Scientific Drilling最新文献

{"title":"Hipercorig – an innovative hydraulic coring system recovering over 60 m long sediment cores from deep perialpine lakes","authors":"U. Harms, U. Raschke, F. Anselmetti, M. Strasser, V. Wittig, M. Wessels, S. Schaller, S. Fabbri, R. Niederreiter, A. Schwalb","doi":"10.5194/sd-28-29-2020","DOIUrl":"https://doi.org/10.5194/sd-28-29-2020","url":null,"abstract":"Abstract. The record of past environmental conditions and changes archived in lacustrine sediments serves as an important element in paleoenvironmental and climate research. A main barrier in accessing these archives is the undisturbed recovery of long cores from deep lakes. In this study, we have developed and tested a new, environmentally friendly coring tool and modular barge, centered around a down-the-hole hydraulic hammering of an advanced piston coring system, called the Hipercorig. Test beds for the evaluation of the performance of the system were two periglacial lakes, Mondsee and Constance, located on the northern edge of the Alpine chain. These lakes are notoriously difficult to sample beyond ∼ 10 m sediment depths due to dense glacial deposits obstructing deeper coring. Both lakes resemble many global lake systems with hard and coarse layers at depth, so the gained experience using this novel technology can be applied to other lacustrine or even marine basins. These two experimental drilling projects resulted in up to 63 m coring depth and successful coring operations in up to 204 m water depth, providing high-quality, continuous cores with 87 % recovery. Initial core description and scanning of the 63 m long core from Mondsee and two 20 and 24 m long cores from Lake Constance provided novel insights beyond the onset of deglaciation of the northern Alpine foreland dating back to ∼ 18 400 cal BP.\u0000","PeriodicalId":51840,"journal":{"name":"Scientific Drilling","volume":"44 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85829510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new high-temperature borehole fluid sampler: the Multi-Temperature Fluid Sampler","authors":"C. Wheat, C. Kitts, C. Webb, Rachel Stolzman, Ann McGuire, T. Fournier, T. Pettigrew, H. Jannasch","doi":"10.5194/sd-28-43-2020","DOIUrl":"https://doi.org/10.5194/sd-28-43-2020","url":null,"abstract":"Abstract. Deep ( >1  km depth) scientific boreholes are unique assets\u0000that can be used to address a variety of microbiological, hydrologic, and\u0000biogeochemical hypotheses. Few of these deep boreholes exist in oceanic\u0000crust. One of them, Deep Sea Drilling Project Hole 504B, reaches\u0000 ∼190 ∘ C at its base. We designed, fabricated, and\u0000laboratory-tested the Multi-Temperature Fluid Sampler (MTFS), a non-gas-tight, titanium syringe-style fluid sampler for borehole applications\u0000that is tolerant of such high temperatures. Each of the 12 MTFS units\u0000collects a single 1 L sample at a predetermined temperature, which is\u0000defined by the trigger design and a shape memory alloy (SMA). SMAs have the\u0000innate ability to be deformed and only return to their initial shapes when\u0000their activation temperatures are reached, thereby triggering a sampler at a\u0000predetermined temperature. Three SMA-based trigger mechanisms, which do not\u0000rely on electronics, were tested. Triggers were released at temperatures\u0000spanning from 80 to 181  ∘ C. The MTFS was set for\u0000deployment on International Ocean Discovery Program Expedition 385T, but\u0000hole conditions precluded its use. The sampler is ready for use in deep\u0000oceanic or continental scientific boreholes with minimal training for\u0000operational success.","PeriodicalId":51840,"journal":{"name":"Scientific Drilling","volume":"93 1","pages":"43-48"},"PeriodicalIF":1.2,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78660159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Borehole research in New York State can advance utilization of low-enthalpy geothermal energy, management of potential risks, and understanding of deep sedimentary and crystalline geologic systems","authors":"T. Jordan, P. Fulton, J. Tester, D. Bruhn, H. Asanuma, U. Harms, Chaoyi Wang, D. Schmitt, P. Vardon, H. Hofmann, Tom Pasquini, Jared D. Smith","doi":"10.5194/sd-28-75-2020","DOIUrl":"https://doi.org/10.5194/sd-28-75-2020","url":null,"abstract":"Abstract. In January 2020, a scientific borehole planning workshop