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Journal articles on the topic 'Calcretos'

Author: Grafiati

Published: 7 September 2021

Last updated: 29 July 2025

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1

Horta, José. "Propriedades e classificação dos solos carbonatados e gipsíferos." Geotecnia, no. 59 (June 20, 1990): 03–11. http://dx.doi.org/10.14195/2184-8394_59_1.

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Os solos carbonatados resultantes do desenvolvimento de crostas calcárias (calcretos) em climas sub-húmidos e semiáridos e os solos gipsíferos resultantes do desenvolvimento de crostas gipsíferas (gipcretos) em meios desérticos apresentam propriedades específicas e comportamentos geotécnicos particulares que estão relacionados com o teor de finos carbonatados e gipsíferos. Os ensaios de identificação convencionais encontram sérias restrições e falham quando são aplicados a solos carbonatados e gipsíferos. Neste artigo relatam-se brevemente as propriedades dos solos carbonatados e gipsífe

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2

Patil, Dnyan N., and Arati P. Surana. "Origin of the Calcrete Deposits of Saswad-Nira Area, Western Maharashtra, India." Journal Geological Society of India 39, no. 2 (1992): 105–17. http://dx.doi.org/10.17491/jgsi/1992/390202.

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Abstract Extensive development of calcrete deposits is observed in the Saswad-Nira area of western Maharashtra. Calcrete occurs in a variety of forms, the most common being powder, nodular, laminar, platy, tubular and hardpan calcretes. The DTA, XRD and IR spectroscopic studies show that the calcretes are composed chiefly of micrite - a microcrystalline calcite. Dolomite and opaline silica occur in subordinate amounts. The clay fraction of calcretes is dominated by attapulgite (palygorskite) and sepiolite, which along with other interlayer clay minerals like chlorite-montmorillonite and illite

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3

Aharon, Paul, and Neil E. Whitehead. "Abiotic and Biotic Processes Controlling Deposition of Calcite and Hydrotalcite Calcretes on Niue Island, Southwest Pacific." Minerals 14, no. 9 (2024): 877. http://dx.doi.org/10.3390/min14090877.

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Calcretes are indurated terrestrial carbonates that are widespread in arid and semi-arid settings and serve as important archives of present and past environments. Here, we use geochemical tools to explore the nature and origin of calcretes documented from tropical Niue Island in the Southwest Pacific. The study recognizes two types of calcretes that differ in their mineral assemblage, microfabrics, elemental chemistry, and carbon and oxygen isotopes. The calcretes common in the paleo-lagoon soils consist of 90% low-Mg calcite and ~10% highly weathered Mg-Al silicates. These pedogenic calcrete

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4

Wright, V. P. "Estimating rates of calcrete formation and sediment accretion in ancient alluvial deposits." Geological Magazine 127, no. 3 (1990): 273–76. http://dx.doi.org/10.1017/s0016756800014539.

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AbstractThe use of calcrete horizons as a means of assessing rates of sediment accretion in ancient alluvial sequences is reviewed. Any attempt to use such horizons in quantifying ancient alluvial deposition must appreciate that accurate data on rates of formation of Quaternary calcretes are limited. Such data show considerable variations in the rates and no reliable data exist at all for some calcrete types. The abundance of calcretes in the geological record warrants a new initiative to improve our understanding oftheir origins and rates of formation.

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5

Kadİr, S., M. Eren, T. Külah, N. Önalgİl, M. Cesur, and A. Gürel. "Genesis of Late Miocene-Pliocene lacustrine palygorskite and calcretes from Kırşehir, central Anatolia, Turkey." Clay Minerals 49, no. 3 (2014): 473–94. http://dx.doi.org/10.1180/claymin.2014.049.3.09.

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AbstractThis paper addresses the mineralogy, geochemistry, and genesis of palygorskite and associated calcretes in the Kırşehir region. In this area, the Quaternary calcretes are present within and/or on lacustrine mudstones of the Kızılırmak Formation (Late Miocene-Pliocene). The calcretes occur in the form of nodules, tubes, fracture-infills, and hard laminated crusts (hardpans). Calcrete samples are predominantly composed of calcite associated with smectite, quartz, feldspar, and minor palygorskite. The lacustrine mudstone samples consist mainly of smectite and palygorskite with minor calci

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6

Cooper, Steven J. B., Kathleen M. Saint, Stefano Taiti, Andrew D. Austin, and William F. Humphreys. "Subterranean archipelago: mitochondrial DNA phylogeography of stygobitic isopods (Oniscidea:Haloniscus) from the Yilgarn region of Western Australia." Invertebrate Systematics 22, no. 2 (2008): 195. http://dx.doi.org/10.1071/is07039.

