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"Geological time"
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Geoscience knowledge graph in the big data era
Since the beginning of the 21st century, the geoscience research has been entering a significant transitional period with the establishment of a new knowledge system as the core and with the drive of big data as the means. It is a revolutionary leap in the research of geoscience knowledge discovery from the traditional encyclopedic discipline knowledge system to the computer-understandable and operable knowledge graph. Based on adopting the graph pattern of general knowledge representation, the geoscience knowledge graph expands the unique spatiotemporal features to the Geoscience knowledge, and integrates geoscience knowledge elements, such as map, text, and number, to establish an all-domain geoscience knowledge representation model. A federated, crowd intelligence-based collaborative method of constructing the geoscience knowledge graph is developed here, which realizes the construction of high-quality professional knowledge graph in collaboration with global geo-scientists. We also develop a method for constructing a dynamic knowledge graph of multi-modal geoscience data based on in-depth text analysis, which extracts geoscience knowledge from massive geoscience literature to construct the latest and most complete dynamic geoscience knowledge graph. A comprehensive and systematic geoscience knowledge graph can not only deepen the existing geoscience big data analysis, but also advance the construction of the high-precision geological time scale driven by big data, the compilation of intelligent maps driven by rules and data, and the geoscience knowledge evolution and reasoning analysis, among others. It will further expand the new directions of geoscience research driven by both data and knowledge, break new ground where geoscience, information science, and data science converge, realize the original innovation of the geoscience research and achieve major theoretical breakthroughs in the spatiotemporal big data research.
Journal Article
Global patterns of β-diversity along the phylogenetic time-scale: The role of climate and plate tectonics
Aim: We aimed to assess the relative influence of the historical and contemporary processes determining global patterns of current β-diversity. Specifically, we quantified the relative effects of contemporary climate and historical plate tectonics on β-diversity at different phylogenetic scales. Location: Global. Time Period: Contemporaneous. Major taxa studied: Mammals and birds. Methods: We analysed the current β-diversity patterns of birds and mammal assemblages at sequential depths in the phylogeny, that is, from the tips to deeper branches. This was done by slicing bird and mammal phylogenetic trees into 66 time slices of 1 Ma (from 0 to 65 Ma) and recording the branches within each slice. Using global distribution data, we defined the branches' geographical distribution as the union of the corresponding downstream species distributions. For each time slice, we (a) computed pairwise β-diversity across all the grid cells for the whole world and (b) estimated the correlation between this β-diversity matrix and contemporary climatic and geographical distances, and past geological distances, a proxy for plate tectonics. Results: Contemporary climate best explained the β-diversity of shallow branches (i.e., species). For mammals, the geographical isolation of landmasses generated by plate tectonics best explained the β-diversity of deeper branches, whereas the effect of past isolation was weaker for birds. Main conclusions: Our study shows that the relative influence of contemporary climate and plate tectonics on the β-diversity of bird and mammal assemblages varies along the phylogenetic time-scale. Our phylogenetic time-scale approach is general and flexible enough to be applied to a broad spectrum of study systems and spatial scales.
Journal Article
A lunar time scale from the perspective of the Moon’s dynamic evolution
A geologic time scale is a chronological system that separates the geological strata of a planetary body into different units in temporal sequence and shows its progressive evolution. The time scale of the Moon was established a half-century ago during the telescopic-early Apollo exploration era, using data with limited spatial coverage and resolution. The past decades have seen a wide array of studies, which have significantly extended our understanding of global lunar geologic evolution. Based on a comprehensive review of lunar evolution with respect to the dynamical changes, we propose two major updates to the current lunar time scale paradigm to include the evolution of both endogenic and exogenic dynamic forces now known to have influenced early lunar history. Firstly, based on the temporal interplay of exogenic and endogenic processes in altering the Moon, we defined three Eon/Eonothem-level units to represent three dynamical evolutionary phases. Secondly, the pre-Nectarian System is redefined and divided as the magma ocean-era Magma-oceanian System and the following Aitkenian System beginning with the South Pole-Aitken basin. The ejecta of this basin, Das Formation, was deposited on the primordial lunar crust as the oldest stratum produced from exogenic processes. The updated lunar time scale, facilitated by the post-Apollo exploration and research advances, provides an integrated framework to depict the evolution of the Moon and has important implications for the geologic study of other terrestrial planets.
Journal Article
Geological Time Perspective and Pro-Environmental Decision-Making: A Structural Equation Model Exploring Temporal Construal Level as a Cognitive Mediator
This study employs a sequential mediation model to investigate the cognitive mechanisms linking Earth science education to sustainable behavior. Grounded in construal level theory and temporal cognition research, we hypothesize that geological time perception mediates the relationship between Earth science education and temporal construal level, which in turn affects sustainable behavior. Structural equation modeling, based on data from 280 participants, validated the proposed model. It confirmed geological time perception as a second-order construct with four dimensions: time span perception, understanding of geological processes, time depth perception, and continuity of geological change. The results indicated significant indirect pathways. Earth science education influenced the temporal construal level via geological time perception (β = 0.325), and the temporal construal level mediated the relationship between geological time perception and sustainable behavior (β = 0.306). The sequential mediation path (β = 0.215) suggests that Earth science education promotes sustainable behavior by recalibrating temporal cognition and construal processes. This finding illuminates how educational interventions can address the temporal asymmetry in environmental decision-making by developing specific cognitive capacities rather than simply imparting knowledge.
Journal Article
A New Period for the Geologic Time Scale
The geologic time scale stands as a major achievement of the 19th-century science, a coherent record of the Earth's history fashioned from myriad details of individual rock outcroppings. Last March, the International Union of Geological Sciences approved the addition of the Ediacaran Period to the geologic time scale. This newly ratified period, which directly precedes the Cambrian, is the first Precambrian interval to be defined by an event recorded in a single section of rock outcropping termed the global stratotype section and point.
Journal Article