HISTORY OF EARTH

PRESENTED BY : MARIELLE TRINIDAD, ZYREX DIMAANDAL, MAIRA

ASUNCION, KURT PUNZALAN, LOUIS ALCAZAR, DEAN MACALINTAL,
SELWYN GONZALES, KRISTINE PADILLA, AISSA JAVIER
 PRE CAMBRIAN ERA
• PRE CAMBRIAN STARTED WITH THE ORIGIN OF THE EARTH ABOUT 4.5
BILLION YEARS AGO AND ENDED ABOUT 570 MILLION YEARS AGO.
• Largely thought to be a hot, steaming, and forbidding landscape, the
primitive crust of the newly condensed planet continued to cool.
• The crust consisted largely of igneous intrusions and volcanic rocks, and
sediments that were eroded from this irregular surface.
• Geologic remnants from this time are the highly deformed and
metamorphosed cratons of the continents.
The Precambrian is
subdivided, from oldest to
youngest, into three eons
 HADEAN (4600−3900 million years ago)
• Little is known about Hadean because the numbers of rocks of that age is
very few and those that do exist are intensely deformed and
metamorphosed
• characterized by Earth’s initial formation—from the accretion of dust
and gases and the frequent collisions of larger planetismals and by the
stabilization of its core and crust and the development of
its atmosphere and oceans.
• Throughout part of the eon, impacts from extraterrestrial bodies released
enormous amounts of heat that likely prevented much of the rock from
solidifying at the surface.
• From the name Hades, a Greek translation of the Hebrew word for hell.
 Archean (3900−2500 million years ago)
• It was dominated by crustal building and the development of
extensive volcanic belts, arcs, and sedimentary basins that were
probably related to plate tectonic activity. Marine rocks including
chert contain the fossil remains of microscopic algae and bacteria
• the period when life first formed on Earth.
• Began about 4 billion years ago with the formation of Earth’s crust
• Records of Earth’s primitive atmosphere and oceans emerge in the
earliest Archean. Fossil evidence of the earliest primitive life forms
prokaryotic microbes from the domain called Archaea and Archean
greenstone-granite belts contain many economic mineral deposits,
including gold and silver.
 Proterozoic (2500−570 million years ago)
• large‐scale rifting of continental crust across the world and the
filling of these rifts with huge amounts of sedimentary and volcanic
rocks.
• divided into the Paleoproterozoic, Mesoproterozoic, and the
Neoproterozoic eras.
• Proterozoic rocks have been identified on all the continents and
often constitute important sources of metallic ores, notably
of iron, gold, copper, uranium, and nickel.
• During the Proterozoic, the atmosphere and oceans changed
significantly. Proterozoic rocks contain many definite traces of
primitive life forms the fossil remains of bacteria and blue-green
algae, and the first oxygen-dependent animals, Ediacara fauna.
•The increase in the amount of free oxygen
is thought to be a result of photosynthetic
action by primitive life forms in the sea.
•The fossil record has preserved layered
algal mounds called stromatolites, an
abundance of microscopic species, and
trails and burrows from wormlike
organisms.
Paleoproterozoic Era
• First era of Proterozoic eon.
• begins at the time from which the oldest known glacial
deposits are from, and ends with the first appearance of
sulphidic marine deposits.
• Early photosynthesis would cause the Great Oxygenation
Event that would mean extinction for most of the planet's
anaerobic bacteria, allowing for aerobic lifeforms to become
dominant and evolve into multicellular life, as the first
multicellular Eukaryotes evolved during this era. Formation of
the supercontinent of Columbia, which would last into the
Mesoproterozoic.
• sudden abundance of complex organisms with hard parts in
the fossil record. These organisms included trilobites and
shelled animals called cephalopods. Life was restricted to
the sea and included graptolites, brachiopods, bryozoans,
and mollusks.
• A single southern landmass consisted of what is today South
America, Africa, India, Antarctica, and Australia. In the
northern hemisphere, land masses that represent North
America, Siberia, northern Europe, western Asia, and China
had not yet joined the southern landmass. North America
was essentially a lowland that was periodically flooded by
the ocean, forming extensive deposits of sandstone,
limestone, and barrier reefs.
PANGAEA
• By the end of the Paleozoic, all of the continents had come
together to form Pangaea. It resulted in extreme seasonal
weather conditions and one of the greatest periods of
extinction in the earth's history up to 75 percent of amphibian
species and 80 percent of marine species disappeared.
• Marked by the rapid development of land plants, forests of
short trees, armor‐plated fishes, sharks, and bony fishes.
• The Devonian period, the fourth period in the Paleozoic era, is
known as the “Age of the Fishes.” Air‐breathing amphibians
began to move from the ocean to land. Large tropical swamps
dominated much of the landscape.
Mesoproterozoic Era
• occurred from about 245 million to 66 million years ago. The
fossil record from this era (the “Age of the Dinosaurs”) is
dominated by a multitude of dinosaur species.
• Common sedimentary deposits are red sandstones and
mudstones. The low‐lying areas were frequently flooded by
shallow marine transgressions.
• Tropical conditions resulted in extensive swamps that later
became coal beds.
• By the mid‐Mesozoic, Pangaea rifted into northern Laurasia
and southern Gondwanaland. Igneous and volcanic activity
formed the mountain ranges in western North America.
•In the Mesozoic era, new trees such as conifers
and ginkgoes appeared. Reptiles laid eggs on
land. Dinosaur species included meat-eaters,
herbivores, winged reptiles, and marine reptiles.
•Mammals were beginning to emerge during this
time. The end of the Mesozoic is marked by
more mass extinctions, especially of the
dinosaurs.
•Surviving species included turtles, snakes,
crocodiles, and various lizards.
Neoproterozoic Era
•Extending from 1000 to 541 million years ago,
it stands at the intersection of the two great
tracts of evolutionary time on the one side,
some three billion years of pervasively
microbial ‘Precambrian’ life, and on the other
the modern ‘Phanerozoic’ biosphere with its
extraordinary diversity of large multicellular
organisms.
•Last of the Precambrian Supereon and the
Proterozoic Eon
Cenozoic Era
• also called the “Age of Recent Life” or “Age of Mammals,”
encompasses the last 66 million years of the earth's history.
The Cenozoic has the most complete geologic record of any
era because it is so recent. The continents were fully
separated. Plate tectonic activity created many orogenic
and volcanic events in North America, including the western
fault‐block mountains and huge lava flows.
• Eastern North America was tectonically stable, and the
Appalachians eroded to lower elevations. Valleys in the
western part of the continent were filled with great
thicknesses of sediments from the mountain ranges.
• The fossil record indicates a diverse array of mammals
(including marsupials and placentals), flowering plants,
grasses, and microscopic foraminifera.
• New birds and mammals evolved that were adapted to
the new vegetation species. Prehistoric humans also
began to emerge. Waves of mass extinctions occurred
toward the end of Pleistocene epoch, including those of
mammoths, mastodons, sabertoothed cats, ground
sloths, and camels.
• North America underwent multiple glaciations in the last
20,000 years, which helped mold the landscapes we see
today.