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39-493: The main outcrop of the formation, represents an active private extraction site. The first extraction activities of the famous Saltrio stone give back to the times of the ancient Romans, with modern reports of activity in this quarry since 1400. In the Monte Oro area, on the southern slope of Monte Orsa, there were numerous trench quarries which were used to extract this precious rock, used both for structural constructions and for

78-941: A feedstock in the synthesis of commercial fertilizer powders. In Brazil , greensand refers to a fertilizer produced from a glauconitic siltstone unit belonging to the Serra da Saudade Formation, Bambuí Group, of Neoproterozoic / Ediacaran age. The outcrops occur in the Serra da Saudade ridge, in the Alto Paranaíba region, Minas Gerais state. It is a silty-clayed sedimentary rock, laminated, bluish-green, composed of glauconite (40-80%), potassium feldspar (10-15%), quartz (10-60%), muscovite (5%) and minor quantities of biotite (2%), goethite (<1%), titanium and manganese oxides (<1%), barium phosphate and rare-earth element phosphates (<1%). Enriched levels of potash have K 2 O grades between 8 and 12%, thickness up to 50 metres (160 ft) and are associated to

117-526: A marl in an old and broad sense of that word. Thus references to "greensand marl" sometimes refer specifically to glauconite. The Glauconitic Marl formation is named after it, and there is a glauconitic sandstone formation in the Mannville Group of Western Canada . At the broadest level, glauconite is an authigenic mineral and forms exclusively in marine settings. It is commonly associated with low-oxygen conditions. Normally, glauconite

156-529: A consequence of diagenetic alteration of sedimentary deposits at the surface, bio-chemical reduction and subsequent mineralogical changes affecting iron-bearing micas such as biotite , and is also influenced by the decaying process of organic matter degraded by bacteria in marine animal shells. In these cases, the organic matter creates the reducing environment needed to form glauconite within otherwise oxygenated sediment. Glauconite deposits are commonly found in nearshore sands, open oceans and shallow seas, such as

195-403: A division between two near subsiding basins located at Mt. Nudo (East) and Mt. Generoso (West). It settled over a carbonate platform linked with other wider areas that appear along the west to the southeast, developing a large shallow water gulf to the north, where the strata deposited was controlled by a horst and tectonic gaben. The Saltrio layers represent a unique sedimentary environment that

234-597: A gradual transition from Upper Rhaetian shallow-water carbonates to Lombard siliceous limestone and thick Lower Liassic series. The Dinosaur Fossils found on the Saltrio formation can have been translated from this area, or alternatively, the Arbostora swell (that was located at the north of the Saltrio formation, on Switzerland ). This was an emerged structural high close to the Saltrio Formation , that caused

273-481: A gulf of the Mt. Nudo basin, where they became fossilized. The latter possibility was suggested by Lualdi (1999), in which he analyzed the local geology based on the presence of terrestrial plants and terrigenous content (sands from igneous or metamorphic rocks exposed to sub-aerial erosion) in the limestones. Terrestrial plants are essentially represented by leaves and small branches of Araucariaceans and Bennettitales ,

312-617: A rich ammonite fauna support subsidence during the same period. The sediment composition varies in different areas, often containing reworked material from older rocks. The Saltrio environment was complex, with different layers showing distinct conditions. In some areas, the Saltrio layers blend with the "Broccatello d'Arzo", a related limestone formation, but they can still be separated based on differences in their structure and fossil content. The region also experienced sedimentary discontinuities, where layers were not deposited continuously, likely due to tectonic activity or submarine erosion. Overall,

351-430: Is 2.4–2.95. It is normally found as dark green rounded concretions with the dimensions of a sand grain. It can be confused with chlorite (also of green color) or with a clay mineral . Glauconite has the chemical formula (K,Na)(Fe,Al,Mg) 2 (Si,Al) 4 O 10 (OH) 2 . Glauconite particles are one of the main components of greensand , glauconitic siltstone and glauconitic sandstone . Glauconite has been called