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The arid Yilgarn region of Western Australia contains numerous isolated calcrete aquifers, within which a diverse subterranean fauna has been discovered. Genetic and morphological studies of subterranean dytiscid beetles and amphipods have suggested that individual calcretes are equivalent to closed island habitats, which have been isolated for millions of years. Here we test this ‘subterranean island’ hypothesis further by phylogeographic analyses of subterranean oniscidean isopods (Haloniscus), using mitochondrial DNA (mtDNA) sequence data derived from the cytochrome c oxidase subunit I gene

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7

Ritter, Benedikt, Richard Albert, Aleksandr Rakipov, Frederik M. Van der Wateren, Tibor J. Dunai, and Axel Gerdes. "Late Neogene terrestrial climate reconstruction of the central Namib Desert derived by the combination of U–Pb silcrete and terrestrial cosmogenic nuclide exposure dating." Geochronology 5, no. 2 (2023): 433–50. http://dx.doi.org/10.5194/gchron-5-433-2023.

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Abstract. The chronology of the Cenozoic “Namib Group” of the Namib Desert is rather poorly understood and lacks direct radiometric dating. Thus, the paleoclimate and landscape evolution of the central Namib Desert remains imprecise, complicating the detailed search for global and/or local forcing factors for the aridification of the Namib. The widespread occurrence of calcretes and silcretes in the Namib Desert allows us to apply the novel application of the U–Pb laser ablation dating technique on silcretes and calcretes to date important phases of landscape stability and to retrieve critical

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8

P., Ramesh Chandra Phani, and Srinivas M. "Calcrete Geochemistry in identifying Kimberlite Lamproite Exploration Targets A case study from Nalgonda district, Telangana, southern India." International Journal of Trend in Scientific Research and Development 2, no. 2 (2018): 964–73. https://doi.org/10.31142/ijtsrd9575.

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The pedogenic carbonates, found mainly in arid and semi arid regions of the world, are commonly referred to as calcretes or caliche or kankar. These are authigenic carbonate products which occur in association with soil, forming the residual regolith. Many rock types can produce calcretes upon weathering and denudation, but calcrete derived from certain rocks like kimberlite lamproite acts as an exploration guide. Calcrete is a prominent sampling medium in diamond rich countries like Australia and South Africa whereas it has not received popularity in the Indian context. Kimberlites being ultr

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9

Guzik, M. T., K. M. Abrams, S. J. B. Cooper, W. F. Humphreys, J. L. Cho, and A. D. Austin. "Phylogeography of the ancient Parabathynellidae (Crustacea:Bathynellacea) from the Yilgarn region of Western Australia." Invertebrate Systematics 22, no. 2 (2008): 205. http://dx.doi.org/10.1071/is07040.

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The crustacean order Bathynellacea is a primitive group of subterranean aquatic (stygobitic) invertebrates that typically inhabits freshwater interstitial spaces in alluvia. A striking diversity of species from the bathynellacean family Parabathynellidae have been found in the calcretes of the Yilgarn palaeodrainage system in Western Australia. Taxonomic studies show that most species are restricted in their distribution to a single calcrete, which is consistent with the findings of other phylogeographic studies of stygofauna. In this, the first molecular phylogenetic and phylogeographic study

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Bradford, Tessa M., William F. Humphreys, Andrew D. Austin, and Steven J. B. Cooper. "Identification of trophic niches of subterranean diving beetles in a calcrete aquifer by DNA and stable isotope analyses." Marine and Freshwater Research 65, no. 2 (2014): 95. http://dx.doi.org/10.1071/mf12356.

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The Yilgarn calcrete aquifers in Western Australia are an interesting system for investigating the process of speciation within subterranean habitats, because of the limited opportunities for dispersal between isolated calcretes. The presence of different-sized diving beetles (Dytiscidae) in separate calcretes, including sympatric sister-species pairs, suggests that species may have evolved within calcretes by an adaptive shift as a result of ecological-niche differentiation. We have studied the potential for trophic niche partitioning in a sister triplet of diving beetles, of distinctly diffe

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Anketell, J. M., and S. M. Ghellali. "Stratigraphic Relationships of Basalt Lava Flows to the Pleistocene Sedimentary Sequence of the Mizdah Region, Tripolitania, S.P.L.A.J." Libyan Studies 21 (1990): 61–63. http://dx.doi.org/10.1017/s0263718900001473.

