A. Testa, A. Valentini, P. Boncio, B. Pace, F. Visini, F. Mirabella, C. Pauselli
{"title":"Probabilistic fault displacement hazard analysis of the Anghiari - Città di Castello normal fault (Italy)","authors":"A. Testa, A. Valentini, P. Boncio, B. Pace, F. Visini, F. Mirabella, C. Pauselli","doi":"10.3301/ijg.2021.07","DOIUrl":"https://doi.org/10.3301/ijg.2021.07","url":null,"abstract":"","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43145014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Mancini, Maria Chiara Caciolli, I. Gaudiosi, Giorgio Andrea Alleanza, G. Cavuoto, M. Coltella, G. Cosentino, V. Di Fiore, A. d'Onofrio, Francesco Gargiulo, G. Milana, A. Pietrosante, P. Pompa, F. Silvestri, M. Vassallo
On August 21, 2017, the volcanic island of Ischia was struck by a Mw 3.9 (http://cnt.rm.ingv.it/event/16796811) earthquake which caused two victims and heavy damages on wide portions of the Casamicciola Terme, Lacco Ameno and Forio municipalities. Following the Decree 1/2018 of the Government Commission for the reconstruction of damaged areas of Ischia Island, a Grade 3 Seismic Microzonation study was committed by each municipality to private consultants, who were scientifically supported by a multidisciplinary team of geologists, geophysicists and geotechnical engineers from CNR, INGV and University of Naples “Federico II”. The existing data from previous geological and geotechnical investigations were integrated with the results of new geo-lithological surveys and geophysical measurements (HVSR, MASW, Down hole tests) carried out by the consultants. The whole amount of data was quality checked, homogenized and collected in a SQLite/SpatiaLite geodatabase using a QGIS open source software by the support team. A geo-lithological map of northern and western sides of the island was then produced, and the results of routine geophysical tests were coupled with those of seismic 2D ambient vibration arrays, to obtain shear wave velocity profiles (several hundreds of meters deep) down to the seismic bedrock, made of lithic tuffs and lavas, and to define its buried morphology. This in turn enabled to draw a map of seismically homogeneous microzones of the entire study area. Cyclic torsional shear tests were carried out on 10 undisturbed soil samples, mainly taken from epiclastic cover deposits, to characterize their non-linear behavior to be adopted for seismic response analyses. These latter were carried out along 1D profiles characterizing each microzone and along selected 2D cross sections running from the Mount Epomeo to the coast. The dynamic analyses allowed to detect and map areas characterized by variable amplification factors, of spectral accelerations throughout different ranges of periods (0.1-0.5s, 04.-0.8s, 0.7-1.1 s). The zones most prone to site amplification are those corresponding to localized graben-like depressions at the toe of Mount Epomeo, such as Maio neighborhood of Casamicciola, where thickened epiclastic covers are entrenched into blocks of uplifted bedrock and where a combination of 1D stratigraphic amplification and 2D reflection and diffraction effects is expected.
{"title":"Seismic microzonation in a complex volcano-tectonic setting: the case of northern and western Ischia Island (southern Italy)","authors":"M. Mancini, Maria Chiara Caciolli, I. Gaudiosi, Giorgio Andrea Alleanza, G. Cavuoto, M. Coltella, G. Cosentino, V. Di Fiore, A. d'Onofrio, Francesco Gargiulo, G. Milana, A. Pietrosante, P. Pompa, F. Silvestri, M. Vassallo","doi":"10.3301/ijg.2021.10","DOIUrl":"https://doi.org/10.3301/ijg.2021.10","url":null,"abstract":"On August 21, 2017, the volcanic island of Ischia was struck by a Mw 3.9 (http://cnt.rm.ingv.it/event/16796811) earthquake which caused two victims and heavy damages on wide portions of the Casamicciola Terme, Lacco Ameno and Forio municipalities. Following the Decree 1/2018 of the Government Commission for the reconstruction of damaged areas of Ischia Island, a Grade 3 Seismic Microzonation study was committed by each municipality to private consultants, who were scientifically supported by a multidisciplinary team of geologists, geophysicists and geotechnical engineers from CNR, INGV and University of Naples “Federico II”. The existing data from previous geological and geotechnical investigations were integrated with the results of new geo-lithological surveys and geophysical measurements (HVSR, MASW, Down hole tests) carried out by the consultants. The whole amount of data was quality checked, homogenized and collected in a SQLite/SpatiaLite geodatabase using a QGIS open source software by the support team. A geo-lithological map of northern and western sides of the island was then produced, and the results of routine geophysical