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All About Speleology & Stratigraphy

VSAT 2023

What is Speleology?

Last updated date: 30th Jan 2023
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The scientific study of caves and other karst features, including their make-up, structure, physical qualities, history, life forms, and the processes by which they form (speleogenesis) and change over time, is known as speleology (speleomorphology). The leisure pastime of exploring caves is occasionally referred to as speleology, but it is more appropriately known as caving, potholing (British English), or spelunking. Because the physical abilities required for in situ investigation are similar, speleology and caving are frequently linked.


Speleology is a multidisciplinary field that combines chemistry, biology, geology, physics, meteorology, and cartography knowledge to create representations of caves as dynamic, evolving systems.


History

In the 1680s, John Beaumont wrote extensive descriptions of some Mendip caves, long before modern speleology was formed.


Cave studies were regarded as part of the larger disciplines of geography, geology, or archaeology prior to the mid-nineteenth century, and their scientific significance was only judged in terms of their contribution to other branches of study. Prior to the efforts of Édouard-Alfred Martel (1859–1938), the 'father of modern speleology,' who popularized the concept of speleology as a unique field of study in France through his vast and well-publicized cave excursions, very little cave-specific research was done. Martel formed the Société de Spéléologie, the world's first cave research organisation, in 1895. Herbert E. Balch was another early speleologist.


In 1949, at a meeting in Valence-sur-Rhone, France, an international speleological congress was proposed, and the first one was held in Paris in 1953. In 1965, the International Union of Speleology (UIS) was established.


Because of the increased public interest and awareness, as well as the fact that most speleological fieldwork has been done by sport cavers, the expansion of speleology is inextricably related to the growth of caving as a sport.


Speleology Hydrology

A karst landscape is one in which the limestone beneath the surface has been degraded. The bulk of the time, caves are generated through chemical corrosion and dissolution. Corrosion can occur in a variety of ways, including chemical reactions in carbonate rocks, physical reactions in gypsum and rock salt, and material degradation in silicate rocks and warm climates.


Cave Cartography

One of the most regular technical activities in a cave is the production of an exact, detailed map. Cave maps, also known as surveys, can be used to compare caves by length, depth, and volume, as well as provide speleogenesis clues, serve as a geographical reference for further scientific study, and aid tourists with route-finding.


Cave Biology

Caves are home to a diverse range of biota. Cave ecologies are quite diverse, and they are not easily distinguished from those found on the surface. However, the ecosystem grows more rarefied as the cave gets deeper.


There are three types of cave habitats to consider:

  1. Endogean: Cave sections that communicate with surface soils via fissures and rock seams, groundwater seepage, and root protrusion.

  2. Parahypogean: the areas near cave openings that stretch till the last rays of sunshine penetrate.

  3. Hypogean: or "real" cave settings. These can have regular interaction with the surface, such as through wind and underground rivers, or through animal migration, or they can be virtually completely isolated. Deep hypogean environments can support independent ecologies whose principal source of energy is chemical energy released by chemoautotrophic bacteria from limestone and other rocks.

Cave Organisms

There are three types of cave organisms:

  1. Troglobites (Cave Dwellers): are cave-specific cavernicoles that must be present. Some animals may leave caves for brief periods of time and complete parts of their life cycles above ground, but they cannot live their entire lives outside of one. Chemotrophic bacteria, several flatworm species, glowworms, collembola, and blindfish are examples.

  2. Troglophiles (Cave Lovers): They can live in caves for part or all of their lives, but they can also finish their life cycle in suitable settings on the surface. Cave crickets, bats, millipedes, pseudoscorpions, and spiders are examples.

  3. Trogloxenes (Cave Guests): It frequents caves and may require caverns for part of its life cycle, but it must return to the surface (or a parahypogean zone) for at least part of its life cycle. The most well-known examples are hibernating reptiles and mammals.

Stratigraphy Geology

The meaning, history as well as types of stratigraphy are given below:


Stratigraphy Meaning

Upon being asked the Stratigraphy meaning, we can say that it is the study of rock layers (strata) and layering is the subject of stratigraphy, a branch of geology (stratification). It's mostly used to look at sedimentary and layered volcanic rocks. Lithostratigraphy (lithologic stratigraphy) and biostratigraphy are two related subfields of stratigraphy (biologic stratigraphy).


Historical Development

In a 1669 book on the fossilisation of organic remains in sediment layers, Catholic priest Nicholas Steno developed the law of superposition, the notion of original horizontality, and the idea of lateral continuity, laying the theoretical foundation for stratigraphy.


William Smith applied stratigraphy on a broad scale for the first time in the 1790s and early 1800s. Smith, known as the "Father of English Geology," understood the value of strata, or rock stacking, and fossil markers for connecting strata, and he constructed the first geologic map of England. Georges Cuvier and Alexandre Brongniart, who investigated the geology of the Paris region in the early nineteenth century, were also prominent users of stratigraphy.