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AbstractCalcreted debris flow breccias which form the lowermost Pleistocene deposits in the Hammadah Al Hamrah region are locally overlain by well cemented conglomerates of the Old Wadi Terraces. These are commonly capped by a younger, mature calcrete which is also found patchily developed on the Tertiary and Mesozoic limestone bedrock. Basalt lava flows rest either on an eroded surface in the conglomerates or directly on the debris flows; however, their relationship to the younger calcrete is rarely seen. In the area north-east of Mizdah a pre-younger calcrete age for the basalts is proposed

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12

Rodas, M., F. J. Luque, R. Mas, and M. G. Garzon. "Calcretes, Palycretes and Silcretes in the Paleogene Detrital Sediments of the Duero and Tajo Basins, Central Spain." Clay Minerals 29, no. 2 (1994): 273–85. http://dx.doi.org/10.1180/claymin.1994.029.2.13.

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AbstractThree duricrust types (calcretes, palycretes and silcretes) have been distinguished in the Lower Paleogene arkosic materials from the margins of the Duero and Tajo basins (central Spain). In the calcretes the cements are composed of calcite plus palygorskite, whereas palygorskite is the only cement in the palycretes. In the silcretes, the cement consists chiefly of opal and chalcedony, with minor quartz. The important duricrust development in the Paleogene detrital materials can be correlated with a drastic climatic change towards colder and more arid conditions during this time, as in

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13

Jutras, Pierre, and Gilbert Prichonnet. "Stratigraphy, depositional setting, and diagenetic history of the Saint-Jules Formation (Upper Devonian or Mississippian), a newly identified post-Acadian red clastic unit in the southern Gaspé Peninsula, Quebec." Canadian Journal of Earth Sciences 39, no. 10 (2002): 1541–51. http://dx.doi.org/10.1139/e02-044.

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The Saint-Jules Formation, a post-Acadian continental clastic unit previously mapped as part of the Bonaventure Formation (pre-Namurian unit), was recently identified in the southern Gaspé Peninsula of Quebec. The Saint-Jules Formation in the study area is confined to a small post-sedimentary graben. The unit is characterized by fault-controlled, oxidized, and poorly sorted detritus that underwent short transportation by fluvial processes. The Saint-Jules Formation is locally overlain by a massive groundwater calcrete several metres in thickness, which is tentatively correlated with the calcre

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14

Andrews, Julian E., Ashok K. Singhvi, Ansu J. Kailath, et al. "Do Stable Isotope Data from Calcrete Record Late Pleistocene Monsoonal Climate Variation in the Thar Desert of India?" Quaternary Research 50, no. 3 (1998): 240–51. http://dx.doi.org/10.1006/qres.1998.2002.

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Late Pleistocene terrestrial climate records in India may be preserved in oxygen and carbon stable isotopes in pedogenic calcrete. Petrography shows that calcrete nodules in Quaternary sediments of the Thar Desert in Rajasthan are pedogenic, with little evidence for postpedogenic alteration. The calcrete occurs in four laterally persistent and one nonpersistent eolian units, separated by colluvial gravel. Thermoluminescence and infrared- and green-light-stimulated luminescence of host quartz and feldspar grains gave age brackets for persistent eolian units I–IV of ca. 70,000–60,000, ca. 60,000

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15

Gaitan Vaz, G., G. P. Mohapatra, and M. Hariprasad. "Orgin and Palaeoenvironmental Aspects of Red Sediments from Bavanapadu-Ichchapuram, Andhra Pradesh." Journal Geological Society of India 52, no. 4 (1998): 463–71. http://dx.doi.org/10.17491/jgsi/1998/520410.

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Abstract Red sediments occur as three shore linear patches between Bavanapadi and Ichchapuram in north Andhra Pradesh coast. The unstructured red sediment lying over an antecedent topography is divisible into lower unit with calcretes and upper unit devoid of calcretes. The field observations, grain size parameters, heavy mineral assemblage and SEM studies of quartz grains signify an aeolian source, possibly formed by sand transport from the exposed continental shelf during the Quaternary regressive cycles. Formation of calcrete and red pigments are considered as post depositional phenomena. S

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16

Adamson, Kathryn, Ian Candy, and Liz Whitfield. "Coupled micromorphological and stable isotope analysis of Quaternary calcrete development." Quaternary Research 84, no. 2 (2015): 272–86. http://dx.doi.org/10.1016/j.yqres.2015.05.002.

