(Qaaf) 50 : 7
وَالْأَرْضَ مَدَدْنَاهَا وَأَلْقَيْنَا فِيهَا رَوَاسِيَ وَأَنْبَتْنَا فِيهَا مِنْ كُلِّ زَوْجٍ بَهِيجٍ
And the earth, We have spread it wide, and We have set upon it mountains, and We have caused to bring forth in it every plants in beautiful pairs.
On the Day of Judgement, the setup of the universe at present will be completely altered in to another form as explained in verse 14: 48. On that Day Mountains will become cloud of dust, and the surface of the earth will become level, plain and smooth just like a single marble is spread out as told in verses 20: 105-107. See explanation 22: 5; 51: 48; and 84: 3-5.