Basin Groups

Basin Groups refers to 9 subdivisions of the lunar Pre-Nectarian geologic period. It is the second era of the Hadean

Read more about Basin Groups:  Definition, Relationship To Earth's Geologic Time Scale

Famous quotes containing the word groups:

    Under weak government, in a wide, thinly populated country, in the struggle against the raw natural environment and with the free play of economic forces, unified social groups become the transmitters of culture.
    Johan Huizinga (1872–1945)