simulated lunar high land rocks using...

SIMULATED LUNAR HIGH LAND ROCKS USING JAPANESE IGNEOUS ROCKS H. Ii1 and H. Kanamori2, 1Wakayama University (930 Sakaedani, Wakayama city, Wakayama prefecture, Japan and hi-ro@center.wakayama-u.ac.jp), 2Japan Aerospace Exploration Agency (3-1-1 Yoshinodai,

Chuou-ku, Sagamihara city, Kanagawa prefecture, Japan and kanamori.hiroshi@jaxa.jp).

<Introduction:>3 major pristine igneous lunar highland rocks are 1) ferroan

anorthosites, 2) Mg-rich rocks, and 3) KREEP basalts. The

mixing ratios change according to lunar place. The simulated

rock was determined by mineralogy and main chemical

composition. Then, in order to make a simulated lunar

highland rock, the best method is to prepare each simulated

rock, the ferroan anorthosite, Mg-rich rocks, and KREEP rocks

and then mix them.

Table 1 Chemical composition (%) of Ferroan anorthositeand anorthite phenocryt in Miyakejima and Fugoppe

Anorthite Phenocryst

average values

Ferroan

Anorthosite

Miyakejima Fugoppe Mini Max

lava,

olivine

No

lava

SiO2 41.25 43.66 43.41 41.90 48.00

TiO2 0.03 n.d. 0.12 0.01 1.36

Al2O3 33.20 36.00 36.17 11.10 35.60

Fe2O3 2.83 0.70 0.56

FeO 0.72 0.43 n.d. 0.15 15.70

MnO 0.04 n.d. 0.01 0.00 0.24

MgO 3.59 0.17 0.09 0.14 10.10

CaO 18.34 19.38 19.27 13.00 20.40

Na2O 0.48 0.46 0.50 0.18 0.57

K2O 0.01 0.04 0.03 0.01 0.11

P2O5 0.00 n.d. 0.00 0.01 0.05

Table 2 chemistry of gabbroic rocks and

peridotite and Mg-rich rocks in Highland.

White

Gabbro

Green

Gabbro

Dunite Mg-rich rocks

In highland

Horoman area in

Hokkaido

Min Max

SiO2 46.27 41.31 41.20 37.50 52.00

TiO2 0.11 0.03 n.d. 0.03 1.03

Al2O3 27.83 14.69 1.31 1.30 28.70

Fe2O3 2.63 10.38 0.86

FeO 0.99 6.20 4.13 2.25 17.10

MnO 0.05 0.16 0.38 0.03 0.20

MgO 4.73 22.30 48.81 6.90 45.40

CaO 13.77 6.62 1.96 1.10 15.90

Na2O 2.69 1.11 n.d. 0.02 0.91

K2O 0.16 0.08 n.d. 0.00 0.23

P2O5 0.01 0.00 n.d. 0.03 0.11

Cr2O3 0.06 0.04 0.46 0.02 0.38

Table 3 Chemical composition of basalt

in Miyakejima and KREEP basalt

<Conclusion>Anorthite phenocrysts in Miyakejima and Fugoppe were simulated

as ferroan anorthosites. Ultrabasic rocks in Horoman were

simulated as Mg-rich rocks. Basalts in Miyakejima were simulated

as KREEP basalts. The simulated lunar highland rocks can be

made of a mixture of anorthite phenocrysts in Miyakejima and

Fugoppe, ultrabasic rocks in Horoman and basalts in Miyakejima.

<Ferroan anorthosites>High Ca feldspar, An content is 96 to 98% in Ferroan

anorthosite. Anorthite phenocryst in Miyakejima basalt lava

and volcanic bomb ranged from 95 to 98%. Olivine crystals

were included. Anorthite phenocryst in Fugoppe andesite tuff

ranged from 92 to 95% with pyroxene on the surface.

<Mg-rich rock>Mg-rich rock is not well defined

ranging from olivine-rich rocks

(dunite) all the way to rocks

composed of pyroxene and Na-

rich plagioclase (gabbro).

Fig.1 Location

<KREEP basalt>Volumetrically, KREEP

basalts are far less

important. Relatively Na

and SiO2 low and Mg

high to earth basalt.

Olivine in Miyakejima

anorthite can increase

Mg and decrease Na

content.

Pic.1 left : anorthite, volcanic bomb

right: anorthite phenocryst in lava

in Miyakejima

Pic.2 anorthite in

andesite tuff in Fugoppe

Pic.3 left: gabbro, right: dunite in Horoman

Basalt in Miyakejima KREEP basalts

Ako Benkene

misaki

Imasaki Min Max

SiO2 49.90 50.76 51.80 48.00 52.80

TiO2 1.14 1.23 1.42 1.03 2.23

Al2O3 15.63 15.55 14.51 13.30 16.40

Fe2O3 2.97 2.59 3.40

FeO 10.76 10.19 10.64 9.20 15.50

MnO 0.27 0.25 0.25 0.14 0.23

MgO 5.26 5.43 4.42 6.80 10.50

CaO 11.27 10.73 10.09 7.10 11.10

Na2O 2.04 2.16 2.42 0.29 0.89

K2O 0.24 0.38 0.42 0.25 0.67

P2O5 0.07 0.16 0.20 0.46 0.70