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56-805: The Tendaguru Formation is subdivided into six members; from oldest to youngest Lower Dinosaur Member, the Nerinella Member, the Middle Dinosaur Member, Indotrigonia africana Member, the Upper Dinosaur Member, and the Rutitrigonia bornhardti-schwarzi Member. The succession comprises a sequence of sandstones , shales , siltstones , conglomerates with minor oolitic limestones , deposited in an overall shallow marine to coastal plain environment , characterized by tidal, fluvial and lacustrine influence with

112-469: A coastal plain environment, whereas argillaceous deposits were laid down in still water bodies such as small lakes and ponds. Rare occurrences of the ostracod Cypridea and charophytes signal the influence of freshwater, whereas the sporadic occurrence of marine invertebrates suggests a depositional environment close to the sea. Fining upward sequences of the basal part of the Rutitrigonia bornhardti-schwarzi Member are interpreted as tidal channel fills,

168-480: A lagoonal paleoenvironment. The ostracod Bythocypris sp. from the member indicates polyhaline to euhaline conditions. Slightly higher up, a faunal sample dominated by the bivalve Eomiodon and an ostracod assemblage composed of brackish to freshwater taxa is indicative of a brackish water paleoenvironment with distinct influx of freshwater as revealed by the nonmarine ostracod genus Cypridea , charophytes , and other freshwater algae . The paleoenvironment of

224-480: A thin section using a method like the Gazzi-Dickinson Method . This yields the relative percentages of quartz, feldspar, and lithic grains and the amount of clay matrix. The composition of a sandstone can provide important information on the genesis of the sediments when used with a triangular Q uartz, F eldspar, L ithic fragment ( QFL diagrams ). However, geologist have not been able to agree on

280-666: A tsunami deposit occurring in the Indotrigonia africana Member. The climate of the Late Jurassic and Early Cretaceous was semi-arid with seasonal rainfall and the eustatic sea level was rising in the Late Jurassic from low levels in the Middle Jurassic. Paleogeographical reconstructions show the Tendaguru area was located in the subtropical southern hemisphere during the Late Jurassic. The Tendaguru Formation

336-637: A fossil deposit were first discovered in 1906, when German pharmacist, chemical analyst and mining engineer Bernhard Wilhelm Sattler, on his way to a mine south of the Mbemkure River in German East Africa (today Tanzania ), was shown by his local staff enormous bones weathering out of the path near the base of Tendaguru Hill, 10 kilometres (6.2 mi) south of Mtapaia (close to Nambiranji village, Mipingo ward, 60 kilometres (37 mi) northwest of Lindi town). Because of its morphology,

392-478: A sandstone goes through as the degree of kinetic processing of the sediments increases. Dott's (1964) sandstone classification scheme is one of many such schemes used by geologists for classifying sandstones. Dott's scheme is a modification of Gilbert's classification of silicate sandstones, and it incorporates R.L. Folk's dual textural and compositional maturity concepts into one classification system. The philosophy behind combining Gilbert's and R. L. Folk's schemes

448-462: A set of boundaries separating regions of the QFL triangle. Visual aids are diagrams that allow geologists to interpret different characteristics of a sandstone. For example, a QFL chart can be marked with a provenance model that shows the likely tectonic origin of sandstones with various compositions of framework grains. Likewise, the stage of textural maturity chart illustrates the different stages that

504-445: A twofold classification: Cement is what binds the siliciclastic framework grains together. Cement is a secondary mineral that forms after deposition and during burial of the sandstone. These cementing materials may be either silicate minerals or non-silicate minerals, such as calcite. Sandstone that becomes depleted of its cement binder through weathering gradually becomes friable and unstable. This process can be somewhat reversed by

560-837: Is a distinction that can be recognized in the field . In turn, the distinction between an orthoquartzite and a metaquartzite is the onset of recrystallization of existing grains. The dividing line may be placed at the point where strained quartz grains begin to be replaced by new, unstrained, small quartz grains, producing a mortar texture that can be identified in thin sections under a polarizing microscope. With increasing grade of metamorphism, further recrystallization produces foam texture , characterized by polygonal grains meeting at triple junctions, and then porphyroblastic texture , characterized by coarse, irregular grains, including some larger grains ( porphyroblasts .) Sandstone has been used since prehistoric times for construction, decorative art works and tools. It has been widely employed around

616-550: Is composed of quartz or feldspar , because they are the most resistant minerals to the weathering processes at the Earth's surface. Like uncemented sand , sandstone may be imparted any color by impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Because sandstone beds can form highly visible cliffs and other topographic features, certain colors of sandstone have become strongly identified with certain regions, such as

