What is the age of earth?

Question

thanks for sharing answers. really appreciated it.

Answer 1

a few billion years

Answer 2

a few billion years i believe...

Common creationist "dating methods"

Common creationist criticisms of mainstream dating methods

Suggested further reading

References

How Old Is The Earth, And How Do We Know?

he generally accepted age for the Earth and the rest of the solar system is about 4.55 billion years (plus or minus about 1%). This value is derived from several different lines of evidence.

Unfortunately, the age cannot be computed directly from material that is solely from the Earth. There is evidence that energy from the Earth's accumulation caused the surface to be molten. Further, the processes of erosion and crustal recycling have apparently destroyed all of the earliest surface.

The oldest rocks which have been found so far (on the Earth) date to about 3.8 to 3.9 billion years ago (by several radiometric dating methods). Some of these rocks are sedimentary, and include minerals which are themselves as old as 4.1 to 4.2 billion years. Rocks of this age are relatively rare, however rocks that are at least 3.5 billion years in age have been found on North America, Greenland, Australia, Africa, and Asia.

While these values do not compute an age for the Earth, they do establish a lower limit (the Earth must be at least as old as any formation on it). This lower limit is at least concordant with the independently derived figure of 4.55 billion years for the Earth's actual age.

The most direct means for calculating the Earth's age is a Pb/Pb isochron age, derived from samples of the Earth and meteorites. This involves measurement of three isotopes of lead (Pb-206, Pb-207, and either Pb-208 or Pb-204). A plot is constructed of Pb-206/Pb-204 versus Pb-207/Pb-204.

If the solar system formed from a common pool of matter, which was uniformly distributed in terms of Pb isotope ratios, then the initial plots for all objects from that pool of matter would fall on a single point.

Over time, the amounts of Pb-206 and Pb-207 will change in some samples, as these isotopes are decay end-products of uranium decay (U-238 decays to Pb-206, and U-235 decays to Pb-207). This causes the data points to separate from each other. The higher the uranium-to-lead ratio of a rock, the more the Pb-206/Pb-204 and Pb-207/Pb-204 values will change with time.

If the source of the solar system was also uniformly distributed with respect to uranium isotope ratios, then the data points will always fall on a single line. And from the slope of the line we can compute the amount of time which has passed since the pool of matter became separated into individual objects. See the Isochron Dating FAQ or Faure (1986, chapter 18) for technical detail.

A young-Earther would object to all of the "assumptions" listed above. However, the test for these assumptions is the plot of the data itself. The actual underlying assumption is that, if those requirements have not been met, there is no reason for the data points to fall on a line.

The resulting plot has data points for each of five meteorites that contain varying levels of uranium, a single data point for all meteorites that do not, and one (solid circle) data point for modern terrestrial sediments. It looks like this:

Pb-Pb isochron of terrestrial and meteorite samples.

After Murthy and Patterson (1962) and York and Farquhar (1972) .

Scanned from Dalrymple (1986) with permission.  

Most of the other measurements for the age of the Earth rest upon calculating an age for the solar system by dating objects which are expected to have formed with the planets but are not geologically active (and therefore cannot erase evidence of their formation), such as meteorites. Below is a table of radiometric ages derived from groups of meteorites:

--------------------------------------...



Type Number

Dated Method Age (billions

of years)

--------------------------------------...



Chondrites (CM, CV, H, L, LL, E) 13 Sm-Nd 4.21 +/- 0.76

Carbonaceous chondrites 4 Rb-Sr 4.37 +/- 0.34

Chondrites (undisturbed H, LL, E) 38 Rb-Sr 4.50 +/- 0.02

Chondrites (H, L, LL, E) 50 Rb-Sr 4.43 +/- 0.04

H Chondrites (undisturbed) 17 Rb-Sr 4.52 +/- 0.04

H Chondrites 15 Rb-Sr 4.59 +/- 0.06

L Chondrites (relatively undisturbed) 6 Rb-Sr 4.44 +/- 0.12

L Chondrites 5 Rb-Sr 4.38 +/- 0.12

LL Chondrites (undisturbed) 13 Rb-Sr 4.49 +/- 0.02

LL Chondrites 10 Rb-Sr 4.46 +/- 0.06

E Chondrites (undisturbed) 8 Rb-Sr 4.51 +/- 0.04

E Chondrites 8 Rb-Sr 4.44 +/- 0.13

Eucrites (polymict) 23 Rb-Sr 4.53 +/- 0.19

Eucrites 11 Rb-Sr 4.44 +/- 0.30

Eucrites 13 Lu-Hf 4.57 +/- 0.19

Diogenites 5 Rb-Sr 4.45 +/- 0.18

Iron (plus iron from St. Severin) 8 Re-Os 4.57 +/- 0.21

--------------------------------------...



