Sinkhole may exhibit a visible opening into a cave below. In the case of exceptionally large sinkholes, such as the Minyé sinkhole in Papua New Guinea or Cedar Sink at Mammoth Cave National Park in Kentucky, an underground stream or river may be visible across its bottom flowing from one side to the other. Sinkholes are common where the rock below the land surface is limestone or other carbonate rock, salt beds, or in other soluble rocks, such as gypsum, that can be dissolved naturally by circulating ground water. Sinkholes also occur in sandstone and quartzite terrains. As the rock dissolves,
Close to a World Below Close to a World Below Close to a World Below is the fourth album by Immolation. It was released on Metal Blade Records in 2000. Since its release, "Close to a World Below" has received universal acclaim. Todd Nief of AllMusic gave the "Close to a World Below" four and a half stars, calling the album a late-career classic. He stated that with "Close to a World Below", Immolation released one of the most profound and creative death metal albums of the 2000s which gave a new voice to a genre deluged with cookie-cutter clones. Metal Storm gave "Close to