Journal articles: 'Permian volcanism'

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Tripathi, C. "Volcanism in Gondwanas." Journal of Palaeosciences 36 (December 31, 1987): 285–89. http://dx.doi.org/10.54991/jop.1987.1587.

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In India the Lower Permian event is marked by a major volcanic episode in the Himalayan belt and rift faulting in the Peninsula which gave rise to various Gondwana basins. The Lower Cretaceous major volcanic episode represented by the Rajmahal Trap represents the termination of Gondwana sedimentation. Lower Permian volcanism is represented by the Panjal Volcanics in Kashmir Basin and its equivalent, the Volcanics in Spiti-Zanskar Basin and Rotung Volcanics (Abor Volcanics) in Arunachal Pradesh. In Karakarom Basin of Ladakh, volcanism is associated with Changtash and Aqtash formations of Permian age. The Agglomeratic Slates in Kashmir are supposed to have originated as explosive volcanism in the form of pyroclastic which was followed later by flows of the Panjal Volcanics represented by subaqueous and subaerial tholeiitic basalt with occasional basaltic, andesitic and rhyolitic volcanics. The Agglomeratic slates are divided into two divisions, the Lower Diamicites and the Upper Pyroclastic. At the base of the Pyroclastic division and at the top of the Diamictite division, we get Eurydesma-Deltopecten Fauna of Lower Permian age. It is thus established that volcanism in Kashmir, Spiti-Zanskar and Ladakh is restricted to Lower Permian only. The sills and dykes associated with the underlying sequence in Syringothyris Limestone and Fenestella Shale in Kashmir, in Lipak and Po Formations in Spiti are related to this volcanism.

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AWDANKIEWICZ, MAREK, RYSZARD KRYZA, and NORBERT SZCZEPARA. "Timing of post-collisional volcanism in the eastern part of the Variscan Belt: constraints from SHRIMP zircon dating of Permian rhyolites in the North-Sudetic Basin (SW Poland)." Geological Magazine 151, no. 4 (September 12, 2013): 611–28. http://dx.doi.org/10.1017/s0016756813000678.

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AbstractThe final stages of the Variscan orogeny in Central Europe were associated with voluminous granitic plutonism and widespread volcanism. Four samples representative of the main rhyolitic volcanic units from the Stephanian–Permian continental succession of the North-Sudetic Basin, in the eastern part of the Variscan Belt, were dated using the SIMS (SHRIMP) zircon method. Three samples show overlapping206Pb–238U mean ages of 294 ± 3, 293 ± 2 and 292 ± 2 Ma, and constrain the age of the rhyolitic volcanism in the North-Sudetic Basin at 294–292 Ma. This age corresponds to the Early Permian – Sakmarian Stage and is consistent with the stratigraphic position of the lava units. The fourth sample dated at 288 ± 4 Ma reflects a minor, younger stage of (sub)volcanic activity in the Artinskian. The silicic activity was shortly followed by mafic volcanism. The rhyolite samples contained very few inherited zircons, possibly owing to limited contribution of crustal sources to the silicic magma, or owing to processes involved in anatectic melting and magma differentiation (e.g. resorption of old zircon by Zr-undersaturated melts). The SHRIMP results and the stratigraphic evidence suggest that the bimodal volcanism terminated the early, short-lived (10–15 Ma) and vigorous stage of basin evolution. The Permian volcanism in the North-Sudetic Basin may be correlated with relatively late phases of the regional climax of Late Palaeozoic volcanism in Central Europe, constrained by 41 published SHRIMP zircon age determinations at 299–291 Ma. The Permian volcanism and coeval plutonism in the NE part of the Bohemian Massif can be linked to late Variscan, post-collisional extension.

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Brown, Derek A., James M. Logan, Michael H. Gunning, Michael J. Orchard, and Wayne E. Bamber. "Stratigraphic evolution of the Paleozoic Stikine assemblage in the Stikine and Iskut rivers area, northwestern British Columbia." Canadian Journal of Earth Sciences 28, no. 6 (June 1, 1991): 958–72. http://dx.doi.org/10.1139/e91-087.

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The Stikine assemblage, the "basement" of Stikinia, extends 500 km along the western flank of the Intermontane Belt, east of younger Coast Belt plutons. Four different stratigraphic successions are characteristic of Lower to Middle Devonian, Carboniferous and Permian rocks in the Stikine and Iskut rivers area. West of Forrest Kerr Creek are penetratively deformed Lower to Middle Devonian island-arc volcaniclastic rocks, coralline limestone, and felsic tuff. Fringing carbonate buildups in an arc setting are best illustrated in the sequence at Round Lake where Lower Carboniferous mafic-dominated, bimodal submarine volcanic rocks grade upward into two distinctive coarse echinoderm limestone units and medial siliceous siltstone and limestone conglomerate. Conodont colour alteration indices for Lower Carboniferous rocks near Newmont Lake indicate an anomalously low-temperature thermal history. Upper Carboniferous–Permian polymictic volcanic conglomerate and Lower Permian limestone overlie these strata there. The Scud River sequence is distinguished by subgreenschist- to greenschist-grade Carboniferous(?) volcanic and sedimentary rocks overlain by a structurally thickened package (greater than 1000 m) of Lower Permian limestone. Local calcalkaline pyroclastic rocks interfinger with limestone near the top of the Scud River sequence. Basinal, shelf, and shallow-water carbonate facies developed in the Early Permian, giving way to calcalkaline volcanism in Late Permian followed by deposition of deep-water chert and argillite.The tectonic setting during the Devonian and Carboniferous is comparable with modern Pacific volcanic arcs and atolls, but there is no modern analogue for the shelf-carbonate accumulation during the Early Permian which characterizes the Stikine assemblage and permits Cordilleran-scale correlations. Permian fusulinid and coral species have very close affinity to those of the McCloud Limestone of the eastern Klamath Mountains, California. Other geologic events common to both Stikinia and the Eastern Klamath terrane are Devonian limestone breccia deposition, Lower Permian limestone accumulation with McCloud faunal affinity, Carboniferous and Permian calcalkaline volcanism, and Upper Permian tuffaceous limestone. Stratigraphic differences include the absence of quartz detritus in Devonian strata and lack of thick Upper Permian volcanic rocks in the Stikine River area.

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Vozárová, Anna, Sergey Presnyakov, Katarína Šarinová, and Miloš Šmelko. "First evidence for Permian-Triassic boundary volcanism in the Northern Gemericum: geochemistry and U-Pb zircon geochronology." Geologica Carpathica 66, no. 5 (October 1, 2015): 375–91. http://dx.doi.org/10.1515/geoca-2015-0032.

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AbstractSeveral magmatic events based on U-Pb zircon geochronology were recognized in the Permian sedimentary succession of the Northern Gemeric Unit (NGU). The Kungurian magmatic event is dominant. The later magmatism stage was documented at the Permian-Triassic boundary. The detrital zircon assemblages from surrounding sediments documented the Sakmarian magmatic age. The post-orogenic extensional/transtensional faulting controlled the magma ascent and its emplacement. The magmatic products are represented by the calc-alkaline volcanic rocks, ranging from basaltic metaandesite to metarhyolite, associated with subordinate metabasalt. The whole group of the studied NGU Permian metavolcanics has values for the Nb/La ratio at (0.44–0.27) and for the Nb/U ratio at (9.55–4.18), which suggests that they represent mainly crustal melts. Magma derivation from continental crust or underplated crust is also indicated by high values of Y/Nb ratios, ranging from 1.63 to 4.01. The new206U–238Pb zircon ages (concordia age at 269 ± 7 Ma) confirm the dominant Kungurian volcanic event in the NGU Permian sedimentary basin. Simultaneously, the Permian-Triassic boundary volcanism at 251 ± 4 Ma has been found for the first time. The NGU Permian volcanic activity was related to a polyphase extensional tectonic regime. Based on the new and previous U-Pb zircon ages, the bulk of the NGU Permian magmatic activity occurred during the Sakmarian and Kungurian. It was linked to the post-orogenic transpression/transtension tectonic movements that reflected the consolidation of the Variscan orogenic belt. The Permian-Triassic boundary magmatism was accompanied by extension, connected with the beginning of the Alpine Wilson cycle.