After Dalrymple (1991, p. 291); duplicate studies on identical meteorite types omitted.  

As shown in the table, there is excellent agreement on about 4.5 billion years, between several meteorites and by several different dating methods. Note that young-Earthers cannot accuse us of selective use of data -- the above table includes a significant fraction of all meteorites on which isotope dating has been attempted. According to Dalrymple (1991, p. 286) , less than 100 meteorites have been subjected to isotope dating, and of those about 70 yield ages with low analytical error.

Further, the oldest age determinations of individual meteorites generally give concordant ages by multiple radiometric means, or multiple tests across different samples. For example:

--------------------------------------...



Meteorite Dated Method Age (billions

of years)

--------------------------------------...



Allende whole rock Ar-Ar 4.52 +/- 0.02

whole rock Ar-Ar 4.53 +/- 0.02

whole rock Ar-Ar 4.48 +/- 0.02

whole rock Ar-Ar 4.55 +/- 0.03

whole rock Ar-Ar 4.55 +/- 0.03

whole rock Ar-Ar 4.57 +/- 0.03

whole rock Ar-Ar 4.50 +/- 0.02

whole rock Ar-Ar 4.56 +/- 0.05



Guarena whole rock Ar-Ar 4.44 +/- 0.06

13 samples Rb-Sr 4.46 +/- 0.08



Shaw whole rock Ar-Ar 4.43 +/- 0.06

whole rock Ar-Ar 4.40 +/- 0.06

whole rock Ar-Ar 4.29 +/- 0.06



Olivenza 18 samples Rb-Sr 4.53 +/- 0.16

whole rock Ar-Ar 4.49 +/- 0.06



Saint Severin 4 samples Sm-Nd 4.55 +/- 0.33

10 samples Rb-Sr 4.51 +/- 0.15

whole rock Ar-Ar 4.43 +/- 0.04

whole rock Ar-Ar 4.38 +/- 0.04

whole rock Ar-Ar 4.42 +/- 0.04



Indarch 9 samples Rb-Sr 4.46 +/- 0.08

12 samples Rb-Sr 4.39 +/- 0.04



Juvinas 5 samples Sm-Nd 4.56 +/- 0.08

5 samples Rb-Sr 4.50 +/- 0.07



Moama 3 samples Sm-Nd 4.46 +/- 0.03

4 samples Sm-Nd 4.52 +/- 0.05



Y-75011 9 samples Rb-Sr 4.50 +/- 0.05

7 samples Sm-Nd 4.52 +/- 0.16

5 samples Rb-Sr 4.46 +/- 0.06

4 samples Sm-Nd 4.52 +/- 0.33



Angra dos Reis 7 samples Sm-Nd 4.55 +/- 0.04

3 samples Sm-Nd 4.56 +/- 0.04



Mundrabrilla silicates Ar-Ar 4.50 +/- 0.06

silicates Ar-Ar 4.57 +/- 0.06

olivine Ar-Ar 4.54 +/- 0.04

plagioclase Ar-Ar 4.50 +/- 0.04



Weekeroo Station 4 samples Rb-Sr 4.39 +/- 0.07

silicates Ar-Ar 4.54 +/- 0.03

--------------------------------------...



After Dalrymple (1991, p. 286); meteorites dated by only a single means omitted.  

Also note that the meteorite ages (both when dated mainly by Rb-Sr dating in groups, and by multiple means individually) are in exact agreement with the solar system "model lead age" produced earlier.