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Pedogenic calcretes are widespread in arid and semi-arid regions. Using calcrete profiles from four river terraces of the Rio Alias in southeast Spain, this study explores the potential of using detailed micromorphological and stable isotopic analysis to more fully understand the impacts of Quaternary environmental change on calcrete development. The four profiles increase in carbonate complexity with progressive age, reflecting calcretisation over multiple glacial–interglacial cycles since MIS 9 (c. 300 ka). Calcrete profiles contain a mixture of Alpha (non-biogenic) and Beta (biogenic) micro

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17

Dhir, R. P., S. N. Rajaguru, and A. K. Singhvi. "Desert Quaternary Formations and their Morphostratigraphy: Implications for the Evolutionary History of the Thar." Journal Geological Society of India 43, no. 4 (1994): 435–47. http://dx.doi.org/10.17491/jgsi/1994/430412.

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Abstract Morphogenetic manifestations and stratigraphy of the Quaternary alluvial and aeolian formations of the desertic tract of Rajasthan have been described. The stratigraphy is based on a study of deep sections (-15 m) from different locations. Additionally, well-logs have been used to prepare the isopach maps of these formations. It is inferred that during the major part of the Pleistocene, the region witnessed widespread alluvial sedimentation. Though the region was well-watered then, the presence of large masses of lime coupled with negligible in-situ weathering suggests, that over-all

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18

Larrey, Marine, Frédéric Mouthereau, Emmanuel Masini, et al. "Quaternary tectonic and climate changes at the origin of travertine and calcrete in the eastern Betics (Almería region, SE Spain)." Journal of the Geological Society 177, no. 5 (2020): 939–54. http://dx.doi.org/10.1144/jgs2020-025.

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Continental carbonate bodies are widespread in the Tabernas basin, eastern Betic Cordillera. Their relationships with the topographic evolution, climate changes and extensional regional tectonic processes recognized in the region are, however, still unclear. Travertine deposits exhibit facies of cascade and pool environments often reported as related to water–air surface processes. Calcretes show a large panel of facies, indicating control by groundwater and pedogenic processes. New U/Th dates on both travertine and calcrete reveal that they precipitated from 354 ka ± 76 to 8 ka ± 0.2. The U/T

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19

Roy, Anindya. "Calcrete to kimberlite: A prospector’s hunt for “kimberlite traits” in calcretes." Journal of the Geological Society of India 73, no. 3 (2009): 320–24. http://dx.doi.org/10.1007/s12594-009-0012-1.

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STRONG, G. E., J. R. A. GILES, and V. P. WRIGHT. "A Holocene calcrete from North Yorkshire, England: implications for interpreting palaeoclimates using calcretes." Sedimentology 39, no. 2 (1992): 333–47. http://dx.doi.org/10.1111/j.1365-3091.1992.tb01042.x.

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21

Sydorchuk, V., and V. Zagnitko. "LOCALIZATION FEATURES OF URANIUM MINERALIZATION IN THE TASIAST-TIJIRIT TERRANE, THE REGUIBAT SHIELD." Visnyk of Taras Shevchenko National University of Kyiv. Geology, no. 3 (94) (2021): 90–94. http://dx.doi.org/10.17721/1728-2713.94.11.

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The Reguibat Shield is an area of intensive uranium exploration and about 80 ore occurrences have been discovered in recent decades within its borders. The region of the study is located within the Tasiast-Tijirit terrane, which represents a northwestern part of Archean domain of the Reguibat Shield. The rocks of the terrane are of Mesoarchean age. The main types of rocks are migmatites, gneisses and amphibolites, greenstone associations, granitic intrusions and pegmatites. Samples of pegmatites, granites, ferruginous quartzites and sedimentary rocks that showed an increased radiation level af

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22

Phillips, SE, AR Milnes, and RC Foster. "Calcified filaments - an example of biological influences in the formation of calcrete in South Australia." Soil Research 25, no. 4 (1987): 405. http://dx.doi.org/10.1071/sr9870405.

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Scanning electron microscope (SEM) studies of calcareous soils and calcretes from South Australia reveal a fossilized community of soil micro-organisms dominated by filamentous structures preserved in fine detail by calcite. In the various calcrete lithological facies, the filaments form dense mats within channels and voids, and also occur within the matrix where they are intimately associated with micrite. The calcite forming the filaments has a variety of crystal habits: the nature of the microcrystals is specific to each filament but varies significantly between adjacent filaments. In the c

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Candy, Ian, Stuart Black, and Bruce W. Sellwood. "U-series isochron dating of immature and mature calcretes as a basis for constructing Quaternary landform chronologies for the Sorbas basin, southeast Spain." Quaternary Research 64, no. 1 (2005): 100–111. http://dx.doi.org/10.1016/j.yqres.2005.05.002.

