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Characterization of ultra-deeply buried middle Triassic Leikoupo marine carbonate petroleum system (!) in the Western Sichuan depression, China
Get PDFUltra-deeply buried (>5000 m) marine carbonate reservoirs have gradually become important exploration targets. This research focuses on providing an understanding of the basic elements of the ultra-deeply buried Middle Triassic Leikoupo marine carbonate petroleum system within the Western Sichuan Depression, China. Comprehensive analyses of organic geochemistry, natural gas, and C–H–He–Ne–Ar isotope compositions suggest that the reservoir is charged with compound gases from four source rock units including the Permian Longtan, Middle Triassic Leikoupo, Late Triassic Maantang and Xiaotangzi formations. Approximately a 50-m thick outcrop and 100-m length of drilling cores were examined in detail, and 108 samples were collected from six different exploration wells in order to conduct petrographic and petrophysical analyses. Thin-section and scanning electron microscope (SEM) observations, helium porosity and permeability measurements, mercury injection capillary pressure (MICP) analysis, and wire-line logging (5,500–6,900 m) indicate that the reservoir lithologies include argillaceous algal limestones, dolograinstones, crystalline dolostones, and microbially-derived stromatolitic and thrombolitic dolostones. Reservoir properties exhibit extreme heterogeneity due to different paleogeographic environmental controls and mutual interactions between constructive (e.g., epigenetic paleo-karstification, burial dissolution, structural movement, pressure-solution and dolomitization) and destructive (e.g., physical/chemical compaction, cementation, infilling, recrystallization, and replacement) diagenetic processes. An unconformity-related epigenetic karstification zone was identified in the uppermost fourth member of the Leikoupo Formation, which has developed secondary solution-enhanced pores, vugs, and holes that resulted in higher porosity (1.8–14.2%) and permeability (0.2–7.7 mD). The homogeneity and tightness of the reservoir increases with depth below the unconformity, and it is characterized by primary intergranular and intracrystalline pores, solution pores, fractures, stylolites, and micropores with a lower helium porosity (0.6–4.1%) and permeability (0.003–125.2 mD). Regional seals consist of the Late Triassic Xujiahe Formation, comprised of ~300 m of mudstones that are overlain by ~5,000-m thick of Jurassic to Quaternary continental argillaceous overburden rocks. Effective traps are dominated by a combination of structural-stratigraphic types. Paleo- reservoir crude oil cracking, wet-gases, and dry-gases from three successive hydrocarbon generation processes supplied the sufficient hydrocarbon resources. The homogenization temperatures of the hydrocarbon-associated aqueous fluid inclusions range from 98–130 °C and 130–171 °C, which suggests hydrocarbon charging occurred between 220–170 Ma and 130–90 Ma, respectively. One-dimensional basin evolution models combined with structural geologic and seismic profiles across wells PZ1-XQS1-CK1-XCS1-TS1 show that hydrocarbon migration and entrapment mainly occurred via the unconformity and interconnected fault-fracture networks with migration and charging driven by formation overpressure, abnormal fluid flow pressure, and buoyancy forces during the Indosinian and Yanshanian orogenies, with experiencing additional transformation occurring during the Himalayan orogeny. The predicted estimated reserves reached ~300 × 109 m3. The results provide excellent scientific implications for similar sedimentary basin studies, it is believed that abundant analogous deeply buried marine carbonate hydrocarbon resources yet to be discovered in China and elsewhere worldwide in the near future
Supporting conservationists’ mental health through better working conditions
Get PDFBiodiversity conservation work can be challenging but rewarding, and both aspects have potential consequences for conservationists’ mental health. Yet, little is known about patterns of mental health among conservationists and its associated workplace protective and risk factors. A better understanding might help improve working conditions, supporting conservationists’ job satisfaction, productivity, and engagement, while reducing costs from staff turnover, absenteeism, and presenteeism. We surveyed 2311 conservation professionals working in 122 countries through an internet survey shared via mailing lists, social media, and other channels. We asked them about experiences of psychological distress, working conditions, and personal characteristics. Over half were from and worked in Europe and North America, and most had a university-level education, were in desk-based academic and practitioner roles, and responded in English. Heavy workload, job demands, and organizational instability were linked to higher distress, but job stability and satisfaction with one's contributions to conservation were associated with lower distress. Respondents with low dispositional and conservation-specific optimism, poor physical health, and limited social support, women, and early-career professionals were most at risk of distress in our sample. Our results flag important risk factors that employers could consider, although further research is needed among groups underrepresented in our sample. Drawing on evidence-based occupational health interventions, we suggest measures that could promote better working conditions and thus may improve conservationists’ mental health and abilities to protect nature