Common Young-Earth "Dating Methods"

Young-Earthers have several methods which they claim to give "upper limits" to the age of the Earth, much lower than the age calculated above (usually in the thousands of years). Those which appear the most frequently in talk.origins are reproduced below:

Accumulation of helium in the atmosphere

Decay of the Earth's magnetic field

Accumulation of meteoritic dust on the Moon

Accumulation of metals into the oceans

Note that these aren't necessarily the "best" or most difficult to refute of young-Earth arguments. However, they are quite popular in modern creation-"science" literature (even though they should not be!) and they are historically the ones posted to talk.origins more than any others.

1. Accumulation of Helium in the atmosphere

The young-Earth argument goes something like this: helium-4 is created by radioactive decay (alpha particles are helium nuclei) and is constantly added to the atmosphere. Helium is not light enough to escape the Earth's gravity (unlike hydrogen), and it will therefore accumulate over time. The current level of helium in the atmosphere would accumulate in less than two hundred thousand years, therefore the Earth is young. (I believe this argument was originally put forth by Mormon young-Earther Melvin Cook, in a letter to the editor which was published in Nature.)

But helium can and does escape from the atmosphere, at rates calculated to be nearly identical to rates of production. In order to obtain a young age from their calculations, young-Earthers handwave away mechanisms by which helium can escape. For example, Henry Morris says:

"There is no evidence at all that Helium 4 either does, or can, escape from the exosphere in significant amounts." ( Morris 1974, p. 151 )

But Morris is wrong. Surely one cannot "invent" a good dating mechanism by simply ignoring processes which work in the opposite direction of the process which the date is based upon. Dalrymple says:

"Banks and Holzer (12) have shown that the polar wind can account for an escape of (2 to 4) x 106 ions/cm2 /sec of 4He, which is nearly identical to the es

Answer 3

Many different ages vary, but most believe it's around 4.2-4.5 billion years old

Answer 4

Modern geologists and geophysicists consider the age of the Earth to be around 4.54 billion years (4.54×10^9 years).

Answer 5

It is two weeks old....anything that shows it is any older than that was put there by the Aliens who created it.

Including the memories that you have.

Answer 6

The generally accepted age for the Earth and the rest of the solar system is about 4.55 billion years (plus or minus about 1%). This value is derived from several different lines of evidence.

Unfortunately, the age cannot be computed directly from material that is solely from the Earth. There is evidence that energy from the Earth's accumulation caused the surface to be molten. Further, the processes of erosion and crustal recycling have apparently destroyed all of the earliest surface.

The oldest rocks which have been found so far (on the Earth) date to about 3.8 to 3.9 billion years ago (by several radiometric dating methods). Some of these rocks are sedimentary, and include minerals which are themselves as old as 4.1 to 4.2 billion years. Rocks of this age are relatively rare, however rocks that are at least 3.5 billion years in age have been found on North America, Greenland, Australia, Africa, and Asia.

While these values do not compute an age for the Earth, they do establish a lower limit (the Earth must be at least as old as any formation on it). This lower limit is at least concordant with the independently derived figure of 4.55 billion years for the Earth's actual age.

Answer 7

Hey.wat a nice question..!

Our Earth is 4.54 billion years old...!

Thanx.......Good Luck.....!

Answer 8

~4.5 billion years old

Answer 9

A few Billion, maybe 4?

Answer 10

No body knows, even with carbon 40 you do not get the age of our planet, therefore the answer is billions of years,which man can not calculate, The orbit of earth round the sun,gives time, but that is only an idea, cause time is not understood and we do not know nothing about it,

Answer 11

about 4.5 billion years

Answer 12

scientists estimate it to be 4.5 billion years old when dust all gathered to make Earth. There are many other ideals (ie some religions think its only been around for a few thousand), but 4.5 billion years has theory

Answer 13

4.5 billion years, while the sun is 4.6 billion years.

Answer 14

Earth (pronounced [ˈɝːθ] (help·info))[6] is the third planet from the Sun. Earth is the largest of the terrestrial planets in the Solar System in diameter, mass and density. It is also referred to as the Earth, Planet Earth, the World, and Terra.[7]

Home to millions of species,[8] including humans, Earth is the only place in the universe where life is known to exist. Scientific evidence indicates that the planet formed 4.54 billion years ago,[9][10][11][12] and life appeared on its surface within a billion years. Since then, Earth's biosphere has significantly altered the atmosphere and other abiotic conditions on the planet, enabling the proliferation of aerobic organisms as well as the formation of the ozone layer which, together with Earth's magnetic field, blocks harmful radiation, permitting life on land.[13]

Earth's outer surface is divided into several rigid segments, or tectonic plates, that gradually migrate across the surface over periods of many millions of years. About 71% of the surface is covered with salt-water oceans, the remainder consisting of continents and islands; liquid water, necessary for all known life, is not known to exist on any other planet's surface.[14][15] Earth's interior remains active, with a thick layer of relatively solid mantle, a liquid outer core that generates a magnetic field, and a solid iron inner core.

