SOLICITED - Female Earth-scientists have existed in the 19th century and the first half of the 20th century, in a number exceeding what we generally imagine. The causes of this oblivion about their work, their personalities, and the obstacles they met to pursue their studies and research, could enlighten the persisting unequal gender balance in Earth sciences and the struggles of female geoscientists today. In the same way many past female artists are since a few years rediscovered, scientists women tend to be more and more taken out of the dustbin of History. This huge task is already undertaken by a few persons. Before giving the main results of the review of their research, as well as some fresh contribution to this collective work in progress, the method will be detailed, as this particular subject needs some specific attentions, e.g. the consultation of not only scientific literature, but also of popularization blogs; the use of each name found to look for potential others (coauthors, teachers, students). Finally when confronted to an apparent vacuum, i.e. a geographical area or a geoscience subject counting apparently no female scientists before the 1930's, we should look deeper into it. Indeed as is well known in Earth sciences, « absence of evidence is not evidence of absence ». Common mechanisms that have first made these women work a challenge, and then hidden their figures, are discrimination, including difficult access to university and academic positions, and the attribution of their own work to men they worked with or for. They found several ways to overcome these difficulties: thanks to the support of their parents, or to the more ambiguous support of husbands or academic male mentors, through celibacy, and through team work with and/or mentorship by other women.

Presented at the European Geosciences Union General Assembly 2019 I have since then learned that the picture of Marguerite Thomas Williams is not the right one (see https://trowelblazers.com/marguerite-thomas-williams/).