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AbstractImmature and mature calcretes from an alluvial terrace sequence in the Sorbas basin, southeast Spain, were dated by the U-series isochron technique. The immature horizons consistently produced statistically reliable ages of high precision. The mature horizons typically produced statistically unreliable ages but, because of linear trends in the dataset and low errors associated with each data point, it was still possible to place a best-fit isochron through the dataset to produce an age with low associated uncertainties. It is, however, only possible to prove that these statistically un

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Potts, Alastair J., Jeremy J. Midgley, and Chris Harris. "Stable isotope and 14C study of biogenic calcrete in a termite mound, Western Cape, South Africa, and its palaeoenvironmental significance." Quaternary Research 72, no. 2 (2009): 258–64. http://dx.doi.org/10.1016/j.yqres.2009.04.008.

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AbstractLate Quaternary terrestrial climate records from the semi-arid zone of the Western Cape of South Africa are rare. However, palaeoenvironmental information may be inferred from ancient termite mounds of the region. Calcrete lenses in these mounds have δ13C and δ18O values that show systematic changes with radiocarbon dates, which range from 33,629–36,709 to 21,676–23,256 cal yr BP. These dates confirm that these heuweltjies had been present in the landscape since the last glacial period. The decrease in δ13C and δ18O from 33,629–36,709 to 21,676–23,256 cal yr BP indicates that climate i

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Hyde, Josephine, Steven J. B. Cooper, William F. Humphreys, Andrew D. Austin, and Pablo Munguia. "Diversity patterns of subterranean invertebrate fauna in calcretes of the Yilgarn Region, Western Australia." Marine and Freshwater Research 69, no. 1 (2018): 114. http://dx.doi.org/10.1071/mf17005.

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Calcrete aquifers are unique groundwater habitats containing stygobiontic species endemic to each calcrete. The evolutionary history of stygofauna suggests the calcretes in Western Australia contain multiple ancient lineages, yet populations experience episodic variation in rainfall patterns, with little-known ecological consequences. The aim of the present study was to document stygofaunal diversity patterns and determine whether they are influenced by rainfall events. The average taxon richness in boreholes peaked shortly after periods of high rainfall, and when dominant taxa were excluded,

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Alonso-Zarza, Ana M. "Study of a modern calcrete forming in Guadalajara, Central Spain: An analogue for ancient root calcretes." Sedimentary Geology 373 (October 2018): 180–90. http://dx.doi.org/10.1016/j.sedgeo.2018.06.006.

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27

Ram, H., R. P. Singh, and Jagdish Prasad. "Chemical and mineralogical composition of Fe-Mn concretions and calcretes occurring in sodic soils of Eastern Uttar Pradesh, India." Soil Research 39, no. 3 (2001): 641. http://dx.doi.org/10.1071/sr98098.

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The chemical and mineralogical composition of iron–manganese (Fe–Mn) concretions, calcretes (lime nodules), and soil matrix in sodic soils (Typic Halaquepts) from Mirzapur, Faizabad, Ghazipur, and Ballia districts of Uttar Pradesh have been investigated. The data show enrichment of iron and manganese oxides in Fe–Mn concretions, CaCO3 in calcretes, and insoluble constituents in the soil matrix. Hydrochloric acid-insoluble fractions were higher in soil than in concretions and calcretes. Sodium content was also higher in soils than in concretions and calcretes, and it increased with depth. The c

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Sampaio, Lorena Da Fonseca, Patrick Führ Dal’ Bó, Giorgio Basilici, and Thiago Da Silva Marinho. "Interpretação paleoambiental dos calcretes da Formação Marília na região de Uberaba (MG)." Geologia USP. Série Científica 17, no. 2 (2017): 193. http://dx.doi.org/10.11606/issn.2316-9095.v17-423.

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Calcretes são acumulações secundárias de carbonato de cálcio continentais formadas próximo à superfície como resultado de processos pedogenéticos e diagenéticos, produzindo grande variedade de morfologias e texturas. Na Formação Marília (Cretáceo Superior da Bacia Bauru) na região de Uberaba (MG), os calcretes têm sido estudados por seu significado paleoclimático e paleoambiental. Contudo, sua origem e relações entre processos de sedimentação, pedogênese e eodiagênese carecem de estudos detalhados. Em campo, foram distintas quatro morfologias de calcretes no Membro Ponte Alta (nodular, brechos

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Dessai, A. G., and Sudha Warrier. "Mineralogy and Geochemistry of the Calcretes in Alluvial Sediments from Pune, India." Journal Geological Society of India 29, no. 6 (1987): 584–93. http://dx.doi.org/10.17491/jgsi/1987/290605.