Earth interacts with other objects in outer space, including the Sun and the Moon. At present, Earth orbits the Sun once for every roughly 366.26 times it rotates about its axis. This length of time is a sidereal year, which is equal to 365.26 solar days.[16] The Earth's axis of rotation is tilted 23.4° away from the perpendicular to its orbital plane,[17] producing seasonal variations on the planet's surface with a period of one tropical year (365.24 solar days). Earth's only known natural satellite, the Moon, which began orbiting it about 4.53 billion years ago, provides ocean tides, stabilizes the axial tilt and gradually slows the planet's rotation. A cometary bombardment during the early history of the planet played a role in the formation of the oceans.[18] Later, asteroid impacts caused significant changes to the surface environment.

Contents [hide]

1 History

2 Composition and structure

2.1 Shape

2.2 Chemical composition

2.3 Internal structure

2.4 Tectonic plates

2.5 Surface

2.6 Hydrosphere

2.7 Atmosphere

2.7.1 Weather and climate

2.7.2 Upper atmosphere

2.8 Magnetic field

3 Orbit and rotation

4 Moon

5 Habitability

5.1 Biosphere

5.2 Natural resources and land use

5.3 Natural and environmental hazards

5.4 Human geography

6 Cultural viewpoint

6.1 Etymology

6.2 Religious beliefs

6.3 Exploration and mapping

6.4 Modern perspective

7 Future

8 See also

9 Notes

10 References

11 External links



History

Main article: History of Earth

See also: Geological history of Earth

Scientists have been able to reconstruct detailed information about the planet's past. Earth and the other planets in the Solar System formed 4.54 billion years ago[9] out of the solar nebula, a disk-shaped mass of dust and gas left over from the formation of the Sun. Initially molten, the outer layer of the planet Earth cooled to form a solid crust when water began accumulating in the atmosphere. The Moon formed soon afterwards, possibly as the result of a Mars-sized object (sometimes called Theia) with about 10% of the Earth's mass[19] impacting the Earth in a glancing blow.[20] Some of this object's mass would have merged with the Earth and a portion would have been ejected into space, but enough material would have been sent into orbit to form the Moon.

Outgassing and volcanic activity produced the primordial atmosphere. Condensing water vapor, augmented by ice and liquid water delivered by asteroids and the larger proto-planets, comets, and trans-Neptunian objects produced the oceans.[18] The highly energetic chemistry is believed to have produced a self-replicating molecule around 4 billion years ago, and half a billion years later, the last common ancestor of all life existed.[21]

The development of photosynthesis allowed the Sun's energy to be harvested directly by life forms; the resultant oxygen accumulated in the atmosphere and resulted in a layer of ozone (a form of molecular oxygen [O3]) in the upper atmosphere. The incorporation of smaller cells within larger ones resulted in the development of complex cells called eukaryotes.[22] True multicellular organisms formed as cells within colonies became increasingly specialized. Aided by the absorption of harmful ultraviolet radiation by the ozone layer, life colonized the surface of Earth.[23]

Beginning with almost no dry land, the total amount of surface lying above the oceans has steadily increased. During the past two billion years, for example, the total size of the continents has doubled.[24] As the surface continually reshaped itself, over hundreds of millions of years, continents formed and broke up. The continents migrated across the surface, occasionally combining to form a supercontinent. Roughly 750 million years ago (mya), the earliest known supercontinent, Rodinia, began to break apart. The continents later recombined to form Pannotia, 600–540 mya, then finally Pangaea, which broke apart 180 mya.[25]

Since the 1960s, it has been hypothesized that severe glacial action between 750 and 580 mya, during the Neoproterozoic, covered much of the planet in a sheet of ice. This hypothesis has been termed "Snowball Earth", and is of particular interest because it preceded the Cambrian explosion, when multicellular life forms began to proliferate.[26]

