Early differentiation of magmatic iron meteorite parent bodies from Mn–Cr chronometry

The early formation of the IVA iron meteorite parent body

Hf-W Chronometry for an Early Differentiation in the Parent Body of Ureilites

Ureilites are primitive achondrites that are composed mainly of olivine and pyroxenes with abundant interstitial and crosscutting carbon polymorphs, Fe-Ni metal, sulfides, and silicates. Studies of ureilites indicate that the parent body went through a series of igneous processes, while, at the same time, ureilites contain features that can only be explained by mixing of primitive nebular mater...

Ar-ar Dating of Thermal Events on Meteorite Parent Bodies

Parent bodies of meteorites have experienced a variety of thermal events caused by early internal metamorphism and impact heating. Among radiometric chronometers, the 39 Ar-40 Ar technique is particularly sensitive to such thermal events. For over two decades the JSC laboratory has acquired 39 Ar-40 Ar data on a wide variety of meteorite types. The purpose here is to summarize some JSC data (an...

Differentiation of Metal-rich Meteoritic Parent Bodies

Introduction: There is now increasing evidence that the timescale between the formation of CAIs and of chondrules is < 1-2 Ma, and that the achondritic parent planets may have formed and differentiated within 2-4 Ma of the origin of the Solar System [1,2]. Long-lived chronometers (such as 187 Re

A Non-magmatic Iron Meteorite as Impactor for the Rochechouart Crater

The Rochechouart impact crater in the French Massif Central, has a diameter of 20 25 km [1] and an age of 250 my [2]. The cater is deeply eroded, down to the crater floor. Impact melt outcrops can be found in different parts of the crater [3]. The type of impactor that produced Rochechouart crater is still not clear. The first proposal of an IIA iron asteroid was based on the abundance of some ...