Cenozoic Earth History. The Cenozoic Era Spans the time from 66 Ma until nowSpans the time from 66...
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Transcript of Cenozoic Earth History. The Cenozoic Era Spans the time from 66 Ma until nowSpans the time from 66...
Cenozoic Earth HistoryCenozoic Earth History
The Cenozoic The Cenozoic EraEra
• Spans the time from 66 Spans the time from 66 Ma until nowMa until now
• Is sub-divided into the Is sub-divided into the periods and epochsperiods and epochs
• Experienced 1 marine Experienced 1 marine transgression, the transgression, the Tejas Tejas
• Another transgression Another transgression began ~ 16,000 years began ~ 16,000 years ago ago
Geologic Provinces of North AmericaGeologic Provinces of North America
Rift Basins Rift Basins and and
Magnetic Magnetic Highs along Highs along
the East the East Coast of Coast of
North North AmericaAmerica
What do the What do the two ridges of two ridges of magnetic highs magnetic highs represent?represent?
The eastern margin of North The eastern margin of North America is America is
presently a passive continental presently a passive continental margin margin
What geologic events would suggest subduction has begun?
But ultimately oceanic crust will break along the But ultimately oceanic crust will break along the continental continental margin and subduction of Atlantic basin crust will margin and subduction of Atlantic basin crust will beginbegin
But ultimately oceanic crust will break along the But ultimately oceanic crust will break along the continental continental margin and subduction of Atlantic basin crust will margin and subduction of Atlantic basin crust will beginbegin
Geologic Provinces of the Southern Geologic Provinces of the Southern AppalachiansAppalachians
Fall ZoneFall Zone
• Comprises a thick sequence of Comprises a thick sequence of sediments deposited on top of sediments deposited on top of the Appalachian crystalline rocks the Appalachian crystalline rocks by the Zuni (Cretaceous) and by the Zuni (Cretaceous) and Tejas (Eocene) transgressionsTejas (Eocene) transgressions
• The Cretaceous and Eocene The Cretaceous and Eocene strata crop out the farthest strata crop out the farthest inlandinland
• The ACP strata are progressively The ACP strata are progressively younger and thicker toward the younger and thicker toward the coastcoast
The Atlantic Coastal PlainThe Atlantic Coastal Plain
Evolution of the Atlantic Coastal Plain Evolution of the Atlantic Coastal Plain Following Maximum Advance of the Tejas Following Maximum Advance of the Tejas
TransgressionTransgression• The Tejas Transgression began in the Paleocene, The Tejas Transgression began in the Paleocene,
peaked in the Eocenepeaked in the Eocene, having advanced as far inland , having advanced as far inland as where Augusta, Columbia, Raleigh, Richmond, and as where Augusta, Columbia, Raleigh, Richmond, and Philadelphia are now locatedPhiladelphia are now located
• As sea level receded following maximum As sea level receded following maximum transgression: transgression: – Erosion began sculpting a stair-step series of Erosion began sculpting a stair-step series of
• scarpsscarps ((paleo-shorelinespaleo-shorelines)) and and • terracesterraces ((wave-scoured sea floorwave-scoured sea floor))
– Acidic groundwater began forming numerous Acidic groundwater began forming numerous caves caves and sinkholes in the Santee limestoneand sinkholes in the Santee limestone
– Thousands of Thousands of Carolina BaysCarolina Bays were formed on the were formed on the Middle and Lower coastal plainsMiddle and Lower coastal plains
The The Atlantic Atlantic Coastal Coastal Plain Plain
Scarps and Scarps and Terraces Terraces
The ACPSandhillsThe ACPSandhills
Peachtree RockPeachtree Rock
A remnant of tidal inlet sands deposited near A remnant of tidal inlet sands deposited near Columbia during maximum advance of the Tejas Columbia during maximum advance of the Tejas TransgressionTransgression
Santee Santee LimestoneLimestone
was was deposited in deposited in deeper water deeper water
on the on the continental continental