tests were coupled with those of seismic 2D ambient vibration arrays, to obtain shear wave velocity profiles (several hundreds of meters deep) down to the seismic bedrock, made of lithic tuffs and lavas, and to define its buried morphology. This in turn enabled to draw a map of seismically homogeneous microzones of the entire study area. Cyclic torsional shear tests were carried out on 10 undisturbed soil samples, mainly taken from epiclastic cover deposits, to characterize their non-linear behavior to be adopted for seismic response analyses. These latter were carried out along 1D profiles characterizing each microzone and along selected 2D cross sections running from the Mount Epomeo to the coast. The dynamic analyses allowed to detect and map areas characterized by variable amplification factors, of spectral accelerations throughout different ranges of periods (0.1-0.5s, 04.-0.8s, 0.7-1.1 s). The zones most prone to site amplification are those corresponding to localized graben-like depressions at the toe of Mount Epomeo, such as Maio neighborhood of Casamicciola, where thickened epiclastic covers are entrenched into blocks of uplifted bedrock and where a combination of 1D stratigraphic amplification and 2D reflection and diffraction effects is expected.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43114091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Famá, E. Zuccolo, F. Bozzoni, C. Lai, L. Martelli
{"title":"An inter-disciplinary/multi-step approach in defining the input motion for the seismic analysis of masonry buildings struck by the May 29, 2012 M6.0 Emilia earthquake in Northern Italy","authors":"A. Famá, E. Zuccolo, F. Bozzoni, C. Lai, L. Martelli","doi":"10.3301/ijg.2021.08","DOIUrl":"https://doi.org/10.3301/ijg.2021.08","url":null,"abstract":"","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43261806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Late Pleistocene has been characterised by frequent and intense climatic oscillation, well recorded in the Caverna Generosa cave deposits. In this work, micromorphological analyses have been performed on samples from the cave where the stratigraphy is particularly well exposed and complete, in order to obtain temporal and spatial information on climate- and human-related processes during MIS3 and 4. The older layers (more than 50 ka BP - Before Present - old) record a very cold time interval, where ice did not melt during the warmer season, and with little or no vegetation outside the cave. During this cold stage, probably, humans spent a short period in the cave, using bones to light the fire and, later, cave bears dug their hibernation beds in the innermost room. Subsequently (between 50 ka BP and 40 ka BP) a relatively brief climatic amelioration should have occurred, leading to the onset of ice melting during the summer season. Between 40 ka BP and 30 ka BP, loess deposited in the cave entrance, indicating cold and arid conditions in the area. After loess deposition, recovered wet conditions have re-established with freeze and thawing processes influencing the sediments.
晚更新世的特征是频繁而强烈的气候振荡,在Caverna Generosa洞穴沉积物中有很好的记录。在这项工作中,对洞穴中的样品进行了微观形态分析,在那里地层暴露得特别好和完整,以获得关于MIS3和4期间气候和人类相关过程的时间和空间信息。较老的地层(超过50 ka BP-现在之前-古老)记录了一个非常寒冷的时间间隔,在温暖的季节,冰没有融化,洞穴外几乎没有植被。在这个寒冷的阶段,人类可能在洞穴里呆了很短一段时间,用骨头生火,后来,洞穴熊在最里面的房间里挖了冬眠床。随后(在50 ka BP和40 ka BP之间),本应出现相对短暂的气候改善,导致夏季冰开始融化。在40 ka BP和30 ka BP之间,黄土沉积在洞穴入口处,表明该地区的寒冷和干旱条件。黄土沉积后,随着冻融过程对沉积物的影响,恢复的湿润条件重新建立。
{"title":"Frost action and human occupation during the Late Pleistocene in the Italian Southern Alps: micromorphological evidences from the Caverna Generosa cave","authors":"Eleonora Sessa, F. Bona, L. Angiolini","doi":"10.3301/ijg.2020.28","DOIUrl":"https://doi.org/10.3301/ijg.2020.28","url":null,"abstract":"The Late Pleistocene has been characterised by frequent and intense climatic oscillation, well recorded in the Caverna Generosa cave deposits. In this work, micromorphological analyses have been performed on samples from the cave where the stratigraphy is particularly well exposed and complete, in order to obtain temporal and spatial information on climate- and human-related processes during MIS3 and 4. The older layers (more than 50 ka BP - Before Present - old) record a very cold time interval, where ice did not melt during the warmer season, and with little or no vegetation outside the cave. During this cold stage, probably, humans spent a short period in the cave, using bones to light the fire and, later, cave bears dug their hibernation beds in the innermost room. Subsequently (between 50 ka BP and 40 ka BP) a relatively brief climatic amelioration should have occurred, leading to the onset of ice melting during the summer season. Between 40 ka BP and 30 ka BP, loess deposited in the cave entrance, indicating cold and arid conditions in the area. After loess deposition, recovered wet conditions have re-established with freeze and thawing processes influencing the sediments.