@misc{10481/61751,
year = {2020},
month = {3},
url = {http://hdl.handle.net/10481/61751},
abstract = {During the greenhouse conditions prevailing in the early–middle Eocene, larger benthic
foraminifers (LBF) spread out on carbonate platforms worldwide while rhodolith beds were scarcely
represented. This reduction in rhodolith beds coincided with a relative decrease in coralline algal
diversity and with a drastic decline of coral reef abundance. Middle Eocene rhodoliths from two
tropical (San Jacinto Fold Belt in northern Colombia and Bahoruco Peninsula in the Dominican
Republic) and two mid-latitude (Salinas Menores Ravine and Sierra del Zacatín in Southern Spain)
localities were studied. Rhodolith rudstones in the tropical areas accumulated on relatively deep
(several tens of meters) platform environments and were also redeposited in deeper settings downslope.
In Salinas Menores, rhodoliths are dispersed in planktic foraminifer-rich marls. Miliolids are common
in the infilling of constructional voids in these rhodoliths, indicating that they originally grew in
shallow-water inner-shelf settings and afterwards they were transported to deeper environments.
In Sierra del Zacatín, rhodoliths are scarce and coralline algae mainly occur as crusts attached to
and intergrowing with corals. Here, LBF dominated shallow-water carbonate platforms. In terms
of taxonomic composition, coralline algae of the order Hapalidiales are the most abundant in the
study areas, followed by Sporolithales. The order Corallinales is poorly represented except in Salinas
Menores, where it is relatively abundant and diverse. The impact of high temperatures due to high
levels of atmospheric CO2 during the Eocene and widespread oligotrophic conditions, which favored
formation of LBF-rich lithofacies, might account for the low abundance of rhodolith beds at mid and
high latitudes. In contrast, the more productive equatorial regions would have favored the formation
of rhodolith beds.},
organization = {This research was funded by Research Group RNM-190 of the Junta de Andalucía (JA and JCB),
MINECO/FEDER-UE project CGL2015-65404-R and by the Consolidated Research Group IT930-16 of the Basque
Government (VP and XOE).},
publisher = {MDPI},
keywords = {Calcareous red algae},
keywords = {Larger foraminifer lithofacies},
keywords = {Southern Spain},
keywords = {Dominican Republic},
title = {Middle Eocene Rhodoliths from Tropical and Mid-Latitude Regions},
doi = {10.3390/d12030117},
author = {Aguirre Rodríguez, Julio and Braga Alarcón, Juan Carlos},
}