marble canyon
"The earth is the geologist's vast puzzle box."

suggested Louis Agassiz.

The "Earth is quite a charmed planet. . . . Earth as a cradle of life can be seen in its prehistory, its origins, its chemical composition, and its early evolution. . . . Earth is actually the final product of an elaborate sequence of events that occurred over the span of 15 billion years, three times the age of the Earth itself. . . . a formidable task."

Peter D. Ward & Donald Brownlee, Rare Earth, p. 36-37.

  These Grand Canyon walls record the hidden history; what the displays at the American Museum of Natural History, or the Oxford University Museum of Natural History, or Yale University's Peabody Museum interpret for all of us who sojourn on earth for but a brief duration.

The fossils from the walls of the Grand Canyon account for rock formations that are between 2 billion and 600 million years old. They reveal frequent examples of adaptive radiation of life from the sea, to the air, and onto dry land. Large sections of the fossil record are missing from the canyon's rock walls. These limestone walls suggest the importance of the ocean in fostering life on earth; the fossils found in these canyon rocks reveal a startling puzzle. These pieces of the geological puzzle that we see are from distinctly different ages of the land, because strikingly divergent body plans found in these fossils indicate numerous successive changes in the terrains over the long-term, or deep geological past. The Colorado River has cut down through the planet's history to reveal numberless lost world's of fantastic variety.



Comparative measures of time in Earth history.

The great divisions in the "rocks of ages" record both subtle and enormous changes based on the shifting dominance of marine, to vegetable, and eventually terrestrial fossils.

These geological divisions in the fossil records in sequence of occurrence are: Hadean, Archean, Proterozoic, Paleozoic, the Mesozoic, geologic timeand the Cenozoic eras interspersed by mass extinctions hidden deeply in the geological past.

Geological time 650 million to 200 million years


The deep past from which life descended into today's biological variety called biodiversity.


Our present time. arrow


Along the right there is a listing of the most recent to the oldest or earliest periods from fossil evidence drawn with respect to the relative temperatures that are revealed by that fossil data, during those vast periods of geological time.



The starred lines ( ******* # ******* ) below refer to five of the many world-wide, mass extinctions or times during which there occurred a planetary collapse of ecosystems.

********1** These prolonged extinction events shaped the kinds of dominant species and their descendants on Earth in subsequent periods such that surviving groups of creatures could adaptively radiate throughout the world in particulalrly sustaining conditions favorable to their needs.



The species we see today –contributing to the biological diversity, biogeography, and ecological puzzle pieces– are experiencing another worldwide extinction; in part induced by the spread of human settlements, agriculture & industry.




variability of surface and ocean temperatures in the deep past is revealed in the graph. The right side of the graph indicates colder prevailing temperatures while the left side shows warmer periods. This long stability of the warm period in the Cambrian when so many varied body forms of both radially and bilaterally symmetrical organisms are discoverable in the fossil record are examples of how widespread the diversity of life had become during the what is called a "Cambrian explosion."

******* For periodic extinctions, see: one, two, three, four, five, six.

Orogeny: For a detailed look at North American mountain building episodes see the site–

Biogeny: For a detailed look see University of California Berkeley Museum of Paleontology: history of life.


The Geological Record

compiled by Joseph Siry


YEARS, Before the Present: BP           ------------           SEAS           -------- CLIMATE --------           WILDERNESS

25--20 billion,

13.7 billion,    
The origins of the universe and the simplest atoms:
H & HE
tritium hydrogenhelium
    solar system
5 billion,

origins of the Solar System

astral prime
Eons, Eras, & Periods, are shown in bold; mountain building called an orogeny in brown.

******* Earth's episodic extinctions: one, two, three, four, five, six. *******

earth HADEAN

4.6 – 3.8 billion, gradual formation of the planet Earth from space debris and interstellar gas.

4.3 billion, The Earth's surface cooled as scattered ponds coalesced into larger water bodies from either outgassing of water from volcanoes or the interception of icy meteorites striking the molten iron-rich surface.


3.96 billion, oldest known rocks on Earth 3.8 billion,

3.5 billion "abundant organisms capable of responding to light and able to build mounds existed . . .in rocks from the Warrawoona region of Australia."

Rare Earth: Why Complex Life is Uncommon in the Universe. p. 66.

3.2 billion, further evidence for an origin of life in the form of bacterial lines of life that feed off of volcanic sulfur and surface methane.

√ – proto-cells fossilized that are PROCARYOTIC MONERAN CELLS having spread in extensive oceans.

3 billion

Nsuze Palesol the name of an archaic soil from Africa; "three-billion-year-old soils from South Africa shows that oxygen appeared in the atmosphere more than 600 million years earlier than previously thought, . . ."

graph Rising oxygen levels were an inadvertently beneficial outcome of bacterial activity.


3 billion, Literally: older plants; figuratively called the dawning of the earliest plants.