Following the Cambrian explosion, about 535 mya, there have been five mass extinctions.[27] The last extinction event occurred 65 mya, when a meteorite collision probably triggered the extinction of the (non-avian) dinosaurs and other large reptiles, but spared small animals such as mammals, which then resembled shrews. Over the past 65 million years, mammalian life has diversified, and several mya, an African ape-like animal gained the ability to stand upright.[28] This enabled tool use and encouraged communication that provided the nutrition and stimulation needed for a larger brain. The development of agriculture, and then civilization, allowed humans to influence the Earth in a short time span as no other life form had,[29] affecting both the nature and quantity of other life forms.

The present pattern of ice ages began about 40 mya, then intensified during the Pleistocene about 3 mya. The polar regions have since undergone repeated cycles of glaciation and thaw, repeating every 40–100,000 years. The last ice age ended 10,000 years ago.[30]

Composition and structure

Main article: Earth science

Further information: Earth physical characteristics tables

Earth is a terrestrial planet, meaning that it is a rocky body, rather than a gas giant like Jupiter. It is the largest of the four solar terrestrial planets, both in terms of size and mass. Of these four planets, Earth also has the highest density, the highest surface gravity and the strongest magnetic field.[31]

Shape

Main article: Figure of the Earth



Size comparison of inner planets (left to right): Mercury, Venus, Earth, and MarsThe Earth's shape is very close to an oblate spheroid—a rounded shape with a bulge around the equator—although the precise shape (the geoid) varies from this by up to 100 meters.[32] The average diameter of the reference spheroid is about 12,742 km. More approximately the distance is 40,000 km/π because the meter was originally defined as 1/10,000,000 of the distance from the equator to the north pole through Paris, France.[33]

The rotation of the Earth creates the equatorial bulge so that the equatorial diameter is 43 km larger than the pole to pole diameter.[34] The largest local deviations in the rocky surface of the Earth are Mount Everest (8,848 m above local sea level) and the Mariana Trench (10,911 m below local sea level). Hence compared to a perfect ellipsoid, the Earth has a tolerance of about one part in about 584, or 0.17%, which is less than the 0.22% tolerance allowed in billiard balls.[35] Because of the bulge, the feature farthest from the center of the Earth is actually Mount Chimborazo in Ecuador.[36]

Chemical composition

See also: Abundance of elements on Earth

F. W. Clarke's Table of Crust Oxides Compound Formula Composition

silica SiO2 59.71%

alumina Al2O3 15.41%

lime CaO 4.90%

Magnesia MgO 4.36%

sodium oxide Na2O 3.55%

iron(II) oxide FeO 3.52%

potassium oxide K2O 2.80%

iron(III) oxide Fe2O3 2.63%

water H2O 1.52%

titanium dioxide TiO2 0.60%

phosphorus pentoxide P2O5 0.22%

Total 99.22%

The mass of the Earth is approximately 5.98×1024 kg. It is composed mostly of iron (32.1%), oxygen (30.1%), silicon (15.1%), magnesium (13.9%), sulfur (2.9%), nickel (1.8%), calcium (1.5%), and aluminium (1.4%); with the remaining 1.2% consisting of trace amounts of other elements. Due to mass segregation, the core region is believed to be primarily composed of iron (88.8%), with smaller amounts of nickel (5.8%), sulfur (4.5%), and less than 1% trace elements.[37]

The geochemist F. W. Clarke calculated that a little more than 47% of the Earth's crust consists of oxygen. The more common rock constituents of the Earth's crust are nearly all oxides; chlorine, sulfur and fluorine are the only important exceptions to this and their total amount in any rock is usually much less than 1%. The principal oxides are silica, alumina, iron oxides, lime, magnesia, potash and soda. The silica functions principally as an acid, forming silicates, and all the commonest minerals of igneous rocks are of this nature. From a computation based on 1,672 analyses of all kinds of rocks, Clarke  

Answer 15

About 6000 years old.

From Adam and Eve to Jesus was about 4000 then from Jesus to us is about 2000.

Answer 16

Most estimates put it between 4 and 4.5 billion years old.