Cratère d’un volcan alien éteint aux parois abruptes de basalte

The mouth of a completely extinct volcano on an alien planet. An ancient volcano that has been inactive for millennia, cold and geologically dead. View from the edge of the crater. The first three hundred meters descend into a perfectly vertical gorge of cold, unstable, glassy black basalt, formed by ancient lava flows that have now completely solidified. No lava visible, no magma, no eruptive activity. The walls are dark, opaque, and shiny like cold obsidian, with dry fractures and mineral stratifications. Mineral dust suspended in the thin air of the alien planet. Silent, motionless atmosphere, pale alien sky with static clouds. A feeling of geological abandonment and absolute quiet. Ultra-detailed, photorealistic, realistic basalt textures, cold natural light, cinematic, 8K, high detail, depth of field.