Geologic timeline of Western North America

Timeline

A timeline is a way of displaying a list of events in chronological order, sometimes described as a project artifact . It is typically a graphic design showing a long bar labeled with dates alongside itself and events labeled on points where they would have happened.-Uses of timelines:Timelines...

of significant geological events in the evolution of western North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

. Dates are approximate. ("Ma" = millions of years ago)

Date	Period/Epoch	Event
350 Ma	Devonian Devonian The Devonian is a geologic period and system of the Paleozoic Era spanning from the end of the Silurian Period, about 416.0 ± 2.8 Mya , to the beginning of the Carboniferous Period, about 359.2 ± 2.5 Mya...	An unnamed terrane Terrane A terrane in geology is short-hand term for a tectonostratigraphic terrane, which is a fragment of crustal material formed on, or broken off from, one tectonic plate and accreted or "sutured" to crust lying on another plate... collides and accretes to the North American Plate North American Plate The North American Plate is a tectonic plate covering most of North America, Greenland, Cuba, Bahamas, and parts of Siberia, Japan and Iceland. It extends eastward to the Mid-Atlantic Ridge and westward to the Chersky Range in eastern Siberia. The plate includes both continental and oceanic crust... , along a line roughly coinciding with the Nevada-Utah border and called the Carlin Unconformity Carlin Unconformity The Carlin Unconformity or Carlin Trend is a geologic feature in northeastern Nevada which represents a period of erosion or non-deposition likely associated with a collision between a tectonic crustal block called a terrane and the North American Plate. The collision occurred during the... .
250 Ma	Permian Permian The PermianThe term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian...	The Sonomia Terrane Sonomia Terrane The Sonomia Terrane is a geologic crustal block known as a "terrane" whose remnants today lie in northwest Nevada. The terrane acquired its name from the Sonoma Range in that region. The Sonoma Terrane is associated with the Golconda Thrust, a formation named for its proximity to the town of... collides and accretes to the North American Plate, along a line called the Golconda Thrust (also the name of the event) which runs through central Nevada.
200 Ma	Triassic Triassic The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...	Sierra Nevada batholith Sierra Nevada Batholith The Sierra Nevada Batholith is a large batholith which forms the core of the Sierra Nevada mountain range in California, USA, exposed at the surface as granite.... first develops.
180 Ma	Jurassic Jurassic The Jurassic is a geologic period and system that extends from about Mya to Mya, that is, from the end of the Triassic to the beginning of the Cretaceous. The Jurassic constitutes the middle period of the Mesozoic era, also known as the age of reptiles. The start of the period is marked by...	The Intermontane Plate Intermontane Plate The Intermontane Plate was an ancient oceanic tectonic plate that lay on the west coast of North America about 195 million years ago. The Intermontane Plate had a chain of volcanic islands called the Intermontane Islands. The Intermontane Islands had been accumulating as a volcanic chain in the... collides with the Pacific Northwest, the remnants of which form the Intermontane Belt Intermontane Belt The Intermontane Belt is a physiogeological region in the Pacific Northwest of North America, stretching from northern Washington into British Columbia, Yukon, and Alaska. It comprises rolling hills, high plateaus and deeply cut valleys. The rocks in the belt have very little similarities with the... today.
165 Ma	Jurassic	The Smartville Block Smartville Block The Smartville Block, also called the Smartville Complex or Smartville Intrusive Complex, is a geologic zone in the foothills of the Sierra Nevada mountain range, in the historic Gold Country in eastern California.-Gold:... , an island arc terrane, collides and accretes to the North American Plate, along a line which coincides with the Mother Lode Mother Lode Mother lode is a principal vein or zone of veins of gold or silver ore. The term probably came from a literal translation of the Spanish veta madre, a term common in old Mexican mining... country of California.
