During the last twenty years, several technical developments have considerably intensified the use of numerical dating methods for the Quaternary. The study of fluvial archives has greatly benefited ...from these enhancements, opening new dating horizons for a range of archives at distinct time scales and thereby providing new insights into previously unanswered questions. In this contribution, we separately present the state of the art of five numerical dating methods that are frequently used in the fluvial context: radiocarbon, Luminescence, Electron Spin Resonance (ESR), 230Th/U and terrestrial cosmogenic nuclides (TCN) dating. We focus on the major recent developments for each technique that are most relevant for new dating applications in diverse fluvial environments and on explaining these for non-specialists. Therefore, essential information and precautions about sampling strategies in the field and/or laboratory procedures are provided. For each method, new and important implications for chronological reconstructions of Quaternary fluvial landscapes are discussed and, where necessary, exemplified by key case studies. A clear statement of the current technical limitations of these methods is included and forthcoming developments, which might possibly open new horizons for dating fluvial archives in the near future, are summarised.
•We present the state of the art of five numerical dating methods, frequently used in the fluvial context.•The methods are: 14C, Luminescence, Electron Spin Resonance, U-series and terrestrial cosmogenic nuclides dating.•We focus on the major recent developments, relevant for new dating applications in diverse fluvial environments.•Current technical limitations and forthcoming developments are also tackled.
Within the last decade, the high and continuing demand for precious and base metals, as well as critical elements, has prompted a global rush on a scale never before seen. This eventually resulted in ...the demand for considerable innovation and improvement in mineral deposit genetic modelling and ore formation regimes for the many different types of gold deposits, now recognized, and paralleled by the wide employment of exploration techniques and a rapid expansion of geological databases.
This Special Issue will show case studies of porphyry polymetal systems, orogenic gold formations, water–rock reaction, ore-forming structure evolution, mineralogy and petrology of ore deposit, ore formation regime, geochronology and geochemistry of ore deposit, ore-forming evolution, mineral exploration and cutting-edge technology in ore deposit study.
An examination of dating app culture in China, across user demographics—straight women, straight men, queer women, and queer men. In this exploration of dating app culture in China, Lik Sam Chan ...argues that these popular mobile apps are not merely a platform for personal relationships but also an emerging arena for gender and queer politics. Chan examines the opportunities dating apps present for women's empowerment and men's performances of masculinity, and he links experiences of queer dating app users with their vulnerable position as sexual minorities. He finds that dating apps are both portals to an exciting virtual world of relational possibilities and sites of power dynamics that reflect the heteronormativity and patriarchy of Chinese society. Drawing on in-depth interviews with urban users of such dating apps as Momo, Tantan, Blued, Aloha, Rela, and Lesdo, Chan proposes “networked sexual publics” as a unifying concept to capture the dynamics of dating app culture. Devoting a chapter to each of four publics—straight women, straight men, queer men, and queer women—Chan documents how relationships are shaped and transfigured by this emerging technology. He considers whether dating apps can be a feminist tool; explores straight men's self-presentation on the apps and their interactions with women they meet there; discusses the constant cycle of deleting and installing the same apps seen among queer men; and examines how popular lesbian dating apps may connect queer women to their communities. Finally, Chan maps possible paths for future intersectional, queer, and feminist scholarship on emerging communication technologies.
Data Dating Malinowska, Ania; Peri, Valentina
2021
eBook
Organized around ten chapters and works of new media art, the collection offers an extensive critical analysis of technologized romance - and other emotional relations - as well as provides an ...insight into the codification, execution, deployment and evolution of the patterns of togetherness in the so-called Tamagotchi era. 45 col. photographs.
The coronavirus disease-19 pandemic introduced a crisis of safety and relevance for dating apps, as their affordances for facilitating in-person encounters posed the risk of viral transmission. This ...article examines how eight apps primarily catering to heterosexual markets responded to the pandemic through changes to socio-technical arrangements, new user prescriptions, and the curation of corporate data and success stories. By analyzing corporate social media and promotional materials alongside in-app developments, we find that these companies reimagined app affordances to promote “virtual dating,” a set of practices and symbolic meanings that prioritize visual, synchronous digital interaction as the most responsible, reliable, and successful dating approach to the pandemic. Virtual dating centers apps as databases of potential partners while prescribing modes of use aimed toward affective relief, displays of authenticity, and romantic courtship. This reimagining counters moral panics about digitally mediated relationships by resorting to heteronormative dating scripts while overlooking alternative app uses.