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41582975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Since Roman age, people living on both sides of the Alps had been seeking different ‘north-west passages’, first overriding the mountains and then moving under them. The first idea of a tunnel under the Mont Blanc was envisaged by de Saussure in 1787. In the 19th century a growing railway network played a fundamental role for the Industrial Revolution, but was hampered for the southern countries by the barrier of the Alps, so that modern transalpine railways became essential for the Reign of Sardinia. This paper presents an historical review of first suggestions, projects, field survey, failed attempts and successful drilling works across the Alps, from the Frejus (1871), San Gottardo (1882) and Simplon (1906) railway tunnels to the Grand St Bernard (1964) and Mont Blanc (1965) highway tunnels, relived within the advances of regional geology and mapping. The Frejus tunnel was conceived by Medal, projected by Maus between Modane and Bardoneche and approved by a ministerial commission, but it was abandoned due to the insurrection of 1848. Later, it was taken up again, developed by Sommeiller, promoted by Cavour himself, and approved in 1857. Technical management was assigned to Sommeiller, Grattoni and Grandis. Frejus was the first, longest and innovating railway tunnel in the world: drilling began in 1857 and ended in December 1870, thanks to a new drilling machine powered by compressed-air. Its inauguration took place on September 1871. When the Frejus drilling was still in progress, John Fell built a mountain railway between Piedmont and Savoy, through the Mont Cenis, following the Napoleonic road. During its four years of work (1868- 1871) it managed to transport about 100,000 travellers, but it was forced to close down when the Frejus railway tunnel was opened. The geological advances and mapping in the Western Alps by the mid-19th century provided information and reliable tools for better planning of great engineering works, but tunnel designs were not always based on a geological survey: the main exceptions were represented by GiorDano (Gottardo, 1881) and Baretti (Mont Blanc, 1880). The former tunnel was drilled, the latter was not accomplished, as other projects were instead preferred across the Western Alps, Colle di Tenda (1898) and then Simplon (1906). After new hopes, the geological study on four project tunnels under the Mont Blanc by Franchi, Kilian and Jacob (Franchi et alii, 1908), and further disappointments, decisive moves to achieve the underground connection between Courmayeur and Chamonix were made by Dino Lora Totino who requested a project to Vittorio Zignoli. Meanwhile, a geological survey for radioactive minerals was promoted by CNRN on the Italian side of the Mont Blanc: field work was performed by Baggio and his staff, and their best result was the discovery of mylonitic-cataclastic shear zones crossing the tunnel route. Their work continued during the drilling inside the Italian part of the Mont Blanc motorway tunnel, s
自罗马时代以来,生活在阿尔卑斯山两侧的人们一直在寻找不同的“西北通道”,先是越过山脉,然后在山脉下移动。1787年,德索绪尔提出了在勃朗峰下修建隧道的第一个想法。19世纪,不断发展的铁路网在工业革命中发挥了重要作用,但阿尔卑斯山的屏障阻碍了南部国家的发展,因此现代跨阿尔卑斯铁路对撒丁岛的统治至关重要。本文对阿尔卑斯山上的第一批建议、项目、实地调查、失败的尝试和成功的钻探工程进行了历史回顾,从Frejus(1871年)、San Gottardo(1882年)和Simplon(1906年)铁路隧道到Grand St Bernard(1964年)和Mont Blanc(1965年)公路隧道,在区域地质和测绘的进步中重温。Frejus隧道由Medal设计,Maus在Modane和Bardoneche之间进行了规划,并得到了部长委员会的批准,但由于1848年的暴动而被放弃。后来,它再次被采用,由Sommeiller开发,Cavour本人推动,并于1857年获得批准。技术管理被分配给Sommeiller、Grattoni和Grandis。Frejus是世界上第一条、最长、创新的铁路隧道:钻探始于1857年,结束于1870年12月,这要归功于一台由压缩空气驱动的新型钻机。它的落成典礼于1871年9月举行。当Frejus钻探仍在进行时,John Fell在皮埃蒙特和萨沃伊之间修建了一条山区铁路,沿着拿破仑的道路穿过Cenis山。在其四年的工作中(1868年至1871年),它成功地运送了大约10万名游客,但当弗雷尤斯铁路隧道开通时,它被迫关闭。19世纪中期,西阿尔卑斯山的地质进步和测绘为更好地规划大型工程提供了信息和可靠的工具,但隧道设计并不总是基于地质调查:主要的例外是GiorDano(Gottardo,1881)和Baretti(Mont Blanc,1880)。前一条隧道被钻探,后一条隧道没有完成,因为其他项目更倾向于穿越西阿尔卑斯山、Colle di Tenda(1898年)和Simplon(1906年)。在新的希望、Franchi、Kilian和Jacob对勃朗峰下四个项目隧道的地质研究(Franchi et alii,1908),以及进一步的失望之后,Dino Lora Totino采取了决定性的行动,以实现Courmayeur和Chamonix之间的地下连接,他向Vittorio Zignoli请求了一个项目。与此同时,CNRN在勃朗峰意大利一侧推动了一项放射性矿物的地质调查:巴乔和他的工作人员进行了实地调查,他们的最佳结果是发现了穿越隧道路线的糜棱岩碎裂剪切带。他们的工作在1959年开始至1962年结束的勃朗峰高速公路隧道意大利部分的钻探过程中继续进行:Mezzacasa在挖掘过程中获得了系统的地质、结构和应用数据,Baggio、Elter和Malaroda对其进行了研究,而法国一侧则由Gudefin进行了调查,Vittel等人在挖掘结束后对其进行研究。这篇论文旨在向所有科学家和技术人员致敬,感谢他们通过地质研究、地图和剖面,使深山变得更透明,从而使穿越它们变得更容易、更安全。地质与隧道工程有着密切的相互作用和互利共赢。预防性地质可以优化技术设计,降低成本,最大限度地减少痛苦的意外。相反,深隧道开挖过程中的系统测量为地学的发展提供了创新的数据。
