Bimmah Sinkhole in Arabic, and hence the name. To preserve the sinkhole, the local municipality developed a park, Hawiyat Najm Park (Haweat Najm Park), around it, along with a stairway leading down to the lake. The original cavern formed in the limestone of the Abat formation which lies below the more massive Seeb formation. When the cavern grew too large the rocks of the Seeb collapsed into it forming a sinkhole. It formed so close to the sea because of the increased subterranean water flow that occurred down-gradient. Bimmah Sinkhole Bimmah Sinkhole (Arabic هـويـة نـجـم "Hawaiyat Najm") is a water-filled depression, structurally
Danube Sinkhole other hand, to decide the smoldering controversy over the quantitative impact of the Danube sinkhole, which is known as the Danube Sinkhole case (). As the karst is developing, future sinkhole stretches cannot be accurately predicted. The underground river Danube annually removes about 7,000 tons of lime, that is 2,700 cubic meters, from the karst system. Future expansions or collapses in the underground system are conceivable, which would show above ground as sinkholes or ponors. In the long run, today's upper Danube will probably be redirected entirely into the Radolfzeller Aach, and thus to the Rhine. This would mean that