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672-478: Is considered the richest Late Jurassic strata in Africa . The formation has provided a wealth of fossils of different groups; early mammaliaforms , several genera of dinosaurs , crocodyliforms , amphibians , fish , invertebrates and flora . More than 250 tonnes (250 long tons; 280 short tons) of material was shipped to Germany during early excavations in the early twentieth century. The faunal assemblage of

728-494: Is divided into 6 members, which represent different depositional environments , with the 'Dinosaur Beds' representing terrestrial facies while the beds with genus/species names represent marine interbeds with shallow marine to lagoonal facies. In ascending order these are: the Lower Dinosaur Member, the Nerinella Member, the Middle Dinosaur Member, Indotrigonia africana Member, the Upper Dinosaur Member, and

784-523: Is likely formed during eogenesis. Deeper burial is accompanied by mesogenesis , during which most of the compaction and lithification takes place. Compaction takes place as the sand comes under increasing pressure from overlying sediments. Sediment grains move into more compact arrangements, ductile grains (such as mica grains) are deformed, and pore space is reduced. In addition to this physical compaction, chemical compaction may take place via pressure solution . Points of contact between grains are under

840-431: Is redeposited in the unstrained pore spaces. Mechanical compaction takes place primarily at depths less than 1,000 meters (3,300 ft). Chemical compaction continues to depths of 2,000 meters (6,600 ft), and most cementation takes place at depths of 2,000–5,000 meters (6,600–16,400 ft). Unroofing of buried sandstone is accompanied by telogenesis , the third and final stage of diagenesis. As erosion reduces

896-443: Is that it is better able to "portray the continuous nature of textural variation from mudstone to arenite and from stable to unstable grain composition". Dott's classification scheme is based on the mineralogy of framework grains, and on the type of matrix present in between the framework grains. In this specific classification scheme, Dott has set the boundary between arenite and wackes at 15% matrix. In addition, Dott also breaks up

952-846: The Alcobaça , Guimarota and Lourinhã Formations of Portugal , the Villar del Arzobispo Formation of Spain , the Shishugou , Kalazha and Shangshaximiao Formations in China, the Toqui Formation of Chile and Cañadón Calcáreo Formation and the Morrison Formation, with the presence of dinosaurs with similar counterparts, e.g., Brachiosaurus and Stegosaurus in the Morrison, and Giraffatitan and Kentrosaurus in

1008-576: The British Museum (Natural History), London (1924–1931) launched a series of collecting expeditions that remain unequalled in scope and ambition. Led by the vision and influence of geologist Wilhelm von Branca , the German expeditions were particularly successful, in large part because the project was taken up as a matter of national ambition (Germany was then a young nation, having been unified by von Bismarck less than 40 years earlier) and enjoyed

1064-568: The Global Heritage Stone Resource . In some regions of Argentina, the orthoquartzite-stoned facade is one of the main features of the Mar del Plata style bungalows. Depositional environment In geology , depositional environment or sedimentary environment describes the combination of physical, chemical, and biological processes associated with the deposition of a particular type of sediment and, therefore,

1120-484: The Nerinella Member, in particular for the lower part. Sedimentation occurred as tidal channel fills, subtidal and tidal sand bars , minor storm layers ( tempestites ), and beach deposits. Overall, the Nerinella Member represents a variety of shallow subtidal to lower intertidal environments influenced by tides and storms. The sedimentological characteristics of the basal part of the Middle Dinosaur Member suggest deposition on tidal flats and in small tidal channels of

1176-582: The Rutitrigonia bornhardti-schwarzi Member. The Tendaguru Formation was deposited in the Mandawa Basin , a post- Karoo , Mesozoic rift basin located between the Ruvu Basin and Rufiji Trough to the north and the Ruvuma Basin to the south. To the west of the basin, Archean and Early Proterozoic basement rocks crop out . The main rift phase in present-day southeastern Africa led to

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1232-769: The Villar del Arzobispo Formation of Spain , the Shishugou , Kalazha and Shangshaximiao Formations of China , and the Toqui Formation of the Magallanes Basin , Chile and the Cañadón Calcáreo Formation of the Cañadón Asfalto Basin in central Patagonia , Argentina . Sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains, cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks . Most sandstone

1288-488: The provenance and possible restitution of colonial heritage, as discussed for example in the 2018 report on the restitution of African cultural heritage , both German as well as Tanzanian commentators have called the claim to rightful ownership by the Berlin museum into question. The Tanzanian government has, however, not submitted any official demand for repatriation. German authorities have preferred to offer information on