2.5 billion, Cyanobacteria are dominant reef builders form oldest Canadian Shield rocks of the SLAVE PROVINCE

2.4 billion, Rift valley forms in the Slave and Bear provinces

2.3 billion, Stromatolite Reefs form of blue-green bacterial layered colonies having formed mats in shallow coastal seas.

2.2 billion, Oldest glacial evidence for an early ice-age.

2.1 billion, Slave / Bear continent rests over mantle plumes, creating volcanic activity.

2.1 – 1.8 billion,

WOPMAY OROGENY (mountain building) tears the Bear and Slave continent apart opening a 2,500 kilometer wide ocean basin due to continental drift.

2 billion,

Some oxygen in the atmosphere and BLUE GREEN BACTERIAL reefs flourish in the Great Slave Lake.

1.9 billion, 1.8 billion, 1.7 billion,

1 billion,


1,0000 million-700 million years ago Rodinia a supercontinent existed.

√ – the supercontinent of Rodinia made up of US and Canada with Euro-Africa-Asia around it created a huge desert. Little to no water was readily available meaning extensive arid conditions spread.

An earlier supercontinent –persisted for 350 million years– has been given the name Rodinia,;"a Russian word meaning 'homeland,' formed from a mass continental collision blocked the warm water currents that flowed previously to the poles and a prolonged ice age began, ice advanced and covered the earth, plunging temperatures to – 40? {minus 40 degrees F} and affecting most if not all species of living creatures. During this period when so many land-masses congealed cyanobacteria dominated the planet's oceans, ultraviolet radiation permeated the air, and there was no evidence of life on land."

Rocks of the Okanogan Highlands are nearly a billion years old,"Geologists have named these rocks the “Belt Supergroup” after a small town in Montana. The Belt rocks are multicolored sandstone, siltstone and limestone noted for their beautiful preservation of sedimentary features such as mud cracks, ripple marks and abundant 'stromatolites' –cabbage shaped fossils left by the action of cyanobacteria.”

Burke Museum of Natural History

plates" . . . some 750 million years ago, the end of Rodinia began in what is now east-central Washington.

There exists substantial & convincing "evidence that ice extended to near equatorial latitudes in the late Precambrian, about 700 million years ago. . . . all of the oceans may have been covered with ice to considerable depths . . . . These extremely cold temperatures would have had an enormous influence on the surface of our planet. For example, continental weathering would have slowed or stopped . . . . From space Earth would have looked white and brown–the white being the ice covers on the oceans, the brown the denuded land areas. . . . The oceans would have begun to accumulate with metal ions, mainly iron and manganese. For as long as 30 million years, the glaciers and ice never relaxed their frigid grip . . ."

Rare Earth: Why Complex Life is Uncommon in the Universe. pp. 114-116.

680 million,

free oxygen at 1% of the current ambient level in the atmosphere, due to the photosynthesis ability of blue-green bacteria.

680 -until- 230 million,

Ediacarianoxygen accumulates from 3% to 10% of the current ambient level in the atmosphere, Ediacaran limestone laid down in a shallow, warm seas.

Such marine seas are where calcium in the water reacts with carbon to form a milky dispersion called calcium carbonate which is heavy enough to settle at the bottom of a watery pool if the winds do not stir up the bottom sediments and the pH is such that calcium carbonate hardens and settles on the quiet sea bottom.

680 million years old,


670 million, jellyfish fossil, blue-green bacterial reef forming organisms flourish in warm shallow seas, called stromatolites.

About 650 million years ago, seventy percent of the dominant Precambrian flora and fauna perished in the first great extinction.


600 million,

Ural Mountains rise from the collision of Europe with Siberia,TRILOBITES numerous;

Trilobite types

From the Oxford University natural history museum an example of the variety of trilobites from the Precambrian seas of the Panthalassic ocean.

    FLORIDA an island arc of volcanoes.

570 million,

IAPETUS SEA, or Proto-Atlantic Ocean, begins to shrink.

    AVALONIAN OROGENY occurred where a terrain collides with North America in the region of BOSTON and New England. Avalonian orogeny
    Ediacaran fossil

    A filter feeding animal from the Precambrian seas.


    Charniodiscus arboreus specimen is from Australian fossil bearing rocks of an upper level filter feeder from the benthic zone of Precambrian seas.
    Oxford University Museum of Natural History. Siry, July 2006.  

550 million, chitin shelled creatures emerge (same exoskeleton as insects).

AVALONIAN OROGENY ends in the creation of a micro-continent;

It as called Avalonia (right) as a series of terrains (an island arc) that form the rocks Avalonianow found in the mountains of Great Britain, Newfoundland, Canada and eastern New York state and New England, suggesting that these now separate mountain chains were once a single chain like the Andes.