Leadership and gender: Impression management in the pictures/photographs and narratives of corporate reporting
Get PDFOn the Correlation of Completion Progress in Virtual Learning Environments and Student Outcomes
Get PDFSampling Reality: Exploring Evidence Accumulation Mechanisms in the Psychotic Phenotype
Get PDFThe way the brain samples evidence could be crucial in shaping ourexperience of reality. Predictive coding accounts hypothesise that increasedsensory precision might bias sampling and impact inferences of reality. In apredictive coding framework integrated with the use of sequential samplingmodels, we investigated the relationship between evidence accumulationmechanisms and psychotic phenotypes in the general population.Study 1 explored the association of psychotic phenotypes with alterations ofevidence accumulation in perceptual inference. We fitted drift-diffusionmodels (DDM) to behavioural data and evaluated the relation betweenpsychotic phenotype and DDM parameters using the drift rate as a proxy ofprecision of sensory evidence. Additionally, we sought to replicate findingslinking reduced data-gathering in probabilistic reasoning with delusion-likeexperiences, a bias known as the Jumping to Conclusions bias (JTC). Resultsshowed that both hallucination- and delusion-like experiences were associatedwith increased sensory precision in perceptual inference. Onlyhallucination-like experiences predicted lower decision thresholds, while wedid not find JTC in the psychotic phenotypes.Study 2 aimed to modulate evidence accumulation by applying inhibitorytranscranial magnetic stimulation (TMS) to the posterior parietal cortex (PPC)and examining its effects along the psychotic phenotype continuum. PPCactivity has been correlated with sampling behaviour and might be involved inalterations of evidence accumulation associated with psychosis. We replicatedresults from Study 1 with both psychotic phenotypes showing increasedsensory precision. Notably, participants with a higher delusional phenotypeundergoing TMS showed decreased sensory precision.In conclusion, our findings indicate that increased precision of sensoryevidence characterises perceptual inference in both delusional andhallucinatory phenotypes. Specifically for the delusional phenotype, PPCactivity might be implicated in alterations of precision encoding. Overall, ourstudies point to evidence accumulation mechanisms potentially influencingour experience of reality and contributing to the psychotic phenotype in thegeneral populatio
Counterfeits (Siminica) co-created by Laurence Osborn and Zubin Kanga
Get PDFThis work composed by Laurence Osborn in collaboration with Zubin Kanga, combines the TouchKeys technology on a keyboard, with vocal samples created by the composer to imitate the Romanian folk singer, Siminica. The TouchKeys keyboard facilitates the bending of pitch by sliding the finger across the key, which in this case is used to allow the keyboard to imitate the vocal sounds of a folk singer
A Graph Neural Networks-Based Learning Framework With Hyperbolic Embedding for Personalized Tag Recommendation
Get PDFLearning high-quality representations of users, items, and tags from historical interactive data is crucial for personalized tag recommendation (PTR) systems. Currently, most PTR models are committed to learning representations from first-order interactions without considering the exploitation of high-order interactive relations, which can be beneficial for avoiding sub-optimal learning. Although several PTR models equipped with graph neural networks (GNN) have been proposed to capture higher-order semantic relevance from raw data, they all carry out representation learning in Euclidean space, which can still easily result in sub-optimal learning due to embedding distortion. In order to further improve the quality of representation learning for PTR, the paper proposes a novel PTR model based on a lightweight GNN framework with hyperbolic embedding, namely GHPTR. GHPTR explicitly injects higher-order relevance into entity representation through the message propagation and aggregation mechanism of GNN and leverages hyperbolic embedding to alleviate the embedding distortion problem. Experimental results on real-world datasets have demonstrated the superiority of our model over its Euclidean counterparts and state-of-the-art baselines
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