390-524: Is a rather a complex series of specimens, whose classification is controversial. Rhynchonella R. acanthica “Salnova” quarry A Rhynchonellatan , member of the family Wellerellidae inside Rhynchonellida . Another series of Specimens of uncertain placement. [REDACTED] Astarte “Salnova” quarry A Clam , type member of the family Astartidae inside Carditida . Some shells identified as Cardium probably belong to this genus. Avicula “Salnova” quarry A Pearl Oyster , member of

429-512: Is considered a diagnostic mineral indicative of continental shelf marine depositional environments with slow rates of accumulation and gradational boundaries. For instance, it appears in Jurassic /lower Cretaceous deposits of greensand , so-called after the coloration caused by glauconite, its presence gradually lessening further landward. It can also be found in sand or clay formations, or in impure limestones and in chalk . It develops as

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468-612: Is considered as more important "Main". The formation is found in: It is primarily made of dolomite , ranging from 0 to 2,200 metres (0 to 7,218 ft) in thickness. Main Dolomite is represented by the medium bedded dolomitic layers often with characteristic stromatolitic lamination. The formation was deposited in shallow lagoons during the Late Carnian and Early Norian ages of the Late Triassic Epoch in

507-514: Is derived from the Greek glaucos ( γλαυκός ) meaning 'bluish green', referring to the common blue-green color of the mineral; its sheen ( mica glimmer) and blue-green color. Its color ranges from olive green, black green to bluish green, and yellowish on exposed surfaces due to oxidation. In the Mohs scale it has a hardness of 2, roughly the same as gypsum . The relative specific gravity range

546-439: Is different from both the "Formazione di Saltrio" and the "Saltrio calcarenite" described by earlier researchers. These layers are characterized by being transgressive deposits, meaning they formed as the sea advanced over previously exposed land. The Saltrio deposits show signs of stratigraphic condensation, which refers to slow sediment accumulation over time, often resulting in hardgrounds, surfaces drilled by marine organisms, and

585-646: Is extracted. In today's quarry what is mainly known as the Saltrio Formation emerges, i.e., a group of stratified rocks dating back to the Lower Jurassic. The stratigraphy, however, is much more complex, even if so far no study has focused on this topic. Inside the quarry, Dolomia principale sediment emerges dating back to the Upper Triassic (Norian); yet the succession is dominated by the Saltrio Formation, here 15-20 meters thick. Above,

624-566: Is its use in Russian " icon paintings", another widespread use was for underpainting of human flesh in medieval painting. It is also found as mineral pigment in wall paintings from the ancient Roman Gaul . Glauconite, a major component of greensand , is a common source of potassium (K ) in plant fertilizers and is also used to adjust soil pH . It is used for soil conditioning in both organic and non-organic farming, whether as an unprocessed material (mixed in adequate proportions) or as

663-865: The Alps of Europe. Formation was defined by K.W. Gümbel in 1857. Middle to Late Triassic sedimentary record in the Alpine realm is characterized by presence of various masses of dolomitic rock formations. In the Northern Calcareous Alps the dolomitic mass of Ladinian - Norian age is divided by the Carnian sandstones and shales of Lunz Formation to the Ladinian - Carnian Wetterstein Dolomite and Norian Main Dolomite. The Main Dolomite reaches higher thickness than underlying dolomites in Alps, therefore it

702-536: The Mediterranean Sea . Glauconite remains absent in fresh-water lakes, but is noted in shelf sediments of the western Black Sea . The wide distribution of these sandy deposits was first made known by naturalists on board the fifth HMS Challenger , in the expedition of 1872–1876. Glauconite has long been used in Europe as a green pigment for artistic oil paint under the name green earth . One example

741-596: The Moltrasio Formation emerges, a greyish-brown limestone composed of biocalcarenite and containing widespread nodules of spongolitic silica. This rock is rarely fossiliferous except in the contact areas between the Formations. At the roof of the Moltrasio Fm, a whitish yellow limestone emerges, again of marine-pelagic origin, where there is a lot of micro-diffused silica within the sediment. Since