"Rhode Island and the New England states were not the only land masses to emerge from the Avalonian arc. In the sketch above, J marks the approximate location of Jamestown, Rhode Island. EW indicates the portion of Avalonia that became southern Ireland, England and Wales, Ib shows Iberia (Spain and Portugal) and Ar Armorica and Bohemia. A portion of the arc is now part of Morocco. Future parts of Nova Scotia, New Brunswick and Newfoundland, as well as most of New England are offshore from Florida (labeled F on the map at right). The portion of the arc that became part of the Carolinas is to the right of Jamestown, offshore of what is now Venezuela, in South America."

Paleozoic Era

An explosion (Cambrian seas) of water plants and marine animals. In terms of the variety of ancestral populations we still can identify living now. Below is a diagram of taxonomic groups still extant today from this earlier archaic period and found in the fossil records.


545 million, – extensive oceans cover North America ( N. A. is red on the map to the right.) warm shallow seas persist worldwide.

An explosion of shallow marine organisms with greater varieties of body plans (invertebrates) than are now living or currently extant.

540 million, lampreys as one mere example of a representative animal family of "all of the animal phyla (the categories of animal life characterized by unique body plans, such as arthropods, mollusks, and chordates)" which "either evolved or first appear in the fossil record. . . . animals are both diverse and abundant in 500 million year-old rocks, and they include representatives of most animal phyla still found on Earth. . . . The rate of evolutionary innovation and new species formation during the Cambrian Explosion has never been equalled."

Rare Earth: Why Complex Life is Uncommon in the Universe. pp. 125-126.

Marine arthropod called Anomalocaris (at left and below from Burgess shale fossils) is a seaside predator of some immense size and speculated ferocity. It fed in waters where salt water algae, sponges, brachiopods, cnidarians, mollusks, trilobites, crustaceans, starfish, and stromatolite reef building species spread in the warm tropical seas.

This predator was a large creature feeding on bottom dwelling denizens, or animals classified by where they live and are called called benthic fauna. Anomalocaris was a free swimming animal, unlike the corals and anemones.

A far greater diversity of animal body forms existed in this period, than now, since the evidence in the Burgess shale (Canada) formations is extensive:

 530 m. y. a. –– The BURGESS SHALE FORMATION: 

"By recognizing so many unique anatomies in the Burgess, and by showing that familiar groups were then experimenting with designs so far beyond the modern range, they have inverted the" way we think about the diversity of life on earth. "The sweep of anatomical variety reached a maximum right after the initial diversification of multi-cellular animal. The later history of life proceeded by elimination, not expansion. The current earth may hold more species than ever before, but most are iterations on a few basic body plans."

"Compared with the Burgess seas, today's oceans contain many more species based upon many fewer anatomical plans."

"The maximum range of anatomical possibilities arises with the first rush of diversification. Later history is a tale of restriction, as most of the early experiments succumb and life settles down to generating endless variants upon a few surviving models. "

Stephen J. Gould, Wonderful Life, p. 47.  

Animals fossils found in the Burgess shale formation [above right] reveal the most diverse array of body plans ever found.

520 million, Avalonian continent is finally broken up.

510 million, Closing of the ancient Iapetus Sea (the prototype of the later – Atlantic Ocean)

extensive & massive extinctions of sea-life due to a worldwide ecological collapse.

*********************************** 1: Cambrian Extinction ********************************


Well over half of North America covered by ocean water. There exists "evidence of continental glaciation at the Cambrian-Ordovician boundary is responsible for a decrease in global climatic conditions. Such a decline in temperature is implied by Miller" to have destroyed the existing "Cambrian fauna which are intolerant of cooler conditions, producing a mass extinction of mostly warm water species." This cooling led to oxygen depletion of the waters and a mass mortality of marine creatures

505 million, early shelled (calcium carbonate) organisms such as Anomalocaris and fishes.

500 million, early mountain building (Orogeny) in Eastern N. A.

Cephalopods like the chambered nautilus' ancestors called ammonites are varied and dominant. The earliest vertebrates are extensively preserved in limestone dominant rock (slate and marble sources). Huge deposits of once living creatures form oil and gas deposits associated with the rocks of the Cincinnati Arch; Tapeats Sandstone and Bright Angel formations of Grand Canyon.


Appearance of the first land arthropods and land plants.

438 million,

early vascular plants, ancestral mosses and liverworts. The club-mosses' ancestors' called LYCOPSIDS emerged as the largest land forested genera expanding in the Carboniferous forests–the source of modern coal.

See Lycopsids in the Dictionary of Botany


408 million,

Coelacanths and other jaw less fishes emerged, the earliest evergreen forests began to dominate the land. In these seas there were sharks and "A Devonian tetrapod-like fish..." from the middle Devonian 375 million years ago marking the slow transition to land of these sea-dwellers.

"The first trees on earth. Its name was Archeopteris, and along rivers it grew sixty feet high, a tall conifer shaft with these fronds hanging from its branches, overshadowing the life below. . . . the fruiting bodies of the Archeopteris and leaves . . . scattered among the Archeopteris were minnow-sized fishes, irredescent lung-fishes teeth, scales of armored, placoderm fish." A.

