Terra NovaPub Date : 2024-06-26DOI: 10.1111/ter.12733
Valentin R. Troll, Frances M. Deegan, Thor Thordarson, Ari Tryggvason, Lukáš Krmíček, William M. Moreland, Björn Lund, Ilya N. Bindeman, Ármann Höskuldsson, James M. D. Day
{"title":"The Fagradalsfjall and Sundhnúkur Fires of 2021–2024: A single magma reservoir under the Reykjanes Peninsula, Iceland?","authors":"Valentin R. Troll, Frances M. Deegan, Thor Thordarson, Ari Tryggvason, Lukáš Krmíček, William M. Moreland, Björn Lund, Ilya N. Bindeman, Ármann Höskuldsson, James M. D. Day","doi":"10.1111/ter.12733","DOIUrl":"https://doi.org/10.1111/ter.12733","url":null,"abstract":"The Reykjanes Peninsula (RP) hosts several volcanic lineaments that have been periodically active over the last 4000 years. Since 2021, following a ca. 800‐year quiescence, eight eruptions have occurred on the RP, with more expected in the future. To better understand the origins of this renewed volcanism and help forecast future eruptions, we examine (i) if the ongoing volcanism is fed from a single or multiple magma storage zone(s) or from several smaller reservoirs and; (ii) where the zone(s) are located (i.e. mantle or lower or upper crustal depths). Using major and trace element geochemistry, oxygen isotopes, and seismic tomography we rule out a single, RP‐scale, deep‐seated magma storage zone. Instead we propose the presence of a ca. 10‐km‐wide region of crustal‐level (9–12 km) magma accumulation beneath the Fagradalsfjall volcanic lineament that fed both the 2021–23 eruptions of the Fagradalsfjall Fires and the 2023–24 eruptions of the Sundhnúkur Fires.","PeriodicalId":22260,"journal":{"name":"Terra Nova","volume":"745 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141529694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Terra NovaPub Date : 2024-06-22DOI: 10.1111/ter.12736
Tengfei Wu, Chenyang Zou, Yujin Hua, Meng Chen
{"title":"Ambient noise tomography reveals complex crustal structure beneath eastern and northeastern Tibet: Insight‐ into regional crustal flow","authors":"Tengfei Wu, Chenyang Zou, Yujin Hua, Meng Chen","doi":"10.1111/ter.12736","DOIUrl":"https://doi.org/10.1111/ter.12736","url":null,"abstract":"We present a 3‐D crustal S‐wave velocity (Vs) model for eastern and northeastern Tibet utilizing ambient noise tomography. Our model reveals that crustal flow channels are absent in northeastern Tibet. In this region, the Kunlun Fault (KLF) significantly impacts mid‐lower crust low‐Vs anomalies. In addition, isolated low‐Vs anomalies beneath the Qilian orogeny are unrelated to the low‐Vs materials of the Tibetan Plateau. In the mid‐lower crust of the Songpan‐Ganzi terrane, its northeastern corner exhibits continuous low‐Vs anomalies, limited to areas south of the West Qinglin and west of 104° E. This suggests that a small‐scale northward viscous flow of crustal materials exists in the eastern KLF. However, two significant crustal flow channels (<jats:italic>V</jats:italic>s ≤ 3.3 km/s) are observed in eastern Tibet. The east–west tectonic movements and the obstruction of the Sichuan Basin together facilitate the dispersion of crustal materials southward from eastern Tibet.","PeriodicalId":22260,"journal":{"name":"Terra Nova","volume":"146 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141529695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Terra NovaPub Date : 2024-06-20DOI: 10.1111/ter.12734
Jean‐Claude Hippolyte, Paul Mann, Pierre Henry, Abel Guihou, Pierre Deschamps, Camille Ourliac, Nicolas Godeau, Lionnel Marié, Mark B. Gordon
