Purple sulfur bacteriaThe purple sulfur bacteria (PSB) are part of a group of Pseudomonadota capable of photosynthesis, collectively referred to as purple bacteria. They are anaerobic or microaerophilic, and are often found in stratified water environments including hot springs, stagnant water bodies, as well as microbial mats in intertidal zones. Unlike plants, algae, and cyanobacteria, purple sulfur bacteria do not use water as their reducing agent, and therefore do not produce oxygen.
Geothermal activityGeothermal activity is a group of natural heat transfer processes, occurring on Earth's surface, caused by the presence of excess heat in the subsurface of the affected area. Geothermal activity can manifest itself in a variety of different phenomena, including, among others, elevated surface temperatures, various forms of hydrothermal activity, and the presence of fumaroles that emit hot volcanic gases. Earth's internal heat budget Geothermal activity mostly appears in volcanic provinces, in some cases it can be caused by underground fires or by large deposits of radioactive elements.
HydrotherapyHydrotherapy, formerly called hydropathy and also called water cure, is a branch of alternative medicine (particularly naturopathy), occupational therapy, and physiotherapy, that involves the use of water for pain relief and treatment. The term encompasses a broad range of approaches and therapeutic methods that take advantage of the physical properties of water, such as temperature and pressure, to stimulate blood circulation, and treat the symptoms of certain diseases.
TravertineTravertine (ˈtrævərˌtiːn ) is a form of terrestrial limestone deposited around mineral springs, especially hot springs. It often has a fibrous or concentric appearance and exists in white, tan, cream-colored, and rusty varieties. It is formed by a process of rapid precipitation of calcium carbonate, often at the mouth of a hot spring or in a limestone cave. In the latter, it can form stalactites, stalagmites, and other speleothems. It is frequently used in Italy and elsewhere as a building material.
Earth's internal heat budgetEarth's internal heat budget is fundamental to the thermal history of the Earth. The flow of heat from Earth's interior to the surface is estimated at 47±2 terawatts (TW) and comes from two main sources in roughly equal amounts: the radiogenic heat produced by the radioactive decay of isotopes in the mantle and crust, and the primordial heat left over from the formation of Earth. Earth's internal heat travels along geothermal gradients and powers most geological processes.
Green sulfur bacteriaThe green sulfur bacteria, Chlorobiota, are a phylum of obligately anaerobic photoautotrophic bacteria that metabolize sulfur. Green sulfur bacteria are nonmotile (except Chloroherpeton thalassium, which may glide) and capable of anoxygenic photosynthesis. They live in anaerobic aquatic environments. In contrast to plants, green sulfur bacteria mainly use sulfide ions as electron donors. They are autotrophs that utilize the reverse tricarboxylic acid cycle to perform carbon fixation. They are also mixotrophs and reduce nitrogen.
PamukkalePamukkale, meaning "cotton castle" in Turkish, is a natural site in Denizli Province in southwestern Turkey. The area is famous for a carbonate mineral left by the flowing of thermal spring water. It is located in Turkey's Inner Aegean region, in the River Menderes valley, which has a temperate climate for most of the year. The ancient Greek city of Hierapolis was built on top of the travertine formation which is in total about long, wide and high. It can be seen from the hills on the opposite side of the valley in the town of Denizli, 20 km away.
