalon on Santa Catalina Island, native CA found ___, an impure variety of talc and used it to make distinctive bowls.

Marine terraces prominent in offshore islands, maybe the most complete sequence, San Clemente with 25 levels.

The four __ Channel Islands are the western extension of the __ Mountains. Rocks, folds, faults, match up. The Catalina schist is found on and named for Catalina Island, but it is not found on the other offshore islands.

The northern Channel Islands are composed mainly of ___ rocks of Miocene age, similar to thick sequences found in Santa Monica Mountains. Most by submarine eruptions.

1769, Gaspar de Portola saw Indians with tar/brea. Named place ___ near Ventura County where tar oozes from ground naturally. 1892 Edward Doheny & Charles Canfield found oil which began the big oil boom in LA.

World's first oil well drilled in ___ 1859 starting search for petroleum. 1st commerical well in Venura 1866. ___ Number 4 great well 150 barrels a day so created 1st oil pipeline in CA.

1900 more than 1,000 oil ocmpanies. Connection between anticlines, faults/folds & oil fields. Lots of people came. LA colorful place in 20th century.

1994 CA __ among U.S. oil producing states, but still small amount compare to annual use of U.S. Offshore drill increased CA production.

CA's __ history created ideal conditions for oil/gas resources. Transverse, offshore basins, & LA basins perfect.

Petroleum, which is oil & natural gas, is a combination of ___. Come from organic living matter from ___ organisms like ___ found in Monterey Formation which is the main source area.

Source rocks need to heat between __ to __ Celsius to form hydrocarbons. Occurs when buried by younger sediments & exposed to heat & pressure. Higher temperatures would convert them to something else. Heated properly, these rocks are known as ___.

Hydrocarbons migrate from source rock into rocks that can become saturated with petroleum. Petroluem-saturated __ rock is referred to as a pool, but not an underground lake of oil. It's a rock or sediment that has its pore space saturated with oil, natural gas, or both.

To accumulate as a pool or reservoir of petroleum, the hydrocarbon compounds must be trapped in the reservoir. __% of all petroleum formed escapes to the Earth's surface. What kind of structural traps are there to keep it from escaping?

What are the 4 environmental concerns of oil?

The Catalina schist, Pelona schist, & related Mesozoic formations were metamorphosed during ___ forming the basement rocks in the west. These rocks were ___ beneath North America during accretion & subduction & are equivalent to parts of the ___ complex in the Coast Ranges.

The Pacific & North American Plates touched about __ million years ago, creating the San Andreas. During the ___ time, the western Transverse Ranges were partly captured by the ___ moving Pacific Plate. Because the eastern part of the block remained fixed to North America, the western Transverse Ranges ___ more than __ degrees.

What is the evidence it rotated?

The Miocene rotations caused ___ creating new sedimentary __ in LA basin, Inner Borderland, & Santa Maria basin. Deposition of San Onofre Breccia which derived from mountains containing schist, signaled the creation of these basins. Miocene __ activity in the area of today's ___ Mountains & ___ Islands are a result of the crustal ___.

Oldest rocks in region are gneiss, schist, & plutonic rocks found in today's San Gabriel & San Bernardino Mountains. Oldest are 1.7 billion years old & thought to be related to N. America's ancient core.