The planet's land masses were divided into Gondwanaland in the south and Laurasia in the north divided by the shallow circum-equatorial water body called the proto-Thethys Sea.

Life in the Devonian sea was quite diverse including giant eurypterids or 'sea scorpions' pursued early devonianjawed fishes, including acanthodians (sometimes called 'spiny sharks', though not related to true sharks) and shield-headed fishes called placoderms (which probably shared a common ancestor with the sharks).

Rugose and other corals built great reefs, providing food and living spaces for many different kinds of creature.

The sea floor supported a rich variety of crinoid 'sea lilies', stalked clam-like animals called brachiopods, bizarre colonial critters known as graptolites, and early versions of mollusks - such as chitons, tusk shells, and straight-shelled cephalopods related to modern-day nautiloids.

The first plants - small, leafy pioneers known as reunifies - colonized the land, followed shortly thereafter by joint-limbed creatures such as scorpions, centipedes, and millipedes.


400 million years ago:

    fishes dominate seas; early amphibians spread; vascular plants: club mosses, horsetails, Gymnosperms, seed ferns and other green plants are common.

375 million,

    Mangrove swamps, fish on mud flats, ACADIAN OROGENY formation of a Appalachian/ Pennine/ Scandinavian single mountain chain stretching along the equator.

    The tetrapod called Tiktaalik–a fossil of a predatory "four-footed" fish with the head of a crocodile revealing the sort of link between land dwelling animals and their fish cousins. "Tiktaalik lived,..." on "a landmass that straddled the equator and had a subtropical climate." See the Fish-tetrapod transition, NSF. "a remarkable new fossil species that represents the most compelling evidence yet of an intermediate stage between fish and early limbed animals."

    "The skeletal structure of Tiktaalik and the nature of the deposits where it was found suggest an animal that lived on the water bottom, in the shallows, and perhaps even out of the water for short periods.

    "The skeleton of Tiktaalik indicates that it could support its body under the force of gravity whether in very shallow water or on land," said Farish Jenkins of Harvard University. "This represents a critical early phase in the evolution of all limbed animals, including us."

    Quoted in the National Science Foundation press-release.

Global climatic changes lead eventually to Devonian catastrophe a "great period of extinctions."

**************************************** 2: Devonian extinction **********************************


The tropical warmth fostered huge forests defining this coal forming age persisted due to extensive swamps and favorably wet climate conditions over Eurasia and North America.


Artist's rendering of the carboniferous forest based on fossil evidence.

Lycopsids: "These trees dominated the lowland swamps of the Upper Carboniferous and contributed most of the organic matter to the vast coal deposits that extend over much of North America and Eurasia." See "The Devonian Times" and especially the Lycopsid pages.

A number of Carboniferous arachnids somewhat resembled spiders, and in fact appeared at about the same time as the first true spiders. Like spiders, they were terrestrial and respired through book lungs, and walked on eight legs. However, they were not true spiders, nor necessarily ancestral to them, but represented independent offshoots of the Arachnida. Trigonotarbids are currently the oldest known land arthropods.

Most of these fossils of the oldest known land arthropods are found in the Upper Carboniferous (Pennsylvanian), though they have also been found in the Ludlow Lane fauna of England (Pridolian, late Silurian), the Alken an der Mosel fauna of Germany (Emsian, early Devonian) the Rhynie Chert of Scotland (Siegenian, early Devonian) and the Gilboa, New York fauna from the Panther Mountain formation (Givetian, middle Devonian). Not much is known about their relationships. [See: U. C. Berkeley, Museum of Paleontology].


380 million, Antler Orogeny was the "first major tectonic event to affect the passive margin that transected" horseshoe crabNortheastern Nevada and Western Utah.

"The Antler orogeny occurred in Mississippian time at a passive margin of the sialic North American continent in Nevada and probably in Idaho." see: Speed and Sleep "Antler orogeny and foreland basin..." in Geological –GSA:Bulletin– Society of America.


360 million, modern ancestors of the "naked seed" plants we call Gymnosperms; cycads, conifers and gingkos are widely evident in the fossils.

These plants were food for the earliest amphibians and reptiles that emerged in vast warm, moist (tropical) swamps.

Huge horsetails (equisetum, a descendent pictured at left) coexist with giant dragon flies tree-like progymnosperms such as the Archaeopteris and lycopsids.

Horseshoe crab ancestors – relatives of spiders and scorpions – are increasingly numerous in the fossil record and they possess blue or copper bearing (not iron as in hemoglobin) blood.

345 million, large amounts of vegetation that have become fossilized leading to coal formations worldwide.

Oceans increase in volume worldwide.

325 million,plates

GONDWANALAND (a vast southern continent made of Africa, South America, Antarctic, Australia and India) separates from Euro-Asian-N. American continent.

