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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.

As an important contributor to the habitability of our planet, the oxygen cycle is interconnected with the emergence and evolution of complex life and is also the basis to establish Earth system science. Investigating the global oxygen cycle provides valuable information on the evolution of the Earth system, the habitability of our planet in the geologic past, and the future of human life. Numerous investigations have expanded our knowledge of the oxygen cycle in the fields of geology, geochemistry, geobiology, and atmospheric science. However, these studies were conducted separately, which has led to one-sided understandings of this critical scientific issue and an incomplete synthesis of the interactions between the different spheres of the Earth system. This review presents a five-sphere coupled model of the Earth system and clarifies the core position of the oxygen cycle in Earth system science. Based on previous research, this review comprehensively summarizes the evolution of the oxygen cycle in geological time, with a special focus on the Great Oxidation Event (GOE) and the mass extinctions, as well as the possible connections between the oxygen content and biological evolution. The possible links between the oxygen cycle and biodiversity in geologic history have profound implications for exploring the habitability of Earth in history and guiding the future of humanity. Since the Anthropocene, anthropogenic activities have gradually steered the Earth system away from its established trajectory and had a powerful impact on the oxygen cycle. The human-induced disturbance of the global oxygen cycle, if not controlled, could greatly reduce the habitability of our planet.

Geological samples must be archived for all if we are to solve the riddles of Earth’s complex history. Geological samples must be archived for all if we are to solve the riddles of Earth’s complex history.

The Lopingian is one of the fastest rising periods of seawater strontium isotopic ratios (87Sr/86Sr) in earth history, and its mechanisms and increasing rates of the 87Sr/86Sr evolution were still disputed widely. These disputations among researchers were caused mainly by timeframe selection (sections’ thickness or data of radiometric ages), and different stratigraphic boundaries and un-upmost dated ages. This paper examined published 87Sr/86Sr data of the Lopingian, and projected them on timescales based on evolutionary and age constrained conodonts fossils. 87Sr/86Sr evolution vs fossil constraining timescales was re-established in this period. This research suggests: (1) 87Sr/86Sr excursion projects on fossil zones can truly support 87Sr/86Sr evolutionary pattern in the period; (2) 87Sr/86Sr evolution provides a new approach for stratigraphic research of marine carbonate sections in lieu of biostratigraphic data; (3) 87Sr/86Sr stratigraphy works on marine carbonate sections of different sedimentation rates even between different basins; (4) the 87Sr/86Sr data and its shift was dependent on samples materials and chemical treatment methods; (5) the increasing rate of marine water 87Sr/86Sr in the Late Permian is suggested as 5.4×10−5/Ma or slightly lower; (6) sedimentation age and its 87Sr/86Sr of the Lopingian marine carbonate suggested as: DPRO=259-(RS−0.70695)/5.4×10−5±1 Ma.

The Neoproterozoic-Cambrian (N-C) and Permian-Triassic (P-T) transitions have been regarded the two most critical transitions in earth history because of the explosive biological radiation in the early Cambrian (the Cambrian Explosion) and the largest mass extinction at the end-Permian. Previous studies suggest that these two critical transitions showed certain comparability in major evolutionary events. In other words, a series of biological, geological, and geochemical events that had happened in the N-C transition occurred repeatedly during the P-T transition. Those events included continental re-configuration related to the deep mantle dynamics, global-scale glaciations, large C-, Sr-, and S-isotope perturbations indicating atmospheric and oceanic changes, abnormal precipitation of carbonates, and associated multiple biological radiations and mass extinctions. The coupling of those events in both N-C and P-T transitions suggests that deep mantle dynamics could be a primary mechanism driving dramatic changes of environment on the earth’s surface, which in turn caused major biological re-organizations. A detailed comparison of those events during the two critical transitions indicates that despite their general comparability, significant differences do exist in magnitude, duration, and frequency. The supercontinent Rodinia began to rift before the Snowball Earth time. By contrast, the supercontinent Pangea entered the dispersal stage after the greatest glaciation from the Late Carboniferous to Cisuralian. Quantitative data and qualitative analyses of different fossil groups show a more profound mass extinction during the N-C transition than at the end-Permian in terms of ecosystem disruption. This is indicated by the disappearance of the whole Ediacaran biota at the N-C boundary. The subsequent appearances of many new complex animals at phylum level in the early Cambrian mark the establishment of a brand new ecosystem. However, the end-Permian mass extinction is manifested mainly by the extinction of many different taxa at class and order levels. Although it caused the extinction of 95% of marine species and 75% of terrestrial species as well as complete cessation of coal and reef deposits after the mass extinction, this high-level biological re-organization still occurred within an established ecosystem, however drastic it may seem. Survived or Lazarus taxa re-occupied the existing ecospace in a relatively short duration after the end-Permian mass extinction. C-isotope excursions display large perturbations during both transitions, yet also in different magnitudes and frequencies, which suggest different atmospheric and oceanic conditions. The recurrent geological and geochemical events as well as the coupled major biological turnovers during the two transitions provide new clues to understanding the interplays among the earth-life system. Thus, it is essential to carry out multidisciplinary studies from the deep internal system to the surface of the Earth as a whole in order to unravel the interactions of different spheres of the earth.