Who Shaped Portuguese Geology? Consensus Rankings of the Most Influential Geoscientists Across Seven Chronological and Thematic Domains

1. Introduction

The question of who shaped a scientific discipline, that is, which researchers’ contributions are considered by the community to be most relevant to the construction of knowledge in each domain, is not merely of historical or ceremonial interest. It has practical implications that extend beyond the scientific community itself, for the transmission of knowledge to new generations of researchers, for science education and outreach to non-specialist audiences, namely school students and teachers, and for the collective identity of a scientific community [1,2]. The answer to this question constitutes what may be termed disciplinary memory: the collective, shared, and socially mediated recognition of the figures a community regards as foundational or structuring for its field, a recognition that, once systematized, can also inform how the history of the discipline is communicated to broader publics.

The geosciences in Portugal constitute a field with a documented history of at least two centuries, from the pioneering investigations of Carlos Ribeiro and Nery Delgado into the geology of the mainland territory in the 19th century, through the consolidation of institutional geology in the early 20th century, with the contributions of Paul Choffat to Mesozoic stratigraphy and of Georges Zbyszewski to the Cenozoic and to the geology of the Atlantic islands, up to the rapid expansion of the geoscientific community in the final decades of the 20th century [3,4,5,6]. These contributions already allow chronologically well-differentiated layers to be identified in the constitution of the Portuguese geoscientific community. The relatively contained size of this community (approximately 230 geoscientists affiliated with Portuguese public universities, the population identified for this study) allows, in principle, a comprehensive survey of its members, and offers an opportunity to continue this work of historical reconstruction, now investigating, empirically and systematically, the patterns of collective recognition that these chronological layers reflect.

The interpretation of the recognition patterns identified here draws on the theory of collective memory developed by Halbwachs [7], according to which memory is never purely individual but is always shaped by the social groups to which individuals belong. Applied to scientific communities, this perspective suggests that the recognition of predecessors is a collective achievement, mediated by the discipline’s social structure, its institutions, mentoring networks, and pedagogical traditions. Zerubavel [8] deepened this framework with the concept of the mnemonic community: the social group that shares and transmits a specific memory, determining which figures remain visible and which fade as generations succeed one another. These perspectives provide the theoretical framework for interpreting the patterns of presence and absence of historical figures in the consensus rankings presented here.

The recent renewal of studies on scientific memory has deepened understanding of the mechanisms by which certain figures become canonical while others are forgotten. Daston [9] argued that scientific canonization is an active process of social selection, not a passive sedimentation of merit: the figures who persist in disciplinary memory are those who have been the subject of biographical narratives, institutional tributes, and inclusion in training curricula, a mechanism that operates not only within higher education, but also, and perhaps more decisively, in basic and secondary science education, where most citizens form their only lasting image of a scientific field and its historical protagonists. From this perspective, the absence of biographical systematization is not neutral; it is itself a factor eroding memory, both within the specialized community and in how the discipline is transmitted to pre-university students and teachers. Complementarily, Raj [10] and other historians of science have highlighted how disciplinary recognition is geographically situated: researchers on the periphery, who worked in minority territories or languages, tend to be under-represented in the discipline’s collective memories, even when their contributions are comparable to those of researchers from more visible centers. The Portuguese geosciences illustrate this dynamic: figures such as Carlos Ribeiro or Nery Delgado, whose work achieved international recognition in their time [3], are historiographically documented as having received comparatively limited posterior attention in institutional commemoration and training curricula, illustrating how, in the absence of active cultural mediators, initial recognition may fail to translate into lasting presence in the collective consciousness of a scientific community.

The sociology of scientific recognition has shown, in recent decades, that a researcher’s visibility depends not only on the intrinsic quality of their contributions but also on structural factors such as institutional position, collaboration network, and the historical moment in which the work appears [11,12]. In the geosciences, this structural dimension of recognition has mainly been explored through bibliometric studies of international journals and authors but rarely applied at the scale of national communities or to the recognition of historical figures whose work predates the era of indexed publications [13,14].

To the best of our knowledge, there is to date no evidence-based systematization of the collective recognition of the geoscientists who have contributed to the study of Portuguese geology, a group that includes both Portuguese-born researchers and the foreign scientists, particularly numerous among the discipline’s founding generations, who conducted their work on Portuguese territory or on Portuguese geological problems. Published works on the history of geology in Portugal cover specific periods and figures but were produced by a restricted number of authors following their own editorial criteria, and do not necessarily reflect the consensus of the wider geoscientific community. Conventional bibliometric methods (citation counts, co-citation networks, h-indices) are problematic to apply to historical figures whose work predates digital databases, to researchers in applied contexts whose impact is not reflected in indexed publications, and to small communities where bibliometric signals are statistically noisy [15,16].

The inadequacy of bibliometric methods for small scientific communities and for historical figures has been increasingly documented in the recent literature. Fortunato et al. [17] demonstrated that citation-based impact metrics systematically favor researchers from countries and institutions with higher publication volume, creating structural biases that do not reflect the actual contribution to the field. The Leiden Manifesto [18] systematized precisely these limitations, arguing that universal metrics such as the h-index produce systemic distortions when applied to contexts where the community of potential citers is intrinsically small — exactly the case of national geosciences, where the universe of researchers who could cite a given work is on the order of hundreds rather than thousands, as reflected in the population of approximately 230 geoscientists identified for the present study (see Section 2.1).

This limitation is not exclusive to bibliometrics: it is a manifestation of a more general epistemological problem, already identified by Reynaud [19] (p. 17) with regard to observation methods in the geosciences: “Que voit-il [le chercheur]? Essentiellement ce qu’il cherche!” [“What does the researcher see? Essentially what he is looking for!”]. A method for detecting scientific recognition that looks for citations can only find citable recognition; a method that looks for the living memory of a community, through its own voice, necessarily finds something different. And it is this distinction that this article explores.

In response to these limitations, alternative approaches centered on the community’s own perception have emerged: so-called peer assessment or expert elicitation surveys, which capture recognition as it exists in the consciousness of practitioners, independently of its bibliometric expression [20]. This approach has recently been applied in geoheritage and geoconservation contexts to identify the sites and contributions most relevant according to the specialized community itself [21], suggesting its suitability for analogous purposes in the historiography of the geosciences.

It is in this context that expert nomination surveys offer a methodological alternative with specific advantages: they capture recognition as it exists in the community’s consciousness, they include historical figures regardless of their presence in digital databases, and they allow multiple thematic and geochronological terrains to be covered systematically [22]. This method has precedents in other scientific fields, notably in medicine through Delphi panels [23,24] and in the social sciences for identifying reference works and authors [25]. By capturing recognition as it is lived by the contemporary community, this type of survey can also reveal tensions between peers’ current perception and consolidated historiographical narratives, contributing to a critical and updated reading of disciplinary memory, and not merely to its confirmation.

