Grupo al que pertenece el material geológico.

<xs:attribute name="group" default="G1_SOIL">
    <xs:annotation>
        <xs:documentation>Grupo al que pertenece el material geológico.</xs:documentation>
    </xs:annotation>
    <xs:simpleType>
        <xs:restriction base="xs:string">
            <xs:enumeration value="G0_VEGETAL_LAYER" />
            <xs:enumeration value="G1_SOIL" />
            <xs:enumeration value="G2_INTERMEDIATE" />
            <xs:enumeration value="G3_SHOFT_ROCK_NOT_CUT" />
            <xs:enumeration value="G3_SHOFT_ROCK_CUT" />
            <xs:enumeration value="G3_MEDIUM_ROCK_NOT_CUT" />
            <xs:enumeration value="G3_MEDIUM_ROCK_CUT" />
            <xs:enumeration value="G3_HARD_ROCK" />
            <xs:enumeration value="G3_VERY_HARD_ROCK" />
            <xs:enumeration value="G3_ROCK_NOT_EXPLODED" />
        </xs:restriction>
    </xs:simpleType>
</xs:attribute>