{"title":"150 years of plans, geological survey and drilling for the Fréjus to Mont Blanc tunnels across the Alpine chain: an historical review","authors":"G. D. Piaz, A. Argentieri","doi":"10.3301/ijg.2020.29","DOIUrl":"https://doi.org/10.3301/ijg.2020.29","url":null,"abstract":"Since Roman age, people living on both sides of the Alps had been seeking different ‘north-west passages’, first overriding the mountains and then moving under them. The first idea of a tunnel under the Mont Blanc was envisaged by de Saussure in 1787. In the 19th century a growing railway network played a fundamental role for the Industrial Revolution, but was hampered for the southern countries by the barrier of the Alps, so that modern transalpine railways became essential for the Reign of Sardinia. This paper presents an historical review of first suggestions, projects, field survey, failed attempts and successful drilling works across the Alps, from the Frejus (1871), San Gottardo (1882) and Simplon (1906) railway tunnels to the Grand St Bernard (1964) and Mont Blanc (1965) highway tunnels, relived within the advances of regional geology and mapping. The Frejus tunnel was conceived by Medal, projected by Maus between Modane and Bardoneche and approved by a ministerial commission, but it was abandoned due to the insurrection of 1848. Later, it was taken up again, developed by Sommeiller, promoted by Cavour himself, and approved in 1857. Technical management was assigned to Sommeiller, Grattoni and Grandis. Frejus was the first, longest and innovating railway tunnel in the world: drilling began in 1857 and ended in December 1870, thanks to a new drilling machine powered by compressed-air. Its inauguration took place on September 1871. When the Frejus drilling was still in progress, John Fell built a mountain railway between Piedmont and Savoy, through the Mont Cenis, following the Napoleonic road. During its four years of work (1868- 1871) it managed to transport about 100,000 travellers, but it was forced to close down when the Frejus railway tunnel was opened. The geological advances and mapping in the Western Alps by the mid-19th century provided information and reliable tools for better planning of great engineering works, but tunnel designs were not always based on a geological survey: the main exceptions were represented by GiorDano (Gottardo, 1881) and Baretti (Mont Blanc, 1880). The former tunnel was drilled, the latter was not accomplished, as other projects were instead preferred across the Western Alps, Colle di Tenda (1898) and then Simplon (1906). After new hopes, the geological study on four project tunnels under the Mont Blanc by Franchi, Kilian and Jacob (Franchi et alii, 1908), and further disappointments, decisive moves to achieve the underground connection between Courmayeur and Chamonix were made by Dino Lora Totino who requested a project to Vittorio Zignoli. Meanwhile, a geological survey for radioactive minerals was promoted by CNRN on the Italian side of the Mont Blanc: field work was performed by Baggio and his staff, and their best result was the discovery of mylonitic-cataclastic shear zones crossing the tunnel route. Their work continued during the drilling inside the Italian part of the Mont Blanc motorway tunnel, s","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47200127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Cantisani, F. Fratini, S. Vettori, E. Pecchioni, L. Chelazzi, A. Arrighetti
The coastal sight towers and the defensive fortresses were in the past distinctive elements of the coastal landscape. They were distributed in particular along the northern coast of the Mediterranean and were built for sighting purposes from the XVIth century against the raids of barbarian pirates who had their bases in the Maghreb coast.A mineralogical and petrographic characterization of the stone materials and mortars of two coastal towers (i.e. Capodomo and Calamoresca) in ruins of Monte Argentario is shown in the present paper. It was found that local lithotypes (e.g. Calcare Cavernoso, calcitic grey marble, dark grey dolostones) were used as building stones and for production of mortars. A detailed study on mortars was conducted by means of high quality polycrystalline X-ray diffraction, optical and electron microscopy. The analysis reveals the presence of Ca and Mg lime-based mortars in the ruins of Capodomo tower, whereas only Ca lime-based mortars were identified in Calamoresca tower.Reaching the towers walking along the paths allows us to know a good part of the lithologies present in the promontory due to the emerging sites in the local morphology; emersion was produced, both because particular lithologies are resistant to the erosion and also because of particular structural or tectonic elements.