sponsored by the International Continental Scientific Drilling Program was convened at Cornell University in the northeastern United States. Cornell is planning to drill test wells to evaluate the potential to use geothermal heat from depths in the range of 2700–4500 m and rock temperatures of about 60 to 120  ∘ C to heat its campus buildings. Cornell encourages the Earth\u0000sciences community to envision how these boreholes can also be used to\u0000advance high-priority subsurface research questions. Because nearly all scientific boreholes on the continents are targeted to examine iconic\u0000situations, there are large gaps in understanding of the “average”\u0000intraplate continental crust. Hence, there is uncommon and widely applicable\u0000value to boring and investigating a “boring” location. The workshop\u0000focused on designing projects to investigate the coupled\u0000thermal–chemical–hydrological–mechanical workings of continental crust. Connecting the practical and scientific goals of the boreholes are a set of\u0000currently unanswered questions that have a common root: the complex\u0000relationships among pore pressure, stress, and strain in a heterogeneous and\u0000discontinuous rock mass across conditions spanning from natural to human perturbations and short to long timescales. The need for data and subsurface characterization vital for decision-making around the prospective\u0000Cornell geothermal system provides opportunities for experimentation,\u0000measurement, and sampling that might lead to major advances in the\u0000understanding of hydrogeology, intraplate seismicity, and fluid/chemical\u0000cycling. Subsurface samples could also enable regional geological studies\u0000and geobiology research. Following the workshop, the U.S. Department of\u0000Energy awarded funds for a first exploratory borehole, whose proposed design\u0000and research plan rely extensively on the ICDP workshop recommendations.","PeriodicalId":51840,"journal":{"name":"Scientific Drilling","volume":"18 1","pages":"75-91"},"PeriodicalIF":1.2,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73907123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ICDP workshop on the Lake Tanganyika Scientific Drilling Project: a late Miocene–present record of climate, rifting, and ecosystem evolution from the world's oldest tropical lake","authors":"J. Russell, P. Barker, A. Cohen, S. Ivory, I. Kimirei, C. Lane, M. Leng, N. Maganza, M. McGlue, E. Msaky, A. Noren, L. P. Park Boush, W. Salzburger, C. Scholz, R. Tiedemann, Shaidu Nuru","doi":"10.5194/sd-27-53-2020","DOIUrl":"https://doi.org/10.5194/sd-27-53-2020","url":null,"abstract":"Abstract. The Neogene and Quaternary are characterized by enormous changes in global\u0000climate and environments, including global cooling and the establishment of\u0000northern high-latitude glaciers. These changes reshaped global ecosystems,\u0000including the emergence of tropical dry forests and savannahs that are found\u0000in Africa today, which in turn may have influenced the evolution of humans\u0000and their ancestors. However, despite decades of research we lack long,\u0000continuous, well-resolved records of tropical climate, ecosystem changes,\u0000and surface processes necessary to understand their interactions and\u0000influences on evolutionary processes. Lake Tanganyika, Africa, contains the\u0000most continuous, long continental climate record from the mid-Miocene\u0000(∼10 Ma) to the present anywhere in the tropics and has long\u0000been recognized as a top-priority site for scientific drilling. The lake is\u0000surrounded by the Miombo woodlands, part of the largest dry tropical biome\u0000on Earth. Lake Tanganyika also harbors incredibly diverse endemic biota\u0000and an entirely unexplored deep microbial biosphere, and it provides textbook\u0000examples of rift segmentation, fault behavior, and associated surface\u0000processes. To evaluate the interdisciplinary scientific opportunities that\u0000an ICDP drilling program at Lake Tanganyika could offer, more than 70\u0000scientists representing 12 countries and a variety of scientific\u0000disciplines met in Dar es Salaam, Tanzania, in June 2019. The team\u0000developed key research objectives in basin evolution, source-to-sink\u0000sedimentology, organismal evolution, geomicrobiology, paleoclimatology,\u0000paleolimnology, terrestrial