Pennsylvanian Sea invades Southwestern North America creating warm tropical seas beside extensive swamp and flood lands.


320 million, beetles and dragon flies thrive in luxuriant swamps, tropical inland seas. treesNevada is an ocean bed.


300 million, Tree ferns and lush forests dominated by the scale tree or Lepidodendron characterize widespread swamps that formed the basis of today's coal deposits in America, Europe, South Africa and Russia.


Southern APPALACHIAN MOUNTAINS formed from collision with AFRICA;



286 million,

Appalachian Mountains attain the
size of today's Rocky Mountains or European Alps
as the super continent Pangaea or Pangea formed, vast wind-blown deserts cover north America and Dimetrodon dinosaurs spread.

Ice sheets form in the southern portions of Pangean super continent.

240 million years ago crocodiles & alligators separated from dinosaurs .

245 million, Permian Extinction: half of the known families of animals and plants, both terrestrial and marine, perished!

"Some 252 million years ago, the Permian-Triassic mass extinction wiped out an estimated nine of every ten species on the planet—scientists call this one “the Great Dying.”

Scientific American, Lee Billings, "Fact or Fiction?: Dark Matter Killed the Dinosaurs
A new out-of-this-world theory links mass extinctions with exotic astrophysics and galactic architecture," March 25, 2015

********************************* 3: Permian Extinction ****************************************

Mesozoic Era

ae Triassic


235 million, renewed warming allows stromatolites, coralline algae & bryozoans begin to form reef communities after a long,10 million year hiatus.

Emiliania huxleyi played an expanding role in Earth's climate through both coccolith formation and gas emission. Crocodiles and alligators survived the Permian Extinction.

The late Triassic world as revealed in the Palisades Orogeny was characterized by the start of the break-up of a great continent of Pangaea, straddling the equator, depicted on this map of the globe at that time. Globe of the later Triassic showing locations of the oceans and Pangaea.

This is the period in which the ancestors of today's turtles & tortoises arose taking advantage of the warm waters and warm seas of the great Panthallasic Ocean and the Tethys Ocean stretching under the Earth's equatorial sun.

214 million years ago the Manicouagan impact crater formed [65 kilometers (40 miles) in diameter] in what is now Quebec, Canada.

Jurassic, slow opening of the Atlantic Ocean due to sea floor spreading.

The 100-kilometer-wide Manicougan Crater in Canada was produced by a 5-kilometer-wide space rock smacking into Earth about 215 million years ago.

208 million, early flowering plants or angiosperms appear.

Archaeopteryx fossils of a flying reptilian bird thought to be a clue to the remarkable divergence of birds from reptiles and dinosaurs.

The silica based diatoms spread throughout the warm seas after the mass extinction.


144 million, the end of a reptilian age of Dinosaurs and Pterosaurs.

platesA very extensive equatorial shallow ocean called Tethys Sea forms connecting the Atlantic, Pacific and Indian ocean basins leaving only 18% of the Earth as dry land, as a circum-equatorial and hence warm water system redistributing heat around the planet.

Spread of gymnosperms & angiosperms.

During the Cretaceous "Florida was a shallow submarine limestone bank."

according to Professor Robert A. Gastaldo,

132-130 million, The Brandberg Massif or Brandberg Intrusion in central Namibia: a granitic intrusion forms a dome-shaped massif today, originated during Early Cretaceous rifting that led to the opening of the South Atlantic ocean.

120 million, unfadingly hot climate prevails.

100 million, placental mammals appear and as birds spread worldwide.

77 million, an abandoned nest of egg-laying therapod–a small meat-eating dinosaur–from Alberta.

75 million, fossil from Alberta sands a complete nest of turtle eggs recovered. First "fossil of a pregnant turtle found" of a species of river turtle called Adocus. See *

66.4 million, Cretaceous extinction of once very widespread and diverse dinosaurs, trilobites, and ammonites is the largest mass die-off in terms of diverse forms of life since the Permian time.

********************************** 4: Cretaceous extinction ***********************************

Cenozoic Era

Modern period of animals indicative of large predators and herds of herbivores on the prairies of Eurasia, including India, Africa and the South American Pampas, the North American Great Plains are slowly drying creating arid grasslands.



65 million, the long collision of India with Eurasia begins.

Himalayan Orogeny or mountain uplift starts and by 30 million years ago closes the Tethys Sea. The mass and height of the mountains inaugurates a change in the climate triggering as many as twenty ice ages between 2 million and 10,000 years ago.

The horse descent illustration below is from recent to oldest at the bottom:

horses Eocene

57.8 million, early primates, giant birds, formation of grasslands in Eurasia, Africa and the Americas due to mountain building,

The Hyracotherium or early horses, so called "eohippus," in the fossil record.

50 million, earliest Sirenians in the circum-global, Tethys Sea.

40 million, extinction of "part of a very large group of species called the baenid turtles," due it is thought to the drying out or desertification of North America. The group was river dwelling consuming soft, aquatic plants and crustaceans.

