文章基本信息

标题：Assessing sampling of the fossil record in a geographically and stratigraphically constrained dataset: the Chalk Group of Hampshire, southern UK
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作者：Fiona M. Walker ; Alexander M. Dunhill ; Mark A. Woods 等
期刊名称：Journal of the Geological Society
印刷版ISSN：0016-7649
电子版ISSN：2041-479X
出版年度：2017
卷号：174
期号：3
页码：509-521
DOI：10.1144/jgs2016-093
语种：English
出版社：Geological Society Publishing House
摘要：Taphonomic, geological and sampling processes have been cited as biasing richness measurements in the fossil record, and sampling proxies have been widely used to assess this. However, the link between sampling and taxonomic richness is poorly understood, and there has been much debate on the equivalence and relevance of proxies. We approach this question by combining both historical and novel data: a historical fossil occurrence dataset with uniquely high spatial resolution from the Upper Cretaceous Chalk Group of Hampshire, UK, and a newly compiled 3D geological model that maps subsurface extent. The geological model provides rock volumes, and these are compared with exposure and outcrop area, sampling proxies that have often been conflated in previous studies. The extent to which exposure area (true rock availability) has changed over research time is also tested. We find a trend of low Cenomanian to high Turonian to Campanian raw richness, which correlates with, and is possibly driven by, the number of specimens found. After sampling standardization, an unexpected mid-Turonian peak diversity is recovered, and sampling-standardized genus richness is best predicted by rock volume, suggesting a species–area (or ‘genus–area’) effect. Additionally, total exposure area has changed over time, but relative exposure remains the same.