paleoecology, paleoanthropology, and\u0000geochronology to be addressed through scientific drilling on Lake\u0000Tanganyika. They also identified drilling targets and strategies, logistical\u0000challenges, and education and capacity building programs to be carried out\u0000through the project. Participants concluded that a drilling program at Lake\u0000Tanganyika would produce the first continuous Miocene–present record from\u0000the tropics, transforming our understanding of global environmental change,\u0000the environmental context of human origins in Africa, and providing a\u0000detailed window into the dynamics, tempo and mode of biological\u0000diversification and adaptive radiations.\u0000","PeriodicalId":51840,"journal":{"name":"Scientific Drilling","volume":"90 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84552305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-resolution late Holocene sedimentary cores record the long history of the city of Cádiz (south-western Spain)","authors":"F. Salomon, D. Bernal-Casasola, J. J. Díaz, M. Lara, S. Domínguez-Bella, D. Ertlen, P. Wassmer, P. Adam, P. Schaeffer, L. Hardion, C. Vittori, S. Chapkanski, Hugo Delile, L. Schmitt, F. Preusser, M. Trautmann, A. Masi, C. Vignola, L. Sadori, Jacob Morales, P. Vidal Matutano, Vincent Robin, Benjamin Keller, Á. Sanchez Bellón, J. Martínez López, G. Rixhon","doi":"10.5194/sd-27-35-2020","DOIUrl":"https://doi.org/10.5194/sd-27-35-2020","url":null,"abstract":"Abstract. Today, coastal cities worldwide are facing major changes\u0000resulting from climate change and anthropogenic forcing, which requires\u0000adaptation and mitigation strategies to be established. In this context,\u0000sedimentological archives in many Mediterranean cities record a\u0000multi-millennial history of environmental dynamics and human adaptation,\u0000revealing a long-lasting resilience. Founded by the Phoenicians around 3000 years ago, Cádiz (south-western Spain) is a key example of a coastal\u0000resilient city. This urban centre is considered to be one of the first\u0000cities of western Europe and has experienced major natural hazards during its\u0000long history, such as coastal erosion, storms, and also tsunamis (like the\u0000one in 1755 CE following the destructive Lisbon earthquake). In the framework of an international, joint archaeological and\u0000geoarchaeological project, three cores have been drilled in a marine\u0000palaeochannel that ran through the ancient city of Cádiz. These\u0000cores reveal a ≥50 m thick Holocene sedimentary sequence. Importantly,\u0000most of the deposits date from the 1st millennium BCE to the 1st\u0000millennium CE. This exceptional sedimentary archive will allow our\u0000scientific team to achieve its research goals, which are (1) to reconstruct\u0000the palaeogeographical evolution of this specific coastal area; (2) to trace\u0000the intensity of activities of the city of Cádiz based on archaeological\u0000data, as well as geochemical and palaeoecological indicators; and (3) to\u0000identify and date high-energy event deposits such as storms and tsunamis.\u0000","PeriodicalId":51840,"journal":{"name":"Scientific Drilling","volume":"36 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81411363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Late Miocene wood recovered in Bengal–Nicobar submarine fan sediments by IODP Expedition 362","authors":"L. McNeill, B. Dugan, K. Petronotis, K. Milliken, J. Francis","doi":"10.5194/sd-27-49-2020","DOIUrl":"https://doi.org/10.5194/sd-27-49-2020","url":null,"abstract":"Abstract. Drilling and coring during IODP Expedition 362 in the eastern Indian Ocean\u0000encountered probably the largest wood fragment ever recovered in scientific\u0000ocean drilling. The wood is Late Miocene in age and buried beneath\u0000 ∼800  m of siliciclastic mud and sand of the Bengal–Nicobar\u0000Fan. The wood is well preserved. Possible origins include the hinterland to\u0000the north, with sediment transported as part of the submarine fan sedimentary\u0000processes, or the Sunda subduction zone to the east, potentially as a\u0000megathrust tsunami deposit.","PeriodicalId":51840,"journal":{"name":"Scientific Drilling","volume":"103 1","pages":"49-52"},"PeriodicalIF":1.2,"publicationDate":"2020-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73026745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New Chikyu Shallow Core Program (SCORE): exploring mass transport deposits and the subseafloor biosphere off Cape Erimo, northern Japan","authors":"Y. Kubo, F. Inagaki, S. Tonai, G. Uramoto, O. Takano, Yasuhiro Yamada","doi":"10.5194/sd-27-25-2020","DOIUrl":"https://doi.org/10.5194/sd-27-25-2020","url":null,"abstract":"Abstract. The Chikyu Shallow Core Program (SCORE) has been started to provide\u0000more opportunities for the scientific ocean drilling of shallow boreholes\u0000(up to 100 m) during a short-term expedition. The proposal flow is a\u0000simplified version of that of the International Ocean Discovery Program (IODP).