shelf as sands shelf as sands that formed that formed Peachtree Peachtree Rock were Rock were
deposited at deposited at the coastthe coast
The core (a) The core (a) Was drilled Was drilled at Pregnallat Pregnall
Sinkholes (irregularly-shaped depressions) formed in Sinkholes (irregularly-shaped depressions) formed in Santee Limestone near Eutaw Springs, SCSantee Limestone near Eutaw Springs, SC
Sinkhole and Cave at Santee State Park, Sinkhole and Cave at Santee State Park, SCSC
A caveA cave forms as acidic water slowly dissolves limestonecidic water slowly dissolves limestone
A sinkhole forms when the roof of the cave collapsesA sinkhole forms when the roof of the cave collapsesA sinkhole forms when the roof of the cave collapsesA sinkhole forms when the roof of the cave collapses
Atlantic Coastal Atlantic Coastal Plain Arches and Plain Arches and
EmbaymentsEmbayments
The eastern margin of The eastern margin of North America has North America has been folded into a been folded into a series of NW-SE-series of NW-SE-trending arches and trending arches and embayments by embayments by tectonism associated tectonism associated with formation of the with formation of the Caribbean plate and Caribbean plate and persistent northward persistent northward movement of Cubamovement of Cuba
Fall ZoneFall Zone
Carolina Bays near Carolina Bays near Orangeburg, SCOrangeburg, SC
Carolina Bays are NW-trending oval depressions Carolina Bays are NW-trending oval depressions surrounded by a sand rim. They are found only on the surrounded by a sand rim. They are found only on the Middle and Lower Coastal Atlantic Plain Middle and Lower Coastal Atlantic Plain
The Western Margin of North AmericaThe Western Margin of North America
Continued subduction of the Continued subduction of the Farallon PlateFarallon Plate yielded yielded the:the:• Juan de Fuca and Cocos platesJuan de Fuca and Cocos plates (its Cenozoic (its Cenozoic remnants)remnants)• San Andreas fault systemSan Andreas fault system• Numerous Cordilleran accreted terranes Numerous Cordilleran accreted terranes
Accreted Accreted CordilleranCordilleran
Volcanic Volcanic Island Arc Island Arc TerranesTerranes
An eastward-advancing wave of hot mantle An eastward-advancing wave of hot mantle caused...caused...
Cretaceous-TertiaryCretaceous-TertiaryLaramide uplift Laramide uplift
of Archean crust of Archean crust that formed the that formed the Rocky MountainsRocky Mountains
Uplift of the Uplift of the Colorado PlateauColorado Plateau
Wind River Range,Wind River Range,a Laramide uplift a Laramide uplift
Extension that Extension that formed the formed the
Basin and RangeBasin and Range
E-dipping Permian (left), Triassic (red) and Jurassic E-dipping Permian (left), Triassic (red) and Jurassic (tan) sandstone beds (right) on the E Flank of the Wind (tan) sandstone beds (right) on the E Flank of the Wind
River Range (a Laramide Archean basement uplift). River Range (a Laramide Archean basement uplift). View toward the NW from Red Canyon Overlook near View toward the NW from Red Canyon Overlook near
Lander, WyomingLander, Wyoming
Oregon Oregon TrailTrail
Centers of Centers of Cenozoic Cenozoic
CordilleranCordilleran VolcanismVolcanism
Yellowstone Yellowstone hot spothot spot
Columbia plateauColumbia plateauflood basalts flood basalts
San JuanSan Juanvolcanic volcanic
fieldfield
CascadeCascadeRangeRange
ArizonaArizonavolcanic volcanic
fieldfield
Snake River Snake River PlainPlain
Columbia Plateau, Snake River Plain, and Columbia Plateau, Snake River Plain, and Yellowstone: Products of the Yellowstone Yellowstone: Products of the Yellowstone
Mantle Plume Hot SpotMantle Plume Hot Spot
Columbia River PlateauColumbia River Plateau
Northwestward movement of N. A. over the hot spot in Northwestward movement of N. A. over the hot spot in the Mid Tertiary caused eruption of the Columbia the Mid Tertiary caused eruption of the Columbia Plateau flood basalts. Then N. A. began moving toward Plateau flood basalts. Then N. A. began moving toward the SW, forming the hook-like shape of the Snake River the SW, forming the hook-like shape of the Snake River Plain flood basalts Plain flood basalts