{"title":"Mineralogical and petrographic study of building materials from the Argentario coastal towers (Tuscan, Italy): anthropic evidence of the ancient landscape","authors":"E. Cantisani, F. Fratini, S. Vettori, E. Pecchioni, L. Chelazzi, A. Arrighetti","doi":"10.3301/ijg.2020.27","DOIUrl":"https://doi.org/10.3301/ijg.2020.27","url":null,"abstract":"The coastal sight towers and the defensive fortresses were in the past distinctive elements of the coastal landscape. They were distributed in particular along the northern coast of the Mediterranean and were built for sighting purposes from the XVIth century against the raids of barbarian pirates who had their bases in the Maghreb coast.A mineralogical and petrographic characterization of the stone materials and mortars of two coastal towers (i.e. Capodomo and Calamoresca) in ruins of Monte Argentario is shown in the present paper. It was found that local lithotypes (e.g. Calcare Cavernoso, calcitic grey marble, dark grey dolostones) were used as building stones and for production of mortars. A detailed study on mortars was conducted by means of high quality polycrystalline X-ray diffraction, optical and electron microscopy. The analysis reveals the presence of Ca and Mg lime-based mortars in the ruins of Capodomo tower, whereas only Ca lime-based mortars were identified in Calamoresca tower.Reaching the towers walking along the paths allows us to know a good part of the lithologies present in the promontory due to the emerging sites in the local morphology; emersion was produced, both because particular lithologies are resistant to the erosion and also because of particular structural or tectonic elements.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46362588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Brozzetti, Francesca Cerritelli, D. Cirillo, S. Agostini, G. Lavecchia
In the upper Tertiary succession of the Maiella Tectonic Unit (Abruzzo, Italy), coarse calciclastic layers, hereinafter referred to as Roccacaramanico Conglomerate (RCC), were deposited during a short time span which approximates the Miocene-Pliocene boundary. The biostratigraphic characterization of RCC is well constrained by previous studies of foraminifer and nannofossil assemblages. In fact the pelitic interbeds of the RCC are attributed to the Sphaeroidinellopsis spp. Biozone and to the MNN12 Nannofossil Zone belonging to the earliest Pliocene.Previous works referred this conglomerate to Apennine- fed sediment gravity-flows however, in the absence of detailed compositional data and of a regional-scale sedimentological study of the layers, only generic hypotheses on the source-area and on the nature of the event which triggered the RCC deposition, were formulated.Here we present the results of an original investigation on the RCC cropping out within the Maiella Tectonic Unit, in the area delimited westward by the Morrone-Porrara thrust and, towards south-east, by the Molise allochthonous Units.In this area, a fairly continuous RCC horizon, exposed on both limbs of the Maiella anticline, was mapped and logged in detail. Our lithostratigraphic analysis allowed to make hypotheses on depositional mechanisms of RCC and revealed that it consists of several (six to ten) major depositional events producing locally amalgamated pluri- metric clastic layers.Our facies analysis highlighted that previous studies had generally underestimated the overall thickness of the layers and that in the southernmost examined outcrops (Palena, Taranta Peligna and Lama dei Peligni), the RCC is characterized by higher thickness, coarser grain-size, poorer sorting and more pronounced channeling compared to that cropping out in northernmost areas (Roccacaramanico, San Nicolao and San Valentino). The recognition of facies-types characterized by greater proximality in the southern Maiella area, and the overall geometric reconstruction of the depositional architecture of the RCC horizon, suggests that, contrary to what was previously assumed, the major sediment gravity-flows were fed from the south-eastern edge of the basin. This result is also confirmed by the paleocurrent data, testifying northward flowing currents directed SSE-NNW.The compositional analysis of RCC, highlighted an almost totally calcareous composition of the clasts and a poor and scattered siliciclastic fraction, mainly occurring as fine grained matrix. Clasts showing inner platform, bio-constructed margin, ramp, transitional and basinal facies, of different ages, are mixed throughout the layers. Nevertheless, these data allowed us to make inferences on the provenance of the sediment supply and on the stratigraphic successions that were undergoing erosion in the area surrounding the basin, around the Messinian-Pliocene boundary.A quantitative assessment of the RCC volume was finally achieved, taking into a
