The Genesis Apocryphon is a retelling of the stories of the patriarchs in an embellished fashion. It can be separated into books; the Book of Lamech, the Book of Noah and the Book of Abraham. The Genesis Apocryphon is largely based upon 1 Enoch, the Book of Jubilees and Genesis and therefore was most likely written after them. Most of the stories are told in first person, written in middle Aramaic, and based on biblical narratives but include other subjects and details previously unknown. Although the material is typically a free reworking of biblical material, occasionally there is word-for-word translation or paraphrasing from Genesis.
Source: Genesis Apocryphon – Wikipedia