These turtles had ironically survived the Cretaceous extinction. For more see: Yale University-The great Tree of Life.



36.6 million, the San Andreas Fault system of California starts to gradually take shape in the middle Tertiary time (beginning about 28 million years ago). The gradual movement on the fault system since that time is about 282 miles stretching from the Gulf of California to Cape Mendocino and dividing the state into two opposite moving plates along a seismically active transform fault boundary.

The slow closing of the Tethys Sea that equatorially connected the world's oceans.


23.7 million, extensive marine intrusion in California, Florida, the Mississippi Valley, and Texas, called a marine transgression; monkey-like primates emerge.

Northern Australia reaches its present tropical position and the Great Barrier reef begins forming. A circum-equatorial sea girdles the earth creating a warmer dispersal of tropical waters to the poles and connecting the oceans along the equator.

15 million, the initiation of the San Andreas fault system, the plate tectonic setting of the western U.S. had until then been dominated by subduction toward the east of one or more oceanic plates beneath the continent, the Farallon plate prominent amongst these moving pieces of the Earth's surface.


San AndreasVolcanic rocks in the Hollister of Central California region are roughly 12 million years old.

Whereas the volcanic rocks in the Sonoma-Clear Lake region north of San Francisco Bay range from only few million to as little as 10,000 years old.

Both of these volcanic areas and older volcanic rocks in the north bay region are offset by the modern regional fault system that has been active since the formation of those rock assemblies.

(Image modified after original illustration by Irwin, 1990 and Stoffer, 2006.).

The convergence of these oceanic plates with the western edge of the North American plate profoundly influenced volcanic and igneous activity west of and including Colorado, and caused mountain building (orogenesis) in the same region.


When two plates converged (sutured) or come together; the remnants can still be seen in the far western US.


10 million, Aegyptopithecene Apes thrive in northern Africa.

divergence of apes (Chimpanzees, Orangutans, & Gorillas) and hominid lines.

Equatorial Africa is well forested with little of the savannah that exists today.

6 million, Orrorin tugenensis in Kenya's rift valley, earliest human ancestor.

Orrorin tugenensis, a.k.a. the "Original man" from Tugen Hills, Kenya evidence for bipedalism at 6 million years ago!

American Museum of Natural History

The molecularly derived date (DNA sequences) for human divergence from chimpanzees.



5.5 million, Ardipithecus ramidus kadabba, from the Middle Awash, Ethiopia .

5.3 million, Antarctica rafted to its current polar position generating conditions for glaciers and ice sheets to form augmenting planetary cooling and a lowering of sea levels worldwide.

4.4 million, Ardipithecus ramidus in east Africa ( "the root of humankind" - in the native Ethiopian language. ). Note by Dr. Dennis O'neil Palomar College: "Ardipithecus ramidus is currently the best candidate for being the immediate ancestors of the australopithecines."

4.2 - 3.9 million, Australopithecus anamensis from east Africa. "4.1 million years ago in what had been a woodland environment in the Awash Valley of Ethiopia." See: Dennis O'Neil,"Discovery of Early Hominins" (2010)

skulls"dawn of human ancestry" *

*caveat: "virtually all our theories about human origins were relatively unconstrained by fossil data." David Pilbeam

3.5 million, Australopithecus bahrelghazali ( in Chad, central Africa ).

3.5 million, Kenyanthropus platyops.

3.4 million, hominid fossils in eastern Africa

A. afarensis emerge as an "alleged" candidate for human ancestry from 4 to 3 million years ago (mya), East African.

Human family's history exhibit at The American Museum of Natural History

3.2 million, "Lucy" hominid skeletal remains.

3 million, the closing of the circum-equatorial sea by a rise of land along the Isthmus of Panama, further elevation of the Himalayan plateau, and growth of permanent ice sheets in Antarctica.

genus Homo coexistent with Australopithecus, East Africa.

3 to 2 million, begins a million year survival of South Africa's A. africanus.

lucy2.5 million, Australopithecus garhi - was recovered between 1996 and 1998 from the Middle Awash, Ethiopia, evidence of lithic, or stone culture and of food processing (two characteristics normally attributed to the genus Homo).

Late Pliocene

2 million,

ice ageA series of Ice Ages and interglacial retreats commences. As ice accumulates the sea level declines; as glaciers melt during inter-glacial warming periods, the sea level rises. Consequent changes in the rainfall and temperature patterns triggered the retreat of extensive tropical forests in favor of more open grassland-savannah terrains where arid adjusted plants thrived.

Prehistoric sea level varies from 400 feet lower to 50 feet higher than today.

A widespread extinction at the end of the last glacial period occurred for those cold-adjusted species such as mammoths, mastodons, and giant sloths.


The human dawn of cultural variation

1.6 million The Solo River's site of Ngandong fossils reveal the arrival on Java, Indonesia of Homo erectus, where populations "apparently lived in 'splendid isolation' without competition from any other human species."