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5

Lindgreen, H., and F. Surlyk. "Upper Permian-Lower Cretaceous clay mineralogy of East Greenland: provenance, palaeoclimate and volcanicity." Clay Minerals 35, no. 5 (December 2000): 791–806. http://dx.doi.org/10.1180/000985500547241.

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AbstractThe clay mineralogy of Upper Permian–Lower Cretaceous mudstones from East Greenland has been investigated by X-ray diffraction (XRD), atomic force microscopy (AFM) and thermal analysis in order to evaluate long-term trends in provenance and palaeoclimate and to detect possible volcanic events. The Upper Permian–Lower Triassic mudstones contain illite, chlorite, vermiculite, kaolinite and illite-smectite (I-S), whereas the Rhaetian–Sinemurian mudstones are dominated by kaolinite. Aalenian–Albian mudstones contain kaolinite and large amounts of I-S with ˜80% illite layers. Exceptions are three Kimmeridgian samples, which contain mainly I-S with 30% illite layers, and three Upper Barremian–Lower Aptian samples with large amounts of smectite layers. Discrete clay minerals in the Upper Permian–Jurassic mudstones are largely detrital. The smectite-rich I-S probably reflects episodes of volcanic activity in late Jurassic and late Barremian–early Aptian times. This is the first indication of Mesozoic volcanism from the Mesozoic rift basin of East Greenland. The main sediment source during late Permian–early Cretaceous times was weathered Precambrian and Caledonian crystalline basement. The only possibly climate-induced change is a change from chlorite, illite, vermiculite and kaolinite in Upper Permian–Lower Triassic mudstones to kaolinite and I-S in the Jurassic mudstones and is probably due to an increase in precipitation.

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6

Francis, E. H. "Mid-Devonian to early Permian volcanism: Old World." Geological Society, London, Special Publications 38, no. 1 (1988): 573–84. http://dx.doi.org/10.1144/gsl.sp.1988.038.01.39.

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7

ZHU, YONGFENG, SHIHUA SUN, LIBING GU, YOSHIHIDE OGASAWARA, NENG JIANG, and HIROJI HONMA. "Permian volcanism in the Mongolian orogenic zone, northeast China: geochemistry, magma sources and petrogenesis." Geological Magazine 138, no. 2 (March 2001): 101–15. http://dx.doi.org/10.1017/s0016756801005210.

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Lower Permian volcanism was the first magmatic activity to occur after the collision events in the Mongolian orogenic zone, east China. The Permian volcanic rocks are therefore a key to understanding the dynamics of the unified continental lithosphere. The volcanic rocks consist of basic and intermediate rocks. The intermediate rocks with high initial 87Sr/86Sr ratios (0.7051 to 0.7052) and low εNd values (−0.73 to −3.57) generally overlie the basic rocks in the field. The basic rocks have relatively low initial 87Sr/86Sr ratios (0.7034 to 0.7051) and high εNd values (2.72 to −0.10). Two parallel Rb–Sr isochrons give almost the same age, about 270 Ma. One consists of the basic rocks giving an initial isochron 87Sr/86Sr ratio of 0.7035. The other consists of the intermediate rocks and one sample of basalt, which give an initial isochron 87Sr/86Sr value of 0.7051. The strong correlations between SiO2 and other major elements suggest that fractional crystallization played an important role in the magmatic processes. However, fractional crystallization cannot explain the geochemistry of most incompatible trace elements and Sr–Nd isotope characteristics. The positive correlation between Th/Nb and (La/Sm)N ratios demonstrates the direct relation between the enrichment of the light rare earth elements and the contamination of continental sediments. The high contents of large ion lithosphere elements (LILE) in the Permian volcanic rocks may suggest an additional ‘crust + fluid’ component, especially in the intermediate rocks, which are highly enriched in Ba (> 400 ppm) relative to the basic rocks (> 200 ppm). We propose that the subduction slab dropped into depleted mantle and released fluid, which induced the mantle metasomatism and LILE enrichment. The metasomatized mantle partially melted and formed the ‘primary’ magma. This primary magma assimilated with the Proterozoic biotite–quartz schist during its rise, and finally formed the Permian volcanic rocks. Magma assimilated with the Proterozoic biotite–quartz schist in small amounts could have produced the basic rocks, while assimilation of larger amounts of magma (because of longer assimilation time) would generate intermediate rocks.

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8

Zheng, Binsong, Chuanlong Mou, Renjie Zhou, Xiuping Wang, Zhaohui Xiao, and Yao Chen. "Nature and origin of the volcanic ash beds near the Permian–Triassic boundary in South China: new data and their geological implications." Geological Magazine 157, no. 4 (December 3, 2019): 677–89. http://dx.doi.org/10.1017/s001675681900133x.

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AbstractPermian–Triassic boundary (PTB) volcanic ash beds are widely distributed in South China and were proposed to have a connection with the PTB mass extinction and the assemblage of Pangea. However, their source and tectonic affinity have been highly debated. We present zircon U–Pb ages, trace-element and Hf isotopic data on three new-found PTB volcanic ash beds in the western Hubei area, South China. Laser ablation inductively coupled plasma mass spectrometry U–Pb dating of zircons yields ages of 252.2 ± 3.6 Ma, 251.6 ± 4.9 Ma and 250.4 ± 2.4 Ma for these three volcanic ash beds. Zircons of age c. 240–270 Ma zircons have negative εHf(t) values (–18.17 to –3.91) and Mesoproterozoic–Palaeoproterozoic two-stage Hf model ages (THf2) (1.33–2.23 Ga). Integrated with other PTB ash beds in South China, zircon trace-element signatures and Hf isotopes indicate that they were likely sourced from intermediate to felsic volcanic centres along the Simao–Indochina convergent continental margin. The Qinling convergent continental margin might be another possible source but needs further investigation. Our data support the model that strong convergent margin volcanism took place around South China during late Permian – Early Triassic time, especially in the Simao–Indochina active continental margin and possibly the Qinling active continental margin. These volcanisms overlap temporally with the PTB biocrisis triggered by the Siberian Large Igneous Province. In addition, our data argue that the South China Craton and the Simao–Indochina block had not been amalgamated with the main body of Pangea by late Permian – Early Triassic time.

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Hrdličková, Kristýna, Altanbaatar Battushig, Pavel Hanžl, Alice Zavřelová, and Jitka Míková. "Lower Permian basaltic agglomerate from the Tsengel River valley, Mongolian Altai." Mongolian Geoscientist 51 (December 21, 2020): 1–11. http://dx.doi.org/10.5564/mgs.v51i0.1457.

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A new occurrence of Permian volcanic and volcaniclastic rocks in the Mongolian Altai south of the Main Mongolian Lineament was described between soums of Tugrug and Tseel in Gobi-Altai aimag. Studied vitrophyric pyroxene basalt lies in a layer of agglomerate and amygdaloidal lavas, which is a part of NE–SW trending subvertical sequence of varicolored siltstones and volcaniclastic rocks in the Tsengel River valley. This high-Mg basalt is enriched in large ion lithophile elements, Pb and Sr and depleted in Nb and Ta. LA-ICP-MS dating on 44 spots reveals several concordia clusters. The whole rock geochemistry of sample fits volcanic arc characteristic in the geotectonic discrimination diagrams. Dominant zircon data yield Upper Carboniferous and Permian magmatic ages 304.4 ± 2.3 and 288.6 ± 1.9 Ma. Two smaller clusters of Upper Devonian (376 ± 4.7 Ma) to Lower Carboniferous ages (351.9 ± 3.5 Ma) indicate probably contamination of ascending magmatic material. Youngest Triassic age found in three morphologically differing grains reflects probably lead loss. Described high-Mg basalt lava represents sub-aerial volcanism in volcanic arc environment developed over the N dipping subduction zone in the southwestern Mongolia in the time span from Uppermost Carboniferous to Permian during terminal stage of its activity.