{"title":"U–Pb calcite dating reveals the origin of a 600 km‐long intraplate fault: The Balcones Fault System of Texas","authors":"Jean‐Claude Hippolyte, Paul Mann, Pierre Henry, Abel Guihou, Pierre Deschamps, Camille Ourliac, Nicolas Godeau, Lionnel Marié, Mark B. Gordon","doi":"10.1111/ter.12734","DOIUrl":"https://doi.org/10.1111/ter.12734","url":null,"abstract":"Timing is a key data for understanding the origin of faulting. The Balcones fault system (BFS) extends ~600 km along the northern margin of the Gulf of Mexico oil basin and controls springs that supply the major cities in Texas, but its origin is unclear. We provide its first direct timing by applying U–Pb geochronology on seven calcite‐mineralized fault surfaces. We have found that this extensional fault system formed during the Palaeocene‐middle Eocene time (from 61.3 ± 2.7 to 45.4 ± 2.1 Ma), which is much earlier than previous estimates. We show that the formation of the BFS coincides with the largest clastic influx in the northern Gulf of Mexico basin that resulted from Laramide uplift and erosion. This timing and the location of the BFS along the Ouachita suture, support our interpretation of this fault system formed as the result of lithospheric flexure related to Paleogene sedimentary loading.","PeriodicalId":22260,"journal":{"name":"Terra Nova","volume":"347 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141508453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Terra NovaPub Date : 2024-05-29DOI: 10.1111/ter.12732
Kui Tong, Jinxi Li, Zhiwu Li, I. Tonguç Uysal, Jianxin Zhao, Yuexing Feng, Tian Hua, Shugen Liu
{"title":"In‐situ U‐Pb dating of calcite slickenfibre constraints on Cenozoic multiple‐phase faulting along the eastern segment of Chengkou Fault, Dabashan Fold‐and‐Thrust Belt","authors":"Kui Tong, Jinxi Li, Zhiwu Li, I. Tonguç Uysal, Jianxin Zhao, Yuexing Feng, Tian Hua, Shugen Liu","doi":"10.1111/ter.12732","DOIUrl":"https://doi.org/10.1111/ter.12732","url":null,"abstract":"The Dabashan Fold‐and‐Thrust Belt is an important natural laboratory for exploring the Meso‐Cenozoic intracontinental orogenic evolution in China. Due to the severe lack of post‐Early Cretaceous strata, little attention has been paid to Cenozoic tectonic in the Dabashan. This study presents structural analysis, in‐situ U‐Pb dating of calcite in conjunction with petrographic and stable isotopic analyses along the eastern segment of the Chengkou Fault in the Dabashan. Structural analysis coupled with U‐Pb dating of syn‐kinematic calcite slickenfibres suggests two discrete S‐N compressional strike‐slip deformation events associated with localized E‐W extension along the eastern segment of the Chengkou Fault have occurred at the Early Eocene (~57–50 Ma) and Late Oligocene‐Early Miocene (~23–17 Ma), respectively. We tentatively related the Cenozoic deformation events in the study area to the clockwise rotation of the Sichuan Basin, resulting from the combined far‐field stress effects between the India, Eurasia and western Pacific plates.","PeriodicalId":22260,"journal":{"name":"Terra Nova","volume":"13 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141192196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Terra NovaPub Date : 2024-05-25DOI: 10.1111/ter.12725
Y. Raghumani Singh, A. Bijayalaxmi Devi, Nithoujam Surdas Singh, Mark B. Abbott, T. Elliot Arnold, W. Ajoykumar Singh, M. Sapana Devi, Sh. Priyokumar Singh, O. Victory Devi
{"title":"Dinoflagellate cysts from the Shillong Plateau, Meghalaya (India): Palynological signature during the late Palaeocene–early Eocene Transition","authors":"Y. Raghumani Singh, A. Bijayalaxmi Devi, Nithoujam Surdas Singh, Mark B. Abbott, T. Elliot Arnold, W. Ajoykumar Singh, M. Sapana Devi, Sh. Priyokumar Singh, O. Victory Devi","doi":"10.1111/ter.12725","DOIUrl":"https://doi.org/10.1111/ter.12725","url":null,"abstract":"The paper presents a new section of the late Palaeocene‐early Eocene, palynological assemblages and stable carbon isotopes from the Lakadong sandstone member of the East Khasi Hills of Meghalaya (India). The Palaeocene‐Eocene transition (PET) is marked by stratigraphic markers of dinoflagellate cysts (taxa of <jats:italic>Apectodinium augustum</jats:italic>, now <jats:italic>Axiodinium augustum</jats:italic>) and negative carbon isotope excursion. The palynofloral assemblage indicates the sequence represents warm, humid tropical to subtropical conditions with heavy rainfall. The depositional environment of the Lakadong Sandstone Member is interpreted to be neritic. The new insights of this study in this section suggest the PET with the occurrence of <jats:italic>Apectodinium</jats:italic> acme consisting of <jats:italic>A. augustum</jats:italic> at CS5‐15a.","PeriodicalId":22260,"journal":{"name":"Terra Nova","volume":"32 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141150097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Terra NovaPub Date : 2024-05-18DOI: 10.1111/ter.12723
