Teri (geology)

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Geological map of southeastern India showing teri zone (marked in blue caret patterning) Teris.jpg
Geological map of southeastern India showing teri zone (marked in blue caret patterning)

Teri or Teri dune complex is a coastal landscape peculiar to some parts of Tamil Nadu mainly in southeastern India. The landscape consists of sediments dating to the Quaternary Period and made of marine deposits with aeolianite and characteristic red sand and silt dunes. These red soils are thought to have originated in the Pleistocene. [1] Robert Bruce Foote hypothesized that these dunes were created by the action of winds (aeolian) lifting the fine silt fraction from further east. [2] These dunes are oriented along the axis running parallel to the coast and between the latitudes of 8°00′ to 9°30′ N and longitudes 77°18′ to 79°00′ E. The soils also have calcium deposits replacing the old roots of vegetation. [3] The soil is rich in ilmenite and the red colour is derived from haematite originating from garnet. [4] [5] [6]

Related Research Articles

<span class="mw-page-title-main">Dune</span> Hill of loose sand built by aeolian processes or the flow of water

A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat regions covered with wind-swept sand or dunes with little or no vegetation are called ergs or sand seas. Dunes occur in different shapes and sizes, but most kinds of dunes are longer on the stoss (upflow) side, where the sand is pushed up the dune, and have a shorter slip face in the lee side. The valley or trough between dunes is called a dune slack.

<span class="mw-page-title-main">Gypsum</span> Soft calcium sulfate mineral

Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, drywall and blackboard or sidewalk chalk. Gypsum also crystallizes as translucent crystals of selenite. It forms as an evaporite mineral and as a hydration product of anhydrite. The Mohs scale of mineral hardness defines gypsum as hardness value 2 based on scratch hardness comparison.

<span class="mw-page-title-main">Geography of India</span>

India is situated north of the equator between 8°4' north to 37°6' north latitude and 68°7' east to 97°25' east longitude. It is the seventh-largest country in the world, with a total area of 3,287,263 square kilometres (1,269,219 sq mi). India measures 3,214 km (1,997 mi) from north to south and 2,933 km (1,822 mi) from east to west. It has a land frontier of 15,200 km (9,445 mi) and a coastline of 7,516.6 km (4,671 mi).

<span class="mw-page-title-main">Marl</span> Lime-rich mud or mudstone which contains variable amounts of clays and silt

Marl is an earthy material rich in carbonate minerals, clays, and silt. When hardened into rock, this becomes marlstone. It is formed in marine or freshwater environments, often through the activities of algae.

<span class="mw-page-title-main">Sediment</span> Particulate solid matter that is deposited on the surface of land

Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand and silt can be carried in suspension in river water and on reaching the sea bed deposited by sedimentation; if buried, they may eventually become sandstone and siltstone through lithification.

<span class="mw-page-title-main">Geomorphology</span> Scientific study of landforms

Geomorphology is the scientific study of the origin and evolution of topographic and bathymetric features generated by physical, chemical or biological processes operating at or near Earth's surface. Geomorphologists seek to understand why landscapes look the way they do, to understand landform and terrain history and dynamics and to predict changes through a combination of field observations, physical experiments and numerical modeling. Geomorphologists work within disciplines such as physical geography, geology, geodesy, engineering geology, archaeology, climatology, and geotechnical engineering. This broad base of interests contributes to many research styles and interests within the field.

<span class="mw-page-title-main">Silt</span> Classification of soil or sediment

Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. Silt may occur as a soil or as sediment mixed in suspension with water. Silt usually has a floury feel when dry, and lacks plasticity when wet. Silt also can be felt by the tongue as granular when placed on the front teeth.

<span class="mw-page-title-main">Loess</span> Sediment of accumulated wind-blown dust

A loess is a clastic, predominantly silt-sized sediment that is formed by the accumulation of wind-blown dust. Ten percent of Earth's land area is covered by loesses or similar deposits.

