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 |