Meteorite Classification Table

隕石分類表

(Click on letter designations for photo catalogs and information pages for specific meteorites.)

點擊字母命名查找隕石的照片和具體隕石的信息

Category 種類

Composition Type構成形式

Distinguishing Features/ Chondrule Character
區別特徵/ 球粒特性

Letter Designation

對應代號

Chondrites球粒隕石

Stony Meteorites are characterized by chondrules--small spheres (average diameter of 1 mm) of formerly melted minerals that have come together with other mineral matter to form a solid rock. Chondrites are believed to be among the oldest rocks in the solar system. percent of meteorite falls are chondrites.

Number designations for chondrites: Most classified chondrites are given a number designation. The number refers to the alteration of the chondrules. A designation of "3" indicates unaltered chondrules. Numbers greater than 3 indicate increasing thermal metamorphism. A designation of 7 indicates complete obliteration of chondrules. Numbers less than three indicate increasing aqueous alteration. A designation of 1 indicates that chondrules have been obliterated by aqueous alteration. A lack of numeric designation means that no alteration designation has been assigned.

石隕石是具有隕石球粒特徵(平均直徑1mm)預先融化的礦物與其他礦物碰到一起形成的一種固體岩石. 球粒隕石被看做是太陽系最古老的岩石. 

82 %的隕石是球粒隕石.

球粒隕石的數字命名: 
大多數分類的球粒隕石都有一個數字命名. 數字命名是叁考了球粒隕石的變異(alteration). 命名"3"表示隕石球粒無變異. 數字大於3的表示熱變形增強. 數字 7 表示隕石球粒完全變異消失. 數字小於 3 的表示水的變異增強. 數字 1 表示隕石球粒已經經過水的變異而消失. 沒有數字命名的代表了沒有變異.

Note on type 7 Chondrites. There is no firm agreement among meteorite researchers on the definition of type 7 chondrites. Many meteorites previously described as type 7 are either type 6 or are impact melts. Impact melting is not considered a proper basis for type 7 classification. Future research is expected to clear up this issue.

命名 "7" 型球粒隕石備註  
關於命名 "7" 型球粒隕石的定義在隕石研究人員中沒有達成一致的定義. 許多隕石早先被描述為 7 型的有可能是代號 6 的或是撞擊融合物. 撞擊融合物並不被認為是 7型的合理原理, 未來的研究有希望釐清這種情況.

Enstatite Chondrites

Letter Designations: The E stands for Enstatite. H indicates high metallic iron and L indicates low metallic iron. Very Rare--1.5% of falls. Minerals:  Enstatite, metal, sulfides, plagioclase, and occasional olivine (EH).

頑火輝石球粒隕石

以字母命名:
E代表頑火輝石(Enstatite) ,H代表含有高量金屬鐵,L代表含有低量金屬鐵,此類隕石非常稀少, 佔落下總量的1.5%,主要礦物組成:頑火輝石, 隕硫鐵,硫化物,斜長石和偶時出現的橄欖石(EH).

Abundant 充足

E3, EH3, EL3

Distinct 明顯

E4, EH4. EL4

Less Distinct較不明顯

E5, EH5, EL5

Indistinct難以清楚辨認

E6, EH6, EL6

Melted*融合一起

E7

Ordinary Chondrites

The most common meteorite from observed falls--73.5%.

The initial letter designation for ordinary Chondrites, "O", is usually deleted. Brecciated meteorites with clasts of more than one type of alteration are designated with the range of alteration present in the meteorite. The letter designation refers to the iron content for the meteorite as a whole. E.g., Zag bears the designation H3-6.

Some meteorites are classified as transitional between the main groups, e.g., H/L, L/LL

When a researcher is not sure of a class, it may be designated with a notation like L(LL) with the less certain class being in parentheses.

普通球粒隕石

普通球粒隕石是最普遍的目擊墬落隕石--佔隕石墬落總量的73.5%

以首字母命名的普通球粒隕石0通常是被刪除的

帶有超過一種變異的碎屑合成角礫岩狀隕石 由隕石目前的變異程度來命名, 字母命名的是叁考整體隕石鐵的含量. 例如 Zag隕石歸類為H3-6

有些隕石被歸類於過渡的兩個主要群組之間 例如,H/L,L/LL

如果研究者不確定分類, 他也許以L(LL)記號, 將比較不確定的分類放置於括弧中

H Chondrites

High Iron (12 to 21% metallic iron) (also called Bronzite Chondrites) 31.4% of falls. Minerals:  Olivine, pyroxene, metal, plagioclase, sulfide.

