Speleology

Plants and animals naturally live and grow in their natural habitat, which is a specific environment that provides the necessary resources for their survival, such as food, water, shelter, and space. Different species have evolved to thrive in specific habitats, like forests, deserts, grasslands, or oceans. These habitats support biodiversity and ecosystems.

They can feel quite cold in wamr weather and relatively warm in Winter - but most significant caves settle on the mean annual air temperature of the location in which they lie.

It's not an entirely hard-and-fast rule because individual caves are affected by their natural ventilation and the presence or not of streams, but it's a good guide.

Correct, in limestone including its meta-form marble, and gypsum; respectively calcium carbonate and calcium sulphate. The acidity comes from absorbed atmospheric carbon-dioxide.

NB though: Limestone is a rock anyway, but only these two calcium compound rocks are soluble to any real extent. Dolomite (magnesium carbonate based) will dissolve but the physical nature of its deposits tends to prevent cave formation.

Rainwater will also attack the felspar in granite but the process, hydrolysis, is extremely slow and does not lead to dissolutional caves in granite.

A Boulder, or Talus Cave rather stretches the definition of "cave", but it's simply a void or set of voids left between fallen boulders and their source rock-face.

A cave's chamber that is heavily obstructed or even terminated by collapsed rock is often called a "boulder chamber", but it's not correct to say that collapses form caves. They don't - they modify them.

Feldspar is a constituent of igneous rocks, primarily granite, and does not form rock masses alone. Also, although it does weather, very slowly, neither it nor the igneous rocks generally have the solubility of limestone.

Caves do form in granite etc by subaeriel, sea or riverine erosion, but they are generally small, shallow rock-shelters, not conduits as in limestone caves.

A Boulder, or Talus, Cave is simply an enterable void or set of voids between boulders and the rock-face from which they have fallen.

Collapses within existing karst, sea or lava caves may choke the passage or chamber with boulders, and such chambers are often called "boulder chambers", but that does not form the cave, and it is not the same as a true boulder cave.

Dissolution of the rock's primary ingredient, calcium carbonate, by water slightly acidified by absorbed atmospheric carbon-dioxide and percolating through the rock bulk's joints and other discontinuities. Eventually the network of initial tiny conduits will start to coalesce and capture, leading to discrete passages forming.

Yes, Earth's rotation can be affected by various factors such as the gravitational pull of the Moon and interactions with other celestial bodies. However, any change in Earth's rotation would happen over a long period of time and would have minimal impact on our daily lives.

Chemical weathering of limestone due to carbonic acid in water is the primary process that shapes Jenolan Caves. This results in the formation of intricate cave structures such as stalactites and stalagmites. Mechanical weathering, caused by physical forces like temperature changes, also plays a role in shaping the caves.

Yes, sea caves are typically formed through a combination of wave erosion and other erosive forces such as abrasion and corrosion. Breakers can play a role in this erosion process by wearing away at the rock along the coastline, ultimately leading to the formation of sea caves.

Formations that occur in caves include stalactites (hanging formations), stalagmites (rising formations), flowstones (sheet-like deposits), columns (stalactites and stalagmites joining), and helictites (twisted, branching formations). These formations are created by the slow deposition of minerals from dripping water over thousands of years.

This water is known as runoff, and it flows over the land surface and eventually into rivers, lakes, and oceans. Runoff plays a critical role in the water cycle by replenishing water sources and carrying sediment and nutrients to different ecosystems.

Karst topography may be found where groundwater erodes limestone to form valleys, sinkholes, and caverns. The result is a landscape characterized by underground drainage systems with sinkholes serving as natural funnels for groundwater to flow into caverns. Over time, this process creates unique landforms such as caves and disappearing streams.

Principally, as by far the majority of the world's caves are formed in limestone uplands, by dissolution of the rock's calcium carbonate by slightly acid rain-water seeping through the joints and bedding-planes. These, and other discontinuities such as faults and shale bands, provide a "leak path" for the initial penetration of water into the rock mass, though the water also has to find an outlet at a lower altitude from the inlet for flow to take place.

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In time the water forms discrete conduits along the joints etc through the rock, and these coalesce to develop passages and chambers. The passages will continue to develop as long as they carry their streams.

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This can happen only in soluble rocks: limestone and gypsum. Caves in other, insoluble, rocks are developed by other mechanisms.

Sinkholes and caverns are formed from carbolic acid. This carbolic acid dissolves rock which creates the spaces that form the sinkholes and caverns. The carbolic acid is created when carbon dioxide dissolves in water.

Tufa forms when calcium-rich groundwater interacts with carbonate minerals in the Earth's crust, causing calcium carbonate to precipitate out of the water and accumulate over time. This process typically occurs in areas with limestone bedrock or where calcium-rich water emerges from springs or seeps.

Caverns can form in the zone of saturation due to processes such as dissolution, where groundwater dissolves soluble rock (like limestone) to create underground voids. Over time, these voids can enlarge and form caverns as groundwater continues to flow through and erode the rock. Additional factors like the presence of fractures or fault lines can also contribute to cavern formation in the zone of saturation.