Island Park CalderaErupted the Huckleberry
Ridge tuff 2 Ma
Henry’s Fork CalderaErupted the Mesa Falls
tuff 1.3 Ma Yellowstone CalderaErupted the Lava Creek
tuff 0.6 Ma
YellowstoYellowstonene
Calderas Calderas
Comparison of Volumes of Pyroclastic Comparison of Volumes of Pyroclastic EruptionsEruptions
Subduction of the Juan de Fuca plate along the Subduction of the Juan de Fuca plate along the Cascadia subduction zone is responsible for the Late Cascadia subduction zone is responsible for the Late Tertiary to recent volcanism of the Cascade Range Tertiary to recent volcanism of the Cascade Range volcanoes volcanoes
Cenozoic Cenozoic Volcanism Volcanism
in the in the Cascade Cascade
RangeRange
San Francisco Mountains, ArizonaSan Francisco Mountains, Arizona
Late Cenozoic volcanism formed the San Francisco Late Cenozoic volcanism formed the San Francisco MountainsMountains
Volcanism ceased ~ 1200 years agoVolcanism ceased ~ 1200 years ago
They are remnants of a stratovolcano that blew its topThey are remnants of a stratovolcano that blew its top
The The Circum-PacificCircum-Pacific and and Alpine-Himalayan Alpine-Himalayan orogenic orogenic belts, Earth’s present-day major mountain building belts, Earth’s present-day major mountain building beltsbelts
Earth’s Major Orogenic BeltsEarth’s Major Orogenic Belts
• Volcanism, seismicity, and deformation in the Alpine-Volcanism, seismicity, and deformation in the Alpine-Himalayan orogenic belt extends eastward from Himalayan orogenic belt extends eastward from Spain through the Mediterranean region into Spain through the Mediterranean region into Southeast AsiaSoutheast Asia
• The tectonism, due to The tectonism, due to collision of the Arabian, African and Indo-Australian plates with the Eurasian plate, ,
The Alpine-Himalayan Orogenic BeltThe Alpine-Himalayan Orogenic Belt
Eocene (50–40 MaEocene (50–40 Ma
Miocene (25–15 MaMiocene (25–15 Ma
caused closure of the Tethys sea
caused closure of the Tethys sea
• Is occurring in response to northward movement of the Is occurring in response to northward movement of the African and Arabian plates toward southern Europe African and Arabian plates toward southern Europe
• The convergence is causing deformation along a linear The convergence is causing deformation along a linear zone from Spain eastward through Greece and Turkey zone from Spain eastward through Greece and Turkey and along Africa's northwest coastand along Africa's northwest coast
The Alpine OrogenyThe Alpine Orogeny
Products of the Alpine Orogeny Products of the Alpine Orogeny • AlpsAlps (France, Germany, (France, Germany, Switzerland)Switzerland)• PyreneesPyrenees (Spain and France) (Spain and France)• ApenninesApennines (Italy) (Italy)
The Alps in The Alps in Southern GermanySouthern Germany
• Subduction of Mediterranean crust under Italy, Subduction of Mediterranean crust under Italy, Greece, and Turkey continues to cause volcanism and Greece, and Turkey continues to cause volcanism and seismicityseismicity
• In 1999 an earthquake killed 17,000 people in TurkeyIn 1999 an earthquake killed 17,000 people in Turkey
Italy and GreeceItaly and Greece
Mount VesuviusMount Vesuvius, Italy, has erupted , Italy, has erupted 80 times since it destroyed Pompeii80 times since it destroyed Pompeii
in A.D. 79in A.D. 79
Mount EtnaMount Etna, Sicily, is , Sicily, is Earth’s most active volcanoEarth’s most active volcano
The Mediterranean BasinThe Mediterranean Basin
Most of the water flows into the Mediterranean Sea from Most of the water flows into the Mediterranean Sea from the Atlantic Ocean through the Strait of Gibraltarthe Atlantic Ocean through the Strait of Gibraltar
Northward advance of the African plate ~ 6 Ma closed Northward advance of the African plate ~ 6 Ma closed the Strait of Gibraltar, caused the Sea to dry upthe Strait of Gibraltar, caused the Sea to dry up
When the dam broke, a colossal flood from the Atlantic When the dam broke, a colossal flood from the Atlantic ocean rushed into the basin and re-filled the seaocean rushed into the basin and re-filled the sea
