Meteorite fall statistics

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Template:Short description Meteorite fall statistics are frequently used by planetary scientists to approximate the true flux of meteorites on Earth. Meteorite falls are those meteorites that are collected soon after being witnessed to fall, whereas meteorite finds are discovered at a later time. Although there are 30 times as much finds than falls, their raw distribution of types does not accurately reflect what falls to Earth. The reasons for this include the following:

  • Some meteorite types are easier to find than others.
  • Some meteorite types are degraded by weathering more quickly than others.[1]
  • Some meteorites, especially iron meteorites, may have been collected by people in the past who recognized them as being unusual and/or useful, thereby removing them from the scientific record.
  • Many meteorites fall as showers of many stones, but when they are collected long after the event it may be difficult to tell which ones were part of the same fall.
  • Many meteorites are found by people who sell meteorites... valuable, rare types become known to science quickly, while those of low value may never be described.

There have been many attempts to correct statistical analyses of meteorite finds for some of these effects, especially to estimate the frequency with which rare meteorite types fall. For example, there are over 100 known lunar meteorite finds, but none has ever been observed to fall. However, for abundant types, meteorite fall statistics are generally preferred.

These statistics are current through June 9, 2012.

Statistics by material

For most meteorite falls, even those that occurred long ago or for which material has never received complete scientific characterization, it is known whether the object was a stone, stony iron, or iron meteorite. Here are the numbers and percentages of each type, based on literature data.[2][3][4]

Material Number %
Iron meteorites 49 2%[5]
Stony-iron meteorites 11 1.0%
Stony meteorites 1042 94.6%
Total 1102 100.0%

Statistics by major category

The traditional way of subdividing meteorites (see Meteorites classification) is into irons, stony-irons, and two major groups of stony meteorites, chondrites and achondrites. For some of the less-studied stony meteorite falls, it is not known whether the object is chondritic; thus the number of meteorites that can be so grouped is 4% lower than shown above. These numbers are shown in the next table. One could make a slight correction for the undercounting of stony meteorites (e.g., the percentage of irons would decrease by a 0.2%), but this was not done.

Category Number %
Irons 49 4.6%
Stony irons 11 1.0%
Achondrites 86 8.2%
Chondrites 915 86.2%
Total 1062 100.0%

Statistics by meteorite group

Probably the most useful statistical breakdown of meteorite falls is by group, which is the fundamental way that meteorites are classified. About 5% of the meteorites in the table just above have not been sufficiently classified to allow them to be put into such groups. Again, a small adjustment could be made to the percentages to correct for this effect, but it does not greatly change the results. Note that a number of meteorite groups are only represented by a small number of falls; the percentages of falls belonging to these groups have a large uncertainty.

Group N %
Iron meteorites
IAB complex 10 1.0%
IC 0 0.0%
IIAB 6 0.6%
IIC 0 0.0%
IID 3 0.3%
IIE 2 0.2%
IIF 1 0.1%
IIG 0 0.0%
IIIAB 11 1.1%
IIIE 0 0.0%
IIIF 0 0.0%
IVA 4 0.4%
IVB 0 0.0%
Ungrouped 4 0.4%
Stony Iron meteorites
Mesosiderite 7 0.7%
Pallasite 4 0.4%
Group N %
Achondrites
Acapulcoite 1 0.1%
Lodranite 1 0.1%
Angrite 1 0.1%
Aubrite 9 0.9%
Diogenite 11 1.2%
Eucrite 34 3.4%
Howardite 16 1.6%
Brachinite 0 0.0%
Ureilite 6 0.6%
Winonaite 1 0.1%
Ungrouped 2 0.2%
Lunar 0 0.0%
Martian 5 0.5%
Group N % Class total
Chondrites
CB 1 0.1% Carbonaceous:
4.4%
CH 0 0.0%
CI 5 0.5%
CK 2 0.2%
CM 15 1.5%
CO 6 0.6%
CR 2 0.2%
CV 7 0.7%
C ungrouped 6 0.6%
EH 8 0.8% Enstatite:
1.6%
EL 8 0.8%
H 339 33.8% Ordinary:
80.0%
H/L 1 0.1%
L 371 37.0%
L/LL 9 0.9%
LL 82 8.2%
R 1 0.1% Other:
0.2%
K 1 0.1%
Grand Total: 1003 meteorites

