Enoch sees the holy mountain of God, Jerusalem in the center of the earth, and the surrounding geography — a blessed land with deep valleys and flowing streams, including the accursed valley.
Jerusalem as the center of the earth reflects a well-established biblical and ancient Near Eastern concept (Ezekiel 5:5, 38:12). The 'accursed valley' is likely the Valley of Hinnom (Gehenna), which became the standard image for judgment and hell.
The idealized geography blends real topography (valleys around Jerusalem) with theological symbolism.
Ezekiel 5:5 (Jerusalem in the center of the nations); Ezekiel 38:12 (navel of the earth); Jeremiah 7:31-32 (Valley of Hinnom as place of judgment); Matthew 5:22 (Gehenna).
Ge'ez text per Charles/Knibb editions
I traveled from there to the center of the earth and saw a blessed place where trees with flourishing branches were growing.
REF And I went from thence to the middle of the earth, and I saw a blessed place in which there were trees with branches abiding and blooming [of a dismembered tree].
Ge'ez text per Charles/Knibb editions
There I saw a holy mountain, and beneath it to the east a stream flowed southward.
REF And there I saw a holy mountain, and underneath the mountain to the east there was a stream and it flowed towards the south.
Ge'ez text per Charles/Knibb editions
To the east I saw another mountain, higher than the first, and between them a deep, narrow ravine with a stream running through it beneath the mountain.
REF And I saw towards the east another mountain higher than this, and between them a deep and narrow ravine: in it also ran a stream underneath the mountain.
Ge'ez text per Charles/Knibb editions
To the west there was another mountain, lower and less elevated than the first, with a deep dry ravine between them. Another deep, dry ravine lay at the edges of the three mountains.
REF And to the west thereof there was another mountain, lower than the former and of small elevation, and a ravine deep and dry between them: and another deep and dry ravine was at the extremities of the three mountains.
Ge'ez text per Charles/Knibb editions
All the ravines were deep and narrow, cut from hard rock, and no trees were planted in them.
REF And all the ravines were deep and narrow, (being formed) of hard rock, and trees were not planted upon them.
Ge'ez text per Charles/Knibb editions
I marveled at the rocks and at the ravine — I marveled greatly.
REF And I marvelled at the rocks, and I marvelled at the ravine, yea, I marvelled very much.