This article reports the methodology and descriptive results of the project Geology of Portugal through Faces (GeoFaces), which applied a structured nomination survey to 45 geoscientists affiliated with Portuguese public universities, organized into seven chrono-thematic domains. The specific objectives are: (1) to describe the methodology for data collection and processing, including name normalization and the criteria for constructing the rankings; (2) to present complete descriptive statistics for each domain, including the distribution of nominations, the degree of concentration within the biographical corpus, and the characteristics of the nomination lists; (3) to present the consensus rankings by domain, with an analysis of the internal structure of each ranking; (4) construction of a biographical corpus. The analysis of the associations between respondents’ profiles and nomination patterns is the subject of a separate article.

2. Materials and Methods

2.1. Survey Design

The survey was developed within the scope of the GeoFaces project, implemented at the University of Aveiro (Portugal) and structured into two sections. The first section collected sociodemographic and academic-professional information about the respondents: sex, nationality, doctoral degree (yes/no, institution, year), habilitation title, institutional affiliation and type of employment, academic category, years of research and teaching experience, disciplinary areas of activity (selected from a predefined list of seven areas), and geochronological terrains of activity (selected from a predefined list of five terrains).

The second section presented the seven chrono-thematic domains. For each domain, respondents were first asked whether they had sufficient knowledge to nominate geoscientists (binary response: “I have sufficient knowledge to answer” / “I do not have sufficient knowledge to answer”). Those who answered affirmatively were invited to nominate up to ten geoscientists they considered most relevant to the development of geological knowledge in that domain, ranked in decreasing order of importance (1 = most important). No suggested lists were provided: nominations were entirely free, a design choice adopted after piloting revealed ceiling effects and framing biases in an earlier closed-list version of the instrument [26].

These seven domains correspond to those adopted in Andrade et al. [27], in the work A Geology of Portugal: Contributions of Geoeducation to Teacher Education [Uma Geologia de Portugal. Contributos da Geoeducação para a Formação de Professores]. The seven domains were: (1) Geotectonic Framework of the Iberian Peninsula and Europe; (2) Precambrian; (3) Lower Paleozoic; (4) Upper Paleozoic; (5) Mesozoic; (6) Cenozoic; and (7) Meso-Cenozoic of the Atlantic Islands. The scope of the study was delimited to geological research on mainland Portugal and the Atlantic archipelagos of the Azores and Madeira; geoscientists whose contributions concerned exclusively other regions, such as former Portuguese overseas territories in Africa and Asia, fell outside this scope and were therefore not eligible for nomination, regardless of nationality.

The division into seven chrono-thematic domains resulted from an articulation of chronostratigraphic, thematic, and practical criteria. From a chronostratigraphic standpoint, the domains follow the major divisions of geological time represented in Portuguese territory and in the Atlantic islands, as established in the international chronostratigraphic scale [28] and in the reference geological cartography of the territory [29]. From a thematic standpoint, the Geotectonic Framework was treated as an autonomous domain because it constitutes an interpretive framework that cuts across all chronostratigraphic periods; understanding the geotectonic structure of the Iberian Peninsula cannot be reduced to any specific period and involves a community of specialists with its own identity. From a practical standpoint, the Meso-Cenozoic of the Atlantic Islands was singled out from the mainland Mesozoic and Cenozoic because it corresponds to a radically distinct geological context (intraplate oceanic volcanism, absence of a Mesozoic sedimentary record on the islands) and to a community of researchers whose specialization, methods, and bibliographic references are largely independent of those of mainland specialists. The development and validation of this instrument, including two iterative cycles of piloting, is described in detail elsewhere [].

The survey was administered electronically through the LimeSurvey platform. The response period was eight weeks (April and May 2026). Participation was voluntary and anonymous at the level of individual responses.

2.2. Participants

The survey was directed at a purposive sample of 230 geoscientists affiliated with 10 Portuguese public universities. A total of 129 responses were received (response rate: 56.1%), of which 45 (19.6% of the total invited; 34.9% of the responses received) were classified as complete, with the respondent having provided at least one nomination in at least one domain and having fully completed Section 1, and 84 (36.5% of the total) as partial. Analysis of the partial responses reveals that most (n = 71; 84.5%) completed Section 1 but did not go on to provide any nomination, while 13 respondents (15.5% of the partial responses) provided at least one nomination, one of which corresponded to a non-interpretable response (the character “X”). To maintain methodological homogeneity, only the 45 complete responses were used to construct the rankings. The instrument did not prevent self-nomination; however, given the anonymous nature of the questionnaire, it is not possible to determine whether, or to what extent, this phenomenon occurred. Profile data from the partial responses are reported as a non-response analysis.

Regarding the distribution by sex, 57.8% (n = 26) of participants were male and 40.0% (n = 18) were female. One participant (2.2%) preferred not to answer. Regarding nationality, 95.6% (n = 43) of participants were Portuguese, while 4.4% (n = 2) had another nationality, corresponding to one Spanish and one Italian participant. Forty-two held a doctoral degree in geology or a related field (93.3%), and ten held a habilitation title1 (22.2%). Thirty-eight were integrated into the university teaching career (84.4%), three into the scientific research career, and four had another type of affiliation. The mean research experience was 29.2 years (SD = 11.9; range: 0-43) and the mean teaching experience was 27.8 years (SD = 14.0; range: 1-47). In terms of disciplinary areas of activity, 24 respondents (53.3%) reported activity in Environment and Society / Environmental Geology; 13 (28.9%) in External Geodynamics (Stratigraphy, Sedimentology, and Paleontology); 8 (17.8%) in Internal Geodynamics (Structural Geology, Tectonics, and Geophysics); 6 (13.3%) in Rock Materials (Geochemistry, Mineralogy, and Petrology); 4 (8.9%) in Education and History of the Geosciences; 4 (8.9%) in Geomorphology; and 17 (37.8%) in Resources, Engineering, and Energy. Respondents could select multiple areas. Table 1 presents the distribution of the 45 respondents across the ten public universities contacted, together with the response rate per institution. Note that the response rate varied substantially between institutions, from NOVA University Lisbon (39.1%) to University of Lisboa (7.8%), the latter despite being the institution with the largest number of invitees (n = 77). University of Madeira, with two invites, obtained no responses.