在意大利阿布鲁佐地区Maiella构造单元的上第三系演替中,在较短的时间跨度内沉积了粗糙的砾屑层,以下简称Roccacaramanico砾岩(RCC),沉积时间接近中新世-上新世界线。RCC的生物地层特征受到有孔虫和纳米化石组合研究的限制。事实上,RCC的泥质互层属于Sphaeroidinellopsis spp.生物带和属于上新世早期的MNN12纳米化石带。先前的研究将这种砾岩与亚平宁盆地沉积重力流联系起来,然而,由于缺乏详细的成分数据和区域尺度的沉积学研究,只有关于源区和引发RCC沉积的事件性质的一般假设被制定出来。在这里,我们介绍了对Maiella构造单元内的碾压砾岩的原始调查结果,该构造单元位于向西由Morrone-Porrara逆冲构造单元划分,向东南由Molise异质单元划分的区域。在这个地区,一个相当连续的RCC层位,暴露在Maiella背斜的两侧,被详细地绘制和记录。我们的岩石地层分析允许对RCC的沉积机制做出假设,并揭示了它由几个(6到10个)主要沉积事件组成,产生了局部合并的多粒碎屑层。我们的相分析强调,以往的研究普遍低估了层的整体厚度,并且在最南端(Palena, Taranta Peligna和Lama dei Peligni)检查的露头中,RCC的特征是厚度更高,粒度更粗,分选更差,与最北部地区(Roccacaramanico, San Nicolao和San Valentino)相比,通道更明显。对Maiella南部地区近缘性较大的相类型的识别,以及RCC层位沉积构型的整体几何重建表明,与之前的假设相反,主要的沉积物重力流来自盆地的东南边缘。古海流资料也证实了这一结果,证明北流方向为SSE-NNW。RCC的成分分析表明,碎屑几乎完全为钙质组成,而硅塑性组分则较为分散,主要以细粒基质形式存在。不同时代的内台地相、生物构造边缘相、斜坡相、过渡相和盆地相碎屑在各层间混杂。尽管如此,这些数据使我们能够推断沉积物供应的来源,以及在盆地周围地区,在迈西尼亚-上新世边界附近,正在经历侵蚀的地层序列。考虑到我们在现场测量的厚度值或其他从深测井中获得的厚度值,最终实现了RCC体积的定量评估,并将这些厚度应用于一组穿越Maiella背斜的恢复地质剖面。我们的计算提供了约700平方公里的最小面积和约7平方公里的保守体积估计,这允许有效地适用于碾压混凝土,即“巨型床”的定义。这突出了其作为Abruzzi演替最东端区域标志层的重要性,其明确的地层位置(跨越中新世/上新世年代地层界线)更加强调了这一重要性。
{"title":"The Roccacaramanico Conglomerate (Maiella Tectonic Unit) in the frame of the Abruzzo early Pliocene Foreland Basin System: stratigraphic and structural implications","authors":"F. Brozzetti, Francesca Cerritelli, D. Cirillo, S. Agostini, G. Lavecchia","doi":"10.3301/ijg.2020.04","DOIUrl":"https://doi.org/10.3301/ijg.2020.04","url":null,"abstract":"In the upper Tertiary succession of the Maiella Tectonic Unit (Abruzzo, Italy), coarse calciclastic layers, hereinafter referred to as Roccacaramanico Conglomerate (RCC), were deposited during a short time span which approximates the Miocene-Pliocene boundary. The biostratigraphic characterization of RCC is well constrained by previous studies of foraminifer and nannofossil assemblages. In fact the pelitic interbeds of the RCC are attributed to the Sphaeroidinellopsis spp. Biozone and to the MNN12 Nannofossil Zone belonging to the earliest Pliocene.Previous works referred this conglomerate to Apennine- fed sediment gravity-flows however, in the absence of detailed compositional data and of a regional-scale sedimentological study of the layers, only generic hypotheses on the source-area and on the nature of the event which triggered the RCC deposition, were formulated.Here we present the results of an original investigation on the RCC cropping out within the Maiella Tectonic Unit, in the area delimited westward by the Morrone-Porrara thrust and, towards south-east, by the Molise allochthonous Units.In this area, a fairly continuous RCC horizon, exposed on both limbs of the Maiella anticline, was mapped and logged in detail. Our lithostratigraphic analysis allowed to make hypotheses on depositional mechanisms of RCC and revealed that it consists of several (six to ten) major depositional events producing locally amalgamated pluri- metric clastic layers.Our facies analysis highlighted that previous studies had generally underestimated the overall thickness of the layers and that in the southernmost examined outcrops (Palena, Taranta Peligna and Lama dei Peligni), the RCC is characterized by higher thickness, coarser grain-size, poorer sorting and more pronounced channeling compared to that cropping out in northernmost areas (Roccacaramanico, San Nicolao and San Valentino). The recognition of facies-types characterized by greater proximality in the southern Maiella area, and the overall geometric reconstruction of the depositional architecture of the RCC horizon, suggests that, contrary to what was previously assumed, the major sediment gravity-flows were fed from the south-eastern edge of the basin. This result is also confirmed by the paleocurrent data, testifying northward flowing currents directed SSE-NNW.The compositional analysis of RCC, highlighted an almost totally calcareous composition of the clasts and a poor and scattered siliciclastic fraction, mainly occurring as fine grained matrix. Clasts showing inner platform, bio-constructed margin, ramp, transitional and basinal facies, of different ages, are mixed throughout the layers. Nevertheless, these data allowed us to make inferences on the provenance of the sediment supply and on the stratigraphic successions that were undergoing erosion in the area surrounding the basin, around the Messinian-Pliocene boundary.A quantitative assessment of the RCC volume was finally achieved, taking into a","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/ijg.2020.04","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69480281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
