Marine Geohazards: A Bibliometric-Based Review

A bibliometric and content analysis of research trends on GIS-based landslide susceptibility from 2001 to 2020

To assess the status of hotspots and research trends on geographic information system (GIS)-based landslide susceptibility (LS), we analysed 1142 articles from the Thomas Reuters Web of Science Core Collection database published during 2001-2020 by combining bibliometric and content analysis. The paper number, authors, institutions, corporations, publication sources, citations, and keywords are noted as sub/categories for the bibliometric analysis. Thematic LS data, including the study site, landslide inventory, conditioning factors, mapping unit, susceptibility models, and mode fit/prediction performance evaluation, are presented in the content analysis. Then, we reveal the advantages and limitations of the common approaches used in thematic LS data and summarise the development trends. The results indicate that the distribution of articles shows clear clusters of authors, institutions, and countries with high academic activity. The application of remote sensing technology for interpreting landslides provides a more convenient and efficient landslide inventory. In the landslide inventory, most of the sample strategies representing the landslides are point and polygon, and the most frequently used sample subdividing strategy is random sampling. The scale effects, lack of geographic consistency, and no standard are key problems in landslide conditioning factors. Feature selection is used to choose the factors that can improve the model's accuracy. With advances in computing technology and artificial intelligence, LS models are changing from simple qualitative and statistical models to complex machine learning and hybrid models. Finally, five future research opportunities are revealed. This study will help investigators clarify the status of LS research and provide guidance for future research.

Geoheritage and Geosites: A Bibliometric Analysis and Literature Review

Geological heritage represents and brings together geological elements of great local and global relevance. It also promotes conservation and sustainable use. This study aims to perform a bibliometric analysis of the contributions that address the topics of geological heritage and geosites, using the Scopus and Web of Science databases for the knowledge of trends and research focuses in this area. The methodology consists of: (i) the preparation of the idea and gathering information from a search on the subjects of interest (geoheritage and geosites); (ii) the merging of the databases and applying automated conversions; and (iii) the analysis of the results and the literature review. The first phase of the work identified 2409 and 1635 documents indexed in Scopus and WoS, respectively. The merged global database (2565 documents) identified the following words as analysis topics: geoconservation, geotourism, geopark, and geodiversity. The analysis also revealed the top five countries in scientific contributions as Italy (12.1%), Spain (8.77%), China (5.67%), Portugal (5.35%), and Brazil (5.31%). Finally, most of the publications focus on the characterisation, assessment, and development of geosite initiatives. The main lines of action and contributions to the topics (7.91%) highlight the fact that geoscientists worldwide value geosites for geoconservation and geotourism strategies.

Rockfall Research: A Bibliometric Analysis and Future Trends

Rockfall is one of the main phenomena in mountainous environments due to its fast and high speed of movement, its unpredictability, and, therefore, the difficulty of identifying signs of instability and detachment of the blocks. Compared to other types of sliding, the proportion of rockfall research is smaller and sometimes little known, but, in the last five years, rapid growth in this area has been shown. Therefore, this research aimed to review the intellectual structure of rockfall, through analysis of scientific production using bibliometric techniques that allow its analysis, knowledge, global evolution, and future trends in rockfall. The research methodology consists of three steps: (1) data compilation, (2) software and data cleaning, and (3) analysis, interpretation, and visualization. This analysis focuses on the period from 1975 to 2019. For the data, a total of 811 academic publications were retrieved from the Scopus database. The results indicate an increasing trend of annual publications on rockfall. This analysis reveals the main topics, countries, and most influential institutions in the world that have carried out relevant research in scientific publications; it also shows the journals that have the most publications. VOSviewer software was adopted to evaluate the co-occurrence of author keywords. Currently, the hotspots rockfall issues mainly include: hazard-risk assessment, remote sensing, and rockfall monitoring. Finally, this article analyzes the limitations of current research and proposes a future direction for the development of new research.

Volcanic Geomorphology: A Review of Worldwide Research

The purpose of this article is to provide an overview of academic research on volcanic geomorphology, through the use of bibliometric analysis and bibliographic visualization maps for the discernment of its growing interest by the academy in the last 30 years. It is sustained on the publications indexed in the Scopus database between 1956 and 2019, obtaining relevant information on scientific production, following the methodological structure of a rigorous bibliometric process, which ranges from the search for descriptors or keywords to the configuration of visualizations of tables and maps that allowed to consider the contributions by authors, institutions, journals and topics that have shaped the evolution of this field of study. The generations of bibliometric maps allowed understanding the intellectual structure of the field of study made up of 707 articles where the analysis of co-occurrence of author keywords showed six main lines of research that, combined with the co-citation maps, allowed understanding the breadth of intellectual structure. Extensive information is provided on the thematic that other investigations partially addressed or failed to capture their current status. Considering that the results allow us to identify areas of current interest and the potential of research in volcanic geomorphology.

An Assessment of Stress States in Passive Margin Sediments: Iterative Hydro-Mechanical Simulations on Basin Models and Implications for Rock Failure Predictions

Capturing the past and present hydro-mechanical behavior of passive margin sediments raises noticeable interest, notably in geo-hazard risk assessment and hydrocarbon exploration. In this work, we aim at assessing the stress states undergone by these sedimentary deposits through geological time. To do so, we use an iterative coupling between a basin simulator and a finite element mechanical solver. This method conciliates a computation of the full stress tensors with a dynamic and geologically detailed modelling of the sedimentation. It is carried out on a dedicated set of 2D synthetic basin models, designed to be representative of siliciclastic deposition in passive margins and integrating variations in their geological history. Contrary to common assumptions in operational basin modelling studies, our results imply that passive margin sedimentary wedges are multidimensional mechanical systems, which endure significant non-vertical stress without external tectonic input. Our results also highlight the variability of the stress states through space and time, with a strong control from the geometry and lithological heterogeneities of the deposits. Lastly, we used the simulation results to predict a location and timing for the development of weakness zones in the sedimentary stacks, as privileged areas for rock failure. The outcome underlines the influence of the basal tilt angle, with a slight tilt impacting the wedges stability to a similar extent as a substantial increase in sedimentation rate. Altogether, this study emphasizes the need for careful consideration of non-vertical stresses in basin simulations, including in passive tectonic contexts. It also suggests that the iterative coupling method employed is a promising way to match industrial needs in this regard.