2.3. Data Processing: Name Normalization

Nomination lists were provided as free-text entries, resulting in substantial orthographic variation in geoscientists’ names. Three main types of variation were identified: (a) spelling variants of the same name (e.g., “Rogério Rocha”, “Rogério Bordalo da Rocha”, and “Rogério Bordalo Rocha”); (b) abbreviated or partial forms (e.g., “Zby” for “Georges Zbyszewski”, “Telles Antunes” for “Miguel Telles Antunes”); and (c) typographical or memory errors (e.g., “Berkley” for “Berkeley”, “Ruget” for “Ruget Perrot”).

Before any quantitative analysis, all names were normalized within each domain through a systematic procedure: (i) identification of all unique name strings per domain; (ii) construction of a domain-specific normalization map assigning variants to a canonical name; (iii) validation of all harmonization decisions by the principal investigator. In ambiguous cases, the most complete form documented in the Portuguese geoscientific literature was adopted. Lists with more than ten entries were truncated to the first ten. Intra-list duplicates (the same geoscientist listed twice by the same respondent) were reduced to a single entry, counting only the first occurrence.

The number of variants merged per domain ranged between 6 (Upper Paleozoic) and 23 (Mesozoic), reflecting both the greater dispersion of nominations in domains with more respondents and the more fragmented and specialized knowledge of less consensual figures, known only to a restricted subset of respondents.

2.4. Construction of the Rankings and Cut-Off Criterion for the Biographical Corpus

For each domain, the ranking was constructed by counting the total number of nominations received by each geoscientist, regardless of position on the list. Positional information (1st to 10th place) was recorded separately and is reported as complementary descriptive statistics.

The definition of the biographical corpus (the set of geoscientists for whom biographical texts will be produced) followed a uniform criterion across all domains: inclusion of all geoscientists with three or more nominations, provided this threshold coincided with a natural break in the frequency distribution immediately before a broad tie at two nominations. This criterion is methodologically defensible for the following reasons. First, the threshold of three independent nominations establishes a minimum consensus level among respondents: a geoscientist mentioned by at least 20% of respondents in each domain, in a survey with free response and no suggested list, represents a level of recognition that can hardly be attributed to chance. Second, the existence of broad ties at a frequency of two nominations would make any cut-off within that interval arbitrary, so the break before the tie is the only objectively defensible cut-off point.

In the case of the geotectonic framework, the domain with the largest number of respondents (n = 32), the threshold was raised to five or more nominations, since the threshold of three nominations represents only 9.4% of respondents (insufficient to establish consensus on such a broad base), whereas five nominations represent 15.6%, more defensible as a minimum threshold of collective recognition. In all remaining domains (n = 12-20 respondents), the threshold of three nominations was applied uniformly.

2.5. Analysis of the Qualitative Justifications for First Place

For each of the seven domains, participants who placed a geoscientist in first place were invited to indicate, in free text (maximum three lines), the scientific contributions that, in their view, justified that choice. These justifications were associated with the geoscientist actually placed in first place by each respondent (and not with the geoscientist with the highest total number of mentions in the domain, which in some cases differs, as occurs in the Cenozoic). The analysis of these justifications was qualitative and interpretive in nature, conducted by a single analyst, without a second coder or formal calculation of inter-rater agreement; the excerpts presented in Section 3.2 to Section 3.8 are illustrative of the reasons most frequently invoked for each dominant figure, and do not constitute an exhaustive coding of the entire free-text corpus. This limitation is revisited in Section 6.

3. Results

3.1. Overview

Table 2 presents the summary statistics for the seven domains. In total, the 45 respondents produced 817 nominations distributed across 220 unique geoscientist–domain pairs (after normalization). The participation rate per domain ranged from 26.7% (Upper Paleozoic, n = 12) to 71.1% (Geotectonic Framework, n = 32), reflecting the distribution of the community’s specializations. The overall average of names per list was 6.5 (SD = 2.8), with considerable variation across domains (minimum of 5.1 in the Atlantic Islands, maximum of 7.2 in the Upper Paleozoic). This variation suggests that respondents active in the more specialized domains (Upper Paleozoic) tend to have longer lists, possibly because, being a domain with a more restricted audience, the respondents who chose to answer are those with more in-depth knowledge.

The distribution of nominations is strongly asymmetric across all domains. The proportion of geoscientists nominated only once ranged from 32.5% (Mesozoic: 13 of 40 names) to 63.5% (Lower Paleozoic: 33 of 52 names). This asymmetry is characteristic of collective recognition processes: a small core of figures concentrates most nominations, while a long tail of names reflects more idiosyncratic knowledge specific to sub-networks of the community.

Table 3 presents the concentration of nominations within the biographical corpus and among the three most-nominated geoscientists in each domain.

The degree of concentration within the biographical corpus is notably higher in the Mesozoic (77.0%), the Cenozoic (60.4%), and the Atlantic Islands (63.6%) than in the Paleozoic and Precambrian geochronological terrains (~47-55%), reflecting the community’s greater consensus on which figures are central to the sedimentary and volcanological segments.

3.2. Geotectonic Framework of the Iberian Peninsula and Europe

3.2.1. Descriptive Statistics

The domain with the highest participation was the Geotectonic Framework, with 32 respondents (71.1% of the total), who produced 222 mentions distributed across 84 unique geoscientists (after normalization). The average number of names per list was 6.9 (SD = 2.9; minimum = 1; maximum = 10), indicating that most respondents did not exhaust the limit of ten names. The distribution of nominations by position shows a progressively decreasing trend: the 1st position was filled by 32 respondents (100%), the 5th by 25 (78.1%), and the 10th by only 10 (31.2%). Forty-seven of the 84 identified geoscientists (56.0%) received a single nomination; 15 (17.9%) received two; and 22 (26.2%) received three or more.

The biographical corpus of the Geotectonic domain includes the 12 geoscientists with five or more nominations, who absorb 108 of the 222 total mentions (48.6%). The five-nomination cut-off (rather than three, as in the other geochronological terrains) results from the fact that this is the domain with the largest number of respondents: with 32 participants, the three-nomination threshold represents only 9.4% of respondents, while five nominations represent 15.6%, a more demanding and more defensible level of consensus for a domain with a larger response base.

3.2.2. Ranking

Table 4 presents the complete ranking of the twelve geoscientists in the biographical corpus of the Geotectonic Framework, ordered by total number of nominations, with the percentage of respondents who nominated them and the distribution across the first three positions (P1, P2, P3).