Caverns are typically formed through the process of erosion, where water dissolves and carves out rock formations such as limestone over a long period of time. Other factors like tectonic activity or the collapse of underground caves can also create caverns.

How Caves Form in Limestone

That is such a common question on ‘Answers’ I wrote this single reply! The technical terms are introduced by capital initials.

Most of the world’s caves are in Limestone.

Caves need three materials: a soluble rock like Limestone or Gypsum, water and Carbon-dioxide (CO2).

Their host limestone also needs to be of appropriate physical structure and raised into hills, then subjected to reasonably consistent precipitation for many tens or hundreds of thousands of years.

Limestone is a sedimentary rock of which the world’s greater proportion was laid down in warm, relatively shallow, seas. The rock was laid in horizontal layers – Beds – separated by Bedding-planes which generally reflect geologically-brief changes in the environment. The suite of beds is known as a Formation, generally named after its “type area”.

Later continental uplift (tectonic processes) raise the formation along with its underlying rocks, usually tilting and folding it to at least some extent in the process. Since most rocks are brittle they cannot take much stress, and limestone beds crack into grids of fine fractures called Joints. The uplift and folding often also causes Faulting – major breaks with the rock mass one side of the Fault Plane being raised, lowered or moved horizontally past that on the opposite side. (Note: Plane – the “Fault Line” sometimes misused as a political metaphor is that of the fault-plane cutting the land surface.)

Now we have the hills, next we need rain-water that has absorbed atmospheric CO2 to create Carbonic Acid (weak, natural soda water in fact!). It may be augmented by acids from the soil, too. This solvent permeates through all those joints, bedding-planes and faults; flowing very, very slowly under considerable pressure applied by its depth, from its sinks on the surface to its springs at the base of the formation. In doing so, it dissolves the limestone (chemical weathering), creating meshes of tiny micro-conduits that over many tens of thousands of years coalesce and capture each other to form cave passages.

Once this happens, the rate of erosion can increase – though still to perhaps only a few millimetres per thousand years under generally temperate climates.

A cave, or a series within a cave system, that still carries its formative stream is called “Active”, and is still being developed.

Surface changes such as the valley floor being lowered by erosion, or down-cutting within the cave by its stream, changes the water’s route and the original, now dried-out, stream-way is called “Fossil” or “Abandoned”. Such passages may be filled with silt left by floods as the main flow gradually abandons them; or may become richly decorated with Speleothems – calcite deposits such as stalactites and stalagmites precipitated from ground-water still oozing through the joints in the limestone above the cave. In time such passages may start to break down as there is no stream to dissolve away slabs falling from the roof as permeating ground-water attacks the rock above.

In the end, surface lowering of the landscape as a whole, breaches and destroys the cave. Nothing is permanent in Nature!

Caves in limestone are also parts of Karst Landscape. i.e. a landscape developed by the dissolution of limestone, giving surface features like Dolines, Limestone Pavement, and in the tropics, distinctive hills such as those represented in Chinese Willow-pattern images. ‘Karst’ is from the Slavic word ‘Kras’, the name for its world type-area.

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The above is purely an introduction to a vastly more complex and subtle series of processes, of course, and you need to refer to appropriate text-books on geology and cave studies to learn them.

The scientific study of caves is Speleology – embracing geology, hydrology, biology, archaeology and other disciplines.

Simply visiting caves to enjoy them for their scenery and the physical and mental challenges they present, is called Caving, though you can’t study a cave unless you can negotiate its obstacles. The enthusiasts are simply Cavers throughout the English-speaking world – you see “spelunkers” sometimes on ‘Answers’ but it's an old slang word not found in caving literature.

In the ocean, energy is transferred through processes like conduction, convection, and radiation. Solar radiation warms the surface of the ocean, creating temperature gradients that drive energy transfer. In the atmosphere, energy is primarily transferred through convection, where warm air rises and cold air sinks, creating wind patterns and weather systems.

Underground caves are primarily formed by the dissolution of limestone and other soluble rocks by groundwater. This process, known as karstification, is influenced by chemical reactions between the water and the rock, as well as physical erosion caused by the flowing water. Over time, these processes create the intricate cave systems that we see underground.

Yes, caves can form on mountains through various geological processes such as erosion, tectonic activity, and chemical weathering. They can be created by the dissolution of limestone rock, the collapse of volcanic tubes, or the shifting of fault lines over time. Mountain caves can be found at various elevations, providing unique habitats for diverse flora and fauna.

Caves that go straight down are typically referred to as vertical caves or potholes. These caves are formed by a combination of geological processes such as water erosion or volcanic activity, creating deep vertical shafts in the ground.

Caldera - if the collapse is into a volcanoe's magma chamber.

If into a limestone cave its is a shake-hole or sink-hole. (I think that may be a US / UK respectively, name division for the same feature.)

The stuff that grows on rocks in caves is typically referred to as cave formations or speleothems. These formations can include stalactites, stalagmites, columns, draperies, and flowstones, which are created by minerals precipitating out of water dripping or flowing in the cave.