140 Ma	Jurassic	Second wave of pluton Pluton A pluton in geology is a body of intrusive igneous rock that crystallized from magma slowly cooling below the surface of the Earth. Plutons include batholiths, dikes, sills, laccoliths, lopoliths, and other igneous bodies... s added to Sierra batholith.
115 Ma	Cretaceous Cretaceous The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...	The Insular Plate Insular Plate The Insular Plate was an ancient oceanic plate that began subducting under the west-coast of North America around the early Cretaceous time. The Insular Plate had a chain of active volcanic islands that were called the Insular Islands... collides with the Pacific Northwest. The remnants of that terrane comprise the Insular Belt Insular Belt The Insular Belt is a physiogeological region on the north western North American coast. It consist of three major island groups and many smaller islands and stretches from southern British Columbia into Alaska and the Yukon... today, of which Vancouver Island Vancouver Island Vancouver Island is a large island in British Columbia, Canada. It is one of several North American locations named after George Vancouver, the British Royal Navy officer who explored the Pacific Northwest coast of North America between 1791 and 1794... is a part.
90 Ma	Cretaceous	Third and last wave of plutons added to Sierra batholith.
43 Ma	Eocene Eocene The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...	The Pacific Plate changes its direction of motion from north to northwest.
35 Ma	Eocene	Rio Grande Rift Rio Grande Rift The Rio Grande Rift is a north-trending continental rift zone. It separates the Colorado Plateau in the west from the interior of the North American craton on the east. The rift extends from central Colorado in the north to the state of Chihuahua, Mexico in the south. The rift zone consists of four... begins to form.
20 Ma	Miocene Miocene The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...	San Andreas Fault San Andreas Fault The San Andreas Fault is a continental strike-slip fault that runs a length of roughly through California in the United States. The fault's motion is right-lateral strike-slip... comes into being as the North American Plate begins splitting the Farallon Plate Farallon Plate The Farallon Plate was an ancient oceanic plate, which began subducting under the west coast of the North American Plate— then located in modern Utah— as Pangaea broke apart during the Jurassic Period... in two.
17 Ma - 14 Ma	Miocene Miocene The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...	Columbia River Basalt Group Columbia River Basalt Group The Columbia River Basalt Group is a large igneous province that lies across parts of the Western United States. It is found in the U.S. states of Washington, Oregon, Idaho, Nevada, and California... Forms.
8 Ma	Miocene	Onset of faulting creating the Basin and Range Basin and Range The Basin and Range Province is a vast physiographic region defined by a unique topographic expression. Basin and Range topography is characterized by abrupt changes in elevation, alternating between narrow faulted mountain chains and flat arid valleys or basins... geologic province.
5 Ma	Miocene - Pliocene Pliocene The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...	Northward propagation of the East Pacific Rise East Pacific Rise The East Pacific Rise is a mid-oceanic ridge, a divergent tectonic plate boundary located along the floor of the Pacific Ocean. It separates the Pacific Plate to the west from the North American Plate, the Rivera Plate, the Cocos Plate, the Nazca Plate, and the Antarctic Plate... into the North American Plate initiates rifting off of the Baja California peninsula Baja California Peninsula The Baja California peninsula , is a peninsula in northwestern Mexico. Its land mass separates the Pacific Ocean from the Gulf of California. The Peninsula extends from Mexicali, Baja California in the north to Cabo San Lucas, Baja California Sur in the south.The total area of the Baja California... .
4 Ma	Pliocene	Sierra Nevada begins to rise.
3.5 Ma	Pliocene	The Pacific Plate Pacific Plate The Pacific Plate is an oceanic tectonic plate that lies beneath the Pacific Ocean. At 103 million square kilometres, it is the largest tectonic plate.... changes its direction of motion about 11 degrees east of its previous heading, from northwest to the present northwest by north.

External links

http://www.geog.ucsb.edu/~joel/g148_f06/readings/geol_history/geol_history.html
Dating of the Ages of Three Plutonic Episodes in the Sierras

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