António Ribeiro stands out even more unambiguously than initially expected as the most recognized figure in this domain, with 28 nominations (87.5% of respondents) and 16 first-place rankings: the highest value in any position across the entire survey. Rui Dias emerges in a clear second place, with 17 nominations (53.1%), creating a dominant duo that reflects the centrality of his intellectual partnership in constructing the Iberian geotectonic framework [30]. Among the remaining geoscientists in the corpus, Carlos Ribeiro, José Ramón Martínez Catalán, and Fernando Noronha tie for third place (8 nominations each), followed by Nery Delgado (7), by Paul Choffat and José Tomás Oliveira (6 each), and by a broad group of four geoscientists tied with 5 nominations each (Manuel Julivert, Carlos Teixeira, António Mateus, and José Carlos Kullberg). Also notable is the presence of Carlos Ribeiro, Nery Delgado, and Manuel Julivert, figures from the 19th and early 20th centuries, in the biographical corpus, indicating that the community retains memory of the founding contributions to this area.

3.2.3. Qualitative Justification for First Place

Of the 16 respondents who placed António Ribeiro in first place in this domain, 9 (56.3%) provided a free-text justification. The justifications converge consistently on his contribution to geodynamics and plate tectonics in the Iberian Peninsula, with recurring mentions of the “geodynamic model for the Iberian Peninsula”, of “knowledge of Variscan tectonics”, and of the creation of scientific infrastructure (“created the Laboratory of Tectonophysics and Experimental Tectonics in 1992”). One respondent attributed recognition to him ex aequo with Rui Dias, for the “geotectonic models and the 2 published volumes of Geology of Portugal”.

3.3. Precambrian

3.3.1. Descriptive Statistics

The Precambrian domain had 15 respondents (33.3%), who produced 91 mentions distributed across 46 unique geoscientists. The average number of names per list was 6.1 (SD = 3.1; minimum = 1; maximum = 10). The distribution by position reveals a sharper drop from the 5th position onward (9 nominations vs. 15 in the first three), which may indicate that specific knowledge about Precambrian figures is more limited and more concentrated in the top positions. Twenty-six of the 46 geoscientists (56.5%) received a single nomination, reflecting the specialized nature of this domain and the greater dispersion of knowledge about its figures. The biographical corpus includes the 9 geoscientists with three or more nominations, who absorb 43 of the 91 mentions (47.3%).

3.3.2. Ranking

Table 5 presents the complete ranking of the nine geoscientists in the biographical corpus of the Precambrian, ordered by total number of nominations, with the percentage of respondents who nominated them and the distribution across the first three positions (P1, P2, P3).

In the Precambrian, António Ribeiro maintains a clear lead (10 nominations; 66.7%), with a profile similar to that of the Geotectonic domain: he is predominantly nominated in 1st place (4 first-place rankings out of 10 nominations). Carlos Teixeira, Rui Dias, and Francisco Gonçalves tie for 2nd place (5 nominations each). Nery Delgado, a foundational figure of 19th-century Portuguese geology, appears in 5th place, tied with Manuel Bernardo de Sousa and Fernando Noronha (4 nominations each), evidencing a marked historical awareness among Precambrian specialists.

3.3.3. Qualitative Justification for First Place

Of António Ribeiro’s 4 first-place nominations in this domain, 2 included a justification, referring to his “comprehensive geological vision of Portuguese geology” and to his “fundamental contribution to understanding the Variscan Orogeny in Portugal,” reinforcing the cross-domain pattern already identified in the Geotectonic Framework (Section 3.2.3).

3.4. Lower Paleozoic

3.4.1. Descriptive Statistics

The Lower Paleozoic had 16 respondents (35.6%), who produced 104 mentions distributed across 52 unique geoscientists. The average number of names per list was 6.5 (SD = 2.5; minimum = 2; maximum = 10). The distribution by position is relatively uniform up to the 4th position (14-16 nominations), with a sharper drop from the 7th onward. Thirty-three of the 52 geoscientists (63.5%) received a single nomination; 7 (13.5%) received two; and 12 (23.1%) received three or more, forming the biographical corpus of 12 geoscientists (57 of 104 mentions; 54.8%).

3.4.2. Ranking

Table 6 presents the complete ranking of the twelve geoscientists in the biographical corpus of the Lower Paleozoic, ordered by total number of nominations, with the percentage of respondents who nominated them and the distribution across the first three positions (P1, P2, P3).

The Lower Paleozoic domain has the distinctive feature of two geoscientists tied for 1st place: Nery Delgado and António Ribeiro, both with 8 nominations (50.0%). This result is notable: Nery Delgado, a 19th-century researcher, stands on equal footing with António Ribeiro, the most recognized contemporary geoscientist, and is the one placed in first position more often by respondents (6 first-place rankings, versus 3 for António Ribeiro). The explanation likely lies in the fact that Nery Delgado produced pioneering work precisely on the Portuguese Lower Paleozoic, becoming an unavoidable reference for specialists in this period. Rui Dias and José Tomás Oliveira follow, tied for 3rd place (6 nominations each). Carlos Teixeira, Carrington da Costa, Fernando Noronha, José Manuel Piçarra, and Artur Sá complete the core of the corpus (4 nominations each), while Ícaro Dias da Silva, Carlos Ribeiro, and Paul Choffat, other historical figures, close the biographical corpus, confirming that the memory of the Lower Paleozoic in Portugal retains a more pronounced historical dimension than other geochronological terrains.

3.4.3. Qualitative Justification for First Place

Considering specifically the first-place rankings assigned by each respondent (rather than the total number of mentions), Nery Delgado is the geoscientist most often placed in 1st place in this domain (6 first-place rankings), ahead of António Ribeiro (3 first-place rankings). Of Nery Delgado’s 6 first-place nominations, 5 included a justification, which contrasts with the other geochronological terrains and suggests a particularly well-articulated consensus. The justifications focus consistently on his founding role in Portuguese Paleozoic stratigraphy: he is described as having “established the stratigraphic foundations of Portuguese Paleozoic geology” and as “the greatest historical reference for the Portuguese Paleozoic”, with explicit mention of his “monumental monographs on the Silurian [...] and the Cambrian” and of his “detailed study of fossils (trilobites, graptolites)”. One respondent specified his mapping work “in Valongo and Buçaco”.

3.5. Upper Paleozoic

3.5.1. Descriptive Statistics

The Upper Paleozoic was the domain with the lowest participation: 12 respondents (26.7%), who produced 87 mentions distributed across 44 unique geoscientists. Paradoxically, this is also the domain with the highest average number of names per list (7.2; SD = 2.6; minimum = 4; maximum = 10), suggesting that those who responded have specific and in-depth knowledge. The distribution by position is notably uniform up to the 4th position (12 nominations at each), with a drop from the 5th onward. Twenty-seven of the 44 geoscientists (61.4%) received a single nomination; 9 (20.5%) received two; and 8 (18.2%) received three or more, forming the biographical corpus of 8 geoscientists (42 of 87 mentions; 48.3%).