• Subduction of the Cocos plate under western Central Subduction of the Cocos plate under western Central America is causing mountain-building and volcanismAmerica is causing mountain-building and volcanism
• Subduction of the Nazca plate under western South Subduction of the Nazca plate under western South America is causing mountain-building and volcanismAmerica is causing mountain-building and volcanism
• Subduction of the Pacific plate under western Asia is Subduction of the Pacific plate under western Asia is causing mountain-building and volcanism in Japan causing mountain-building and volcanism in Japan and the Philippians and the Philippians
The Circum-Pacific Orogenic BeltThe Circum-Pacific Orogenic Belt
Global Cooling and Warming Since the Global Cooling and Warming Since the ArcheanArchean
Paleogeography Paleogeography during the during the
Permian Ice AgePermian Ice Age
Global Cooling and Warming Since the Global Cooling and Warming Since the CretaceousCretaceous
Changes in Changes in Sea Surface Sea Surface TemperaturTemperatur
es Since es Since the Eocene the Eocene
HighHigh
The Pleistocene “Ice Age”
The Pleistocene “Ice Age”
Pleistocene Ice Ages and Interglacial Pleistocene Ice Ages and Interglacial IntervalsIntervals
• The Pleistocene began 1.6 Ma, ended 10,000 years agoThe Pleistocene began 1.6 Ma, ended 10,000 years ago
• Four major periods of widespread glaciation occurred, Four major periods of widespread glaciation occurred, were separated by warmer interglacial periodswere separated by warmer interglacial periods
Two Notable Pleistocene Terminal Moraines
End morainesEnd moraines
Long IslandLong Island
Cape CodCape Cod
Glacial and Glacial and Pluvial LakesPluvial Lakes
Pluvial Lake Pluvial Lake BonnevilleBonneville
Glacial Lake Glacial Lake MissoulaMissoula
Wave-cut shore lines cut Wave-cut shore lines cut by Glacial Lake Missoulaby Glacial Lake Missoula
Channeled Scablands formed Channeled Scablands formed by the Missoula floodby the Missoula flood
Great Salt Great Salt LakeLake
Pleistocene Glaciation of the Northern Pleistocene Glaciation of the Northern HemisphereHemisphere
Climate BeltsMaximum Extent of glaciation Maximum Extent of glaciation
in the Northern Hemispherein the Northern Hemisphere
Sea Level Change during the Past 20,000 Sea Level Change during the Past 20,000 YearsYears
Global warming has been Global warming has been occurring for 17,000 yearsoccurring for 17,000 years
Positions of the coastline of North America during the Ice Age and if the ice
sheets melt
What is thought to...What is thought to...
...have caused the Pleistocene Ice Age?...have caused the Pleistocene Ice Age?• Formation of Central America deflected the Gulf Formation of Central America deflected the Gulf
Stream and moist air northward, produce more snowStream and moist air northward, produce more snow• Northward movement of North America and Eurasia Northward movement of North America and Eurasia
provided more surface for snow accumulationprovided more surface for snow accumulation
...also cause/contribute to occurrence of ice ...also cause/contribute to occurrence of ice ages?ages?
• Milankovitch cycles, natural periodic changes inMilankovitch cycles, natural periodic changes in• Earth’s orbital eccentricityEarth’s orbital eccentricity • Tilt of Earth’s axisTilt of Earth’s axis • Precession of Earth’s axis, of the equinoxesPrecession of Earth’s axis, of the equinoxes
– Cause periodic changes in the amount of sunlight Cause periodic changes in the amount of sunlight at high latitudesat high latitudes
– Lead to natural periods of global cooling and Lead to natural periods of global cooling and warmingwarming
• Excessive volcanism, etc.Excessive volcanism, etc.
Milankovitch CyclesMilankovitch CyclesA change in Earth’s orbital eccentricity A change in Earth’s orbital eccentricity occurs every 100,000 yearsoccurs every 100,000 years
A 2° change in tilt of Earth’s A 2° change in tilt of Earth’s axis occurs every 41,000 yearsaxis occurs every 41,000 years
A precession of Earth’s A precession of Earth’s
axis occurs every axis occurs every
23,000 years23,000 years