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Abstract The calcretes in the alluvial sediments from Pune district, Maharashtra occur as hardpan, powdery, laminated, concretionary and pedotubule horizons. The calcretes are associated with clay minerals belonging to the smectite, chlorite and kaolin groups. The chemical analysis of the calcretes indicates that they are predominantly composed of calcium-carbonate and silica, (Cao: 33 to 37%, SiO2 : 25 to 31%) with magnesium in very subordinate amounts. Trace elements present include Sr, Zr, V, Nb, Y, and Cs. On the basis of textural, mineralogical and chemical data, it is shown that the calc

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30

Candy, Ian, Stuart Black, Bruce W. Sellwood, and John S. Rowan. "Calcrete profile development in Quaternary alluvial sequences, southeast Spain: implications for using calcretes as a basis for landform chronologies." Earth Surface Processes and Landforms 28, no. 2 (2003): 169–85. http://dx.doi.org/10.1002/esp.445.

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Halse, Stuart, and G.B. Pearson. "Troglofauna in the vadose zone: comparison of scraping and trapping results and sampling adequacy." Subterranean Biology 13 (March 7, 2014): 17–34. https://doi.org/10.3897/subtbiol.13.6991.

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Most sampling of troglofauna occurs in caves but troglofauna species are widespread across the vadose zone in Western Australia in iron ore deposits and calcretes. Other than in karstic calcrete, the subterranean spaces in the Western Australian vadose zone are small and often of similar size to the troglofauna inhabiting them. Here we describe how troglofauna can be sampled in the vadose zone using a technique called scraping, in which a haul net is dropped down a hole drilled for geological exploration. We analysed of the results of 10,895 sampling events in which both the scraping and trapp

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ADLER, Paula Braga, Luiz Fernando DE ROS, Kátia Leite MANSUR, and André Luiz FERRARI. "Calcretes pedogenéticos da Bacia de Itaboraí, Estado do Rio de Janeiro." Pesquisas em Geociências 44, no. 2 (2017): 255. http://dx.doi.org/10.22456/1807-9806.78274.

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A Bacia de Itaboraí é considerada o primeiro segmento do Rifte Continental do Sudeste do Brasil a se abrir, durante o Paleoceno. Há referências à existência de calcretes na bacia, entretanto, até o momento, não foram realizados estudos específicos sobre os calcretes e sobre sua ocorrência, e ainda há um número reduzido de trabalhos envolvendo a caracterização petrográfica dos depósitos sedimentares da bacia. Apresenta-se aqui uma caracterização, macromorfológica e micromorfológica dos calcretes vadosos que constituem o preenchimento inicial da bacia e que são encontrados nas suas bordas norte

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Ramakrishnan, D., and K. C. Tiwari. "Calcretes : Geotechnical Appraisal and Efficacy as an Alternative Pavement Material for the Desertic Roads of Western Rajasthan." Journal Geological Society of India 51, no. 1 (1998): 103–7. http://dx.doi.org/10.17491/jgsi/1998/510102.

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Abstract Calcretes are widely distributed in the arid and semi-arid tracts of the Thar Desert. Strategically important roads of this desert region need a suitable, locally available paving material. Mineralogy, physical and geotechnical properties of calcretes indicate their suitability for road pavements.

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Sankara Pitchaiah, P. "Origin of Calcrete in Red Sediment from Visakhapatnam Coast, Andhra Pradesh." Journal Geological Society of India 29, no. 4 (1987): 459–64. http://dx.doi.org/10.17491/jgsi/1987/290412.

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Abstract Red sediment with calcrete is a characteristic deposit in the coastal tracts of Visakhapatnam region on the northeastern part of Andhra Pradesh. Three structural types of calcrete. rhizoconcretionary, mottled and massive, are recognized from Ramakrishna Mission, Rishikonda and Bhimilipatnam areas. Rhizoconcretionary calcrete is recorded from three profiles, but the mottled and massive are typically absent in Bhimilipatnam. The origin of the various types of calcrete in the Visakhapatnam area is intimately linked to evapotranspiration of groundwater. The rootlet origin of the calcrete

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Mann, Eva, Donald F. McNeill, Robert S. Carr, Ryan Franklin, and William J. Pestle. "Geochemical analysis of Tequesta calcretes." Journal of Archaeological Science: Reports 27 (October 2019): 101988. http://dx.doi.org/10.1016/j.jasrep.2019.101988.

