English to Spanish Science Geology Vulcanology, Archaeology,

Me ayudan cual es el significado de "undercut" "Undercutting" y "roughed out" (these moai, statues in Easter Island are in the quarry in which they were carved and are found in different degrees of completion- intact but not finished)

"Moai 6 t0 11 are in similar stages of completion. Moai 6 is undercut on the right side. Moai 7 is attached at the head but it is partially undercut at the east side. In order to determine their states of production and other details, we excavated moai 8 and 9. Moai 8 is supine, head down and still fully attached to bedrock. The top of the head is roughed out in a rectilinear fashion. No hands are carved. The entire above ground portion of the statue surface is badly eroded, the stone is overall pulverized and black-gray in color. The base of the Moai 8 is nearly touchig the base of the attached statue 6 above it. The bases of both statues are angled and cut to accomodate the position of each statue relative to the other. Moai 9 is a complete statue. Moai 10 is the largest of the unfinished statues. The rounding undercutting on Moai 11 is 47 cm deep, making this statue nearly ready for removal. It is so badly damaged on the ventral side, that it is impossible to say if designs are present. It is the undercut area beneath Moai 11 that is embellished with two of the petroglyph motifs."

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