H 球粒隕石

高鐵(12%~21%金屬鐵)(又稱為古銅輝石球粒隕石), 佔落下總量的31.4% 主要礦物:橄欖石 輝石 隕硫鐵 斜長石 硫化物

Abundant充足

H3-H3.9*

Distinct明顯

H4

Less Distinct較不明顯

H5

Indistinct難以清楚辨認

H6

Melted*融合一起

H7

L Chondrites

Low Iron (5 to 10% metallic iron) (also called Hypersthene Chondrites) 34.8% of falls. Minerals:  Olivine, pyroxene, plagioclase, metal, sulfide.

L 球粒隕石

低鐵(5%~10%金屬鐵)(又稱為紫蘇輝石球粒隕石), 佔落下總量的34.8%主要礦物:橄欖石 輝石 斜長石 隕硫鐵 硫化物

Abundant充足

L3-L3.9*

Distinct明顯

L4

Less Distinct較不明顯

L5

Indistinct難以清楚辨認

L6

Melted*融合一起

L7

LL Chondrites

Low Metal Content (about 2% metallic iron) (also called Amphoterites) Principle minerals are bronzite, olivine, and minor oligoclase. 7.2% of falls.

LL 球粒隕石

低鐵含量(約2%金屬鐵)(又稱為古銅橄欖球粒隕石) 主要礦物:古銅輝石,橄欖石及少量的的鈉鈣長石, 佔落下總量的7.2%

Abundant充足

LL3-LL3.9*

Distinct明顯

LL4

Less Distinct較不明顯

LL5

Indistinct難以清楚辨認

LL6

Melted [* these rocks can be considered primitive achondrites and not Ordinary Chondrites]

融合一起(這些岩石被看做原始的不含球粒隕石並且不是普通的球粒隕石)

LL7

Carbonaceous Chondrites

These rare meteorites contain elemental carbon, a basic building block for life. 3.6% of falls.

Explanation of Letter Designations:

The "C" stands for Carbonaceous Chondrite. The second letter refers to type localities (except the H designation). The number refers to alteration.

碳質球粒隕石

這些稀少的隕石包含碳元,一種構成生命基礎的碳元素, 僅佔落下隕石總量的3.6%

字母命名的解釋:

"C"代表碳質球粒隕石, 第二個字母叁考了落下的位置而命名(H命名除外), 數字叁考其變異

Ivuna(隕石落下的位置)

Friable, more water. Minerals:  Phyllosilicates, magnetite

易碎的 多水 主要礦物:硅酸鹽

鐵

CI

Mighei(隕石落下的位置)

Friable, less water. Minerals: Phyllosilicates, tochilinite, olivine

易碎的 少水 主要礦物:硅酸鹽

橄欖石

CM1-CM2

Vigarano(隕石落下的位置)

Fe rich olivine, CAIs

富鐵 橄欖石CAIs

CV2-CV3.3

Renazzo(隕石落下的位置)

Minerals:  Phyllosilicates, pyroxene, olivine, metal

主要礦物:硅酸鹽 輝石 橄欖石

鐵

CR

Ornans(隕石落下的位置)

Minerals: Olivine, Pyroxene, CAIs, metal.

主要礦物:橄欖石 輝石CAIs 鐵

CO3-CO3.7

Karoonda(隕石落下的位置)

Minerals:  Olivine, CAIs

主要礦物:橄欖石CAIs

CK

Bencubbin(隕石落下的位置)

Minerals:  Metal, Pyroxene.  [ongoing research suggests the product of asteroidal collisions.]

主要礦物:鐵 輝石

CB

High Iron 高鐵

Minerals:  Pyroxene, metal, olivine.  [May be related to Bencubbinites]

主要礦物:輝石 鐵 橄欖石

CH

Kakangari-type Kakangari-類型

 Kakangari-類型

K

Rumurutiites Rumurutiites-類型

Minerals: Olivine, pyroxene, plagioclase, sulfide.

主要礦物:橄欖石 輝石 斜長石

硫化物

R

Group

Origin

Characteristic Minerals

Achondrites

Stony Meteorites without chondrules. Scientists believe that some of these meteorites originated on the surface of the Moon or Mars. 7.8 percent of meteorite falls are achondrites.

