from The Century Dictionary.
- Having the peculiar granulated structure characteristic of chondrite.
from the GNU version of the Collaborative International Dictionary of English.
- adjective (Min.) Granular; pertaining to, or having the granular structure characteristic of, the class of meteorites called chondrites.
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- adjective geology Of or pertaining to a
- adjective planetology, of an elemental ratio Similar to that found in
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adjective having a granular structure like that of chondrites
from Wiktionary, Creative Commons Attribution/Share-Alike License
These geochemical signatures can be compared with what are called "chondritic" meteorites: primitive meteorites that have fallen to Earth in modern times, but have never undergone any sort of metal segregation.
Until recently, researchers generally thought that the Earth and the other planets of the solar system were chondritic, meaning that the mantle's chemistry was thought to be similar to that of chondrites -- some of the oldest, most primitive objects in the solar system.
The problem is that all those bits of iron, and loose chondritic regolith that are attracted to the magnetic field will pull loose from the asteroid and clump to the magnet.
This resulted in geochemists realizing that the Earth, the Moon, and Mars all have lithic compositions that contain anywhere from five to eight percent more neodymium and samarium than the chondritic meteorites do.
Given the fact that chondritic meteorites -- meteorites containing chondrules -- have a similar chemical make-up to that of our Sun, it has been taken as a given that we can figure out what the solar nebula was made of, as the Earth coalesced into being from out of it.
The basis many geologists use for dating the Earth rests on the assumption that chondritic meteorites are very representative of a “bulk Earth composition”, the composition of the early Earth.
Circling Alpha Centauri A near the middle of those asteroids called the Serpent Swarm, it was originally a chondritic body with a sideritic component giving it more structural strength than is usual for that kind.
One possibility, according to Jackson, is that "the early Earth went through a differentiation event and the Earth's crust was extracted from the early mantle and is now hidden in the deep earth; the hidden crust and the mantle found on Baffin Island would sum to chondritic."
This study challenges the idea that the Earth has a chondritic primitive mantle and according to Matthew Jackson is, "suggesting an alternative."
The model that the Earth was chondritic was called into question with a discovery five years ago by a team at the Carnegie Institution of Washington, which suggested the ratio of neodymium on Earth was higher than what would be expected if the Earth were indeed chondritic.