\u0000Although there are several limitations for a SCORE project, the opportunity\u0000to retrieve 100 m of continuous core samples will be of great interest for\u0000the scientific ocean drilling community in multiple disciplines. The first\u0000expedition of the SCORE program was implemented off Cape Erimo, Hokkaido,\u0000northern Japan. The target of the drilling was to investigate the impact of\u0000submarine mass transport on the subseafloor sedimentary biosphere. In the\u0000preliminary observation of the core samples, including X-ray computed tomography (CT) scan image\u0000analysis, chaotic and inclined beds were found and interpreted as mass\u0000transport deposit (MTD) units.\u0000","PeriodicalId":51840,"journal":{"name":"Scientific Drilling","volume":"26 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80182986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbial diversity of drilling fluids from 3000 m deep Koyna pilot borehole provides insights into the deep biosphere of continental earth crust","authors":"H. Bose, A. Dutta, Ajoy K. Roy, Abhishek Gupta, S. Mukhopadhyay, B. Mohapatra, Jayeeta Sarkar, Sukanta Roy, S. K. Kazy, Pinaki Sar","doi":"10.5194/sd-27-1-2020","DOIUrl":"https://doi.org/10.5194/sd-27-1-2020","url":null,"abstract":"Abstract. Scientific deep drilling of the Koyna pilot borehole into the continental\u0000crust up to a depth of 3000 m below the surface at the Deccan Traps, India, provided a\u0000unique opportunity to explore microbial life within the deep granitic bedrock of the Archaean Eon. Microbial communities of the returned drilling fluid\u0000(fluid returned to the mud tank from the underground during the drilling\u0000operation; designated here as DF) sampled during the drilling operation of the\u0000Koyna pilot borehole at a depth range of 1681–2908 metres below the surface\u0000(m b.s.) were explored to gain a glimpse of the deep biosphere underneath the\u0000continental crust. Change of pH to alkalinity, reduced abundance of Si and\u0000Al, but enrichment of Fe, Ca and SO 4 2 - in the samples from\u0000deeper horizons suggested a gradual infusion of elements or ions from the\u0000crystalline bedrock, leading to an observed geochemical shift in the DF.\u0000Microbial communities of the DFs from deeper horizons showed progressively\u0000increased abundance of Firmicutes, Gammaproteobacteria and Actinobacteria as bacterial taxa and members of Euryarchaeota as the major\u0000archaeal taxa. Microbial families, well known to strive in strictly\u0000anaerobic and extremophilic environments, (e.g. Thermoanaerobacteraceae, Clostridiaceae, Bacillaceae, Carnobacteriaceae, Ruminococcaceae), increased in the\u0000samples obtained at a depth range of 2000 to 2908 m b.s. Phylogenetic analysis\u0000of common and unique operational taxonomic units (OTUs) of DF samples\u0000indicated signatures of extremophilic and deep subsurface relevant bacterial\u0000genera (Mongoliitalea, Hydrogenophaga, Marinilactibacillus, Anoxybacillus, Symbiobacterium, Geosporobacter, Thermoanaerobacter). Thermophilic, obligatory anaerobic sulfate-reducing\u0000bacterial taxa known to inhabit the deep subsurface were enriched\u0000from DF samples using sulfate as a terminal electron acceptor. This report on\u0000the geomicrobiology of the DF obtained during drilling of the deep\u0000subsurface of the Deccan Traps showed new opportunities to investigate deep\u0000life from terrestrial, granite-rock-hosted habitats.","PeriodicalId":51840,"journal":{"name":"Scientific Drilling","volume":"41 1","pages":"1-23"},"PeriodicalIF":1.2,"publicationDate":"2020-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84754145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scientific drilling workshop on the Weihe Basin Drilling Project (WBDP): Cenozoic