Dating the transport/deposition time of supratidal coarse-clast deposits is difficult, limiting their value for inferring frequency-magnitude patterns of high-energy wave events. On Bonaire (Leeward ...Antilles, Caribbean), these deposits form prominent landforms, and transport by one or several Holocene tsunamis is assumed at least for the largest clasts. Although a large dataset of 14C and electron spin resonance (ESR) ages is available for major coral rubble ridges and ramparts, it is still debated whether these data reflect the timing of major events, and how these datasets are biased by the reworking of coral fragments. As an attempt to overcome the current challenges for dating the dislocation of singular boulders, three distinct dating methods are implemented and compared: (i) 14C dating of boring bivalves attached to the boulders; (ii) 230Th/U dating of post-depositional, secondary calcite flowstone and subaerial microbialites at the underside of the boulders; and (iii) surface exposure dating of overturned boulders via 36Cl concentration measurements in corals. Approaches (ii) and (iii) have never been applied to coastal boulder deposits so far. The three 14C age estimates are older than 40ka, i.e. most probably beyond the applicability of the method, which is attributed to post-depositional diagenetic processes, shedding doubt on the usefulness of this method in the local context. The remarkably convergent 230Th/U ages, all pointing to the Late Holocene period (1.0–1.6ka), are minimum ages for the transport event(s). The microbialite sample yields an age of 1.23±0.23ka and both flowstone samples are in stratigraphic order: the older (onset of carbonate precipitation) and younger flowstone layers yield ages of 1.59±0.03 and 1.23±0.03ka, respectively. Four coral samples collected from the topside of overturned boulders yielded similar 36Cl concentration measurements. However, the computed ages are affected by large uncertainties, mostly due to the high natural chlorine concentration. After correction for the inherited component and chemical denudation since platform emergence (inducing additional uncertainty), the calculated 36Cl ages cluster between 2.5±1.3 and 3.0±1.4ka for three of four boulders whilst the fourth one yields an age of 6.1±1.8ka, probably related to a higher inheritance. These 230Th/U and 36Cl age estimates are coherent with a suggested tsunami age of <3.3ka obtained from the investigation of allochthonous shell horizons in sediment cores of northwestern Bonaire. Whilst 230Th/U dating of post-depositional calcite flowstone appears to be the most robust and/or accurate approach, these results illustrate the potential and current limitations of the applied methods for dating the dislocation of supralittoral boulders in carbonate-reef settings.
Numerous studies have now demonstrated that the most common method of ageing sharks and rays, counting growth zones on calcified structures, can underestimate true age. I reviewed bomb carbon dating ...(n = 15) and fluorochrome chemical marking (n = 44) age validation studies to investigate the frequency and magnitude of this phenomenon. Age was likely to have been underestimated in nine of 29 genera and 30% of the 53 populations studied, including 50% of those validated using bomb carbon dating. Length and age were strongly significant predictors of occurrence, with age typically underestimated in larger and older individuals. These characteristics suggest age underestimation is likely a systemic issue associated with the current methods and structures used for ageing. Where detected using bomb carbon dating, growth zones were reliable up to 88% of asymptotic length (L∞) and 41% of maximum age (AMax). The maximum magnitude of age underestimation, ΔMax, ranged from five to 34 years, averaging 18 years across species. Current perceptions of shark and ray life histories are informed to a large extent by growth studies that assume calcified ageing structures are valid throughout life. The widespread age underestimation documented here shows this assumption is frequently violated, with potentially important consequences for conservation and management. In addition to leading to an underestimation of longevity, the apparent loss of population age‐structure associated with it may unexpectedly bias growth and mortality parameters. Awareness of these biases is essential given shark and ray population assessments often rely exclusively on life history parameters derived from ageing studies.
Radiocarbon dating is the most widely applied dating method in archaeology, especially in human evolution studies, where it is used to determine the chronology of key events, such as the replacement ...of Neanderthals by modern humans in Europe. However, the method does not always provide precise and accurate enough ages to understand the important processes of human evolution. Here we review the newest method developments in radiocarbon dating ('Radiocarbon 3.0'), which can lead us to much better chronologies and understanding of the major events in recent human evolution. As an example, we apply these new methods to discuss the dating of the important Palaeolithic site of Bacho Kiro (Bulgaria).
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