There is disagreement on the exact age of these Ngandong fossil-bed remains, much later Middle Pleistocene.

see: PLOS 1 (June 29, 2011) Article
Nature News, 28 July 2010 | Nature | doi:10.1038/news.2010.377

1–1.5 million Homo erectus —one human ancestor— evidence for these people as earliest "fire-users."

1 million year old remains of human fossils near Zhoukoudian, China (northern plain)

Sequences of Ice Ages persist with intermittent interglacial warming periods. Evidence of humans in Spain from eight fossil specimens among the oldest hominin from Europe ever recovered; Australian Museum.

Findings of a totally modern human facial morphology from "Gran Dolina (Sierra de Atapuerca, Spain)" Journal of Human Evolution, Pub/Med; 1999, Academic Press.

Homo erectus     500,000 Homo heidelbergensis believed to have migrated out of Africa into Europe.

     250,000 Homo neanderthalensis (persistent effects of Neanderthal DNA on modern human Eurasian populations: {Physics News; \ Science 12 Feb 2016.}) For age of Neanderthal populations in Asia and Europe 400,000 -28,000 years ago (Smithsonian).

     200,000 earliest modern human, or Homo sapiens, emerge in East Africa.

100,000 "modern humans began to spread out of Africa to begin the eventual colonization of the rest of the world." Bryan Sykes, Seven Daughters of Eve, p. 277.

              Homo erectus skull 

Mount Tobaa volcano at the northern part of the Indonesian island of Sumatra erupted 74,000 years ago among the largest volcanic eruptions in Earth's history.Cave paintings

     50,000 Neanderthal peoples in La Ferrassie, France

     36,000 – 25,000 Interglacial retreat of ice, cave paintings [shown at right] in Lascaux, France and Altamira, Spain (22,000 years ago).  


 20,000 Ice Age (Würm or Wisconsin) resumes with ice sheets in Britain and Scandinavia and equivalent ice in New England and the Great Lakes.

15,000 Interglacial Warming trend resumes, mountain glaciers retreat and sea level rises; sometimes abruptly rising sea-level erodes coastal sediments and drowns settlements.

Pleistocene extinction

loss of many large mammal species (mastodons, mammoths, giant ground sloth, saber tooth tigers, etc.).

********************************** 5: Pleistocene extinction ************************************


earth plates

10,000 Ice caps are shrinking causing sea levels to rise rapidly over 140 feet.

9,000 Pronounced warming of 3 to 5 degrees Celsius, worldwide.

8,000 domestication of cereal grains in the Mid-East, rice in south Asia.

7,000 Cities at Jericho, Israel and Catal Hüyuk, Anatolia. Rapid melting of glaciers (Deglaciation) causes sea levels to rise and the great drying-out of the extensive grasslands (desertification) for thousands of years begins.

6,000 "Homogecene" begins (term used to describe the homogenizing influence humans have on flora and fauna (biota) since the pursuit of agriculture created uniform crops and ornamental plants.


    Primary sites of plant and animal domestication in prehistory.

    Allegedly humans contribute to a warmer atmosphere as they adopt farming practices in eight to eleven areas around the world exposing populations to new diseases and a revolution in diet.

    The known areas were:

    • Mesopotamia
    • China, northern Yellow River and southern Yangtze River.
    • Thailand & Southeast Asia
    • New Guinea & Indonesia
    • India, Indus and Ganges Rivers
    • Mexico, lowland and highland
    • Peru the Andean slope and plateau
    • Eastern Brazil
    • Egypt, Lower and Upper
    • Ethiopia
    • Great Zimbabwe

30% of the Earth is dry land as extensive ice caps remain only in Greenland and Antarctica after the retreat of the Wisconsin or Würm ice age.


Found in the Ötzal Alps, the remains of a stone age man. Ötzi the ice man.


Recent prehistorical and historical events.

population trends

Greenland and Antarctic ice sheets are in a rapid phase of melting currently after the rise of carbon dioxide levels to over 400 parts per million in the atmosphere in a period of 200 years.

Visit the American Museum of Natural History, on line.


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By Joseph Siry

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Geologic time scale: University of California at Berkeley, Museum of Paleontology, U.C.

Peter D. Ward & Donald Brownlee, Rare Earth: Why Complex Life is Uncommon in the Universe. New York: Springer-Verlag, 2000.

A guide to mass extinctions: Hooper Virtual Paleontological Museum. Discussion of attributes of a mass die-off.

United States, National Aeronautics and Space Administration [NASA], Goddard Space Flight Center, Earth Sciences Division. Sea level

University of Calgary (2008, August 27). First Prehistoric Pregnant Turtle And Nest Of Eggs Discovered In Southern Alberta. Science Daily.

