Hydrothermal dissolution of deep-buried carbonate rocks and its significance for hydrocarbon exploration in Shunnan area, the Tarim Basin: taking well Peng-1 in Shunnan area as a c... by Jun HAN, Shaofeng DONG, Donghua YOU, Sheng ZHANG, Chongyang XIAO, Yingming WANG

“…Based on detailed core observation and description, it was found that the dissolution pores were mainly distributed in the Upper Cambrian dolomites in the lower part of the core section and few in the Lower Ordovician carbonates in the upper part of the core section. …”
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Carência de magnésio em castanheiro: influência do manganês do solo Magnesium deficiency in chestnut: the influence of soil manganese by Portela Ester, Carlos Coelho-Pires, José Louzada

“…In soils with the highest contents of Mn (>200 mg kg-1) the chestnut groves were established on Mn-rich schists and greywackes of the Ordovician and the Silurian.…”
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The Late Cambrian to Neogene Evolution of the Khanom Core Complex (Peninsular Thailand) by Urs S. Klötzli, Bernhard Neugschwentner, Jolanta Burda, Pitsanupong Kanjanapayont, Qiu-Li Li, Yu Liu, Patrik Konečný, Punya Charusiri

“…A syn- to postsedimentary andesitic intrusion/extrusion in the Haad Nai Phlao complex at 495 ± 10 Ma defines a minimum age for the former event(s). In the Early Ordovician (477 ± 7 Ma), the Haad Nai Phlao complex and the Khao Yoi paragneisses were intruded by the Khao Dat Fa granite. …”
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Numerical modeling of in-situ stress and prediction of favorable area of shale gas layer in Wufeng to Longmaxi formations, Nanchuan region, southeastern Chongqing by Ming LIU, Ruiqing YANG, Fengli YANG, Haojuan LIU, Zhiping ZHANG, Wei WANG, Panpan HU

“…Upper Ordovician Wufeng to Lower Silurian Longmaxi formations in Nanchuan region, as an important shale gas productive layer, is characterized by large shale thickness, deep burial depth, and complex in-situ stress with rapid direction changes. …”
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Characteristics and Differences Analysis for Thermal Evolution of Wufeng–Longmaxi Shale, Southern Sichuan Basin, SW China by Peixi Lyu, Jianghui Meng, Renfang Pan, Xuefei Yi, Tao Yue, Ning Zhang

“…The marine shale of the Upper Ordovician Wufeng Formation–Lower Silurian Longmaxi Formation is the main source rock and the target of shale gas exploration in the southern Sichuan Basin. …”
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Stable Bromine Isotopic Composition of Coal Bed Methane (CBM) Produced Water, the Occurrence of Enriched ⁸¹Br, and Implications for Fluid Flow in the Midcontinent, USA by Randy L. Stotler, Matthew F. Kirk, K. David Newell, Robert H. Goldstein, Shaun K. Frape, Rhys Gwynne

“…Both fluid groups have geochemical similarities to fluids in Cambrian, Ordovician, and Mississippian units. Lower salinity and higher temperature fluids from deeper units are leaking up into the Cherokee Group and mixing with a higher salinity fluid with higher δ⁸¹Br and more radiogenic ⁸⁷Sr/⁸⁶Sr. …”
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Evolution of arc magmatic cycles from the Carboniferous to the Early Cretaceous in the western paleomargin of Gondwana, north of the Andes by Gabriel Rodríguez García, Ana María Correa Martínez, Juan Pablo Zapata, Diego Armando Ramírez, Carlos Andrés Sabrica

“…To the west, off the continental margin, a new arc magmatic cycle began over a different continental terrane ca. 171 Ma and extended to ca. 138 Ma, giving rise to a belt of calcic to calcic-alkaline plutons emplaced in the Ordovician metamorphic (Anacona Terrane), Triassic (Tahamí Terrane), and Upper Jurassic (Tierradentro Orogen) rocks. …”
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Zn-Pb-Cu sulfide-bearing glacial sandstone erratics near Raahe on the western coast of Finland: Indicators of Paleozoic base metal mineralization at the bottom of the Bothnian Bay by Eero Hanski, Hannu Huhma, Yann Lahaye, Juha Pekka Lunkka, Erik Nilsson, Timo Mäki, Hugh O´Brien, Kari Strand

“…These compositions are similar to those measured for the Laisvall MVT Pb-Zn deposit in the Swedish Caledonides, being consistent with a similar Ordovician age of ore formation. However, S isotope analyses yielded heterogeneous compositions, with pyrite showing mostly negative δ34S values from −15.6 to −7.6‰, indicating partly a strong bacteriogenic signature, which are distinctly different from the generally heavy sulfur isotope compositions (avg. δ34S +24‰) reported from the Laisvall-type deposits, pointing to a different source of sulfur. …”
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Water inrush and failure characteristics of coal seam floor over a confined aquifer by Min Cao, Shangxian Yin, Bin Xu

“…As the mining depth increases, the coal seam is getting closer to the Ordovician Limestone. This study provides an improved understand and theoretical support for the safe mining of coal seams under similar conditions.…”
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Resource potential, exploration prospects, and favorable direction for natural gas in deep formations in China by Jingdu Yu, Min Zheng, Jianzhong Li, Xiaozhi Wu, Qiulin Guo

