Geochemistry characteristics of the Low Permian sedimentary rocks from central uplift zone, Qiangtang Basin, Tibet: insights into source-area weathering, provenance, recycling, and tectonic setting

The sedimentary rocks of the Madzaringwe Formation in the Tuli Basin have been investigated using geochemical and petrographic methods to reveal their source area composition, tectonic setting, provenance and paleoweathering conditions. The petrographic studies show that the rocks consist mostly of clay minerals and quartz. The major elements geochemistry indicates that the rocks of the Madzaringwe Formation have the same source area. Based on the discriminant function plots, it can be inferred that the rocks are of quartzose sedimentary provenance, suggesting that they were derived from a cratonic interior or recycled orogen. The binary plots of TiO2 versus Zr and La/Sr against Th/Co shows that the rocks were derived from silicic or felsic igneous rocks. The tectonic setting discrimination diagrams of SiO2 against Log (K2O/Na2O), Th–Sc–Zr/10, and TiO2 versus (Fe2O3 + MgO) support passive-active continental margin settings of the provenance. The A–CN–K (Al2O3–CaO + Na2O–K2O) ternary diagram and binary plot of the index of compositional variability (ICV) against chemical index of alteration (CIA) shows that the rocks have been subjected to moderate to intensive weathering. Geochemical and petrographic characteristics of the rocks point to uplifted basement source areas predominantly composed of sedimentary rocks and/or granite-gneiss rocks. These source areas might have been from adjacent areas near the Tuli coalfield which include the Limpopo Belt (igneous and sedimentary rocks), and basement uplifted rocks of the Beit-Bridge Complex, consisting of the granite, granite-gneisses and schists.

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PROVENANCE AND TECTONIC SETTING OF SOME PALEOPROTEROZOIC SEDIMENTARY ROCKS IN THE CHAGUPANA AND TARKWA AREAS OF GHANA: PETROGRAPHIC AND STRUCTURAL CONSTRAINTS

Earth Science Malaysia ◽

10.26480/esmy.01.2020.01.07 ◽

2020 ◽

Vol 4 (1) ◽

pp. 01-07

Author(s):

Blestmond A. Brako ◽

Gordon Foli ◽

Etornam B. Fiadonu ◽

Chiri Amedjoe ◽

Derrick Aikins ◽

...

Keyword(s):

Tectonic Setting ◽

Sedimentary Rocks ◽

Source Area ◽

Mineralogical Composition ◽

Structural Constraints ◽

The North ◽

Humid Environment ◽

Multiple Recycling ◽

Semi Arid ◽

Rock Source

Paleoproterozoic sedimentary rocks associated with the Man Shield of West Africa are perceived to be similar, irrespective of their locality. This research seeks to establish the provenance and tectonic setting of these rocks to ascertain any such similarity perception, based on information from two localities. The study uses modal mineral estimations to reconstruct the source, paleocurrent, paleoclimate and relief of some conglomerates and sandstones from Chagupana and Tarkwa areas in Ghana. Chagupana conglomerate has igneous and metamorphic provenances, while Kawere conglomerate has metamorphic provenance. Average mineralogical composition of Chagupana sandstone is Q53-F45-R3 and classify as arkose. Tarkwa suites of Huni, Kawere and Banket sandstones are composed of Q48-F34-R18, Q51-F25-R23 and Q76-F7-R17, and classify as lithic arkose, lithic arkose-feldspathic litharenite, and sublitharenite, respectively. Detritus of all the sandstones suggest acid igneous rock source, with minor sedimentary and metamorphic imprints, with an order of maturity as Banket>Kawere>Huni>Chagupana. Detritus in the Chagupana, Huni and Kawere sandstones are from the transitional continental margin. The Chagupana is from the cold arid climate, while the Huni and Kawere are from the semi-arid/semi-humid climates. The Banket sandstone mobilises from craton interior with recycled orogenic materials in a humid environment. The angular-subangular feldspars in Chagupana sandstone indicate low relief and low-moderate recycling close to the source. Huni, Kawere and Banket sandstones derive from low-moderate reliefs with multiple recycling episodes. The Chagupana and Huni sandstones show paleo-current directions from the north and east, respectively. Similarities between the Chagupana and Tarkwa rocks can only be limited to the tectonic setting and not from source area, paleo-climate, paleo-current and relief.

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Geochemistry and detrital zircon geochronology of the Lower Jurassic clastic rocks of the northern Qiangtang Basin, northern Tibet: Implications for palaeoenvironment, provenance, and tectonic setting

Geological Journal ◽

10.1002/gj.4074 ◽

2021 ◽

Author(s):

Shengqiang Zeng ◽

Jian Wang ◽

Xiugen Fu ◽

Wenbin Chen ◽

Chunyan Song ◽

...