Types of Stratigraphy

  1. Lithostratigraphy 

Physical differences in rock type cause variation in rock units, which is most visibly represented as visible layering (lithology). This variation can occur vertically (bedding) or laterally (layering), and it reflects differences in deposition conditions (known as facies change). The lithostratigraphy, or lithologic stratigraphy, of the rock unit, is determined by these variances. Understanding how specific geometric relationships between rock strata originate and what these geometries imply about their initial depositional environment are key ideas in stratigraphy. The law of superposition, a fundamental principle in stratigraphy, asserts that the oldest strata appear at the bottom of an undamaged stratigraphic series.


Chemostratigraphy is the study of changes in trace elements and isotope ratios within and between lithologic units. Carbon and oxygen isotope ratios shift over time, allowing researchers to track tiny changes in the paleoenvironment. Isotopic stratigraphy became a specialised area as a result of this.

The cyclic changes in the relative proportions of minerals (especially carbonates), grain size, the thickness of sediment layers (varves), and fossil variety across time, as a result of seasonal or longer-term changes in palaeoclimates, are documented by cyclostratigraphy.

  1. Biostratigraphy
    Biostratigraphy, also known as paleontologic stratigraphy, is based on the presence of fossils in rock layers. Correlation in time is stated to exist across strata from different sites that contain the same fossil fauna and flora. The notion of faunal succession, developed by William Smith, predated biological evolution and was one of the first and most compelling lines of evidence for it. It offers compelling evidence for the emergence (speciation) and extinction of species. Based on the evidence of biologic stratigraphy and faunal succession, the geologic time scale was constructed in the nineteenth century. Until the invention of radiometric dating, which was based on an absolute time framework, leading to the establishment of chronostratigraphy, this timeline remained a relative scale.


The Vail curve, which aims to establish a global historical sea-level curve based on inferences from worldwide stratigraphic patterns, is a significant development. Petroleum geologists employ stratigraphy to define the nature and extent of hydrocarbon-bearing reservoir rocks, seals, and traps.

  1. Chronostratigraphy

Chronostratigraphy is a branch of stratigraphy that assigns an absolute age to rock layers rather than a relative age. The branch is concerned with directly and inferentially deriving geochronological data for rock units in order to determine a sequence of time-relative events that formed the rocks formation. The ultimate goal of chronostratigraphy is to assign dates to the sequence of deposition of all rocks within a geological region, then to all geological regions, and finally to the entire Earth.


A stratigraphic hiatus is a gap or missing layer in an area's geological record. This could be the result of a pause in sediment deposition. Alternatively, the gap could be due to erosion, in which case it's known as a stratigraphic vacuity. Because the deposition was put on hold for a while, it's called a hiatus. A physical gap can be interpreted as a time of non-deposition as well as deterioration. The appearance of a pause might be caused by a geologic fault.

  1. Magnetostratigraphy: The method of magnetostratigraphy is used to date sedimentary and volcanic sequences. The approach collects oriented samples at predetermined intervals over a region. The materials are examined to identify their detrital remanent magnetism (DRM), or the polarity of the Earth's magnetic field at the time of deposit. This is conceivable in sedimentary rocks because very fine-grained magnetic minerals (17 m) behave like small compasses as they fall through the water column, orienting themselves with Earth's magnetic field. That orientation is kept after the body is buried. Magnetic minerals that form in the melt of volcanic rocks align themselves with the ambient magnetic field and are set in place when the lava crystallises.

Conclusion

Therefore, Speleology is said to be known as a scientific system which is concerned with the caves. Exploration as well as description and defining the characteristics of caves etc. are said to be the key focus of this discipline. Besides these, it also focuses on the caves development and formation. It also requires geological as well as hydrological knowledge in order to accomplish the goals of the discipline. On the other hand, if we look at stratigraphy, it is also one of the important branches of Geology that deals with the different stratas of the rocks and helps in getting essential information from the rocks.

FAQs on All About Speleology & Stratigraphy

1. What is the Longest Cave System in the World?

The world's longest known cave system is preserved in Mammoth Cave National Park. Mammoth Cave is a limestone labyrinth that has been explored for more than 400 miles, with another 600 miles estimated by the park.

2. What is the Fundamental Principle of Stratigraphy?

The sedimentary strata are stated to be deposited in layers, with the older on the bottom and the new on top, according to the "principle of superposition.”

3. What do you mean by Biostratigraphy?

It refers to the presence of fossils in layers of the rocks. It gives information about the existence as well as extinction of the various species through the rock layers and their fossils. It is also known as paleontological stratigraphy. 

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