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HILTON, JASON, WANG SHI-JUN, JEAN GALTIER, IAN GLASSPOOL, and LIL STEVENS. "An Upper Permian permineralized plant assemblage in volcaniclastic tuff from the Xuanwei Formation, Guizhou Province, southern China, and its palaeofloristic significance." Geological Magazine 141, no. 6 (November 2004): 661–74. http://dx.doi.org/10.1017/s0016756804009847.

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A new permineralized fossil plant assemblage is described from volcaniclastic tuff collected in the Upper Permian (Wuchiapigian to Changhsingian) Xuanwei Formation at Shanjiaoshu mine, Guizhou Province, China. The assemblage is fragmentary but contains a small sphenopsid strobilus, a partial strobilus of a lepidodendralean lycopsid, pinnae of the filicalean fern Anachoropteris and a filicalean non-laminate fertile pinna rachis, the marattialean ferns Eoangiopteris, Scolecopteris and Psaronius, hooked stems of probable gigantopterid affinity, and two kinds of cardiocarpalean ovules. This represents the first indisputable evidence of Anachoropteris from the Permian of China, and contrasts with previous evidence from Europe and North America that indicates this genus became extinct during earliest Permian times. The assemblage highlights the persistence of plants from wetland communities and mire ecosystems into the Upper Permian of southern China, and adds further support to the presence of the Ameriosinian phytogeographical realm. This represents the first record of a plant assemblage preserved in volcaniclastic sediments from the Upper Permian of southern China, and in combination with other recently discovered plant assemblages in similar deposits in southern China, suggests volcanism to be an important factor in facilitating permineralized plant preservation in this realm. Although the source of the volcanism that produced the tuff is unknown, its age and location are consistent with the Emishan Large Igneous Province (LIP) of southwest China.

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Rößler, Ronny. "The most entirely known Permian terrestrial ecosystem on Earth – kept by explosive volcanism." Palaeontographica Abteilung B 303, no. 1-3 (August 6, 2021): 1–75. http://dx.doi.org/10.1127/palb/2021/0072.

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Chauvet, François, Henriette Lapierre, Delphine Bosch, Stéphane Guillot, Georges Mascle, Jean-Claude Vannay, Jo Cotten, Pierre Brunet, and Francine Keller. "Geochemistry of the Panjal Traps basalts (NW Himalaya): records of the Pangea Permian break-up." Bulletin de la Société Géologique de France 179, no. 4 (July 1, 2008): 383–95. http://dx.doi.org/10.2113/gssgfbull.179.4.383.

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AbstractThe late Lower to Middle Permian Panjal Traps (NW Himalaya, India-Pakistan) represent the greatest magmatic province erupted on the northern Indian platform during the Neotethys opening. New geochemical and isotopic analyses were performed on basalts from the eastern borders of the traps (SE Zanskar-NW Spiti area) in order to characterize this volcanism, to discuss its compositional variations in comparison to Panjal counterparts and its relationships with the opening of Neotethys. Lavas show features of tholeiitic low-Ti (< 1.6%) continental flood basalts with LREE, Th enrichments and Nb-Ta negative anomalies. Trace element ratios combined with εNdi values (−3.6 to +0.9) and high Pb isotopic ratios suggest that these tholeiitic basalts were derived from an OIB-like mantle contaminated at various degrees by a continental crust component. Previous geochemical features are broadly similar to those of the coeval Panjal volcanic sequences identified westwards (Ladakh, Kashmir and Pakistan). Present geochemical constraints obtained for the Panjal Traps basalts suggest they originated from rapid effusion of tholeiitic melts during opening of the Neotethys Ocean. Similar magmatism implying an OIB-type reservoir is contemporaneously recognized on and along the adjacent Arabian platform. Both Indian and Arabian Permian volcanics were emplaced during coeval syn-rift to post rift transition. These Lower to Middle Permian south Neotethyan continental flood magmatism are regarded as associated to a passive rifting. In this scheme, OIB-type isotopic signature would be related either to a melting episode of syn-rift up-welling mantle plumes or to a melting of a regional abnormally hot and enriched mantle.

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Bond, David P. G., Paul B. Wignall, and Stephen E. Grasby. "The Capitanian (Guadalupian, Middle Permian) mass extinction in NW Pangea (Borup Fiord, Arctic Canada): A global crisis driven by volcanism and anoxia." GSA Bulletin 132, no. 5-6 (August 30, 2019): 931–42. http://dx.doi.org/10.1130/b35281.1.

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Abstract Until recently, the biotic crisis that occurred within the Capitanian Stage (Middle Permian, ca. 262 Ma) was known only from equatorial (Tethyan) latitudes, and its global extent was poorly resolved. The discovery of a Boreal Capitanian crisis in Spitsbergen, with losses of similar magnitude to those in low latitudes, indicated that the event was geographically widespread, but further non-Tethyan records are needed to confirm this as a true mass extinction. The cause of this crisis is similarly controversial: While the temporal coincidence of the extinction and the onset of volcanism in the Emeishan large igneous province in China provides a clear link between those phenomena, the proximal kill mechanism is unclear. Here, we present an integrated fossil, pyrite framboid, and geochemical study of the Middle to Late Permian section of the Sverdrup Basin at Borup Fiord, Ellesmere Island, Arctic Canada. As in Spitsbergen, the Capitanian extinction is recorded by brachiopods in a chert/limestone succession 30–40 m below the Permian-Triassic boundary. The extinction level shows elevated concentrations of redox-sensitive trace metals (Mo, V, U, Mn), and contemporary pyrite framboid populations are dominated by small individuals, suggestive of a causal role for anoxia in the wider Boreal crisis. Mercury concentrations—a proxy for volcanism—are generally low throughout the succession but are elevated at the extinction level, and this spike withstands normalization to total organic carbon, total sulfur, and aluminum. We suggest this is the smoking gun of eruptions in the distant Emeishan large igneous province, which drove high-latitude anoxia via global warming. Although the global Capitanian extinction might have had different regional mechanisms, like the more famous extinction at the end of the Permian, each had its roots in large igneous province volcanism.

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Ellwood, Brooks B., Galina P. Nestell, Luu Thi Phuong Lan, Merlynd K. Nestell, Jonathan H. Tomkin, Kenneth T. Ratcliffe, Wei-Hsung Wang, et al. "The Permian–Triassic boundary Lung Cam expanded section, Vietnam, as a high-resolution proxy for the GSSP at Meishan, China." Geological Magazine 157, no. 1 (June 14, 2019): 65–79. http://dx.doi.org/10.1017/s0016756819000566.

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AbstractThe Lung Cam expanded stratigraphic succession in Vietnam is correlated herein to the Meishan D section in China, the GSSP for the Permian–Triassic boundary. The first appearance datum of the conodont Hindeodus parvus at Meishan defines the Permian–Triassic boundary, and using published graphic correlation, the Permian–Triassic boundary level has been projected into the Lung Cam section. Using time-series analysis of magnetic susceptibility (χ) data, it is determined that H. parvus arrived at Lung Cam ∼18 kyr before the Permian–Triassic boundary. Data indicate that the Lung Cam section is expanded by ∼90 % relative to the GSSP section at Meishan. Given the expanded Lung Cam section, it is possible to resolve the timing of significant events during the Permian–Triassic transition with high precision. These events include major stepped extinctions, beginning at ∼135 kyr and ending at ∼110 kyr below the Permian–Triassic boundary, with a duration of ∼25 kyr, followed by deposition of Lung Cam ash Bed + 13, which is equivalent to Siberian Traps volcanism is graphically correlated to a precession Time-series model, placing onset of this major volcanic event at ~242 kyr before the PTB. The Meishan Beds 25 and 26, at ∼100 kyr before the Permian–Triassic boundary. In addition, the elemental geochemical, carbon and oxygen isotope stratigraphy, and magnetostratigraphy susceptibility datasets from Lung Cam allow good correlation to other Permian–Triassic boundary succession. These datasets are helpful when the conodont biostratigraphy is poorly known in sections with problems such as lithofacies variability, or is undefined, owing possibly to lithofacies exclusions, anoxia or for other reasons. The Lung Pu Permian–Triassic boundary section, ∼45 km from Lung Cam, is used to test these problems.

