The determination of rank positions for institutions is based on a sum of D-indexes (Discipline H-index) of all researchers whose main field of publication is Earth Science and who are affiliated with a given institution. It is important to emphasize that the D-index accounts solely for publications and citations within the targeted discipline, ensuring an accurate reflection of Earth Science research impact.
Scope of Research and Inclusion Criteria
A rigorous selection process was followed for the 2024 edition. From an initial dataset of 279,971 scientist profiles identified across various bibliometric sources, detailed analysis was conducted on 31,170 scientists specifically within the field of Earth Science.
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Each scientist considered for the ranking was required to meet a qualifying D-index threshold of 30, with the majority of their major publications recorded in Earth Science.
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In addition to citation-based metrics, scientists' awards and professional achievements in the field were also evaluated.
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The D-index threshold for evaluating leading researchers increases in increments of 10, calibrated according to the total number of scholars estimated in each discipline, thereby ensuring the top 1% of researchers are represented in the listing.
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The proximity between an individual’s general H-index and their D-index needed to be 30% or less, further ensuring the focus remains on subject-area excellence.
Inclusion was anchored in both quantitative and qualitative assessments, providing a robust foundation for the ranking.
Verification and Methodological Rigor
We understand that raw bibliometric data should not be the sole basis for evaluating research output. To add further credibility, all scientist profiles underwent manual verification and were cross-validated against publications listed in a wide spectrum of trusted sources.
Although the number of publications in high-impact journals and conference proceedings does not directly affect a scientist’s rank in the Research.com listing, it serves as an important secondary indicator of research contribution within the discipline.
Institutional rankings are determined using each researcher’s H-index as reported by OpenAlex and CrossRef—databases that are regarded as the gold standard among the scholarly community for tracking author-level metrics. For those interested in exploring our process in detail, please see our methodology page.
About the Research.com Ranking Initiative
At Research.com, our mission is to inspire scientists, business professionals, and policymakers to track the direction of top experts globally. By providing transparent and accessible rankings, we aim to support the entire research community in discerning who the leading contributors are across various disciplines, countries, and research institutions. The ultimate objective is to promote informed decision-making and to foster a thriving environment for scientific exchange and innovation.
Key Results: Earth Science University Research Ranking in Tunisia and Global Highlights
Top Universities in Tunisia:
- University of Gafsa: 1 leading scientist in Earth Science
- University of Sfax: 1 leading scientist in Earth Science
International Comparison: The most prominent scholars in Earth Science in the world are affiliated with distinguished institutions such as Brown University, KU Leuven, Macquarie University, Curtin University, Utrecht University, University of Colorado Boulder, University of Hong Kong, China University of Geosciences, Xi'an Jiaotong University, and the University of Bristol.
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Professor James W. Head (Brown University) is ranked as the top scientist globally, with a D-index of 148.
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The second position is held by Jean Poesen (KU Leuven), with a D-index of 147.
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The third spot is taken by William L. Griffin (Macquarie University), with a D-index of 144.
Aggregate Metrics:
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Average total D-index for the top 5% of universities: 2,404 (versus 377 for all 822 institutions included in the ranking)
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Average number of published articles in Earth Science for the top 5% of universities: 9,544 (versus 1,521 for all 822 institutions)
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Average number of citations for the top 1% of universities: 279,971 (versus 80,226 for all 822 institutions)
These results underscore both the diligence with which this ranking has been compiled and the prominence of the leading institutions and scholars in the field. Research.com remains committed to supporting transparent, evidence-based recognition of scientific excellence.