“…In these basins, the favorable directions to further exploration for natural gas in deep formations are acquired as the clastic and volcanic reservoir from Jurrasic to Cretaceous system formed in the fault depression group of Songliao basin, the dolomite reservoir of the lithological facie as mound and shoal in the center of paleo-uplift in Sichuan Basin, bioclastic limestone and dolomite reservoir in the facies of reef flat contained in Changxing and Feixianguan formation in the north and northwest of Sichuan Basin, The dolomite reservoir from Devonian to lower Permian in the west of Sichuan Basin, the Ordovician dolomite reservoir in the facies of mound and shoal in the center of Tarim Basin, and Cretaceous clastic reservoir in Kuche depression of Tarim basin, etc., which consequently reveals the prominent prospect for natural gas contained in deep formations. …”
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Ophiolites of the Central Asian Orogenic Belt: Geochemical and petrological characterization and tectonic settings by Harald Furnes, Inna Safonova

“…The Neoproterozoic and Ordovician complexes exhibit the highest, whereas those of Silurian age exhibit the lowest subduction-influence. …”
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Insights on high-grade deformation in quartzo-feldspathic gneisses during the early Variscan exhumation of the Cabo Ortegal nappe, NW Iberia by F. J. Fernández, S. Llana-Fúnez, P. Valverde-Vaquero, A. Marcos, P. Castiñeiras

“…The rock sequence formed by migmatitic quartzo-feldspathic (qz-fsp) gneisses and mafic rocks records the early Ordovician (ca. 480–488 Ma) injection of felsic dioritic/granodioritic dykes at the base of the qz-fsp gneisses, and Devonian eclogitization (ca. 390.4 ± 1.2 Ma), prior to its exhumation. …”
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Muenstraia, ein neues Rugosa-Genus (Anthozoa) aus dem Obersilur und Unterdevon by D. Weyer

“…The genus descends from the isolated Upper Middle Ordovician Protozaphrentis Yü, 1957, only known from Xinjiang in China; it is the ancestor of two new phylogenetic lines starting in the Ludlovian with Laccophyllum Simpson, 1900, and Sutherlandinia Weyer, 1972.Morphology and diagnosis are identical with the (since Schindewolf 1931) traditional definition of the genus Petraia Münster, 1839, which represents according to a revision of its real and Upper Famennian type species Petraia decussata Münster, 1839 (Weyer 2000) another phylogenetic line (Neaxoninae Hill, 1981, now Petraiidae Koninck, 1872). …”
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Early-Late Devonian Post-Collision Extension Due to Slab Breakoff Regime along the Northern Margin of North China Craton: Implications from Muscovite ⁴⁰Ar-³⁹A... by Changhai Li, Shichao Li, Zhenghong Liu, Zhongyuan Xu, Xiaojie Dong, Qiang Shi, Shijie Wang, Fan Feng

“…Ordovician-Silurian subduction, Early Devonian arc-contient collision and followed post-collision extension are recorded in the north of the North China Craton. …”
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The structural geometry, metamorphic and magmatic evolution of the Everest massif, Nepal and South Tibet by Searle, M, Simpson, R, Law, R, Parrish, R

“…The upper fault, the Qomolangma detachment (QD), separates the Everest series greenschists below from the unmetamorphosed Ordovician sediments above. On the SW face of Everest in Nepal, the greenschists are ca. 2000 m thick, but to the north, along the Rongbuk glacier in Tibet the two faults converge into one large shear zone. …”

Geochemistry, zircon U-Pb age and Hf isotope for the Huatugou granitoid in western Qaidam: Petrogenesis and tectonic implications by Xia Teng, Xia Teng, Jianxin Zhang, Xiaohong Mao, Yawei Wu, Yawei Wu, Qi Guo, Qi Guo

“…The Qaidam Precambrian block is located in the northeastern Tibetan Plateau and was intruded by numerous Ordovician-Devonian granitoids during and after the closure of the Proto-Tethys Ocean. …”
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New data on the composition and age of gabbro-dolerites of the Oyu complex of the Yambpe Ridge, north-west Pai-Khoi by P. S. Zhegunov, E. V. Starikova, D. A. Petrov, P. A. Lvov

“…The intrusions are located in the Middle-Late Ordovician sequences of the Khengur and Talbeytyvis formations and uncover in the Yamb-Pe structures and the right bank of the Bol’shaya Oyu river. …”
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Hydrochemical and Isotopic Difference of Spring Water Depending on Flow Type in a Stratigraphically Complex Karst Area of South Korea by Soonyoung Yu, Gitak Chae, Junseop Oh, Se-Hoon Kim, Dong-Il Kim, Seong-Taek Yun

“…A combined use of hydrochemical, environmental isotopic, and hydrograph separation study was performed to understand the subsurface flow in a karst terrain where Ordovician carbonate rocks overlie Jurassic sandstone and shale along thrusts. …”
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Petrology, u-pb isotope age and metamorphism of nyashevo polygenic mafit-ultramafite massive (the southern urals) by Natal’ya M. Valizer, Artur A. Krasnobaev, Anatolii I. Rusin, Natal’ya M. Murdasova

“…The formations of Nyashevo massif is the age of the Late Ordovician (443 ± 12 Ma) and almost coincides with the maximum marks of age Buldym ultramafic alkaline-carbonatite massif. …”
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Relationship between geological structure and marine shale gas preservation conditions in the western Middle Yangtze Block by Kongquan Chen, Douzhong Zhang, Xiusong Tuo

“…In conclusion, shale gas preservation conditions of Upper Ordovician Wufeng Formation–Lower Silurian Longmaxi Formation in this area are the best in Zigui syncline, thrust–detachment zone and western margin of Qiyueshan fault. …”
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