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Greig, C. J., and G. E. Gehrels. "U–Pb zircon geochronology of Lower Jurassic and Paleozoic Stikinian strata and Tertiary intrusions, northwestern British Columbia." Canadian Journal of Earth Sciences 32, no. 8 (August 1, 1995): 1155–71. http://dx.doi.org/10.1139/e95-095.

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New U–Pb zircon ages are reported from western Stikinia. Devonian and Pennsylvanian ages of volcanic rocks at Oweegee dome confirm the presence of pre-Permian strata, and with Paleozoic and Triassic detrital zircons from Lower Jurassic sandstone, they help to demonstrate pre-Lower Jurassic deformation and uplift. The absence of pre-Paleozoic inherited zircon from all samples is consistent with Nd–Sr isotopic data which suggest that Stikinia consists mainly of juvenile crust. U–Pb ages for posttectonic intrusions suggest that structures in Skeena Fold Belt in the Kinskuch area formed prior to Eocene time. Five ages for felsic volcanic rocks from stratigraphically well-constrained upper parts of the Hazelton arc are approximately 196–199 Ma and suggest near-contemporaneity for cessation of volcanism in the areas studied. The Sinemurian or late Sinemurian – early Pliensbachian ages are older than previously reported U–Pb and biostratigraphic ages for presumed correlative rocks to the west, and westward-migrating volcanism is implied. Together with Toarcian fossils from overlying sandstone, the new ages suggest that a hiatus of moderate duration preceded regionally extensive sedimentation.

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RACKI, GRZEGORZ. "End-Permian mass extinction: oceanographic consequences of double catastrophic volcanism." Lethaia 36, no. 3 (September 2003): 171–73. http://dx.doi.org/10.1080/00241160310003199.

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Soto-Kerans, Graham M., Daniel F. Stockli, Xavier Janson, Timothy F. Lawton, and Jacob A. Covault. "Orogen proximal sedimentation in the Permian foreland basin." Geosphere 16, no. 2 (January 6, 2020): 567–93. http://dx.doi.org/10.1130/ges02108.1.

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Abstract The sedimentary fill of peripheral foreland basins has the potential to preserve a record of the processes of ocean closure and continental collision, as well as the long-term (i.e., 107–108 yr) sediment-routing evolution associated with these processes; however, the detrital record of these deep-time tectonic processes and the sedimentary response have rarely been documented during the final stages of supercontinent assembly. The stratigraphy within the southern margin of the Delaware Basin and Marathon fold and thrust belt preserves a record of the Carboniferous–Permian Pangean continental assembly, culminating in the formation of the Delaware and Midland foreland basins of North America. Here, we use 1721 new detrital zircon (DZ) U-Pb ages from 13 stratigraphic samples within the Marathon fold and thrust belt and Glass Mountains of West Texas in order to evaluate the provenance and sediment-routing evolution of the southern, orogen-proximal region of this foreland basin system. Among these new DZ data, 85 core-rim age relationships record multi-stage crystallization related to magmatic or metamorphic events in sediment source areas, further constraining source terranes and sediment routing. Within samples, a lack of Neoproterozoic–Cambrian zircon grains in the pre-orogenic Mississippian Tesnus Formation and subsequent appearance of this zircon age group in the syn-orogenic Pennsylvanian Haymond Formation point toward initial basin inversion and the uplift and exhumation of volcanic units related to Rodinian rifting. Moreover, an upsection decrease in Grenvillian (ca. 1300–920 Ma) and an increase in Paleozoic zircons denote a progressive provenance shift from that of dominantly orogenic highland sources to that of sediment sources deeper in the Gondwanan hinterland during tectonic stabilization. Detrital zircon core-rim age relationships of ca. 1770 Ma cores with ca. 600–300 Ma rims indicate Amazonian cores with peri-Gondwanan or Pan-African rims, Grenvillian cores with ca. 580 Ma rims are correlative with Pan-African volcanism or the ca. 780–560 Ma volcanics along the rifted Laurentian margin, and Paleozoic core-rim age relationships are likely indicative of volcanic arc activity within peri-Gondwana, Coahuila, or Oaxaquia. Our results suggest dominant sediment delivery to the Marathon region from the nearby southern orogenic highland; less sediment was delivered from the axial portion of the Ouachita or Appalachian regions suggesting that this area of the basin was not affected by a transcontinental drainage. The provenance evolution of sediment provides insights into how continental collision directs the dispersal and deposition of sediment in the Permian Basin and analogous foreland basins.

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Cui, Ying, Mingsong Li, Elsbeth E. van Soelen, Francien Peterse, and Wolfram M. Kürschner. "Massive and rapid predominantly volcanic CO2 emission during the end-Permian mass extinction." Proceedings of the National Academy of Sciences 118, no. 37 (September 7, 2021): e2014701118. http://dx.doi.org/10.1073/pnas.2014701118.

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The end-Permian mass extinction event (∼252 Mya) is associated with one of the largest global carbon cycle perturbations in the Phanerozoic and is thought to be triggered by the Siberian Traps volcanism. Sizable carbon isotope excursions (CIEs) have been found at numerous sites around the world, suggesting massive quantities of 13C-depleted CO2 input into the ocean and atmosphere system. The exact magnitude and cause of the CIEs, the pace of CO2 emission, and the total quantity of CO2, however, remain poorly known. Here, we quantify the CO2 emission in an Earth system model based on new compound-specific carbon isotope records from the Finnmark Platform and an astronomically tuned age model. By quantitatively comparing the modeled surface ocean pH and boron isotope pH proxy, a massive (∼36,000 Gt C) and rapid emission (∼5 Gt C yr−1) of largely volcanic CO2 source (∼−15%) is necessary to drive the observed pattern of CIE, the abrupt decline in surface ocean pH, and the extreme global temperature increase. This suggests that the massive amount of greenhouse gases may have pushed the Earth system toward a critical tipping point, beyond which extreme changes in ocean pH and temperature led to irreversible mass extinction. The comparatively amplified CIE observed in higher plant leaf waxes suggests that the surface waters of the Finnmark Platform were likely out of equilibrium with the initial massive centennial-scale release of carbon from the massive Siberian Traps volcanism, supporting the rapidity of carbon injection. Our modeling work reveals that carbon emission pulses are accompanied by organic carbon burial, facilitated by widespread ocean anoxia.

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Ferri, Filippo. "Nina Creek Group and Lay Range Assemblage, north-central British Columbia: remnants of late Paleozoic oceanic and arc terranes." Canadian Journal of Earth Sciences 34, no. 6 (June 1, 1997): 854–74. http://dx.doi.org/10.1139/e17-070.

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In north-central British Columbia, a belt of upper Paleozoic volcanic and sedimentary rocks lies between Mesozoic arc rocks of Quesnellia and Ancestral North America. These rocks belong to two distinct terranes: the Nina Creek Group of the Slide Mountain terrane and the Lay Range Assemblage of the Quesnel terrane. The Nina Creek Group is composed of Mississippian to Late Permian argillite, chert, and mid-ocean-ridge tholeiitic basalt, formed in an ocean-floor setting. The sedimentary and volcanic rocks, the Mount Howell and Pillow Ridge successions, respectively, form discrete, generally coeval sequences interpreted as facies equivalents that have been interleaved by thrusting. The entire assemblage has been faulted against the Cassiar terrane of the North American miogeocline. West of the Nina Creek Group is the Lay Range Assemblage, correlated with the Harper Ranch subterrane of Quesnellia. It includes a lower division of Mississippian to Early Pennsylvanian sedimentary and volcanic rocks, some with continental affinity, and an upper division of Permian island-arc, basaltic tuffs and lavas containing detrital quartz and zircons of Proterozoic age. Tuffaceous horizons in the Nina Creek Group imply stratigraphic links to a volcanic-arc terrane, which is inferred to be the Lay Range Assemblage. Similarly, gritty horizons in the lower part of the Nina Creek Group suggest links to the paleocontinental margin to the east. It is assumed that the Lay Range Assemblage accumulated on a piece of continental crust that rifted away from ancestral North America in the Late Devonian to Early Mississippian by the westward migration of a west-facing arc. The back-arc extension produced the Slide Mountain marginal basin in which the Nina Creek Group was deposited. Arc volcanism in the Lay Range Assemblage and other members of the Harper Ranch subterrane was episodic rather than continuous, as was ocean-floor volcanism in the marginal basin. The basin probably grew to a width of hundreds rather than thousands of kilometres.