An outline of the geology of the Italian Northern Apennines, to accompany a geological map at 1:250,000 scale covering the Emilia- Romagna, Marche, Tuscany and Umbria regions, is presented herein. The map is intended as a first result of a longer term project carried out by the Geological Surveys of the above regions, aimed to create a common geological map at 1:10,000 scale, useful for environmental planning and management.The lithostratigraphic units are grouped in domains and successions (with references to main tectonic units), and a special effort was made to correlate similar lithostratigraphic units across the area. The enclosed geological map distinguishes stratigraphic successions deposited in: a) Ligurian Domain (Internal and External Ligurian domains); b) Subligurian Domain; c) Tuscan Domain (Tuscan Succession, Tuscan Metamorphic Succession, Cervarola- Falterona Succession, Modino Succession, Rentella Succession, Pseudoverrucano Succession); Umbria-Marche-Romagna Domain. Tectonic units derived from regional tectonic melanges and shear zones (Sestola-Vidiciatico Unit), and units affected by HP metamorphism in the Tuscan Archipelago and southern Tuscany have been mapped. Distinguished younger successions are: a) Epiligurian Succession; b) Miocene-Pleistocene succession of the Tyrrhenian margin; c) Miocene- Pleistocene succession of the Po Plain and Adriatic margin. The main outcrops of magmatic rocks (Miocene-Pleistocene in age) and Quaternary alluvial, continental and coastal deposits have also been mapped. Main tectonic contacts (high-angle normal faults, main thrust and low-angle normal faults) are indicated. The 1:250,000 geological map of the Northern Apennines is freely available as PDF, raster and vector GIS data from the web site: https://www.geological-map.it.
{"title":"An outline of the geology of the Northern Apennines (Italy), with geological map at 1:250,000 scale","authors":"P. Conti, G. Cornamusini, L. Carmignani","doi":"10.3301/IJG.2019.25","DOIUrl":"https://doi.org/10.3301/IJG.2019.25","url":null,"abstract":"An outline of the geology of the Italian Northern Apennines, to accompany a geological map at 1:250,000 scale covering the Emilia- Romagna, Marche, Tuscany and Umbria regions, is presented herein. The map is intended as a first result of a longer term project carried out by the Geological Surveys of the above regions, aimed to create a common geological map at 1:10,000 scale, useful for environmental planning and management.The lithostratigraphic units are grouped in domains and successions (with references to main tectonic units), and a special effort was made to correlate similar lithostratigraphic units across the area. The enclosed geological map distinguishes stratigraphic successions deposited in: a) Ligurian Domain (Internal and External Ligurian domains); b) Subligurian Domain; c) Tuscan Domain (Tuscan Succession, Tuscan Metamorphic Succession, Cervarola- Falterona Succession, Modino Succession, Rentella Succession, Pseudoverrucano Succession); Umbria-Marche-Romagna Domain. Tectonic units derived from regional tectonic melanges and shear zones (Sestola-Vidiciatico Unit), and units affected by HP metamorphism in the Tuscan Archipelago and southern Tuscany have been mapped. Distinguished younger successions are: a) Epiligurian Succession; b) Miocene-Pleistocene succession of the Tyrrhenian margin; c) Miocene- Pleistocene succession of the Po Plain and Adriatic margin. The main outcrops of magmatic rocks (Miocene-Pleistocene in age) and Quaternary alluvial, continental and coastal deposits have also been mapped. Main tectonic contacts (high-angle normal faults, main thrust and low-angle normal faults) are indicated. The 1:250,000 geological map of the Northern Apennines is freely available as PDF, raster and vector GIS data from the web site: https://www.geological-map.it.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/IJG.2019.25","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46742440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Landforms characterized by high scientific value (i.e. geomorphosites) might undergo modifications due to intrinsic and extrinsic factors (natural and human-induced processes). In the framework of geoheritage analyses, the assessment of the value (scientific or additional) of geomorphosites should be performed side by side with the analysis on the risk of degradation (fragility and vulnerability). A multidisciplinary method is proposed for the analysis of landforms that are potentially fragile but outstanding for their scientific value related to geological, geomorphological and ecological values. A geomorphological map was produced for the glacial plateaux of the Loana Valley (Central-Western Italian Alps), where an outstanding geomorphosite was detected: the Cortenuovo Calcareous Ridge. The site is herein analysed in terms of the representativeness of geological and (paleo)geomorphological features as well as for its support role to the ecosystem. For dissemination purposes, a simplified version of the geomorphological map (i.e., geomorphological box) was prepared for the site. Specific morphometric and dendrogeomorphological analyses were then performed to investigate more in detail the risk of degradation of the site. It resulted to be a spatially restricted hotspot of geodiversity, characterized by an average surface lowering rate (0.44 cm/y on average) comparable to that achieved in similar geomorphologic contexts in the Alpine environment. The obtained results testify to a potential vulnerability to natural processes of this highly scientific valued site, which will surely benefit from a legal recognition as a component of geoheritage, with a specific regulation for its protection, that could prove to be strategic.