3.5.2. Ranking

Table 7 presents the complete ranking of the eight geoscientists in the biographical corpus of the Upper Paleozoic, ordered by total number of nominations, with the percentage of respondents who nominated them and the distribution across the first three positions (P1, P2, P3).

António Ribeiro clearly leads the Upper Paleozoic, with 8 nominations (66.7%) and 6 first-place rankings, followed by José Tomás de Oliveira (7; 58.3%) and Rui Dias (6; 50.0%). Nery Delgado and Zélia Pereira tie for 4th place, with 5 nominations each (41.7%). The presence of Carlos Ribeiro and Nery Delgado (19th century) and Carlos Teixeira (20th century) in the biographical corpus confirms the historical dimension of recognition in this segment.

3.5.3. Qualitative Justification for First Place

Considering specifically the first-place rankings assigned by each respondent, António Ribeiro leads with 4 first-place rankings. Of his 4 first-place nominations, 3 included a justification, referring to his position as a “key figure in the tectonics and geodynamics of the Iberian Variscan Chain” and to his “decisive contributions to the interpretation of the Variscan Orogeny”, with one additional and more specific mention of “Upper Paleozoic stratigraphy”.

3.6. Mesozoic

3.6.1. Descriptive Statistics

The Mesozoic had 20 respondents (44.4%), who produced 135 mentions distributed across 40 unique geoscientists. The average number of names per list was 6.9 (SD = 2.7; minimum = 2; maximum = 10). The distribution by position is relatively uniform up to the 3rd position (19-20 nominations), with a progressive decrease from the 4th onward. Thirteen of the 40 geoscientists (32.5%) received a single nomination; 9 (22.5%) received two; and 18 (45.0%) received three or more. The Mesozoic has the most extensive biographical corpus of all geochronological terrains (18 geoscientists), absorbing 104 of the 135 mentions (77.0%).

3.6.2. Ranking

Table 8 presents the complete ranking of the eighteen geoscientists in the biographical corpus of the Mesozoic, the most extensive of all geochronological terrains, ordered by total number of nominations, with the percentage of respondents who nominated them and the distribution across the first three positions (P1, P2, P3).

The Mesozoic is the only domain with an unambiguous leader: Paul Choffat, with 11 nominations (55.0%) and 9 first-place rankings out of 11 nominations, a leadership profile unmatched in the survey. This result is consistent with Choffat’s historical contribution to knowledge of Portuguese Mesozoic stratigraphy, which remains a fundamental reference to this day. Ana Cristina Azerêdo emerges alone in 2nd place (9 nominations), followed by Luís Vítor Duarte, Georges Zbyszewski, and Miguel Magalhães Ramalho, tied for 3rd place (8 nominations each), representing the contemporary generation of Mesozoic stratigraphy specialists, alongside Zbyszewski’s established presence. The biographical corpus of the Mesozoic also includes international researchers – Jacques Rey, Christian Palain, and Christiane Ruget-Perrot, of the French school – whose recognition by the Portuguese community evidences the collaborative dimension of research in this segment.

3.6.3. Qualitative Justification for First Place

Of Paul Choffat’s 9 first-place nominations, 7 included a justification, the highest response rate among all geochronological terrains. The dominant and almost unanimous theme is that of Choffat as a founding figure: he is repeatedly described as the “father of Portuguese Mesozoic stratigraphy” (the expression “father” appears in two independent responses), author of “monumental work of surgical precision in the biostratigraphy and cartography of the Jurassic and Cretaceous”, who “defined most of the chronostratigraphic units [...] that are still generically valid and recognizable in the field today”. One respondent also noted his “initial contributions to mineralogy”.

3.7. Cenozoic

3.7.1. Descriptive Statistics

The Cenozoic had 16 respondents (35.6%), who produced 101 mentions distributed across 43 unique geoscientists. The average number of names per list was 6.3 (SD = 2.5; minimum = 3; maximum = 10). The distribution by position is uniform up to the 3rd position (16 nominations), with a sharper drop from the 6th onward (8 nominations). Twenty-two of the 43 geoscientists (51.2%) received a single nomination; 9 (20.9%) received two; and 12 (27.9%) received three or more, forming the biographical corpus of 12 geoscientists (61 of 101 mentions; 60.4%).

3.7.2. Ranking

Table 9 presents the complete ranking of the twelve geoscientists in the biographical corpus of the Cenozoic, ordered by total number of nominations, with the percentage of respondents who nominated them and the distribution across the first three positions (P1, P2, P3).

In the Cenozoic, João Pais leads with 10 nominations (62.5%), but with a different profile from that of Paul Choffat in the Mesozoic: only 1 first-place ranking out of 10 nominations suggests he is a widely shared reference but not systematically placed in absolute prominence. Pedro Proença Cunha appears in 2nd place (8 nominations), being particularly notable for having 5 second-place rankings; he is frequently the second name respondents write down. Miguel Telles Antunes follows in 3rd place (7 nominations). António Galopim de Carvalho, with 4 first-place rankings out of 6 nominations, has the most polarized profile at the top of the Cenozoic, tied for 4th place with Georges Zbyszewski. Georges Zbyszewski, incidentally, is the only geoscientist to appear in the biographical corpus of three distinct geochronological terrains (Mesozoic, Cenozoic, Atlantic Islands).

3.7.3. Ranking

The dissociation between aggregate recognition and first place, already noted in Section 3.7.2 regarding João Pais (only 1 first-place ranking out of 10 nominations), is directly reflected in the qualitative justifications: the geoscientist most frequently placed in first place by individual respondents is not João Pais, but rather António Galopim de Carvalho (4 first-place rankings), which well illustrates the distinction between a “community consensus” (measured by total mentions, in which João Pais leads) and an “individual preference” (measured by first-place rankings, in which Galopim de Carvalho leads). Of Galopim de Carvalho’s 4 first-place nominations, 3 included a justification, relating to his “tectono-sedimentary study of the Cenozoic, particularly in the Tagus basin,” to the creation of the “school of Sedimentology in Portugal,” and also to the “valorization of geological heritage [and] outreach of the geosciences,” a dimension of science communication absent from the justifications for the other geochronological terrains.