Statistics by country

Country N
Template:Country data Afghanistan 2
Template:Country data Algeria 7
Template:Country data Angola 3
Template:Country data Argentina 24
Template:Country data Armenia 2
Template:Country data Australia 16
Template:Country data Austria 4
Template:Country data Azerbaijan 2
Template:Country data Bangladesh 8
Template:Country data Belarus 3
Template:Country data Belgium 3
Template:Country data Bosnia and Herzegovina 1
Template:Country data Brazil 22
Template:Country data Bulgaria 6
Template:Country data Burkina Faso 8
Template:Country data Burma 3
Template:Country data Cambodia 2
Template:Country data Cameroon 3
Template:Country data Canada 16
Template:Country data Central African Republic 1
Template:Country data Chad 1
Template:Country data Chile 1
Template:Country data People's Republic of China 58
Template:Country data Colombia 1
Template:Country data Costa Rica 1
Template:Country data Croatia 4
Template:Country data Czech Republic 15
Country N
Template:Country data DR Congo 5
Template:Country data Denmark 4
Template:Country data Ecuador 1
Template:Country data Egypt 2
Template:Country data Estonia 3
Template:Country data Ethiopia 5
Template:Country data Finland 5
Template:Country data France 63
Template:Country data Germany 32
Template:Country data Ghana 1
Template:Country data Greece 1
Template:Country data Hungary 6
Template:Country data India 127
Template:Country data Indonesia 16
Template:Country data Iran 2
Template:Country data Iraq 2
Template:Country data Ireland 6
Template:Country data Italy 31
Template:Country data Japan 42
Template:Country data Jordan 1
Template:Country data Kazakhstan 6
Template:Country data Kenya 4
Template:Country data Latvia 4
Template:Country data Lebanon 1
Template:Country data Lesotho 1
Template:Country data Libya 1
Template:Country data Lithuania 4
Template:Country data Madagascar 1
Country N
Template:Country data Malawi 5
Template:Country data Mali 2
Template:Country data Mauritania 3
Template:Country data Mauritius 1
Template:Country data Mexico 19
Template:Country data Mongolia 4
Template:Country data Morocco 6
Template:Country data Namibia 2
Template:Country data Netherlands 4
Template:Country data New Caledonia 1
Template:Country data New Zealand 1
Template:Country data Niger 9
Template:Country data Nigeria 14
Template:Country data Norway 9
Template:Country data Pakistan 15
Template:Country data Papua New Guinea 2
Template:Country data Paraguay 1
Template:Country data Peru 1
Template:Country data Philippines 4
Template:Country data Poland 11
Template:Country data Portugal 6
Template:Country data Romania 7
Template:Country data Russia 47
Template:Country data Rwanda 1
Template:Country data Saudi Arabia 4
Template:Country data Serbia 4
Template:Country data Slovakia 3
Country N
Template:Country data Slovenia 5
Template:Country data Somalia 2
Template:Country data South Africa 21
Template:Country data South Korea 3
Template:Country data South Sudan 3
Template:Country data Spain 23
Template:Country data Sri Lanka 1
Template:Country data Sudan 7
Template:Country data Swaziland 1
Template:Country data Sweden 9
Template:Country data Switzerland 4
Template:Country data Syria 1
Template:Country data Tanzania 8
Template:Country data Thailand 3
Template:Country data Tunisia 5
Template:Country data Turkey 12
Template:Country data Turkmenistan 2
Template:Country data Uganda 5
Template:Country data Ukraine 32
Template:Country data United Kingdom 18
Template:Country data United States 146
Template:Country data Uzbekistan 2
Template:Country data Venezuela 2
Template:Country data Vietnam 3
Western SaharaTemplate:Efn 3
Template:Country data Yemen 2
Template:Country data Zambia 1
Template:Country data Zimbabwe 2
Grand Total: 1106 meteorites

Statistics by continent and time

Epoch Europe Asia North
America		 Africa South
America		 Oceania Total
Pre-1400 1 1 2
1400s 4 4
1500s 2 2
1600s 9 3 12
1700s 25 3 28
1800–1820 31 7 3 1 42
1821–1840 26 11 9 1 1 48
1841–1860 42 15 12 1 70
1861–1880 47 36 14 6 4 1 108
1881–1900 36 27 20 7 2 92
1901–1920 27 55 21 10 4 2 119
1921–1940 38 55 32 17 14 5 161
1941–1960 27 27 18 31 12 3 118
1961–1980 19 42 22 29 8 3 123
1981–2000 12 49 19 24 4 2 110
2001- 11 15 12 16 7 2 63
Total 357 346 121 144 53 20 1102

Notes

Template:Notelist

See also

References

Template:Reflist

Template:Meteorites

  1. ↑ Script error: No such module "Citation/CS1".
  2. ↑ Script error: No such module "citation/CS1".
  3. ↑ The NHM Catalogue of Meteorites
  4. ↑ MetBase
  5. ↑ Script error: No such module "Citation/CS1".
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