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Mmopa, Kehnny Kenanao, and Mahongo Dithinde. "Investigation into the Source of Self-Hardening of Calcrete." Journal of Civil Engineering and Urbanism 14, no. 3s (2024): 339–45. https://doi.org/10.54203/jceu.2024.38.

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Calcrete has been used as road construction material in Botswana for a very long time even though it is classified as marginal or sub-standard material (AFCAP/MOZ/091, 2012). Some calcrete has proved to perform exceptionally well past the road design life and this has been attributed to a property termed self-stabilisation. However, the science behind self-stabilization of some calcrete deposit is not yet fully understood. Accordingly, this paper presents preliminary results of an investigation undertaken to determine the sources of self-stabilization of calcrete deposits. Calcrete samples wer

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Colson, J., I. Cojan, and M. Thiry. "A hydrogeological model for palygorskite formation in the Danian continental facies of the Provence Basin (France)." Clay Minerals 33, no. 2 (1998): 333–47. http://dx.doi.org/10.1180/000985598545516.

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AbstractThe Danian of the Provence basin (SE France) is characterized by a strong subatmospheric alteration processes throughout the basin. A wide range of facies, depositional and weathering, were recognized in an interval of 5 Myr and include floodplain fine-grained alluvium, palustrine limestones, playa dolostones, mottled palaeosols, vadose and phreatic calcretes, and phreatic dolocretes. Palygorskite was invariably found in laminar, massive and honeycomb vadose calcretes and phreatic dolocretes, as well as in playa dolostones, and only exceptionally in floodplain siltstones, nodular calcr

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Küçükuysal, Ceren, and Selim Kapur. "Mineralogical, geochemical and micromorphological evaluation of the Plio-Quaternary paleosols and calcretes from Karahamzall, Ankara (Central Turkey)." Geologica Carpathica 65, no. 3 (2014): 243–55. http://dx.doi.org/10.2478/geoca-2014-0014.

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Abstract We present the mineralogical, micromorphological, and geochemical characteristics of the paleosols and their carbonates from Karahamzall, Ankara (Central Turkey). The paleosols include calcretes of powdery to nodular forms and alternate with channel deposits. The presence of pedofeatures, such as clay cutans, floating grains, circumgranular cracks, MnO linings, secondary carbonate rims, traces of past bioturbation and remnants of root fragments are all the evidence of pedogenesis. Bw is the most common soil horizon showing subangular-angular blocky to granular or prismatic microstruct

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Verrecchia, E. P., and M.-N. Le Coustumer. "Occurrence and genesis of palygorskite and associated clay minerals in a Pleistocene calcrete complex, Sde Boqer, Negev Desert, Israel." Clay Minerals 31, no. 2 (1996): 183–202. http://dx.doi.org/10.1180/claymin.1996.031.2.04.

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AbstractPalygorskite and associated clay minerals have been studied in a Pleistocene calcrete complex from the Negev desert (Sde Boqer, Israel). This complex is divided into five main parts: the chalky and marly bedrock overlain by its weathered product, a brecciated calcrete hardpan; the laminar crust; loess pockets trapped in the calcrete; and the overlying soft surficial soil. The distribution of clay minerals is directly dependent on the position of the sample in the calcrete complex. Smectite is inherited from the bedrock in the calcrete with an aeolian enrichment in loess pockets and upp

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Rossinsky Jr., Victor, Harold R. Wanless, and Peter K. Swart. "Penetrative calcretes and their stratigraphic implications." Geology 20, no. 4 (1992): 331. http://dx.doi.org/10.1130/0091-7613(1992)020<0331:pcatsi>2.3.co;2.

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THERIAULT, P., and A. DESROCHERS. "Carboniferous calcretes in the Canadian Arctic." Sedimentology 40, no. 3 (1993): 449–65. http://dx.doi.org/10.1111/j.1365-3091.1993.tb01345.x.

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Eberhard, Stefan M., Chris H. S. Watts, Shae K. Callan, and Remko Leijs. "Three new subterranean diving beetles (Coleoptera: Dytiscidae) from the Yeelirrie groundwater calcretes, Western Australia, and their distribution between several calcrete deposits including a potential mine site." Records of the Western Australian Museum 31, no. 1 (2016): 27. http://dx.doi.org/10.18195/issn.0312-3162.31(1).2016.027-040.

