Classification of meteorites is largely based on their mineralogical and petrographic characteristics and their whole-rock chemical and O-isotopic compositions According to the currently used classification scheme, meteorites are divided into chondrites, primitive achondrites, and achondrites There are 15 chondrite groups, including 8 carbonaceous (CI, CM, CO, CV, CK, CR, CH, CB), 3 ordinary (H, L, LL), 2 enstatite (EH, EL), and R and K chondrites Several chondrites cannot be assigned to the existing groups and may represent the first members of new groups Some groups are subdivided into subgroups, which may have resulted from asteroidal processing of a single group of meteorites Each chondrite group is considered to have sampled a separate parent body Some chondrite groups and ungrouped chondrites show chemical and mineralogical similarities and are grouped together into clans The significance of this higher order of classification remains poorly understood The primitive achondrites include ureilites, acapulcoites, lodranites, winonaites, and silicate inclusions in IAB and IIICD irons and probably represent recrystallization or residues from a low-degree partial melting of chondritic materials The genetic relationship between primitive achondrites and the existing groups of chondritic meteorites remains controversial Achondrites resulted from a high degree of melting of chondrites and include asteroidal (angrites, aubrites, howardites-diogenites-eucrites, mesosiderites, 3 groups of pallasites, 15 groups of irons plus many ungrouped irons) and planetary (martian, lunar) meteorites

/pdf/systematics-and-evaluation-of-meteorite-classification-4k05qo1ksk.pdf

Systematics and Evaluation of Meteorite Classification

Carlisle Lakes and Allan Hills 85151: Members of a new chondrite grouplet

OF DISSERTATION Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Earth and Planetary Sciences The University of New Mexico Albuquerque, New Mexico

Mineralogy and bulk chemistry of chondrules and matrix in petrologic type 3 chondrites : implications for early solar system processes

— The bulk compositions of the terrestrial planets are assessed. Venus and Earth probably have similar bulk compositions, but Mars is enriched in volatile elements. The inner planets are all depleted in volatile elements, as shown by K/U ratios, relative to most meteorites and the CI primordial values. Terrestrial upper mantle Mg/Si ratios are high compared with CI data. If they are representative of the bulk Earth, then the Earth accreted from a segregated suite of planetesimals that had non-chondritic major element abundances. The CI meteorite abundances, despite aqueous alteration, match the solar data and provide the best estimate for the composition of the solar nebula, including the iron abundance. The widespread depletion of volatile elements in the inner solar nebula is most likely caused by heating related to early violent solar activity (e.g., T Tauri and FU Orionis stages) which, for example, drove water out to a “snow line” in the vicinity of Jupiter. The variation in composition among the meteorites and the apparent lack of mixing among the groups indicates accretion from narrow feeding zones. There appears to have been little mixing between meteorite and planetary formation zones, as shown by the oxygen isotope variations, lack of mixing of meteorite groups, and differences in K/U ratios. In summary, it appears that the final accretion of planets did not result in widespread homogenization, and that mixing zones were not more than about 0.3 A.U. wide. Although the composition of the Moon is unique, and its origin due to an essentially random event, its presence reinforces the planetesimal hypothesis and the importance of stochastic processes during planetary accretion in the inner solar system.

Accretion in the inner nebula: The relationship between terrestrial planetary compositions and meteorites*

A search of active deflation basins near Jal, Lea County, New Mexico resulted in the discovery of two meteorites, Lea County 001 and 002. Lea County 001 has mean olivine and low-Ca pyroxene compositions of Fa(19) and Fs(17), respectively. These and all other mineralogical and petrological data collected indicate a classification of H5 for this stone. Lea County 002 has mean olivine and low-Ca pyroxene compositions of Fa(2) and Fs(4), and is unequilibrated. Although it is mineralogically most similar to Kakangari and chondritic clasts within Cumberland Falls, the high modal amount of forsterite makes Lea County a unique type 3 chondrite. Oxygen isotope data for Lea County 002 fall on an 0-16-mixing line through those of the enstatite meteorites and IAB irons, a feature shared by Kakangari.

Lea County 001, an H5 chondrite, and Lea County 002, an ungrouped type 3 chondrite

The Quest for Meteorites: Part One. Two New Meteorites from Deflation Surfaces in Lea County, New Mexico

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Roberta Score

Author Tools

Chat about Author

Papers

Lea County 001, an H5 chondrite, and Lea County 002, an ungrouped type 3 chondrite

The Quest for Meteorites: Part One. Two New Meteorites from Deflation Surfaces in Lea County, New Mexico