780-536: The Triassic Period , during the Mesozoic Era . Fossil sauropodomorph tracks, likely made by a plateosaurid , have been reported from the formation. Glauconite Glauconite is an iron potassium phyllosilicate ( mica group) mineral of characteristic green color which is very friable and has very low weathering resistance. It crystallizes with a monoclinic geometry. Its name

819-412: The wind farm industry off the coasts of Massachusetts , New York and New Jersey , glauconite-rich sands of Cretaceous to Paleogene age found in the seabed have become a hazard to the installation of monopiles used for turbine foundation. When these sands are manipulated, during the driving of monopiles, they start to crush, changing their geotechnical behaviour from sand-like to clay-like, with

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858-696: The Hettangian-Sinemurian, the current location of the modern Maggiore Lake were covered with forests, what was proven by the presence of large plant fragments on the Moltrasio Formation . The plants have been recovered between the locations of Cellina and Arolo (eastern side of Lake Maggiore), from rocks that have been found to be coeval in age to the Saltrio Formation . The Flora includes genera such as Bennettitales ( Ptilophyllum ), terrestrial Araucariaceae ( Pagiophyllum ), and Cheirolepidiaceae ( Brachyphyllum ), that developed on inland areas with dry-warm conditions. The ammonites from

897-545: The Saltrio Formation allow the formation to be dated to the Early Sinemurian . Animals probably lived in emerged parts of carbonated platform or an area to the northwest, whose presence had never been established. In the early Sinemurian, the Arbostora swell became again a shallow open sea (ramp-slope), still surrounded South and South-West by emerged land. The dinosaur bones where washed on this period, flowed into

936-399: The Saltrio paleoenvironment reflects a shallow marine setting with fluctuating sea levels, rich marine life, and periods of sediment reworking and erosion, all influenced by local tectonics. Several outcrops of the so-called “terra rossa” paleosoils were also found, including at Castello Cabiaglio-Orino , a dozen of kilometers West of Saltrio. This outcrops show that the emerged areas that on

975-583: The base of the Formation. The contact between the Main Dolomite and the Saltrio Formation also contains selachian teeth, glauconite and phosphated internal models of ammonites. Since the beginning of the jurassic, from Hettangian to earliest Sinemurian on the western Lombardy Basin there was a notorious continental area that was found to be wider than previously thought, where a warm humid paleoclimate developed. The basin facies are characterized by

1014-517: The early 1900s, fossil finds have been known in the Salnova Quarry and in the various quarry sites present in the surroundings of this site. The first written testimonies, and subsequent revisions, are reported starting from the sixties by Giulia Sacchi Vialli. The scholar describes the fossil faunas of Saltrio by listing and detailing various taxa belonging to ammonoids, nautiloids, gastropods, crinoids, brachiopods and bivalves. In that period,

1053-478: The east and west by relatively deep marine basins. Large theropods could not live in an atoll, since large areas had to be emersed to provide food and fresh water, and their herbivorous prey needed land with vegetation. " It is more likely that the Peri-Adriatic Platforms worked with temporary continental bridges that connected with Laurasia Gondwana in central Tethis, allowing migration between

1092-725: The entire Upper Sinemurian. The taxa attributable to the Lower Sinemurian found in the Saltrio quarries probably come from the base of the formation or have been reworked. According to Sacchi-Vialli, the Formation includes taxa indicative of all the biozones between the Bucklandi Zone (Lower Sinemurian) and the Obtusum Zone, and possibly also of the Oxynotum Zone of the Upper Sinemurian, present at

1131-413: The extraction method and processing, changed. From classic and manual extraction we move on to the use of heavy mechanical means and extraction with explosives: the moved rubble increases considerably, making it easier to observe other specimens, new lithologies and above all different faunas. The fauna present at the base of the Saltrio Formation is condensed and includes ammonoids of species attributed to