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Joachimski, M. M., A. S. Alekseev, A. Grigoryan, and Yu A. Gatovsky. "Siberian Trap volcanism, global warming and the Permian-Triassic mass extinction: New insights from Armenian Permian-Triassic sections." GSA Bulletin 132, no. 1-2 (June 17, 2019): 427–43. http://dx.doi.org/10.1130/b35108.1.

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Abstract Permian-Triassic boundary sections from Armenia were studied for carbon isotopes of carbonates as well as oxygen isotopes of conodont apatite in order to constrain the global significance of earlier reported variations in the isotope proxies and elaborate the temporal relationship between carbon cycle changes, global warming and Siberian Trap volcanism. Carbon isotope records of the Chanakhchi and Vedi II sections show a 3–5‰ negative excursion that start in the Clarkina nodosa (C. yini) conodont Zone (latest Permian) with minimum values recorded in Hindeodus parvus to Isarcicella isarcica conodont zones (earliest Triassic). Sea surface temperatures (SST) reconstructed from oxygen isotopes of conodont apatite increase by 8–10 °C over an extrapolated time interval of ∼39 ka with the onset of global warming occurring in the C. iranica (C. meishanensis) Zone of the latest Permian. Climate warming documented in the Armenian sections is comparable to published time-equivalent shifts in SST in Iran and South China suggesting that this temperature change represents a true global signature. By correlating the Armenian and Iranian section with the radiometrically well-dated Meishan GSSP (Global Stratotype Section and Point) section (South China), the negative shift in δ13C is estimated to have occurred 12–128 ka prior to the onset of global warming. This temporal offset is unexpected given the synchrony in changes in atmospheric CO2 and global temperature as seen in Pleistocene ice core records. The negative δ13C excursion is explained by the addition of emission of isotopically light CO2 and CH4 from thermogenic heating of organic carbon-rich sediments by Siberian Trap sill intrusions. However, the observed time lag in the δ13C and δ18O shifts questions the generally assumed cause-effect relationship between emission of thermogenically produced greenhouse gases and global warming. The onset of temperature rise coincides with a significant enrichment in Hg/TOC (total organic carbon) ratios arguing for a major volcanic event at the base of the extinction interval. Whether global warming was a major factor for the Late Permian mass extinction depends on the duration of the extinction interval. Warming only starts at the base of the extinction interval, but with the extinction encompassing a time interval of 60 ± 48 ka, global climate warming in conjunction with temperature-related stressors as hypoxia and reduced nutrient availability may have been one of the major triggers of the most devastating biotic crisis in Earth history.

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Rodríguez García, Gabriel, and Gloria Obando. "Volcanism of the La Quinta Formation in the Perijá mountain range." Boletín Geológico, no. 46 (June 30, 2020): 51–94. http://dx.doi.org/10.32685/0120-1425/boletingeo.46.2020.535.

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This study reports new data on the petrography, total rock chemistry and U-Pb zircon geochronology of volcanic rocks of the La Quinta Formation that outcrop the western flank of the Perijá mountain range and the Cesar and La Guajira departments. The volcanic rocks consist of basaltic, andesitic, dacitic and rhyolitic lavas, and the volcaniclastic rocks consist of crystal-vitric and crystal-lithic tuffs and agglomerates of calc-alkaline affinity, formed in a continental margin arc setting. Geochronological data suggest that the La Quinta Formation was volcanically active for approximately 25 Ma, during which its composition varied from basaltic trachyandesites to rhyolites. U-Pb dating suggests that the volcanism began in approximately 191 Ma (Sinemurian age) and continued until approximately 164 Ma, with at least three periods of increased volcanic activity. The inherited zircons contain Triassic, Permian, Neoproterozoic and Mesoproterozoic populations, indicating that this arc was emplaced on rocks of the Chibcha Terrane along the South American paleomargin and that it is part of the same arc that formed the Jurassic volcanic rocks of the Sierra Nevada de Santa Marta, Cocinas and San Lucas mountain ranges and the Upper Magdalena Valley.

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Nelson, D. A., and J. M. Cottle. "Tracking voluminous Permian volcanism of the Choiyoi Province into central Antarctica." Lithosphere 11, no. 3 (March 29, 2019): 386–98. http://dx.doi.org/10.1130/l1015.1.

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SAUNDERS, ANDREW D. "Two LIPs and two Earth-system crises: the impact of the North Atlantic Igneous Province and the Siberian Traps on the Earth-surface carbon cycle." Geological Magazine 153, no. 2 (June 9, 2015): 201–22. http://dx.doi.org/10.1017/s0016756815000175.

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AbstractThe links between the Siberian Traps and the end-Permian mass extinction, and between the North Atlantic igneous province (NAIP) and the Paleocene–Eocene thermal maximum (PETM), demonstrate a critical role for large igneous provinces (LIPs) in the disruption of the Earth-surface carbon cycle (ESCC). High-precision ages for both volcanic provinces and the associated environmental crises show that, in both cases, the crisis was contemporaneous with the volcanism. The NAIP comprises two phases: the earlier Phase 1 (c. 61 Ma) and the much more voluminous Phase 2 (c. 56 Ma), linked to the opening of the NE Atlantic. The latter triggered the PETM, the largest Cenozoic hyperthermal. The Siberian Traps are significantly more voluminous than the NAIP, and triggered the end-Permian mass extinction. The masses of volcanic CO2emitted from these provinces may have been much greater than previously suggested as substantial gas may come from intrusive bodies deep within the crust. Precursory warming due to the accumulation of volcanic CO2in the atmosphere likely triggered the release of low-δ13C methane hydrate, although the masses of methane hydrate alone may have been insufficient to account for the observed temperature rises. The organic C was likely strongly supplemented by magmatically derived carbon and thermogenic carbon released during emplacement of sills and dykes into C-rich sedimentary units. More data are required on the volcanic flux rates in order to refine the cause–effect relationships between LIPs and the ESCC.

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Spalletti, Luis A., and Carlos O. Limarino. "The Choiyoi magmatism in south western Gondwana: implications for the end-permian mass extinction - a review." Andean Geology 44, no. 3 (September 29, 2017): 328. http://dx.doi.org/10.5027/andgeov44n3-a05.

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The end of the Permian period is marked by global warming and the biggest known mass extinction on Earth. The crisis is commonly attributed to the formation of large igneous provinces because continental volcanic emissions have the potential to control atmospheric carbon dioxide (CO2) levels and climate change. We propose that in southwestern Gondwana the long-term hothouse Permian environmental conditions were associated with the development of the Choiyoi magmatism. This large igneous province was developed between the Cisuralian and the early Triassic. It covers an area estimated at 1,680,000 km2 with an average thickness of 700 m, so that the volume of effusive and consanguineous rocks is estimated at 1,260,000 km3. Towards the western sector of the study region, a major overlap exists between the regional development of the Choiyoi magmatism and the Carboniferous sedimentary basins, which include paralic and continental deposits with intercalations of peat and coal beds. Commonly, these upper Palaeozoic deposits accumulated on a thick substrate composed of Cambro-Ordovician carbonates and Ordovician to Devonian terrigenous sedimentary rocks characterised by a large proportion of dark organic-rich shales and turbidite successions. While extensive volcanism released large masses of carbon dioxide into the Permian atmosphere, the heating of Palaeozoic organic-rich shales, peat and carbonates by ascending magma led to CO2 and CH4 gas generation in sufficient volumes to amplify the major climatic change. The analysis of the almost continuous record of Permian redbeds in the Paganzo basin, where the Choiyoi magmatism is not recorded, allowed us to recognize two main pulses of strong environmental desiccation, one at the Cisuralian and the second around the end-Permian. These two drastic climatic crisis are attributed to peaks of CO2 and CH4 outbursts to the atmosphere and related collateral effects, such as acid rain, impoverishment of soils and increase in forest-fire frequency. We propose that the combination of these multiple mechanisms triggered the decline of biodiversity in southwestern Gondwana and caused the end-Permian extinction of most of the Glossopteridales.

