What kind of geologic structure is the Palos Verdes Peninsula?

What kind of geologic structure is the Palos Verdes Peninsula?

As described in the Rancho Palos Verdes General Plan Natural Environment Element, the Palos Verdes Peninsula is underlain by a sequence of middle Miocene and younger bedded sedimentary rocks that are draped anticlinally over a core of Mesozoic schist “basement rocks.” Both the schist and sedimentary rocks have been …

What does a geologic map show you?

A geologic map shows the distribution of materials at or near the Earth’s surface. Rock types or unconsolidated materials are generally grouped into map units and depicted using different colors. A bedrock geological map shows the type of intact, solid bedrock at or near the earth’s surface.

What does Palos Verdes Peninsula represent?

The Palos Verdes Peninsula was originally part of enormous ranchos owned by Dominguez and Sepulveda. “Palos Verdes” is a Spanish phrase that roughly means “green stalks” or “green wood”.

How was Palos Verdes formed?

The Palos Verdes Peninsula is a tectonic fault block of seafloor sediments and volcanics draped atop a submerged mountain of metamorphic rocks that began rising out of the Pacific Ocean 1.5 million years ago. Lava flows erupted upon or within the ocean sediments during the early phases of deposition.

What type of mass wasting is the Portuguese Bend landslide?

The term geologists use to describe when bedrock tilts in the same direction of the slope is called adverse bedding and is a major cause for mass wasting events such as landslides. The Portuguese Bend Landslide is a combination of an earthflow, rotational and translational slide.

What formation makes up the majority of Palos Verdes?

The Altamira Shale is the oldest of three subunits of the Monterey Shale and underlies most of the area of the Palos Verdes peninsula.

What are the features of a geologic map?

A geologic map shows the types of rocks or loose sediments at or below Earth’s surface, along with their distribution. Geologic maps also illustrate the relative ages of, and physical relationships between, Earth’s materials.

What information is shown on a geologic map quizlet?

Geologic maps show the distribution of rocks at the Earth’s surface. Usually, the rocks are divided into mappable units that can be easily recognized and traced across an area. The divisions (contacts between units) are based on color, texture, or rock composition.

Why is Portuguese Bend unstable?

The ground failure over the years has been due to seaward-dipping strata, rock weakness and continual coastal erosion. Prehistoric landslides are believed to be so extensive that they destroyed the formation of higher wave-cut benches.

What strategy stabilized the Portuguese Bend landslide?

What strategy stabilized the Portuguese Bend landslide? Water drainage.

Where does the Palos Verdes Peninsula come from?

The Palos Verdes Peninsula is part of an extensive, mostly submarine terrane where Middle Miocene and younger sediments lie unconformably on a tectonically disrupted basement of Mesozoic Catalina Schist ( Platt, 1975; Howell and Vedder, 1981 ).

What kind of fault is the Palos Verdes fault?

The Palos Verdes fault is an oblique-slip fault, with a ratio of strike-slip to dip-slip of 10:1, a relatively small dip-slip component, but yet enough to a) create the Palos Verdes hills, b) uplift the Monterey Formation from a marine to a terrestrial setting and c) create 13 marine terraces via sequential uplift.

How tall are the terraces on Palos Verdes Peninsula?

As the Palos Verdes Peninsula rose above sea level, marine terraces formed around what was then an island. Woodring, Bramlette, and Kew (1946) identified a series of terraces of different ages at elevations ranging from near sea level up to 1,200 feet above sea level. They numbered the mapped terraces from 1 (youngest) to 13 (oldest).

What kind of surfaces are in Palos Verdes Estates?

Marine terraces make great flat surfaces for developers to build on, and most of the developments you see in Palos Verdes are built on uplifted marine terraces.