Note on Groupings:

Howardites, Eucrites, and Diogenites have been grouped as HED meteorites. These types may originate on the asteroid Vesta. Chassignites, Shergottites, and Nakhlites are grouped as SNC meteorites. These types are believed to originate on Mars.

無球粒隕石

沒有球粒的石隕石. 科學家認為有些石隕石來自於火星或月球的表面.  7.8 %的隕石為無球粒隕石.

群組備註:

古銅鈣長無粒隕石, 鈣長輝長隕石及古銅無球粒隕石已經被歸類為 HED 隕石.  這些類型的隕石可能源自於灶神星. 純橄無球隕石, 輝玻無球隕石及輝橄無球隕石被歸類為 SNC 隕石. 這些類型的隕石被認為源自於火星.

Howardites古銅鈣長無球粒隕石

Vesta regolith 4號小行星-灶神星表層

Eucrite-diogenite mix

鈣長輝長隕石-古銅無球粒隕石混合

HOW

Eucrites鈣長輝長無球粒隕石

Vesta basaltic crust 4號小行星-灶神星地殼

Anorthite-pigeonite

鈣長石-易變輝石

EUC

Diogenite古銅無球粒隕石

Vesta deeper/plutonic

4號小行星灶神星深層物質或似火成岩

Hypersthene紫蘇輝石

DIO

Shergottites輝玻無球粒隕石

Marian Basalt—shocked

火星玄武岩-受撞擊

Basaltic玄武岩

SHE

Nakhlites輝橄無球粒隕石

Martian plutonic rock

火星火成岩

Diopside-olivine透輝石-橄欖石

NAK

Chassignite純橄無球粒隕石

Martian plutonic rock火星火成岩

Olivine橄欖石

CHA

Lunar月壤角礫岩

The Moon 月球

Basalt and Regolith

玄武岩及風化層表皮土

LUN

Aubrites頑火無球粒隕石

Melted E Chondrite

融合的頑火輝石球粒隕石

Enstatite頑火輝石

AUB

Acapulcoite無球粒隕石

Remelted chondrite

重新融合的球粒隕石

Olivine, Pyroxene橄欖石,輝石

ACAP

Lodranite橄欖古銅無球粒隕石

Same as ACAP--more melt

近似重新融合的球粒隕石-更融合

Olivine, Pyroxene橄欖石,輝石

LOD

Ureilites橄欖無球粒隕石

Melted C-chondrite body 融合的碳質球粒隕石的主體

Olivine-pigeonite橄欖石-易變輝石

URE

Angrite鈦輝無球粒隕石

Non-HED Basalt

非-HED 玄武岩

Olvn, Pyrx., Plagioclase橄欖石,輝石,斜長石

ANGR

Brachinite無球隕石

A or S type Asteroids

A或S型小行星

Olivine橄欖石

BRACH

Winonaite無球隕石

Like IAB & IIICD incl. 像 IAB 及 IIICD 內含物

WIN

Widmanstatten Bandwidth

維斯台登象寬度

Irons (structural classification)

These meteorites are made of a crystalline iron-nickel alloy. Scientists believe that they resemble the outer core of the Earth. 4.8 percent of meteorite falls are irons.

鐵隕石

(結構分類)

鐵隕石由結晶的鐵-鎳合金組成. 科學家認為它們類似地球的外核.  4.8%的隕石為鐵隕石. 

Hexahedrites <6% Ni. Contains kamacite, but not taenite

六方隕鐵<6% 鎳. 含鐵紋石,但無鎳紋石 

>50mm

H

Octahedrites

6% to 17% Ni. Contains both kamacite and taenite and has Widmanstatten pattern.

八面隕鐵

6% 至 17% 鎳. 同時含有鐵紋石與鎳紋石及維斯台登象. 

Coarsest最粗的

3.3-50mm

Ogg

Coarse粗的

1.3-3.3mm

Og

Medium中等

.5-1.3mm

Om

Fine纖細的

0.2-0.5mm

Of

Finest最細的

0.2mm

Off

Plessitic隕合紋石

0.2mm Kamacite spindles鐵紋石紡錘體

Opl

Ataxites High Ni content無紋隕鐵高鎳含量

(no structure)無結構

D

Minerals礦物

Structural Classes結構分類

Irons (Chemical Classification)

A second scheme for classifying iron meteorites is by their chemistry. The determining factors are groupings of meteorites with similar ratios of trace elements to nickel. Generally, the higher the Roman numeral of the classification, the lower the concentration of trace elements. The casual observer cannot see this as one can with the Widmanstatten bandwidth that is the determining factor for structural classification. Chemical classification is important because it suggests that certain iron meteorites share a common origin or were formed under similar conditions. The Handbook of Iron Meteorites by Vahn Buchwald has a more complete description.