<span class="mw-page-title-main">Shoal</span> Natural submerged sandbank that rises from a body of water to near the surface

In oceanography, geomorphology, and geoscience, a shoal is a natural submerged ridge, bank, or bar that consists of, or is covered by, sand or other unconsolidated material and rises from the bed of a body of water to close or above the surface that poses a danger to navigation. Shoals are also known as sandbanks, sandbars, or gravelbars. Two or more shoals that are either separated by shared troughs or interconnected by past or present sedimentary and hydrographic processes are referred to as a shoal complex.

<span class="mw-page-title-main">Barrier island</span> Coastal dune landform that forms by wave and tidal action parallel to the mainland coast

Barrier islands are a coastal landforms—a type of dune system and sand island—where an area of sand has been formed by wave and tidal action parallel to the mainland coast. They usually occur in chains, consisting of anything from a few islands to more than a dozen. They are subject to change during storms and other action, but absorb energy and protect the coastlines and create areas of protected waters where wetlands may flourish. A barrier chain may extend for hundreds of kilometers, with islands periodically separated by tidal inlets. The largest barrier island in the world is Padre Island of Texas, United States, at 113 miles (182 km) long. Sometimes an important inlet may close permanently, transforming an island into a peninsula, thus creating a barrier peninsula, often including a beach, barrier beach. Though many are long and narrow, the length and width of barriers and overall morphology of barrier coasts are related to parameters including tidal range, wave energy, sediment supply, sea-level trends, and basement controls. The amount of vegetation on the barrier has a large impact on the height and evolution of the island.

<span class="mw-page-title-main">Deposition (geology)</span> Geological process in which sediments, soil and rocks are added to a landform or landmass

Deposition is the geological process in which sediments, soil and rocks are added to a landform or landmass. Wind, ice, water, and gravity transport previously weathered surface material, which, at the loss of enough kinetic energy in the fluid, is deposited, building up layers of sediment.

<span class="mw-page-title-main">Siltstone</span> Sedimentary rock which has a grain size in the silt range

Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt. It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility.

<span class="mw-page-title-main">Aeolian processes</span> Processes due to wind activity

Aeolian processes, also spelled eolian, pertain to wind activity in the study of geology and weather and specifically to the wind's ability to shape the surface of the Earth. Winds may erode, transport, and deposit materials and are effective agents in regions with sparse vegetation, a lack of soil moisture and a large supply of unconsolidated sediments. Although water is a much more powerful eroding force than wind, aeolian processes are important in arid environments such as deserts.

<span class="mw-page-title-main">Geological hazard</span> Geological state that may lead to widespread damage or risk

A geologic hazard or geohazard is an adverse of geologic condition capable of causing widespread damage or loss of property and life. These hazards are geological and environmental conditions and involve long-term or short-term geological processes. Geohazards can be relatively small features, but they can also attain huge dimensions and affect local and regional socio-economics to a large extent.

<span class="mw-page-title-main">Caliche</span> Calcium carbonate based concretion of sediment

Caliche is a sedimentary rock, a hardened natural cement of calcium carbonate that binds other materials—such as gravel, sand, clay, and silt. It occurs worldwide, in aridisol and mollisol soil orders—generally in arid or semiarid regions, including in central and western Australia, in the Kalahari Desert, in the High Plains of the western United States, in the Sonoran Desert, Chihuahuan Desert and Mojave Desert of North America, and in eastern Saudi Arabia at Al-Hasa. Caliche is also known as calcrete or kankar. It belongs to the duricrusts. The term caliche is borrowed from Spanish and is originally from the Latin word calx, meaning lime.