Marcello de Togni, Gianni Balestro, Daniela Rubatto, Daniele Castelli, Marco Gattiglio, Andrea Festa
{"title":"Late Jurassic magmatism in the Ligurian‐Piedmont Ocean constrained by zircon ages of mafic and felsic meta‐intrusives","authors":"Marcello de Togni, Gianni Balestro, Daniela Rubatto, Daniele Castelli, Marco Gattiglio, Andrea Festa","doi":"10.1111/ter.12723","DOIUrl":"https://doi.org/10.1111/ter.12723","url":null,"abstract":"Paleogeographic reconstructions show that the Ligurian‐Piedmont Ocean (LPO) was a relatively narrow oceanic basin but the actual amount of oceanic lithosphere generated and the timing of magmatic accretion are still subjects of debate. New U–Pb dating of zircon from two pairs of FeTi‐oxide metagabbro and metaplagiogranite s.l. of the Susa and Lanzo Valleys Ophiolites (Western Alps) yields Late Jurassic magmatic ages (~150 Ma), 10–15 Ma younger than most of the magmatism in the LPO. The potential significance of the geochronological data presented are discussed in relation to the structural architecture of the LPO, emphasizing that the investigated ophiolites represent the youngest oceanic lithosphere accreted in the Western Alps.","PeriodicalId":22260,"journal":{"name":"Terra Nova","volume":"54 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141058972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Terra NovaPub Date : 2024-05-18DOI: 10.1111/ter.12720
Xiaochun Wei, Hanlin Chen, Eduardo Garzanti, A. Alexander G. Webb, N. Ryan McKenzie, Ping Wang
{"title":"Limitations of provenance diagnoses and maximum‐depositional‐age constraints based on detrital‐zircon geochronology: the fertility bias","authors":"Xiaochun Wei, Hanlin Chen, Eduardo Garzanti, A. Alexander G. Webb, N. Ryan McKenzie, Ping Wang","doi":"10.1111/ter.12720","DOIUrl":"https://doi.org/10.1111/ter.12720","url":null,"abstract":"Detrital zircon U–Pb geochronology (DZG) is widely used in the provenance analysis and calculating maximum depositional ages (MDAs) of strata. To assess the geologic limitations of this approach, we conducted DZG coupled with bulk‐petrology and heavy‐mineral analyses of Miocene volcaniclastic and non‐volcanic siliciclastic sandstones from the SW Tarim Basin. Although these two sandstone types display greatly different bulk‐petrography and heavy‐mineral signatures, they exhibit similar detrital‐zircon‐age spectra, and thus represent a less common case in which interpretations based on DZG alone may misalign with bulk‐sediment provenance. Most zircon‐based MDAs of volcaniclastic sandstones range from 12.3 to 14.8 Ma, deviating from their ca. 11 Ma true depositional age constrained previously. The similarity of zircon‐age spectra in volcaniclastic and siliciclastic sandstones and the 1–4 M.y. the error of the zircon‐based MDAs is ascribed to the low zircon fertility of coeval alkaline magmatic sources. This study emphasizes the importance of an integrated approach to provenance analysis and chronostratigraphy.","PeriodicalId":22260,"journal":{"name":"Terra Nova","volume":"253 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141058985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Terra NovaPub Date : 2024-05-08DOI: 10.1111/ter.12719
Yogaraj Banerjee, Prosenjit Ghosh
{"title":"Freshwater plume‐like condition near the north‐eastern coastal Arabian Sea during early Miocene: Evidence from the stable isotope record in the growth bands of gastropods (Turritella sp.)","authors":"Yogaraj Banerjee, Prosenjit Ghosh","doi":"10.1111/ter.12719","DOIUrl":"https://doi.org/10.1111/ter.12719","url":null,"abstract":"The Early Miocene witnessed major tectonic, palaeoceanographic and climatological reorganizations over the Asian realm. The Himalayan and Tibetan plateau upliftment influenced monsoon intensity during this age. Contemporary high‐resolution tropical hydroclimate records are limited. Here, we present an early Miocene sub‐annual stable isotope record from the growth bands of well‐preserved <jats:italic>Turritella</jats:italic> sp. from the Kachchh basin, Western India. It showed δ<jats:sup>13</jats:sup>C and δ<jats:sup>18</jats:sup>O variabilities from −4.83‰ to −1.80‰ and − 7.06‰ to −2.66‰ (in VPDB) respectively. Conventional oxygen isotope thermometry showed an apparent temperature seasonality from 9.3° to 28.1°C. A comparison of the present early Miocene δ<jats:sup>18</jats:sup>O record with the modern δ<jats:sup>18</jats:sup>O records in the carbonates from coastal‐estuarine environments of the Indian Ocean confirmed a high freshwater influx into the NE Arabian Sea during the early Miocene, similar to the modern‐day freshwater plume events observed in the coastal region.","PeriodicalId":22260,"journal":{"name":"Terra Nova","volume":"126 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140928563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Terra NovaPub Date : 2024-05-02DOI: 10.1111/ter.12718
Marco Mercuri, Stefano Tavani, Simone Fabbi, Giovanni Lavosi, Eugenio Carminati
{"title":"Long live the fault! Double inversion of a Mesozoic rift‐related fault system in the central Apennines","authors":"Marco Mercuri, Stefano Tavani, Simone Fabbi, Giovanni Lavosi, Eugenio Carminati","doi":"10.1111/ter.12718","DOIUrl":"https://doi.org/10.1111/ter.12718","url":null,"abstract":"The San Potito area in central Apennines (Italy), enclosed within the Latium‐Abruzzi carbonate platform, exposes anomalously pelagic carbonates filling an intraplatform basin formed during Jurassic rifting. Oriented obliquely to the regional NW‐SE trend of Cenozoic thrusts and extensional faults, the basin's eastern boundary fault system, striking N‐S, played a pivotal role in structuring orogenic and post‐orogenic features. Large tracts of the fault experienced double reactivation: positive inversion during Miocene shortening, and negative during post‐orogenic extension. Double reactivation is evidenced by older‐on‐younger extensional contacts, and by the change in orientation of thrusts and recent extensional faults from NW‐SE to NNW‐SSE, the latter being consistent with the trend of Jurassic rift‐related structures of the area. This structural interplay highlights the importance of Jurassic faults and their ability in forcing the structural trends, by surviving across multiple deformation stages, even controlling active extensional seismicity.","PeriodicalId":22260,"journal":{"name":"Terra Nova","volume":"88 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140838218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Terra NovaPub Date : 2024-04-13DOI: 10.1111/ter.12715
Riccardo Vassallo, Joseph Martinod, Sandrine Roy, Christian Sue, Laurent Astrade
{"title":"Along‐strike variation of fault slip rate of a transform plate boundary in Tierra del Fuego (South Patagonia)","authors":"Riccardo Vassallo, Joseph Martinod, Sandrine Roy, Christian Sue, Laurent Astrade","doi":"10.1111/ter.12715","DOIUrl":"https://doi.org/10.1111/ter.12715","url":null,"abstract":"The Magallanes–Fagnano Fault is an active strike‐slip structure accommodating the relative displacement between South America and the Scotia Plate. The Chilean portion of the fault is poorly studied because most of it runs below the sea level in the Strait of Magellan. Our tectonic geomorphological study is focused on a rare onshore fault section, along which streams horizontally deflected by hundreds of metres since the last main deglaciation are compatible with a dominant left‐lateral fault kinematics and yield a slip rate of 15.7 ± 2.4 mm/year. This rate is between 2 and 3 times higher than the one estimated on the Argentinian portion of the fault over the same period. This spatial variation may be due to both glacial unloading on the fault zone and/or structural factors. These results point out the need to study strike‐slip faults on several portions to unravel behaviour changes related to internal or external forcing.","PeriodicalId":22260,"journal":{"name":"Terra Nova","volume":"20 1","pages":""},"PeriodicalIF":2.4,"publicationDate":"2024-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140576048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}