3.8. Meso-Cenozoic of the Atlantic Islands

3.8.1. Descriptive Statistics

The Atlantic Islands domain had 15 respondents (33.3%), who produced 78 mentions distributed across 34 unique geoscientists, the smallest number of unique geoscientists of all geochronological terrains, reflecting the more restricted universe of researchers active specifically in this context. The average number of names per list was 5.1 (SD = 2.0; minimum = 3; maximum = 10), the lowest of all geochronological terrains, suggesting that specific knowledge about the Atlantic Islands is, on average, less extensive. The distribution by position shows a very sharp drop from the 6th position onward (only 4 nominations at the 6th position vs. 15 in the first three), consistent with a domain where knowledge is concentrated in few figures. Nineteen of the 34 geoscientists (55.9%) received a single nomination; 5 (14.7%) received two; and 10 (29.4%) received three or more, forming the most concentrated biographical corpus in the survey (62.8% of total mentions).

3.8.2. Ranking

Table 10 presents the complete ranking of the ten geoscientists in the biographical corpus of the Meso-Cenozoic of the Atlantic Islands, ordered by total number of nominations, with the percentage of respondents who nominated them and the distribution across the first three positions (P1, P2, P3).

The Atlantic Islands domain shows a leadership structure with José Madeira and Victor Hugo Forjaz clearly ahead, followed by a group of five geoscientists tied with 5 nominations each (33.3%). This group includes figures from different generations: Georges Zbyszewski (20th century, a pioneer of Azorean geology), António Serralheiro and António Brum da Silveira (mid-20th-century researchers), and João Carlos Nunes and João Luís Gaspar (contemporary researchers). The distribution of first-place rankings is also revealing: Georges Zbyszewski and João Carlos Nunes each have 2 first-place rankings, while António Brum da Silveira, António Serralheiro, and João Luís Gaspar have 0, meaning they are recognized as relevant but rarely as the most relevant. Frederico Machado, with only 3 nominations but 1 first-place and 2 second-place rankings, has a more polarized recognition profile than his absolute frequency suggests.

3.8.3. Qualitative Justification for First Place

Of José Madeira’s 4 first-place nominations, only 1 included a justification. This low justification rate should be interpreted in light of two compounding factors: the specialized sub-community in island geology is itself small (as noted in Section 3.8.1), which constrains the absolute number of respondents in this domain, and the number of respondents providing justifications was correspondingly limited. Both factors likely contribute to the sparsity of qualitative data available for this domain.

4. Discussion

4.1. Cross-Domain Consensus and Canonical Figures

The most consistent result of this survey is the emergence of cross-domain consensus across all geochronological terrains assessed. António Ribeiro stands out as the most recognized figure in the Geotectonic Framework of the Iberian Peninsula and Europe, Precambrian, and Lower and Upper Paleozoic geochronological terrains (four distinct geochronological terrains), reflecting the breadth and influence of his contribution to understanding the geological structure of the Iberian Peninsula. The centrality of António Ribeiro in the community’s disciplinary memory is analogous to what Callon [31] termed an “obligatory passage point”: his work constitutes a reference that cannot be bypassed regardless of the specialization of whoever studies Iberian geology.

Paul Choffat in the Mesozoic and João Pais in the Cenozoic emerge as the dominant figures in their geochronological terrains, but with distinct profiles: Choffat with an exceptional degree of polarization (9 first-place rankings out of 11 nominations), João Pais with recognition more distributed across list positions. This difference may in part reflect the historical character of Choffat’s figure, whose work is today unequivocally recognized as foundational, versus the contemporaneity of João Pais, whose contributions, while extensive, are evaluated more variably by his peers.

Georges Zbyszewski is the only geoscientist present in the biographical corpus of three geochronological terrains (Mesozoic, Cenozoic, Atlantic Islands), reflecting the exceptional breadth of his research activity across decades. Fernando Noronha appears in the corpus of the Geotectonic, Precambrian, and Lower Paleozoic geochronological terrains, evidencing cross-domain recognition in the older geochronological terrains of the chronological sequence.

4.2. Diversity and Dispersion: The Long Tail of Nominations

A structural pattern common to all geochronological terrains is the strongly asymmetric distribution of nominations, with a long tail of geoscientists mentioned only once. This proportion, between 32.5% and 63.5% of unique geoscientists depending on the domain, is characteristic of collective recognition processes in scientific communities [32] and has a two-fold interpretation. On one hand, it indicates that the core of shared canonical references is relatively small and stable: the biographical corpus typically represents only 14-45% of the unique geoscientists identified yet absorbs 47–77% of total mentions. On the other hand, the long tail of unique names reflects the richness and diversity of respondents’ specific knowledge: each niche specialist knows and recognizes figures that most of their colleagues did not nominate.

This asymmetry has implications for interpreting the rankings. The geoscientists in the biographical corpus are not necessarily the “best” or the “most important” in an absolute sense but are those whose recognition transcends specialty subgroups and is shared by a sufficiently broad proportion of the community. Geoscientists in the long tail may have contributions equally significant within their niche, which simply were not evaluated by most respondents for reasons of specialization.

4.3. The Historical Dimension of Disciplinary Memory

One of the most notable results of the survey is the consistent presence of historical figures, such as Nery Delgado, Carlos Ribeiro, Carlos Teixeira, Paul Choffat, Berkeley Cotter, and Frederico Machado, in the biographical corpora of multiple geochronological terrains. Nery Delgado, a 19th-century researcher, appears in the corpus of the Lower Paleozoic, Upper Paleozoic, and Precambrian, leading the Lower Paleozoic in a tie with António Ribeiro. This longevity of recognition is an indicator of the historical depth of the disciplinary memory of the Portuguese geosciences and of the durability of pioneering contributions.

At the same time, the geochronological terrains that attracted the largest number of contemporary respondents – the Geotectonic Framework and the Mesozoic – show a smaller proportion of historical figures in their corpus. This pattern is consistent with the hypothesis that domains with broader, more heterogeneous participation include a smaller share of respondents with specific training or activity in the history of the geosciences, and it is precisely among these specialists that recognition of past figures tends to be more salient [7,8].

Only three female geoscientists are included in the biographical corpora of the seven geochronological terrains: Ana Cristina Azerêdo (9 nominations in the Mesozoic), Zélia Pereira (5 nominations in the Upper Paleozoic), and Christiane Ruget Perrot (3 nominations in the Mesozoic, a French researcher). These three figures represent 5.9% of the 51 unique geoscientists selected, in a corpus dominated by male researchers at a ratio of 16:1. This result reflects the historical gender structure of the Portuguese geosciences, in which women had very limited access to scientific institutions and research careers throughout the 19th and 20th centuries, and not a bias of the survey. It is, nonetheless, a finding that should be made explicit in the presentation of the biographical materials to be produced within the GeoFaces project.