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Eberhard, Stefan, Chris H.S. Watts, Shae K. Callan, and Remko Leijs. "Three New Subterranean Diving Beetles (Coleoptera: Dytiscidae) from the Yeelirrie Groundwater Calcretes, Western Australia, and Their Distribution Between Several Calcrete Deposits Including a Potential Mine Site." Records of the Western Australian Museum 31 (June 7, 2016): 27–40. https://doi.org/10.5281/zenodo.13672366.

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Bruce, Niel L. "New species and a new genus of Cirolanidae (Isopoda: Cymothoida: Crustacea) from groundwater in calcretes in the Pilbarra, northern Western Australia." Zootaxa 1823 (December 31, 2008): 51–64. https://doi.org/10.5281/zenodo.183029.

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Bruce, Niel L. (2008): New species and a new genus of Cirolanidae (Isopoda: Cymothoida: Crustacea) from groundwater in calcretes in the Pilbarra, northern Western Australia. Zootaxa 1823: 51-64, DOI: 10.5281/zenodo.183029

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Geyh, Mebus A., and Bernhard Eitel. "Radiometric Dating of Young and Old Calcrete." Radiocarbon 40, no. 2 (1997): 795–802. http://dx.doi.org/10.1017/s0033822200018749.

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To obtain a better understanding of the relationship between calcrete genesis and the results of different absolute dating methods, thermoluminescence (TL), radiocarbon (14C) and uranium/thorium (U/Th) were applied to coeval sample; take from a very young calcrete profile in Namibia. The methodically different ages reflect the characteristics of the applied dating methods, the genetics of calcrete and different events of calcrete genesis. The conventional 14C ages and the TL dates cover the last 50 ka, while the corresponding U/Th dates of coeval samples are many times larger, Uranium-series d

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Rakshit, Prabal, and Raghavan Minakshi Sundaram. "Calcrete and Gypsum Crusts of the Thar Desert, Rajasthan, their Geomorphic Locales and Use as Palaeoclimatic Indicators." Journal Geological Society of India 51, no. 2 (1998): 249–55. http://dx.doi.org/10.17491/jgsi/1998/510215.

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Abstract Calcrete and gypsum crusts in Churu-Bikaner areas of the Thar desert, are presently found buried under a cover of aeolian sediments. Non-pedogenic and pedogenic calcrete types occur in various geomorphic locales like, channels, flood plains, pediments etc. Also, different non-pedogenic channel and lacustrine basin-fill gypsum crusts are noted. The occurrences of surface and near surface calcrete, gypsum crusts, their presence in representative sub-surface sequences of fluvio-aeolian sediments indicate climatic vicissitudes in the Late Quaternary from humid to arid and vice versa.

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Basak, Bishnupriya, G. L. Badam, Anupama Kshirsagar, and S. N. Rajaguru. "Late Quaternary Environment, Palaeontology and Culture of Tarafeni Valley, Midnapur District, West Bengal - A Preliminary Study." Journal Geological Society of India 51, no. 6 (1998): 731–40. http://dx.doi.org/10.17491/jgsi/1998/510601.

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Abstract The authors present an integrated data on the Quaternary studies carried out during the 1993-95 field seasons in a lesser known area, the Tarafeni Valley in Midnapur District, West Bengal. Microliths primarily made on chert, quartzite have been found in association with colluvial deposits formed more or less contemporaneously with underlying nodular calcrete of pedogenic Oligin. Occurrence of several vertebrate fossils on the surface of the calcrete at Dhuliapur indicates Late Pleistocene age of the artefact bearing colluvial deposits. The formation of pedogenic calcrete in a sub-humi

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Hirmas, D. R., and B. L. Allen. "Degradation of Pedogenic Calcretes in West Texas." Soil Science Society of America Journal 71, no. 6 (2007): 1878–88. http://dx.doi.org/10.2136/sssaj2006.0351.

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Hirmas, D. R., and B. L. Allen. "Degradation of Pedogenic Calcretes in West Texas." Soil Science Society of America Journal 72, no. 2 (2008): 569–70. http://dx.doi.org/10.2136/sssaj2006.0351er.

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Wright, V. Paul. "Terrestrial stromatolites and laminar calcretes: a review." Sedimentary Geology 65, no. 1-2 (1989): 1–13. http://dx.doi.org/10.1016/0037-0738(89)90002-x.

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