鐵隕石 (化學分類)

分類鐵隕石的第二種方法就是根據它們的化學成分. 決定分類的關鍵在於恆量元素的比率接近鎳元素. 總的來說,分類的羅馬數字愈高, 恆量元素的聚集就越低. 與結構分類的維斯台登交紋寬度分類做比較, 一般的觀察者無法了解化學分類. 化學分類是很重要是因為它提出同一種類的鐵隕石有著共同的來源或是在相似的條件下形成.

kamacite, taenite, silicates, carbides

鐵紋石,鎳紋石,硅酸塩,碳化物　

Om-Og

IAB

kamacite, taenite, silicates, carbides

鐵紋石,鎳紋石,硅酸塩,碳化物　

Om-Og

IC

kamacite, taenite, (daubreelite)

鐵紋石,鎳紋石,(隕硫鉻鐵礦)　

Ogg, H

IIAB

kamacite, taenite

鐵紋石,鎳紋石

Ogg

IIC

kamacite, taenite

鐵紋石,鎳紋石

Of-Om

IID

kamacite, taenite,

鐵紋石,鎳紋石

Off-Og

IIE

kamacite, taenite,

鐵紋石,鎳紋石

Plessitic Oct., Atax.

IIF

kamacite, taenite, troilite, phosphides

鐵紋石,鎳紋石,,隕硫鐵,磷化物

Om-Og

IIIAB

kamacite, taenite, carbides

鐵紋石,鎳紋石,碳化物

Off-D

IIICD

kamacite, taenite, carbides, graphite

鐵紋石,鎳紋石,碳化物,石墨　

Og

IIIE

kamacite, taenite

鐵紋石,鎳紋石

Om-Og

IIIF

kamacite, taenite

鐵紋石,鎳紋石

Of

IVA

kamacite, taenite

鐵紋石,鎳紋石

D

IVB

kamacite, taenite, silicates, graphite

鐵紋石,鎳紋石,硅酸塩,石墨

All

Anom

Primary Minerals原生礦物

Stony Irons

These meteorites are mixtures of iron-nickel alloy and non-metallic mineral matter. Scientists believe that they are like the material that would be found where the Earth's core meets the mantle. 1.2 percent of meteorite falls are stony irons.

石鐵隕石

石鐵隕石是鐵-鎳與非金屬礦物體的混合物. 科學家們認為它們像地球的核心與地幔交界處所發現的物質相似.  1.2 %的落下的隕石為石鐵隕石.

Pallasites橄欖石石鐵隕石

Main-group Pallasites

iron, olivine 鐵 橄欖石

PAL

Eagle Station grouplet

iron, olivine, pyroxene

鐵 橄欖石 輝石

Pyroxene Pallasite grouplet

iron, pyroxene 鐵 輝石

Mesosiderites (MES) 中鐵隕石

Mesosiderites have been divided into a classification grid that resembles that for chondrites. There are three broad petrologic groups designated A, B, and C. Within these groups there is a numeric classification of metamorphic grade. Grade 1 is fine grained and fragmental, 2 and 3 show progressive recrystallization, and 4 is a melt breccia.

中鐵隕石已經被化分成為一種分類 類似球粒隕石 有三種大範圍的岩石學群體 設計為等級A B C 在這些群體內有隕石等級的數字分類 1級為細微難觀察的粒化碎片

2級3級表示更近一步的再結晶 4級是一個融解的角礫岩.

Class A (Basaltic)

級別A 玄武岩

iron, Ca pyroxene, plagioclase

鐵 鈣輝石 斜長石

1A

2A

3A

4A

Class B (Ultramafic)

級別B

iron, Ca pyroxene, plagioclase, Orthopyroxene

鐵 鈣輝石 斜長石 原輝石

1B

2B

3B

Class C (Orthopyroxene)

級別 C 原輝石

Orthopyroxene 原輝石

2C