1170-431: The family Pteriidae inside Ostreida . Abundant and rather easy to identify. Calvaentolium “Salnova” quarry A Scallop , member of the family Pectinoidae inside Pectinida . It was identified originally as "Pecten (Pseudamusium) hehlii". Cardinia “Salnova” quarry A Clam , type member of the family Cardiniidae inside Carditida . Epicontinental deposits genus, rather abundant locally. Cardinia rugosa

1209-436: The family Spiriferinidae inside Spiriferinida . Was identified originally as "Spiriferina haasi". Lobothyris L. punctata “Salnova” quarry A Rhynchonellatan , member of the family Lobothyrididae inside Terebratulida . Was identified originally as "Terebratula punctata". Spiriferina S. expansa “Salnova” quarry A Rhynchonellatan , type member of the family Spiriferinidae inside Spiriferinida . It

Saltrio Formation - Misplaced Pages Continue

1248-515: The glauconitic levels, dark-green in color. Glauconite is authigenic and highly mature . The high concentration of this mineral is related to a depositional environment with a low sedimentation rate. The glauconitic siltstone has resulted from a high-level flooding event in the Bambuí Basin. The sedimentary provenance is from supracrustal felsic elements in a continental margin environment with acid magmatic arc ( foreland basin ). In

1287-420: The great phase of extraction of ornamental stone using manual-mechanical methods had just ended in the quarry. Paleontologists could only recover fossils from the waste flakes near the quarry and therefore the possibility of seeing more specimens was limited to the length of manual operations. In those years, however, the quarry was acquired by Salnova SPA (1969): the purpose of the extracted material, and therefore

1326-481: The lower Jurassic ( Hettangian - Sinemurian ) in the province of Trento , around 160 kilometres (99 mi) east of Saltrio , which changed the traditional view of the palaeoenvironments and paleogeography of the region, considered a tropical sea with small islands of the atoll type. Fossil footprints and tracks are preserved in tidal carbonates deposited in a relatively narrow carbonated platform in Trento, flanked to

1365-476: The presence of minerals like Glauconite and Phosphorite . Biologically, these layers are rich in fossils, especially Encrinite (crinoid-rich limestones) and bivalve lumachellas (fossilized bivalve shells). Other marine creatures like cephalopods and brachiopods appear occasionally. Faunas from the condensed Saltrio beds indicate early subsidence in the Hettangian. Additionally, the involutine limestones with

1404-400: The production of artefacts and artistic works. In more recent times the mining activity has been transformed and we have moved from the extraction of stone for construction to the extraction for the production of stabilized and split crushed stone, useful for the production of motorway foundations and mixtures for the production of asphalt. To date it is the only active quarry where Saltrio stone

1443-543: The two hemispheres and colonization of local coastal habitats. During the marine transgressions, some of these lands were isolated, implicating genetic Mutations in their terrestrial faunas, with typical biological consequences, as endemism and possible dwarfism ". Cirpa C. variabilis “Salnova” quarry A Rhynchonellatan , member of the family Wellerellidae inside Rhynchonellida . Identified originally as "Rhynchonella variabilis". Liospiriferina L. rostrata “Salnova” quarry A Rhynchonellatan , member of

1482-538: The typical flora of the early Mesozoic . However, plants and sand (which are not abundantly referred) can be carried by wind and ocean currents. Also, according to the most current paleogeographic maps, truly continental land located closer these Jurassic times lower were the Mountains of Sardinia , Corsica , distanced many tens of kilometers WNW. Coeval and slightly younger in age, large dinosaurs, carnivorous and herbivorous, were present as shown in various footprints of

1521-399: Was first discovered on this formation. Cardium “Salnova” quarry A Clam , member of the family Cardiniidae inside Carditida . Rare locally, with some specimens considered dubious. Chlamys “Salnova” quarry Dolomia principale Main Dolomite ( German : Hauptdolomit , Hungarian : Fődolomit , Italian : Dolomia Principale ) is a lithostratigraphic unit in

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