Basaltic meteorites
Abstract
The investigation of two groups of meteorites, igneous in origin, eucrites and shergottites, testify to the long history of volcanic activity in the solar system. Eucrites are texturally, mineralogically and chemically similar to terrestrial and lunar basaltic rocks but have also distinctions and have supposedly crystallized out of molten rock soon after the formation of the solar system, some 4.6 billion years ago. The examination of a reflectance spectrum of asteroids and meteorites has revealed that the only object in the solar system with a reflectance spectrum similar to that of the eucrites is Vesta, the second largest of the asteroids, with a diameter of about 550 km. Although agreement is not universal, it is probable that the eucrites are fragments of Vesta, or at least that lavas much like those from which the eucrites crystallized are present on the surface of the asteroid. The reflectance spectra of the shergottites do not match the spectra of any of the known asteroids. The shergottites are so similar to terrestrial basalts that the chemical composition of their source regions must be very similar to that of the earth's upper mantle. The age of the shergottites varies, 1.1 to .65 billion years, and one of the sources may be the giant volcanoes on the Martian surface.
- Publication:
-
Scientific American
- Pub Date:
- June 1980
- DOI:
- 10.1038/scientificamerican0680-54
- Bibcode:
- 1980SciAm.242f..54M
- Keywords:
-
- Basalt;
- Meteoritic Composition;
- Mineralogy;
- Stony Meteorites;
- Volcanology;
- Asteroids;
- Magma;
- Mars Surface;
- Planetary Craters;
- Planetary Evolution;
- Solar System;
- METEORITES;
- BASALTS;
- EUCRITES;
- SHERGOTTITES;
- VOLCANISM;
- COMPARISONS;
- PHOTOGRAPHS;
- EVOLUTION;
- VESTA ASTEROID;
- PYROXENES;
- CRYSTALS;
- SOILS;
- REFLECTIVITY;
- SPECTRUM;
- CONCENTRATION;
- ELEMENTS;
- MINERALS;
- MARS;
- SOLAR SYSTEM;
- MODELS;
- ORIGIN;
- VOLCANOES;
- PASAMONTE METEORITE;
- MAGMAS;
- TEXTURE;
- SHERGOTTY METEORITE;
- PARENT BODIES;
- Lunar and Planetary Exploration; Meteorites