1344-542: The rock types that will be formed after lithification , if the sediment is preserved in the rock record. In most cases, the environments associated with particular rock types or associations of rock types can be matched to existing analogues. However, the further back in geological time sediments were deposited, the more likely that direct modern analogues are not available (e.g. banded iron formations ). Continental Transitional Marine Others Depositional environments in ancient sediments are recognised using

1400-548: The Dwanika and Bolachikombe stream sections, and in a small tributary of the Bolachikombe creek, a discrete, up to 70 centimetres (2.3 ft) thick conglomerate in the lower portion of the Indotrigonia africana Member displays evidence of a tsunami deposit. Overall, lithofacies and the diverse macroinvertebrate and microfossil assemblages of the Indotrigonia africana Member suggest a shallow marine environment. Based on

1456-707: The German engineer Sattler. Possible dinosaur eggs have been recovered from the formation. The fauna of the Tendaguru Formation has been correlated with the Morrison Formation of the central-western United States, several formations in England, among which the Kimmeridge Clay and Oxford Clay , and France ( Sables de Glos , Argiles d'Octeville , Marnes de Bléville ), the Alcobaça , Guimarota and Lourinhã Formations of Portugal ,

1512-626: The Kimmeridgian into the Early Cretaceous, but retained a continental connection with South America. Global sea levels dropped significantly in the Early Jurassic and remained low through the Middle Jurassic but rose considerably towards the Late Jurassic, deepening the marine trenches between continents. The sedimentary rocks and fossils record a repeated shift from shallow marine to tidal flat environments indicating that

1568-547: The Tendaguru is similar to the Morrison Formation of the central-western United States, with an additional marine interbed fauna not present in the Morrison. The dinosaur fauna found in the formation is similar to that of other highly fossiliferous stratigraphic units of the Late Jurassic; among others the Kimmeridge and Oxford Clays of England , the Sables de Glos , Argiles d'Octeville , Marnes de Bléville of France ,

1624-540: The Tendaguru. The Tendaguru Formation represents the oldest sedimentary unit in the Mandawa Basin , directly overlying Neoproterozoic basement consisting of gneiss . The contact contains a large hiatus, a missing sequence of stratigraphy, spanning the Paleozoic, Triassic and Early Jurassic. The formation is unconformably overlain by late Early Cretaceous sediments of the Makonde Formation , that forms

1680-491: The application of tetraethyl orthosilicate (Si(OC 2 H 5 ) 4 ) which will deposit amorphous silicon dioxide between the sand grains. The reaction is as follows. Pore space includes the open spaces within a rock or a soil. The pore space in a rock has a direct relationship to the porosity and permeability of the rock. The porosity and permeability are directly influenced by the way the sand grains are packed together. Sandstones are typically classified by point-counting

1736-747: The benevolence of many wealthy patrons. Eventually, nearly 250 tons of bones, representing an entirely new dinosaur fauna that remains the best understood assemblage from all of former Gondwana, was shipped to Berlin. From there, the material was transported to Fraas' institution, the Royal Natural History Collection in Stuttgart , Germany . Fraas described two species in the badly known genus " Gigantosaurus " ; G. robustus and G. africanus (today Janenschia robusta and Tornieria africana , respectively). The Berlin's Natural History Museum excavated at Tendaguru hill and in

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1792-867: The coast. Stacked successions of trough cross-bedded, medium- to coarse-grained sandstone of the upper part of the Indotrigonia africana Member are interpreted as tidal channel and sand bar deposits. At some places in the surroundings of Tendaguru Hill, these sediments interfinger with oolitic limestone layers that represent high-energy ooid shoals . In the Tingutinguti stream section, the Indotrigonia africana Member exhibits several up to 20 centimetres (7.9 in) thick, poorly sorted, conglomeratic sandstone beds. They contain mud clasts , reworked concretions and/or accumulations of thick-shelled bivalves (mainly Indotrigonia africana and Seebachia janenschi ), and exhibit megaripple surfaces. These conglomeratic sandstone layers are interpreted as storm deposits. In

1848-473: The common minerals most resistant to weathering processes at the Earth's surface, as seen in the Goldich dissolution series . Framework grains can be classified into several different categories based on their mineral composition: Matrix is very fine material, which is present within interstitial pore space between the framework grains. The nature of the matrix within the interstitial pore space results in