<span class="mw-page-title-main">Ramanathapuram district</span> District of Tamil Nadu in India

Ramanathapuram District, also known as Ramnad District, is one of the 38 districts an administrative districts of Tamil Nadu state in southern India. The old Ramanathapuram District consists of Present day Virudhunagar and Sivagangai districts, it touches the Western ghats and bordered with the state of Kerala and east by Bay of Bengal. It was the largest district on that time. The town of Ramanathapuram is the district headquarters. Ramanthapuram District has an area of 4,123 km2. It is bounded on the north by Sivaganga District, on the northeast by Pudukkottai District, on the east by the Palk Strait, on the south by the Gulf of Mannar, on the west by Thoothukudi District, and on the northwest by Virudhunagar District. The district contains the Pamban Bridge, an east–west chain of low islands and shallow reefs that extend between India and the island nation of Sri Lanka, and separate the Palk Strait from the Gulf of Mannar. The Palk Strait is navigable only by shallow-draft vessels. As of 2011, Ramanathapuram district had a population of 1,353,445 with a sex-ratio of 983 females for every 1,000 males. The district is home to the pilgrimage center of Rameswaram.

<span class="mw-page-title-main">Abrasion (geology)</span> Process of erosion

Abrasion is a process of erosion which occurs when material being transported wears away at a surface over time. It is the process of friction caused by scuffing, scratching, wearing down, marring, and rubbing away of materials. The intensity of abrasion depends on the hardness, concentration, velocity and mass of the moving particles. Abrasion generally occurs in four ways: glaciation slowly grinds rocks picked up by ice against rock surfaces; solid objects transported in river channels make abrasive surface contact with the bed and walls; objects transported in waves breaking on coastlines; and by wind transporting sand or small stones against surface rocks.

<span class="mw-page-title-main">Sand</span> Granular material composed of finely divided rock and mineral particles

Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of soil or soil type; i.e., a soil containing more than 85 percent sand-sized particles by mass.

<span class="mw-page-title-main">Backswamp</span> Environment on a floodplain where deposits settle after a flood

In geology, a backswamp is a type of depositional environment commonly found in a floodplain. It is where deposits of fine silts and clays settle after a flood. These deposits create a marsh-like landscape that is often poorly drained and usually lower than the rest of the floodplain.

<span class="mw-page-title-main">Marl lake</span> Alkaline lake rich in calcium carbonate

A marl lake is a type of alkaline lake whose bottom sediments include large deposits of marl, a mixture of clay and carbonate minerals. The term is particularly applied to lakes that have been dredged or mined for marl, often for manufacturing Portland cement.

References

Teri red dune complex Habitat in Teri red dune complex JEG3009.JPG
Teri red dune complex
  1. Alappat, Linto; Palaniandy Seralathan, Anil D. Shukla, Kyth Pillai Thrivikramji, Ashok Kumar Singhvi (2013). "Chronology of red dune aggradations of South India and its Palaeo-environmental significance". Geochronometria. 40 (4): 274–282. doi: 10.2478/s13386-013-0118-5 . S2CID   3782587.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. Foote, Robert Bruce (1883). "On the geology of the Madura and Tinnevelly Districts. Chapter 10". Memoirs of the Geological Survey of India. 20: 87–90.
  3. Hendry, D.A. (1987). "Silica and calcium carbonate replacement of plant roots in tropical dune sands, SE India". Geological Society, London, Special Publications. 35 (1): 309–319. Bibcode:1987GSLSP..35..309H. doi:10.1144/GSL.SP.1987.035.01.21. S2CID   128558308.
  4. Gardner, Rita A. M. (1981). "Reddening of dune sands—evidence from southeast India". Earth Surface Processes and Landforms. 6 (5): 459–468. Bibcode:1981ESPL....6..459G. doi:10.1002/esp.3290060506.
  5. Kurian, N.P.; T.N. Prakash; F. Jose; K.P. Black (2001). "Hydrodynamic Processes and Heavy Mineral Deposits of the Southwest Coast, India". Journal of Coastal Research. 34: 154–163.
  6. Jayangondaperumal, R. (2014). "Teri Red Sands, Tamil Nadu". In Vishwas S. Kale (ed.). Landscapes and Landforms of India. World Geomorphological Landscapes. pp. 211–216.