Posted on Leave a comment

Systematics: Lunar Rock Classification

International Union of Geological Sciences
Subcommission on the Systematics of Igneous Rocks (2001)

I. SEDIMENTARY (Regolith)

II. METAMORPHIC

A. Shocked (monomict and polymict) rocks B. Impact (melt) breccias and glasses

III. IGNEOUS

A. Mare-type
1. Crystalline
a. Ti-poor basalt (<1.5 wt% TiO2) [formerly VLT]
b. Medium Ti basalt (1.5–6 wt% TiO2) [formerly low-Ti]
c. Ti-rich basalt (>6 wt% TiO2) [formerly high-Ti]
2. Glassy
a. Green
b. Yellow
c. Orange
d. Red
e. Black
B. Highland-type
1. Coarse-grained (>3 mm) [and transitional types]
a. Anorthosite
b. Norite
c. Gabbro
d. Troctolite
e. Dunite
2. Fine-grained (<3 mm)
a. Felsite
b. KREEP basalt
3. Fragmental (see II. above if metamorphic)

Leave a Reply