{"title":"A multidisciplinary approach for physical landscape analysis: scientific value and risk of degradation of outstanding landforms in the glacial plateau of the Loana Valley (Central-Western Italian Alps)","authors":"I. Bollati, B. C. Lenz, V. Caironi","doi":"10.3301/ijg.2020.01","DOIUrl":"https://doi.org/10.3301/ijg.2020.01","url":null,"abstract":"Landforms characterized by high scientific value (i.e. geomorphosites) might undergo modifications due to intrinsic and extrinsic factors (natural and human-induced processes). In the framework of geoheritage analyses, the assessment of the value (scientific or additional) of geomorphosites should be performed side by side with the analysis on the risk of degradation (fragility and vulnerability). A multidisciplinary method is proposed for the analysis of landforms that are potentially fragile but outstanding for their scientific value related to geological, geomorphological and ecological values. A geomorphological map was produced for the glacial plateaux of the Loana Valley (Central-Western Italian Alps), where an outstanding geomorphosite was detected: the Cortenuovo Calcareous Ridge. The site is herein analysed in terms of the representativeness of geological and (paleo)geomorphological features as well as for its support role to the ecosystem. For dissemination purposes, a simplified version of the geomorphological map (i.e., geomorphological box) was prepared for the site. Specific morphometric and dendrogeomorphological analyses were then performed to investigate more in detail the risk of degradation of the site. It resulted to be a spatially restricted hotspot of geodiversity, characterized by an average surface lowering rate (0.44 cm/y on average) comparable to that achieved in similar geomorphologic contexts in the Alpine environment. The obtained results testify to a potential vulnerability to natural processes of this highly scientific valued site, which will surely benefit from a legal recognition as a component of geoheritage, with a specific regulation for its protection, that could prove to be strategic.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":" ","pages":""},"PeriodicalIF":1.8,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/ijg.2020.01","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45967887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Citton, A. Ronchi, U. Nicosia, Eva Sacchi, S. Maganuco, A. Cipriani, Giulia Innamorati, C. Zuccari, Fabio Manucci, M. Romano
We report here on the first tetrapod tracks from the Triassic of the Nurra region (north-western Sardinia, Italy). The specimens were found on sandstone blocks used to build a fence limiting a seasonal camping, in the coastal area north of Capo Caccia promontory. Lithologic and petrographic features allowed an assignment of the track-bearing blocks to the middle-upper portion of the Anisian (Middle Triassic) Arenarie di Cala Viola (Buntsandstein). Footprints are attributed to the ichnotaxa Rhynchosauroides and Rotodactylus, two common ichnotaxa of late Early Triassic and Middle Triassic ichnofaunas of Europe and United States, commonly referred in the literature to neodiapsid and archosaur producers, respectively.
我们在这里报告了来自Nurra地区(意大利撒丁岛西北部)三叠纪的第一批四足动物足迹。这些标本是在卡波卡西亚角北部沿海地区用来建造季节性露营围栏的砂岩块上发现的。岩性和岩石学特征表明,这些带径迹的块体属于Anisian(中三叠统)Arenarie di Cala Viola (Buntsandstein)的中上段。足迹归属于早三叠世晚期和中三叠世欧美地区常见的两个鱼类群——Rhynchosauroides和Rotodactylus,文献中通常分别将其称为新鲤科动物和祖龙的生产者。
{"title":"Tetrapod tracks from the Middle Triassic of NW Sardinia (Nurra region, Italy)","authors":"P. Citton, A. Ronchi, U. Nicosia, Eva Sacchi, S. Maganuco, A. Cipriani, Giulia Innamorati, C. Zuccari, Fabio Manucci, M. Romano","doi":"10.3301/ijg.2020.07","DOIUrl":"https://doi.org/10.3301/ijg.2020.07","url":null,"abstract":"We report here on the first tetrapod tracks from the Triassic of the Nurra region (north-western Sardinia, Italy). The specimens were found on sandstone blocks used to build a fence limiting a seasonal camping, in the coastal area north of Capo Caccia promontory. Lithologic and petrographic features allowed an assignment of the track-bearing blocks to the middle-upper portion of the Anisian (Middle Triassic) Arenarie di Cala Viola (Buntsandstein). Footprints are attributed to the ichnotaxa Rhynchosauroides and Rotodactylus, two common ichnotaxa of late Early Triassic and Middle Triassic ichnofaunas of Europe and United States, commonly referred in the literature to neodiapsid and archosaur producers, respectively.","PeriodicalId":49317,"journal":{"name":"Italian Journal of Geosciences","volume":"1 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2020-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.3301/ijg.2020.07","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42172771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}