University of California Museum of Paleontology, [ Portal ]

University of Calgary (2008, November 14). Dinosaur Whodunit: Solving A 77-million-year-old Mystery. Science Daily. Retrieved July 23, 2011, from­ /releases/2008/11/081113181200.htm

Roy E. Hunt, "A brief Geological History of North America," table A.2. Geotechnical investigation methods: a field guide for geotechnical engineers. p. 327.

A. Zimmer, Carl. At the Water's Edge: Fish with fingers, Whales with Legs, and How Life Came Ashore but Then Went back to Sea. New York: Simon & Schuster, 1998. p. 42-43. Descriptions of the Devonian tetrapod environs of early North America.

Eon [aeon] is a length of geological time equal to a billion years, Eras are subdivisions of eons and Periods are subdivisions of eras; periods are further subdivided into epochs, while epochs are subdivided into ages. Pliocene Epoch of the Cenozoic Era.

Eventful Periods in
geological time



Hominins diverge from primates after
earliest primates emerged (Lemurids)


marine mammals return to the sea



oldest mammals


Amniotes diverge from Amphibians  



oldest vertebrates  

An older version of geologic time or "deep" time scale; chronological chart.


Coral provides clues to climate change

February 7, 2000

Web posted at: 11:43 AM EST (1643 GMT)

Like tree rings that reveal the age of centuries-old cedar, growth rings in Indian Ocean coral tell how El Niño, the warm-water phenomenon of the tropical Pacific Ocean, influences marine temperatures a continent away.

"We found a record of climate change that reflected the influence of the tropical Pacific (El Niño) on [the Indian Ocean]. This record tells us a story that has broad climate implications," said Julia Cole of the University of Arizona and co-author of a report on coral growth rings. "ENSO (El Niño/Southern Oscillation) has a very long reach. El Niño brings more rain to East Africa just as it does to Arizona, but it also warms the oceans there."

Reliable records of sea temperatures in the western Indian Ocean date back only a few decades, and scientists have been hard-pressed to decipher the long-term influence of El Niño on these temperatures. Coral rings are filling in the gaps.

"Climate data from this part of the world is limited," said Cole. "But coral can grow for centuries. We know that El Niño affects the inter-annual climate, which is the variability from year to year. El Niño also has a long-term cycle and we found that decadal variations of El Niño drive decadal variability in the Indian Ocean. People have never looked at the decadal variability and attributed it to the Pacific Ocean and El Niño."

Studying temperature records together with coral growth rings, the researchers discovered a correlation between El Niño in the tropical Pacific and higher surface temperatures in the Indian Ocean. El Niño, they conclude, has a greater effect than Asian and African monsoons on sea-surface temperatures in the Indian Ocean.

"Our study indicates that in addition to being responsible for some of the year-to-year changes in East African climate, ENSO may also set the pace for slower decadal changes," said Cole.

ENSO refers to oceanic and atmospheric fluctuations that originate in the tropical Pacific and affect climate in various areas across the globe.

"Only when we have a long-term perspective can we say anything at all about long-term variability, especially decadal variability," said Cole.

The study provides clues to the role oceans play in the grand global climate scheme. It will also help forecasters better predict the weather.

"One new piece of information the long-term perspective gives us is that the temperature in the region over the last decade was warmer than during the past two centuries," said Cole. "There are not many records of actual ocean temperatures, so adding ocean measurements to the pool, that's one more piece of information that makes a strong case something unusual is going on."

The unusual occurrence is global warming.

"When there's a long record of climate, like the one from the coral, we can ask the question of whether recent warm conditions are unusual or part of a natural cycle," said Cole. "What we found is just one of many cycles that show warming is not part of the natural cycle.

The scientists didn't directly study the effects of El Niño's warm water on the coral. But they note that when seawater gets unusually warm, coral suffers.

"Many corals die when sea temperature exceeds 31 degrees centigrade (94 degrees Fahrenheit)," said Tim McClanahan of the Wildlife Conservation Society and a member of the research team. "The effects of El Niño have killed many of the corals in the western Indian Ocean, despite being far from the center of the El Niño phenomenon. Our study shows that we can expect more warming and coral mortality in the future, which is making local and national management of reefs difficult."

The researchers studied a resilient, abundant coral off the coast of Kenya with growth rings dating back to 1801. They found this living thermometer, called Porites lutea, about 20 feet underwater near Malindi Marine Park. They drilled a small core through the 12-foot-tall coral and assessed the colony.

Chemical changes in the rings tell the story of sea temperature. When the water is warm, the coral reveals light oxygen. When the water is cold, the coral is saturated with heavy oxygen. [See isotopes].

"We cored up and down the Kenya coast, from the Tanzanian border to Malindi," said Cole. "We had the advantage of local ecologists on the project with us, and they helped us find the best sites."


Cole, McClanahan, Robert Dunbar of Stanford University and Nyawira Muthiga of the Kenya Wildlife Service collaborated on the report, which was published in the Jan. 28 issue of Science.

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