1904-456: The depositional environment, older sand is buried by younger sediments, and it undergoes diagenesis . This mostly consists of compaction and lithification of the sand. Early stages of diagenesis, described as eogenesis , take place at shallow depths (a few tens of meters) and are characterized by bioturbation and mineralogical changes in the sands, with only slight compaction. The red hematite that gives red bed sandstones their color

1960-407: The depth of burial, renewed exposure to meteoric water produces additional changes to the sandstone, such as dissolution of some of the cement to produce secondary porosity . Framework grains are sand-sized (0.0625-to-2-millimeter (0.00246 to 0.07874 in) diameter) detrital fragments that make up the bulk of a sandstone. Most framework grains are composed of quartz or feldspar , which are

2016-446: The different types of framework grains that can be present in a sandstone into three major categories: quartz, feldspar, and lithic grains. When sandstone is subjected to the great heat and pressure associated with regional metamorphism , the individual quartz grains recrystallize, along with the former cementing material, to form the metamorphic rock called quartzite . Most or all of the original texture and sedimentary structures of

2072-400: The diverse mesoflora and the abundance of Classopollis , a nearby vegetated hinterland is postulated that was dominated by xerophytic conifers . The small-scale trough and ripple cross-bedded fine-grained sandstone at the base of the Upper Dinosaur Member is interpreted as tidal flat deposits. Unfossiliferous sandstone in the upper part was most likely deposited in small fluvial channels in

2128-433: The greatest strain, and the strained mineral is more soluble than the rest of the grain. As a result, the contact points are dissolved away, allowing the grains to come into closer contact. Lithification follows closely on compaction, as increased temperatures at depth hasten deposition of cement that binds the grains together. Pressure solution contributes to cementing, as the mineral dissolved from strained contact points

2184-442: The hardness of individual grains, uniformity of grain size and friability of their structure, some types of sandstone are excellent materials from which to make grindstones , for sharpening blades and other implements. Non-friable sandstone can be used to make grindstones for grinding grain, e.g., gritstone . A type of pure quartz sandstone, orthoquartzite, with more of 90–95 percent of quartz, has been proposed for nomination to

2240-503: The hill was locally known as "steep hill": "tendaguru" in the language of the local Wamwera people . Sattler sent a report of the discoveries that found its way to German palaeontologist Eberhard Fraas , then on a round trip through Africa, who visited the site in 1907 and with the aid of Sattler recovered two partial skeletons of enormous size. Following the discovery in 1906, teams from the Museum für Naturkunde, Berlin (1907–1913), and

2296-704: The lower part of the Indotrigonia africana Member that shows highly variable transport directions is interpreted as deposits of large tidal channels. Grain-size, large-scale sedimentary structures, and the lack of both trace fossils and epifaunal and infaunal body fossils suggest high water energy and frequent reworking. This basal succession passes upward in cross-bedded sandstone and minor siltstone and claystone with flaser or lenticular bedding that are interpreted as tidal flat and tidal channel deposits. Horizontal to low-angle cross-bedded, fine-grained sandstone with intercalated bivalve pavements indicates tidal currents that operated in small flood and ebb tidal deltas and along

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2352-493: The much lower temperatures and pressures associated with diagenesis of sedimentary rock, but diagenesis has cemented the rock so thoroughly that microscopic examination is necessary to distinguish it from metamorphic quartzite. The term orthoquartzite is used to distinguish such sedimentary rock from metaquartzite produced by metamorphism. By extension, the term orthoquartzite has occasionally been more generally applied to any quartz-cemented quartz arenite . Orthoquartzite (in

2408-464: The narrow sense) is often 99% SiO 2 with only very minor amounts of iron oxide and trace resistant minerals such as zircon , rutile and magnetite . Although few fossils are normally present, the original texture and sedimentary structures are preserved. The typical distinction between a true orthoquartzite and an ordinary quartz sandstone is that an orthoquartzite is so highly cemented that it will fracture across grains, not around them. This

2464-461: The ostracod assemblages of the Middle Dinosaur Member changed upsection from a marine setting in the basal parts through alternating marine-brackish conditions to freshwater conditions in the higher parts of this member. The highly sporadic occurrence, in this part of the section, of molluscs typical of marginal marine habitats indicates only a very weak marine influence, at sabkha-like coastal plains with ephemeral brackish lakes and ponds are recorded in

2520-441: The overlying fine-grained sandstone, silt- and claystone as tidal flat deposits. From the immediate surroundings of Tendaguru Hill, invertebrates and vertebrates are poorly known and limit the palaeoenvironmental interpretation of this member. The composition of the land-derived sporomorph assemblage suggests a terrestrial vegetation which was dominated by cheirolepidiacean conifers in association with ferns . The Tendaguru Beds as