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Lewandowska, Anna, Michał Banaś, and Karolina Zygoń. "K-Ar Dating of Amphiboles from Andesite of Complex Dyke in Dubie (Southern Poland)." Geochronometria 27, no. -1 (July 1, 2007): 11–15. http://dx.doi.org/10.2478/v10003-007-0016-z.

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K-Ar Dating of Amphiboles from Andesite of Complex Dyke in Dubie (Southern Poland) This study presents the results of radiometric K-Ar measurements on separated amphiboles from the andesite of the Dubie complex dyke. The data obtained cover the period of (291.3 ± 6.4) Ma, which corresponds to Carboniferous-Permian transition. The age is contemporaneous to the rhyodacitic and basaltoid volcanism of the Kraków region.

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Boutsougame, A., H. Ouazzani, E. H. Abba, and M. Alaoui. "Permian volcanism of the Khenifra Massif (Central Morocco) Petrography and geochemical affinity." IOP Conference Series: Earth and Environmental Science 1090, no. 1 (October 1, 2022): 012010. http://dx.doi.org/10.1088/1755-1315/1090/1/012010.

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Abstract The Permian volcanic complex of Khenifra (Moroccan Central Hercynian Massif) manifests itself mainly by volcanic rocks of andesite, rhyolite, dacite, rhyodacite, ignimbrite and trachyte nature. These are rocks with a microlitic to porphyritic texture. They are formed by a primary paragenesis made of plagioclase, pyroxene, olivine, feldspar, biotite, amphibole and quartz and a secondary mineral association made of augite, calcite, chlorite and opaque. Intermediate and acidic rocks are widely represented in Khenifra basin. These facies are of calco-alkaline affinity.

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Don Hermes, O., and Daniel P. Murray. "Middle Devonian to Permian plutonism and volcanism in the N American Appalachians." Geological Society, London, Special Publications 38, no. 1 (1988): 559–71. http://dx.doi.org/10.1144/gsl.sp.1988.038.01.38.

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Monaghan, A. A., and M. S. Pringle. "40Ar/39Ar geochronology of Carboniferous-Permian volcanism in the Midland Valley, Scotland." Geological Society, London, Special Publications 223, no. 1 (2004): 219–41. http://dx.doi.org/10.1144/gsl.sp.2004.223.01.10.

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Shen, Jun, Thomas J. Algeo, Qing Hu, Ning Zhang, Lian Zhou, Wenchen Xia, Shucheng Xie, and Qinglai Feng. "Negative C-isotope excursions at the Permian-Triassic boundary linked to volcanism." Geology 40, no. 11 (November 2012): 963–66. http://dx.doi.org/10.1130/g33329.1.

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Houghton, B. F., and C. A. Landis. "Sedimentation and volcanism in a Permian arc-related basin, southern New Zealand." Bulletin of Volcanology 51, no. 6 (September 1989): 433–50. http://dx.doi.org/10.1007/bf01078810.

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Zhong, Y. J., K. K. Huang, Y. F. Lan, and A. Q. Chen. "Simulation of Carbon Isotope Excursion Events at the Permian-Triassic Boundary Based on GEOCARB." Open Geosciences 10, no. 1 (September 14, 2018): 441–51. http://dx.doi.org/10.1515/geo-2018-0034.

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Abstract The biggest Phanerozoic mass extinctionoccurred at the Permian-Triassic boundary and resulted in the loss of about 95% or more of all marine species. For quite some time, many kinds of abnormal environmental events were adopted to explain the abnormal reduction of carbon isotope at the Permian-Triassic boundary, however there still has not been a unified opinion. In this paper, based on the carbon cycle balance model of the earth under a long-period scale, the contributions of possible cataclysm events at the Permian-Triassic boundary to the carbon isotope records in carbonates were quantitatively simulated. The results proved that a single event, such as volcanism, terrestrial ecosystem collapse or another factor, was not strong enough to lead to the negative bias of carbon isotope at the Permian-Triassic boundary. Even though the release of methane hydrate can result in a comparably large negative excursion of inorganic carbon, this explanation becomes unsuitable when both the shifting Permian-Triassic boundary and the fluctuation record of other inorganic carbon isotopes in the early Triassic as a whole are considered. Therefore, it is suggested that the dynamic equilibrium between inorganic carbon reserves and organic carbon reserves was possibly disturbed by a superimposed effect of multiple events.

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Weissert, Helmut. "Mesozoic C-cycle perturbations and climate: evidence for increased resilience of the Cretaceous biosphere to greenhouse pulses." Canadian Journal of Earth Sciences 56, no. 12 (December 2019): 1366–74. http://dx.doi.org/10.1139/cjes-2018-0227.

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The Mesozoic C-isotope record traces the history of the global carbon cycle. Major perturbations of the carbon cycle triggered by extraordinary volcanic activity are recorded in negative spikes coupled with positive C-isotope excursions. Prominent examples are the C-isotope anomaly events at the Permian–Triassic boundary and at the Triassic–Jurassic boundary, in the Toarcian or in the Aptian. While the major volcanic pulses at the Permian–Triassic and Triassic–Jurassic boundaries are considered as the main trigger of mass extinctions, carbon cycle perturbations in the Jurassic and Cretaceous were not accompanied by comparable extreme changes in marine or terrestrial biota. The data suggest either that changes in degassing of large igneous provinces explain the difference in the biota’s response to perturbation or (and) that the resilience of the Mesozoic biosphere to volcanic pulses changed through time. It is hypothesized that two factors contributed to the increased resilience of the biosphere in the Late Mesozoic: (1) starting in the Middle Jurassic, pelagic carbonate developed into an important sink of CO2in the long-term carbon cycle, contributing to increased resilience of the carbon cycle to perturbations, and (2) increasing fragmentation of Pangea resulted in the establishment of a transequatorial current system coupled with equatorial upwelling. This circulation pattern was intensified during greenhouse pulses. Increased marine productivity and widespread basinal anoxia favoured burial of organic carbon. Increased resilience of the Cretaceous biosphere against volcanic activity may explain why Deccan Trap volcanism was no longer sufficient as a trigger of a mass extinction at the Cretaceous–Paleogene boundary.

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Bagherpour, Borhan, Hugo Bucher, Torsten Vennemann, Elke Schneebeli-Hermann, Dong-xun Yuan, Marc Leu, Chao Zhang, and Shu-Zhong Shen. "Are Late Permian carbon isotope excursions of local or of global significance?" GSA Bulletin 132, no. 3-4 (July 16, 2019): 521–44. http://dx.doi.org/10.1130/b31996.1.

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Abstract We present a new, biostratigraphically calibrated organic and inorganic C-isotope record spanning the basal Late Permian to earliest Triassic from southern Guizhou (Nanpanjiang basin, South China). After fluctuations of a likely diagenetic overprint are removed, three negative carbon isotope excursions (CIEs) persist. These include a short-lived CIE during the early Wuchiapingian, a protracted CIE ending shortly after the Wuchiapingian–Changhsingian Boundary, and a third CIE straddling the Permian–Triassic boundary. Comparison of our new C-isotope record with others from the same basin suggests that influences of local bathymetry and of the amount of buried terrestrial organic matter are of importance. Comparison with other coeval time series outside of South China also highlights that only the negative CIE at the Permian–Triassic boundary is a global signal. These differences can be explained by the different volumes of erupted basalts between the Late Permian Emeishan and the younger Siberian large igneous provinces and their distinct eruptive modalities. Emeishan volcanism was largely submarine, implying that sea water was an efficient buffer against atmospheric propagation of volatiles. The equatorial position of Emeishan was also an additional obstacle for volatiles to reach the stratosphere and benefit from an efficient global distribution. Consequently, the local significance of these CIEs calls into question global correlations based on C-isotope chemostratigraphy during the Late Permian. The timing of the Late Permian Chinese CIEs is also not reflected in changes in species diversity or ecology, unlike the sudden and global Permian–Triassic boundary crisis and subsequent Early Triassic upheavals.

