Oxygen isotope measurements have been used to study stony-iron meteorites before this research study. Why is this study different? On what basis do the authors argue that HEDs and mesosiderites come from the asteroid Vesta 4, but pallasites do not?

Geology Assignment

Read Greenwood, R. C., Franchi, I. A., Jambon, A., Barrat, J. A., & Burbine, T. H. (2006). Oxygen isotope variation in stony-iron meteorites. Science, 313(5794), 1763-1765, and answer the questions below in your own words.

1. Oxygen isotope measurements have been used to study stony-iron meteorites before this research study. Why is this study different? (4 points)

2. On what basis do the authors argue that HEDs and mesosiderites come from the asteroid Vesta 4, but pallasites do not? (6 points)

3. Some researchers disagree that HEDs and mesosiderites come from Vesta

4. What are their reasons, and how do Greenwood et al. (2006) counter these arguments? (8 points)

5. What are Vestoids, and what problem do they solve? (4 points)

6. What origin do the authors suggest for mesosiderites? (3 points)

7. What origin do the authors propose for pallasites? (3 points)