Guano deposit (Carlsbad Caverns, New Mexico, USA) : 無料・フリー素材/写真
Guano deposit (Carlsbad Caverns, New Mexico, USA) / James St. John
| ライセンス | クリエイティブ・コモンズ 表示 2.1 |
|---|---|
| 説明 | Guano deposit in Carlsbad Caverns, New Mexico, USA.---------------------Carlsbad Caverns (a.k.a. Carlsbad Cavern) in southeastern New Mexico, USA, is one of the world's most spectacular caves. The speleothem is abundant, large-scale, and magnificent. It has one of the largest cave rooms anywhere on Earth (the Big Room - 14 acres in size & a maximum height of 370 feet). The geologic origin of Carlsbad Caverns (& nearby Lechuguilla Cave) is unlike that of most caves. The cave is developed along the crest of Carlsbad Ridge, which is part of the prominent Guadalupe Escarpment, a long, northeast-to-southwest trending mountain range extending from southeastern New Mexico to western Texas.The natural entrance to Carlsbad Caverns was discovered in the late 1800s. Smoke was seen rising from the ridge at sunset. Close inspection revealed that the smoke was millions of bats flying from the mouth of a cave (www.nps.gov/cave/planyourvisit/images/bat_flight_hristov_...). The site was first called Bat Cave. The most common species is the relatively small Mexican freetail bat, Tadarida brasiliensis mexicana (Saussure, 1860). More than 8 million bats occupied the cave in early days, but the population is now down to an estimated 250,000-300,000 individuals.Thick guano deposits were found in the the Bat Cave portion of Carlsbad Caverns (east of & about 160 feet below the natural entrance). Because guano deposits are rich in phosphorus, they were mined from here in the early 1900s for use as fertilizer. Ancient lithified guano deposits are a variety of phosphorite, an uncommon sedimentary rock that is rich in phosphate.Locality: near Bottomless Pit, southern end of the Big Room, Carlsbad Caverns, southeastern New Mexico, USA |
| 撮影日 | 2015-07-30 09:43:23 |
| 撮影者 | James St. John |
| 撮影地 |