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Ueno, Katsumi, Yoshihiro Mizuno, Xiangdong Wang, and Shilong Mei. "Artinskian conodonts from the Dingjiazhai Formation of the Baoshan Block, west Yunnan, southwest China." Journal of Paleontology 76, no. 4 (July 2002): 741–50. http://dx.doi.org/10.1017/s0022336000042001.

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Permian conodonts were recovered for the first time from the Dingjiazhai Formation, a well-known diamictite-bearing stratigraphic unit in the Gondwana-derived Baoshan Block in West Yunnan, Southwest China. The conodont fauna occurs in limestone units within the upper part of the formation and consists of Sweetognathus bucaramangus (Rabe), S. whitei (Rhodes), Mesogondolella bisselli (Clark and Behnken), and an unidentified ramiform element. Based on the known stratigraphic distribution of 5. bucaramangus (Rabe), the fauna is referable to the upper Sweetognathus whitei-Mesogondolella bisselli Zone, and thus is dated as middle Artinskian according to the current definition of the stage. The Dingjiazhai Formation is overlain paraconformably by the Woniusi Formation, which is represented mostly by basalts and basaltic volcaniclastics related to rifting volcanism during the separation of the Baoshan Block from Gondwanaland. The present discovery of conodonts from the upper part of the Dingjiazhai Formation reveals that the glaciogene diamictites in the Dingjiazhai Formation are older than middle Artinskian, and the inception of rifting volcanism of the Baoshan Block is later than middle Artinskian.Occurrence of an essentially warm water element, Sweetognathus bucaramangus (Rabe), in the Dingjiazhai conodont assemblage notwithstanding, the entire fossil faunas including brachiopods and fusulinoideans from the limestone units of the formation can be best interpreted as a middle latitudinal, non-tropical, and still substantially Gondwana-influenced assemblage developed at the northern margin of Gondwanaland just after deglaciation in the southern hemisphere during Early Permian time. This time could be regarded as the beginning of the Cimmerian Region, which had mixed or transitional paleobiogeographic characteristics between the Paleoequatorial Tethyan and cool/cold Gondwanan realms, and which became well developed during Middle Permian time.

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Fang, Qian, Hanlie Hong, Zhong-Qiang Chen, Jianxin Yu, Chaowen Wang, Ke Yin, Lulu Zhao, et al. "Microbial proliferation coinciding with volcanism during the Permian–Triassic transition: New, direct evidence from volcanic ashes, South China." Palaeogeography, Palaeoclimatology, Palaeoecology 474 (May 2017): 164–86. http://dx.doi.org/10.1016/j.palaeo.2016.06.026.

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Renne, P. R., M. T. Black, Z. Zichao, M. A. Richards, and A. R. Basu. "Synchrony and Causal Relations Between Permian-Triassic Boundary Crises and Siberian Flood Volcanism." Science 269, no. 5229 (September 8, 1995): 1413–16. http://dx.doi.org/10.1126/science.269.5229.1413.

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Chen, Jun, and Yi-gang Xu. "Establishing the link between Permian volcanism and biodiversity changes: Insights from geochemical proxies." Gondwana Research 75 (November 2019): 68–96. http://dx.doi.org/10.1016/j.gr.2019.04.008.

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Wignall, P. B., Y. Sun, D. P. G. Bond, G. Izon, R. J. Newton, S. Vedrine, M. Widdowson, et al. "Volcanism, Mass Extinction, and Carbon Isotope Fluctuations in the Middle Permian of China." Science 324, no. 5931 (May 28, 2009): 1179–82. http://dx.doi.org/10.1126/science.1171956.

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Isozaki, Yukio, Noriei Shimizu, Jianxin Yao, Zhansheng Ji, and Tetsuo Matsuda. "End-Permian extinction and volcanism-induced environmental stress: The Permian–Triassic boundary interval of lower-slope facies at Chaotian, South China." Palaeogeography, Palaeoclimatology, Palaeoecology 252, no. 1-2 (August 2007): 218–38. http://dx.doi.org/10.1016/j.palaeo.2006.11.051.

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Day, Michael O., Jahandar Ramezani, Samuel A. Bowring, Peter M. Sadler, Douglas H. Erwin, Fernando Abdala, and Bruce S. Rubidge. "When and how did the terrestrial mid-Permian mass extinction occur? Evidence from the tetrapod record of the Karoo Basin, South Africa." Proceedings of the Royal Society B: Biological Sciences 282, no. 1811 (July 22, 2015): 20150834. http://dx.doi.org/10.1098/rspb.2015.0834.

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A mid-Permian (Guadalupian epoch) extinction event at approximately 260 Ma has been mooted for two decades. This is based primarily on invertebrate biostratigraphy of Guadalupian–Lopingian marine carbonate platforms in southern China, which are temporally constrained by correlation to the associated Emeishan Large Igneous Province (LIP). Despite attempts to identify a similar biodiversity crisis in the terrestrial realm, the low resolution of mid-Permian tetrapod biostratigraphy and a lack of robust geochronological constraints have until now hampered both the correlation and quantification of terrestrial extinctions. Here we present an extensive compilation of tetrapod-stratigraphic data analysed by the constrained optimization (CONOP) algorithm that reveals a significant extinction event among tetrapods within the lower Beaufort Group of the Karoo Basin, South Africa, in the latest Capitanian. Our fossil dataset reveals a 74–80% loss of generic richness between the upper Tapinocephalus Assemblage Zone (AZ) and the mid- Pristerognathus AZ that is temporally constrained by a U–Pb zircon date (CA-TIMS method) of 260.259 ± 0.081 Ma from a tuff near the top of the Tapinocephalus AZ. This strengthens the biochronology of the Permian Beaufort Group and supports the existence of a mid-Permian mass extinction event on land near the end of the Guadalupian. Our results permit a temporal association between the extinction of dinocephalian therapsids and the LIP volcanism at Emeishan, as well as the marine end-Guadalupian extinctions.

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Schneider, J. "Environment, biotas and taphonomy of the Lower Permian lacustrine Niederhäslich limestone, Döhlen basin, Germany." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 84, no. 3-4 (1993): 453–64. http://dx.doi.org/10.1017/s0263593300006258.

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ABSTRACTA laminated, partly peloidal lacustrine limestone from the Lower Permian intermontane Döhlen basin in Saxony, Germany, contains one of the most diverse late Palaeozoic tetrapod faunas in Europe associated with a marine higher algal flora of Tethyan character. The surprising co-occurrence of these organisms and the lack of fishes is explained by the special position of this basin above the Elbe lineament, the influence of strong volcanism, of differentiated salinity in the lake and of the palaeowind systems, as well as by the action of stratigraphic, palaeogeographic and palaeoecological filters.

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Shen, Jun, Thomas J. Algeo, Noah J. Planavsky, Jianxin Yu, Qinglai Feng, Haijun Song, Huyue Song, Harry Rowe, Lian Zhou, and Jiubin Chen. "Mercury enrichments provide evidence of Early Triassic volcanism following the end-Permian mass extinction." Earth-Science Reviews 195 (August 2019): 191–212. http://dx.doi.org/10.1016/j.earscirev.2019.05.010.

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Zhang, Feng-Qi, Hong-Xiang Wu, Yildirim Dilek, Wei Zhang, Kong-Yang Zhu, and Han-Lin Chen. "Guadalupian (Permian) onset of subduction zone volcanism and geodynamic turnover from passive- to active-margin tectonics in southeast China." GSA Bulletin 132, no. 1-2 (May 14, 2019): 130–48. http://dx.doi.org/10.1130/b32014.1.