4.4. The French School in the Mesozoic Corpus: Recognition Without Borders

The biographical corpus of the Mesozoic includes three non-Portuguese researchers belonging to the so-called French school of Jurassic and Cretaceous stratigraphy: Jacques Rey, Christian Palain, and Christiane Ruget-Perrot. Their presence, with 4, 4, and 3 nominations respectively, under conditions of free response and with no suggested list whatsoever, is a result that merits reflection.

First, it shows that the collective recognition of the Portuguese geoscientific community is not confined to researchers of Portuguese nationality. The Geotectonic corpus likewise includes José Ramón Martínez Catalán and Manuel Julivert, both Spanish, with 8 and 5 nominations respectively. These results reflect the inherently collaborative and transnational nature of geoscientific research: the geological knowledge of a territory is built by whoever studies it, regardless of their origin. Portuguese Mesozoic geology was developed in close collaboration with French researchers during the 1960s to 1990s, and this collaborative legacy is present in the community’s memory.

Second, the presence of these international figures raises a methodological question relevant to future studies: to what extent should rankings of geoscientists “most relevant to Portuguese geology” be understood as rankings of Portuguese geoscientists or as rankings of contributions to knowledge of Portuguese geology, regardless of the nationality of those who produced them? The data from this survey answer clearly: the Portuguese geoscientific community recognizes contributions for their value to the field, not for the origin of their author. This result is consistent with Bourdieu’s [33] sociology of the scientific field, according to which scientific capital accumulates according to contributions to knowledge and not according to the national or institutional position of those who produce it.

Third, the absence of international researchers in the corpora of the Precambrian, Paleozoic, and Cenozoic geochronological terrains, where research was more markedly developed by Portuguese geoscientists, reinforces the interpretation that the presence of foreign figures in the Mesozoic is not a methodological artifact but a faithful reflection of the history of research in this specific segment.

4.5. The Atlantic Islands: A Domain with Its Own Characteristics

The Atlantic Islands domain distinguishes itself from the others in three respects. First, it has the lowest average number of names per list (5.1), reflecting more specialized and possibly more concentrated knowledge. Second, it has a high degree of concentration of mentions within the biographical corpus (63.6%), although lower than that of the Mesozoic (77.0%, the highest of all geochronological terrains), indicating that the corpus figures are recognized by most respondents active in this domain. Third, the coexistence in the corpus of historical figures (Georges Zbyszewski, Frederico Machado) and recently active researchers (João Carlos Nunes, Ricardo Ramalho, João Mata) evidences an ongoing generational transition in the disciplinary memory of this domain, which is explored further in the inferential analysis reported in the companion article of this series.

4.6. Convergence Between Quantitative Rankings and Qualitative Justifications

The qualitative justifications associated with first place in each domain (Section 3.2.3 to Section 3.8.3) converge notably with the quantitative patterns described in Section 3.1 to Section 3.8 and Section 4.1 to Section 4.3 and reinforce them in three respects. First, the vocabulary spontaneously used by respondents to justify their choices (“father of stratigraphy”, “established the foundations”, “the greatest historical reference”, “key figure”) is systematically a vocabulary of disciplinary foundation, rather than of productivity or bibliometric impact, corroborating the interpretation advanced in Section 4.3 that the disciplinary memory of the Portuguese geosciences is organized around a small number of founding figures per domain, rather than around indicators of recent scientific output.

Second, the geochronological terrains with the greatest quantitative concentration of first-place rankings on a single geoscientist (the Mesozoic, with Paul Choffat, and the Lower Paleozoic, with Nery Delgado) are also the geochronological terrains with the highest rate of justifications provided (7 of 9, and 5 of 6, respectively) and with the most uniform discourse among different respondents, suggesting that the quantitative concentration of recognition and the qualitative articulation of that recognition vary together: the more consensual the figure, the more readily respondents can put their choice into words.

Third, the case of the Cenozoic (Section 3.7.3) demonstrates that the question used to construct the quantitative consensus rankings (total mentions received, regardless of position) and the qualitative question about the reason for the first-place choice sometimes capture distinct phenomena: João Pais leads the community’s broad consensus (more respondents consider him relevant in some position), but it is Galopim de Carvalho whom respondents most frequently choose as their personal first-place reference, and it is also to him that they attach the most developed justifications, notably linked to science communication and the valorization of geological heritage. This dissociation between “community reference” and “personal reference” constitutes an interesting counterpoint to the reading, made in Section 4.1, that consensus is always unidimensional, and suggests that the two indicators (total mentions vs. first-place rankings) capture partly distinct dimensions of disciplinary recognition.

4.7. Respondents’ Reflexivity on the Limits of the Methodology

Beyond the quantitative patterns presented, the spontaneous comments provided by 10 of the 45 respondents (22.2%) in the survey’s final question offer a complementary, and largely convergent, perspective on the limits of the methodology adopted.

A first set of comments evidences an explicit epistemic awareness, on the part of the respondents themselves, of the partial and situated nature of their knowledge of the geoscientific community. Respondent ID106 noted that “each of our views on each geoscientist is, first and foremost, limited by our professional context and by physical proximity”, adding that “even regarding visibility, my opinion is partial, as it is limited to the opinions provided to me only by the people I know directly”. In the same vein, respondent ID108 acknowledged having abstained from answering certain questions “for considering that I lack the knowledge indispensable to a fair assessment with a high degree of confidence,” and respondent ID15 noted that a prolonged training period abroad tends to dilute the national references available for nomination.

A second set of comments addresses the design of the survey itself. The most developed comment (ID100) questions the operationalization of the concept of “importance” (“Importance in what sense? There are many types of importance...”) and argues that the chronostratigraphic division introduced a structural bias by excluding researchers with activity spanning several geochronological terrains (for example, igneous petrology specialists not associated with a specific era), concluding that “the results also ended up saying more about who answered than about the reality they seek to analyze”. Respondent ID133 also noted a possible conflation, throughout the survey, between “the great figures of scientists who dedicated themselves to Geology” and “the geologists who had a great influence on our careers”, considering this overlap of criteria a source of confusion in the responses. Other comments suggested greater thematic granularity, notably an autonomous treatment for the Quaternary given its interdisciplinary specificity (ID19), and the more prominent inclusion of the practical applicability of the work as a criterion of scientific value (ID144).

Respondent ID58 noted that gender inequality in the professional recognition of women geoscientists constitutes a factor “neglected in the present survey”, an observation that reinforces the relevance of the gender analysis reported in Section 4.3 of this article.

