R

Earth sciences, geography, environment, planning.

RB

Earth sciences. Petroloby, meteorology…

RBGG

Petrology.

RBP

Meteorology & climatology.

RG

Geography. Coastal regions, exploration, cartography…

RGBP

Deltas, estuaries, coastal regions.

RGC

Human geography.

RGR

Geographical discovery & exploration.

RGV

Cartography, map-making & projections.