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Abstract New stratigraphic, geochemical, and geochronological data from the late Paleozoic depositional record in Anhui Province, China, signal the onset of active-margin magmatism in East Asia. Chert-shale sequences of the Gufeng Formation are part of a Carboniferous–Permian carbonate platform that developed along the passive margin of the South China block. Thin tuffaceous interlayers in these sequences represent distal ash deposits, marking discrete volcanic events. Sensitive high-resolution ion microprobe (SHRIMP) U-Pb zircon dating of the stratigraphically bottom and near-top tuffaceous interlayers has revealed crystallization ages of 270 Ma and 264 Ma, respectively, constraining the time span of subaerial eruptions to ∼6 m.y. during the Guadalupian Epoch. High SiO2 and Al2O3 contents, enrichments in large ion lithophile and light rare earth elements, and depletion patterns of high field strength and heavy rare earth elements indicate a calc-alkaline magma source in an arc setting for the origin of these volcanic tuff deposits. Detrital zircon geochronology of sandstones in the overlying Longtan Formation shows two prominent age populations of 290–250 Ma and 1910–1800 Ma. The former age cluster overlaps with the tightly constrained zircon ages obtained from the Gufeng Formation. The latter age group is compatible with the known magmatic-metamorphic ages from Cathaysia in the South China block, and it points to the existence of a NE-SW–trending topographic high as a major sediment source. We interpret this topographic high and silicic volcanism to represent an Andean-type active margin, developed above a north-dipping paleo-Pacific slab. Our tightly constrained Guadalupian eruption ages indicate the inception of magmatic arc construction and mark a major switch from passive- to active-margin tectonics along SE Asia.

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Vozárová, Anna, Patrik Konečný, Marek Vďačný, Jozef Vozár, and Katarína Šarinová. "Provenance of Permian Malužiná Formation sandstones (Hronicum, Western Carpathians): evidence from monazite geochronology." Geologica Carpathica 65, no. 5 (October 1, 2014): 329–41. http://dx.doi.org/10.2478/geoca-2014-0023.

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Abstract The Permian Malužiná Formation and the Pennsylvanian Nižná Boca Formation are Upper Paleozoic volcano- sedimentary complexes in the Hronicum nappe system. Sandstones, shales and conglomerates are the dominant lithological members of the Malužiná Formation sequence. Detrital monazites were analysed by electron microprobe, to obtain Th-U-Pb ages of the source areas. The majority of detrital monazites showed Devonian-Mississippian ages, ranging from 330 to 380 Ma with a weighted average of 351 ± 3.3 (2σ), that correspond well with the main phase of arcrelated magmatic activity in the Western Carpathians. Only a small portion of detrital monazites displayed Permian ages in the range of 250-280 Ma, with a significant maximum around 255 Ma. The weighted average corresponds to 255 ± 6.2 Ma. These monazites may have been partially derived from the synsedimentary acid volcanism that was situated on the margins of the original depositional basin. However, some of the Triassic ages (230-240 Ma), reflect, most likely, the genetic relationship with the overheating connected with Permian and subsequent Triassic extensional regime. Detrital monazite ages document the Variscan age of the source area and also reflect a gradual development of the Hronicum terrestrial rift, accompanied by the heterogeneous cooling of the lithosphere.

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Erlström, Mikael. "Chapter 24 Carboniferous–Neogene tectonic evolution of the Fennoscandian transition zone, southern Sweden." Geological Society, London, Memoirs 50, no. 1 (2020): 603–20. http://dx.doi.org/10.1144/m50-2016-25.

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AbstractThe Fennoscandian transition zone, including the Sorgenfrei–Tornquist Zone, constitutes the weakened and faulted bedrock between a craton, including the ancient continent Baltica to the north, and the boundary between Baltica and Avalonia along the Trans-European Fault Zone to the south. Early Permian subsidence in this transition zone resulted in the development of various basins and the initiation of a more or less continuous Permian–Paleogene depositional cycle. In southwestern Sweden, magmatic activity associated with transtensional deformation along the Sorgenfrei–Tornquist Zone prevailed during the Late Carboniferous–Permian. However, the transition zone is dominated by a Mesozoic sedimentary rock succession displaying both hiatuses and great lateral variability in composition and thickness, which can be related to several tectonic events including the progressive break-up of Pangaea. Much of the deposition took place in continental, coastal and shallow-marine settings. Early–Middle Jurassic block faulting and basanitic or melanephelinitic volcanism, as well as Late Cretaceous tectonic inversion along the Sorgenfrei–Tornquist Zone, related to a changeover to a predominantly compressive tectonic regime coeval with the Alpine orogeny, significantly influenced the depositional setting. Subsequent Paleogene–Neogene regional uplift of the southwestern margin of Baltica resulted in significant erosion of the bedrock.

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Kuznetsov, V. G., and L. M. Zhuravleva. "Geological and biological reasons for the collapse of reef formation, Paleozoic." Литология и полезные ископаемые, no. 2 (March 28, 2019): 119–29. http://dx.doi.org/10.31857/s0024-497x20192119-129.

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Paleozoic reef formation developed cyclically, and its global termination has been caused by the biological reasons — biotic crises and mass extinctions near the borders early and middle Cambrian, Ordovician and Silurian, Frasnian and Famennian, Serpukhovian and Bashkirian, Permian and Triassic. The Early Cambrian reef formation has ended along with disappearance of archaeocyathid. In the later stages reefs were much more difficult ecosystems, and they stopped developing before the full extinction of the reef-building communities. The interruption of reef formations within the separate stages have been connected with the geological and paleogeographic reasons – volcanism, regression, climate aridization etc.

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Liao, Zhiwei, Wenxuan Hu, Jian Cao, Xiaolin Wang, Suping Yao, Haiguang Wu, and Ye Wan. "Heterogeneous volcanism across the Permian–Triassic Boundary in South China and implications for the Latest Permian Mass Extinction: New evidence from volcanic ash layers in the Lower Yangtze Region." Journal of Asian Earth Sciences 127 (September 2016): 197–210. http://dx.doi.org/10.1016/j.jseaes.2016.06.003.

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Sadovnikov, G. N. "About Late Gagary-Ostrovian biota (Late Permian) at the North of the Siberian platform." Proceedings of higher educational establishments. Geology and Exploration, no. 1 (February 28, 2017): 22–29. http://dx.doi.org/10.32454/0016-7762-2017-1-22-29.

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Prior to the beginning of a trap volcanism of Central Siberia there was a plain, covered by Cordaitanthales. Slope herbaceous cover consisted mainly of ferns. Equisetopsida prevailed in the swampy lowlands. Volcanic eruptions at the end of Vishkilian (Severodvinian) led to the formation of a hill. It was covered by similar vegetation, but vegetation of herbaceous slopes substantially prevailed. Woody vegetation was dominated at only two locations, it was also about 50% at three locations and absent at two ones. Associations of the grassy slopes in most places were at least 46%, they were about 100% in two places and absent in 42% of the places. Ferns dominated sharply. Todites (?) anthriscifolia, Todites (?) sibirica, Prynadaeopteris (?) karpovii, rarely Cladophlebis aff. taimyrensis were dominants. Sometimes Prynadaeopteris (?) venusta were codominants. Yavorskyia radczenkovii sometimes codominated among gymnosperms. The herbaceous cover of the lowlands was dominated by Equisetopsida. At two locations, they are about 100%, and more than 50% at two ones , and from 12 to 33% at four ones. They are absent only at two localities. Paracalamites were usually dominants. Sometimes hyllotheca turnaensis, P. minuta, Paraschizoneura codominated. In the basins, Palaeoanodonta (Bivalve) had a significant role. Thus, the composition of the flora of the Late Gagary-Ostrovian time has a little difference from the Early Gagary-Ostrovian, but the ecological differences are significant. Forest communities are inferior to the dominant role of herbaceous slopes ones. This makes the flora of the Late Gagary-Ostrovian time be similar to the followed Tutonchanian - Early Dvurogyan flora in the ecological sense.

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Hongfu, Yin, Huang Siji, Zhang Kexin, Yang Fengqing, Ding Meihua, Bi Xianmei, and Zhang Suxin. "Volcanism at the Permian-Triassic Boundary in South China and Its Effects on Mass Extinction." Acta Geologica Sinica - English Edition 2, no. 4 (May 29, 2009): 417–31. http://dx.doi.org/10.1111/j.1755-6724.1989.mp2004007.x.

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Lu, Jianlin, Zongxin Zuo, Zheng Shi, Xia Dong, Qingjie Wu, and Xiaobo Song. "Characteristics of Permian volcanism in the western Sichuan Basin and its natural gas exploration potential." Natural Gas Industry B 6, no. 5 (October 2019): 444–51. http://dx.doi.org/10.1016/j.ngib.2019.02.002.

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Journal articles on the topic 'Permian volcanism'

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