These comments are relevant not as isolated cases, but as direct evidence, provided by the surveyed community itself, of the methodological limitations already identified in this study: the possibility of overrepresentation of close academic and institutional networks, and the sensitivity of the rankings to the chosen thematic categorization structure.

5. Conclusions

This study presents the first evidence-based systematization of the collective recognition of the geoscientists most relevant to the development of geology in Portugal, covering the Geotectonic Framework of the Iberian Peninsula and Europe and six geochronological terrains through a structured nomination survey of 45 experts. The main conclusions are as follows:

1. The geoscientific community studied here demonstrates a robust cross-domain consensus on the most relevant figures in each domain. António Ribeiro, Paul Choffat, Georges Zbyszewski, João Pais, and José Madeira emerge as canonical figures in their respective segments, confirmed by multiple indicators (number of nominations and distribution across first-place rankings).

2. The distribution of nominations is strongly asymmetric across all geochronological terrains: a small core of geoscientists (biographical corpus: 8-18 per domain) absorbs 47-77% of total mentions, while a long tail of unique names (32.5-63.5% of the geoscientists identified) reflects more idiosyncratic knowledge specific to community sub-networks.

3. The historical dimension of disciplinary memory is substantial: figures from the 19th and early 20th centuries – Nery Delgado, Carlos Ribeiro, Carlos Teixeira, Paul Choffat, Frederico Machado – appear consistently in the corpora of multiple geochronological terrains, evidencing that the community retains awareness of the founding contributions to Portuguese geology.

4. The biographical corpus defined on the basis of a minimum-relevance criterion (≥ 3 nominations, or ≥ 5 in the case of the Geotectonic Framework, given the larger number of respondents in this domain) constitutes a methodologically defensible and empirically grounded set of figures for whom the development of biographical texts within the GeoFaces project is justified by community consensus.

5. The Mesozoic presents the most extensive corpus (18 geoscientists) and also the highest degree of concentration of mentions (77.0%), standing out clearly from the Atlantic Islands (63.6%), the second-highest value; the Precambrian and the Upper Paleozoic show greater dispersion, reflecting differences in the organization of knowledge and in the breadth of the community with competence in each domain. In particular, the institutional composition of the sample is not uniform: respondents affiliated with institutions in the Lisbon region represent 33.3% of the total (n = 15), followed by Évora (17.8%), institutions in the North (17.8%), and Coimbra (15.6%). This distribution raises the question of the extent to which respondents’ choices reflect institutional proximity to the research traditions to which they are affiliated, a question that will be explored systematically in a companion article currently in preparation, dedicated to analyzing the associations between respondents’ profiles and nomination patterns (Article 2), which will cross-reference each respondent’s affiliated institution with the institutions associated with the figures they nominated. The third article of the series will be devoted to the theoretical interpretation of the results within the framework of the sociology of disciplinary memory and the history of geology in Portugal (Article 3), currently in preparation.

6. Limitations

This study presents several limitations that should be considered when interpreting the results. Comparison of the sociodemographic profile of the complete respondents (n = 45) with that of the partial respondents (n = 84 with profile data available) reveals no substantial differences in terms of sex (complete: 58% male; partial: 64%) or nationality (both > 95% Portuguese). Partial respondents show a slightly lower average number of years of research experience (26.1 vs 29.2 years) and a somewhat lower doctoral rate (83% vs 93%), suggesting that questionnaire abandonment is associated with less academic experience, but not with differences in gender or geographic origin. This pattern is consistent with the literature on non-response in online academic surveys [34].

The sensitivity analysis conducted with the 13 partial responses that included at least one nomination (12 of which corresponded to valid nominations, one case having been excluded as non-interpretable) demonstrates that the top rankings are robust to the inclusion of these responses: the leadership positions in all geochronological terrains remain unchanged. With the addition of the partial responses, the number of respondents increases between 27% and 42% per geochronological terrain, without any geoscientist from the original corpus being displaced. Some additional entries do appear in the corpora, however (between 1 and 4 geoscientists per domain), corresponding to figures who were at the borderline of the cut-off criterion with the complete responses. The sample size (N = 45) limits the statistical representativeness of the rankings, particularly in the geochronological terrains with lower participation (Upper Paleozoic: n = 12). The purposive sampling strategy may have overrepresented researchers active in academic and institutional networks, potentially underrepresenting researchers in applied or industrial contexts. A related limitation concerns the career-stage profile of respondents: mean research experience in the complete-response sample was high (29.2 years, SD = 11.9), indicating that the survey predominantly captured the perspective of senior, established researchers. Consequently, the rankings obtained may disproportionately reflect the disciplinary memory held by this generation, rather than a generationally balanced representation of the community; early-career researchers, who may have had less exposure to the discipline’s founding figures or who may recognize a different set of contemporary references, are likely underrepresented. Future studies with larger samples could examine whether generational cohorts differ systematically in their nomination patterns, which the present sample does not allow to test with adequate statistical power.

Name normalization was carried out manually and validated by the principal investigator. Operationalizing relevance as the number of independent nominations without weighting for position is a simplification: the same frequency with different position distributions may reflect distinct recognition patterns (see, e.g., the comparison between Paul Choffat in the Mesozoic and João Pais in the Cenozoic). Not all respondents followed the instruction to rank in decreasing order of importance; at least one respondent explicitly indicated having provided an unordered list, which introduces localized uncertainty in the assignment of the 1st-place position for that case. The full psychometric validation of the instrument on the complete target population is reported separately [26].

Additionally, the analysis of the qualitative justifications for first place (Section 3.2.3 to Section 3.8.3 and Section 4.6) is interpretive and illustrative in nature: it was conducted by a single analyst, without a second coder or formal verification of inter-rater agreement, and not all respondents who placed a geoscientist in first place provided a free-text justification (response rates ranged from 25% in the Meso-Cenozoic of the Islands to 100% in the Lower Paleozoic), so the excerpts presented should be read as illustrative of the most recurrent reasons, and not as a sample necessarily representative of all the motivations underlying respondents’ choices.

The spontaneous comments provided by a subset of respondents (n = 10 of 45; IDs 15, 19, 58, 100, 106, 108, 133, 144) in the survey’s final question corroborate, in the voice of the surveyed community itself, several of these limitations: notably, the explicit acknowledgment that each respondent’s perception of relevance is limited by their professional context and physical proximity to the nominated figures, and the observation that the survey’s chronostratigraphic division may have introduced a structural bias by excluding specialists with activity spanning several domains (geochronological terrains) (see Section 4.7 for detailed discussion).