Keyword(s):

Detrital Zircon ◽

Tectonic Setting ◽

Lower Jurassic ◽

Zircon Geochronology ◽

Detrital Zircon Geochronology ◽

Qiangtang Basin ◽

Clastic Rocks ◽

Northern Tibet

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Provenance, tectonic setting and source area-paleoweathering of sandstones of the Bahariya Formation in the Bahariya Oasis, Egypt: An implication to paleoclimate and paleogeography of the southern Neo-Tethys region during Early Cenomanian

Sedimentary Geology ◽

10.1016/j.sedgeo.2020.105822 ◽

2021 ◽

Vol 413 ◽

pp. 105822

Author(s):

Hamdalla A. Wanas ◽

Ehab M. Assal

Keyword(s):

Tectonic Setting ◽

Source Area ◽

Bahariya Formation ◽

Bahariya Oasis

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Petrography and provenance of the Marambio Group, Vega Island, Antarctica

Antarctic Science ◽

10.1017/s0954102094000775 ◽

1994 ◽

Vol 6 (4) ◽

pp. 517-527 ◽

Cited By ~ 12

Author(s):

Duncan Pirrie

Keyword(s):

Late Cretaceous ◽

Sedimentary Rocks ◽

Clay Mineralogy ◽

Minor Component ◽

Source Area ◽

Low Grade ◽

Western Margin ◽

Sediment Input ◽

A Minor ◽

Sandstone Petrography

Late Cretaceous sedimentary rocks assigned to the Santa Marta (Herbert Sound Member) and López de Bertodano (Cape Lamb and Sandwich Bluff members) formations of the Marambio Group, crop out on Cape Lamb, Vega Island. Although previous studies have recognized that these sedimentary rocks were derived from the northern Antarctic Peninsula region, the work presented here allows the provenance and palaeogeographical evolution of the region to be described in detail. On the basis of both sandstone petrography and clay mineralogy, the Herbert Sound and Cape Lamb members reflect sediment input from a low relief source area, with sand grade sediment sourced from low grade metasediments, and clay grade sediment ultimately derived from the weathering of an andesitic source area. In contrast, the Sandwich Bluff Member reflects a switch to a predominantly andesitic volcaniclastic source. However, this sediment was largely derived from older volcanic suites due to renewed source area uplift, with only a minor component from coeval volcanism. Regional uplift of both the arc terrane and the western margin of the James Ross Basin was likely during the Maastrichtian.

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Provenance of Jurassic sedimentary rocks of south-central Quesnellia, British Columbia: implications for paleogeography

Canadian Journal of Earth Sciences ◽

10.1139/e03-073 ◽

2004 ◽

Vol 41 (1) ◽

pp. 103-125 ◽

Cited By ~ 12

Author(s):

Nathan T Petersen ◽

Paul L Smith ◽

James K Mortensen ◽

Robert A Creaser ◽

Howard W Tipper

Keyword(s):

Detrital Zircon ◽

Middle Jurassic ◽

Sedimentary Rocks ◽

Source Area ◽

Lower Jurassic ◽

Early Jurassic ◽

Late Triassic ◽

Nd Isotopes ◽

South Central ◽

History Of

Jurassic sedimentary rocks of southern to central Quesnellia record the history of the Quesnellian magmatic arc and reflect increasing continental influence throughout the Jurassic history of the terrane. Standard petrographic point counts, geochemistry, SmNd isotopes and detrital zircon geochronology, were employed to study provenance of rocks obtained from three areas of the terrane. Lower Jurassic sedimentary rocks, classified by inferred proximity to their source areas as proximal or proximal basin are derived from an arc source area. Sandstones of this age are immature. The rocks are geochemically and isotopically primitive. Detrital zircon populations, based on a limited number of analyses, have homogeneous Late Triassic or Early Jurassic ages, reflecting local derivation from Quesnellian arc sources. Middle Jurassic proximal and proximal basin sedimentary rocks show a trend toward more evolved mature sediments and evolved geochemical characteristics. The sandstones show a change to more mature grain components when compared with Lower Jurassic sedimentary rocks. There is a decrease in εNdT values of the sedimentary rocks and Proterozoic detrital zircon grains are present. This change is probably due to a combination of two factors: (1) pre-Middle Jurassic erosion of the Late Triassic Early Jurassic arc of Quesnellia, making it a less dominant source, and (2) the increase in importance of the eastern parts of Quesnellia and the pericratonic terranes, such as Kootenay Terrane, both with characteristically more evolved isotopic values. Basin shale environments throughout the Jurassic show continental influence that is reflected in the evolved geochemistry and SmNd isotopes of the sedimentary rocks. The data suggest southern Quesnellia received material from the North American continent throughout the Jurassic but that this continental influence was diluted by proximal arc sources in the rocks of proximal derivation. The presence of continent-derived material in the distal sedimentary rocks of this study suggests that southern Quesnellia is comparable to known pericratonic terranes.

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