tectonic–monsoon interactions","authors":"Z. An, Peizhen Zhang, H. Vogel, Yougui Song, J. Dodson, T. Wiersberg, Xijie Feng, Huayu Lu, L. Ai, Youbin Sun","doi":"10.5194/egusphere-egu2020-12774","DOIUrl":"https://doi.org/10.5194/egusphere-egu2020-12774","url":null,"abstract":"Abstract. The Weihe Basin, enclosed by the Chinese Loess Plateau to the north and the\u0000Qinling Mountains to the south, is an outstanding, world-class continental\u0000site for obtaining high-resolution multi-proxy records that reflect\u0000environmental changes spanning most of the Cenozoic. Previous geophysical\u0000and sedimentary studies indicate that the basin hosts 6000–8000 m thick\u0000fluvial–lacustrine sedimentary successions spanning the Eocene to Holocene. This sedimentary record provides an excellent and unique archive to decipher\u0000long-term tectonic–climate interactions related to the uplift of the Tibetan Plateau, the onset/evolution of the Asian monsoon, and the development of the biogeography of East Asia. Owing to its location at the interface of the opposing westerly and Asian monsoon circulation systems, the Weihe Basin\u0000also holds enormous promise for providing a record of changes in these circulation systems in response to very different boundary conditions since the Eocene. To develop an international scientific drilling programme in the Weihe Basin, the Institute of Earth Environment, Chinese Academy of\u0000Sciences, organized a dedicated workshop with 55 participants from eight countries. The workshop was held in Xi'an, China, from 15 to 18 October 2019. Workshop participants conceived the key scientific objectives of the\u0000envisaged Weihe Basin Drilling Project (WBDP) and discussed technical and\u0000logistical aspects as well as the scope of the scientific collaboration in\u0000preparation for a full drilling proposal for submission to the International Continental Scientific Drilling Program (ICDP). Workshop participants\u0000mutually agreed to design a two-phase scientific drilling programme that will in a first phase target the upper 3000 m and in a second phase the entire up\u0000to 7500 m thick sedimentary infill of the basin. For the purpose of the 7500 m deep borehole, the world's only drill rig for ultra-deep scientific drilling on land, Crust 1, which previously recovered the entire\u0000continental Cretaceous sediments in the Songliao Basin, will be deployed in\u0000the WBDP.\u0000","PeriodicalId":51840,"journal":{"name":"Scientific Drilling","volume":"30 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2020-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89424200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coring the sedimentary expression of the early Toarcian Oceanic Anoxic Event: new stratigraphic records from the Tethys Ocean","authors":"E. Erba, G. Gambacorta, S. Visentin, L. Cavalheiro, Dario Reolon, G. Faucher, M. Pegoraro","doi":"10.5194/sd-26-17-2019","DOIUrl":"https://doi.org/10.5194/sd-26-17-2019","url":null,"abstract":"Abstract. The Toarcian Oceanic Anoxic Event (T-OAE) interval was cored at Colle di Sogno and Gajum in the Lombardy Basin (Southern Alps, northern Italy). The Sogno and Gajum cores recovered 26.83 and 31.18 stratigraphic metres, respectively, of pelagic sediments consisting of marly limestones, marlstone, marly claystone, and black shale. Drilling at both sites resulted in 100 % recovery of unweathered material. The pelagic succession comprises a relatively expanded black shale interval of 4.98 m in the Sogno core and 15.35 m in the Gajum core, with lower and upper boundaries without evidence of hiatuses. The Sogno and Gajum cores can be considered reference sections for the pelagic lower Toarcian interval of the western Tethys and will provide high-resolution micropaleontological, inorganic and organic geochemical, isotopic multiproxy data. Integrated stratigraphy and cyclostratigraphy are predicted to result in estimates of durations and rates to model the ecosystem resilience to the extreme perturbations of the T-OAE and gain a better understanding of current global changes and help provide better projections of future scenarios.","PeriodicalId":51840,"journal":{"name":"Scientific Drilling","volume":"39 1","pages":"17-27"},"PeriodicalIF":1.2,"publicationDate":"2019-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74079116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}