2576-638: The product of physical and chemical weathering of bedrock. Weathering and erosion are most rapid in areas of high relief, such as volcanic arcs , areas of continental rifting , and orogenic belts . Eroded sand is transported by rivers or by the wind from its source areas to depositional environments where tectonics has created accommodation space for sediments to accumulate. Forearc basins tend to accumulate sand rich in lithic grains and plagioclase . Intracontinental basins and grabens along continental margins are also common environments for deposition of sand. As sediments continue to accumulate in

2632-522: The provenance and research by increasing cooperation between Tanzanian paleontologists and museums with their German counterparts. In 1998, an illustrated book in Swahili, whose title translates as Dinosaurs of Tendaguru , was published for young readers in East Africa. It presents a slightly different, fictitious story of the first discovery, which is attributed to a Tanzanian farmer, rather than to

2688-712: The red rock deserts of Arches National Park and other areas of the American Southwest . Rock formations composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs . Quartz-bearing sandstone can be changed into quartzite through metamorphism , usually related to tectonic compression within orogenic belts . Sandstones are clastic in origin (as opposed to either organic , like chalk and coal , or chemical , like gypsum and jasper ). The silicate sand grains from which they form are

2744-417: The sandstone are erased by the metamorphism. The grains are so tightly interlocked that when the rock is broken, it fractures through the grains to form an irregular or conchoidal fracture. Geologists had recognized by 1941 that some rocks show the macroscopic characteristics of quartzite, even though they have not undergone metamorphism at high pressure and temperature. These rocks have been subject only to

2800-644: The separation of Madagascar and the then-connected Indian subcontinent happened during the Early Cretaceous. The Songo Songo and Kiliwani gas fields are located just offshore the basin. At time of deposition was undergoing a semi-arid climate with coastal influences that maintained somewhat higher moisture levels than seen inland. The upper parts of the formation, the Middle Dinosaur and Rutitrigonia bornhardti-schwarzi Members in particular, showed prevailing semiarid conditions with pronounced dry seasons, based on palynologic analysis. The Tendaguru fauna

2856-436: The strata of the Tendaguru Formation were deposited near an oscillating strandline which was controlled by sea level changes. The three dinosaur-bearing members are continental to marginal marine and the three sandstone-dominated members are marginal marine in origin. The composition of benthic molluscs and foraminifera, euhaline to mesohaline ostracods, and dinoflagellate assemblages indicate marine, shallow water conditions for

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2912-479: The surroundings for four years. From 1909 through 1911, Werner Janensch as expedition leader and Edwin Hennig as assistant directed excavations, while Hans Reck and his wife Ina Reck led the 1912 field season. Other European participants include Hans von Staff. In the rainy seasons the scientists explored the geology of the colony German East Africa on long safaris. In the context of international discussion about

2968-408: The top of several plateaus; Namunda, Rondo, Noto, and Likonde-Kitale. Based on extended geological and paleontological observations the "Tendaguruschichten" (Tendaguru Beds) were defined by Werner Janensch as expedition leader and Edwin Hennig in 1914 to define a sequence of Late Jurassic to Early Cretaceous strata, exposed in the Tendaguru area, which is named after Tendaguru Hill. The Tendaguru

3024-402: The upper part of the Middle Dinosaur Member. This part also contains pedogenic calcretes indicating subaerial exposure and the onset of soil formation. The calcrete intraclasts within adjacent sandstone beds testify to erosive reworking of calcrete horizons. The presence of crocodyilforms indicates freshwater to littoral environments and adjacent terrestrial areas. The coarse-grained sandstone of

3080-626: The world in constructing temples, churches, homes and other buildings, and in civil engineering . Although its resistance to weathering varies, sandstone is easy to work. That makes it a common building and paving material, including in asphalt concrete . However, some types that have been used in the past, such as the Collyhurst sandstone used in North West England , have had poor long-term weather resistance, necessitating repair and replacement in older buildings. Because of

3136-811: Was stable through the Late Jurassic. During the Late Jurassic and Early Cretaceous, the Gondwana paleocontinent was breaking up and the separation of the Laurasian and Gondwana supercontinents resulted from the connection of the Tethys Ocean with the proto-Atlantic and the Pacific Ocean. In addition, the South Atlantic developed towards the end of the Late Jurassic with the separation of South America and Africa. Africa became increasingly isolated from most other continents by marine barriers from

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