Rute Coimbra

• PhD
• Assistant Professor at University of Aveiro

New evidence on the timing of early angiosperm evolution is presented through the discovery of four well-dated tricolpate pollen grains from the Early Cretaceous midlatitudes. Recovered from nearshore marine sediments in the Lusitanian Basin of Portugal, these fossils significantly expand the pre-Aptian tricolpate pollen record and document a great...

Two Kimmeridgian shallow-marine carbonate successions (mid-shelf), sharing a similar paleoclimatic framework (climatic zone), were previously explored using carbonate chemostratigraphy. Before, the goal was to detect signals related to paleoplatform bottom physiography, degree of connection with oceanic waters and overall circulation patterns. In t...

The timing of the origin of angiosperms is a long-standing topic of debate in plant evolution. Different disciplines and approaches provide highly variable age estimates. It is generally accepted, that early macro-and mesofossils showing unequivocal angiosperm features occur in lower Ap-tian deposits. Workers employing palynology, i.e., the extreme...

The accurate identification of dinosaur egg accumulations as nests or clutches is crucial for understanding the reproductive behaviour of these extinct species. However, existing methods often rely on the presence of complete eggs and embryo remains, and sedimentological criteria that are only applicable to well-structured sediments. In this study,...

The timing of the origins of angiosperms is a long-standing topic of debate in plant evolution. Different disciplines and approaches provide highly variable age estimates. It is generally accepted, that early macro- and mesofossils showing unequivocal angiosperm features occur in lower Aptian deposits. The oldest widely accepted fossilized flowers...

X-Ray Diffraction mineralogical analysis of geological sequences is a well-established procedure in both academia and industry, rendering a large volume of data in short-analytical time. Yet, standard data treatment and resulting interpretations present limitations related to the inherent complexities of natural geological materials (e.g., composit...

Found in the Upper Jurassic outcrops of Lourinhã, Portugal, and first published in 1997, the Paimogo dinosaur egg clutch is one of Portugal’s most remarkable fossils, with over one hundred eggs preserved in association with embryonic bones, of the allosauroid theropod Lourinhanosaurus. However, many questions about it have remained unanswered, even...

The qualitative and quantitative investigation of non-carbonate minerals—such as clay minerals—in ancient limestones and dolostones is a widely applied tool in palaeoenvironmental analysis. In order to exploit clay minerals as palaeoenvironmental proxies, these must be extracted from their host carbonate prior to analysis. Over the last decades, ef...

Sclerochronology makes use of (fossil) shell-archives to establish records allowing for investigation of high-resolution environmental dynamics. Nevertheless, this potential can often not be fully exploited due to the interplay between paleoenvironmental variability, vital effects and the potential diagenetic modification of skeletal materials, whi...

Shallow-platform settings with marked differences in paleoplatform bottom physiography influence the degree of connection with oceanic waters and overall circulation patterns, even when sharing the same palaeoclimatic conditions. Two Kimmeridgian shallow-marine settings have been explored to test the sensitivity and reliability of carbonate chemost...

Ephemeral carbonate facies presenting restricted geographical and temporal occurrence hold the key to complete the knowledge of past environmental conditions. Far from representing environments widespread throughout the geological history, ephemeral lithofacies embody equally relevant but more unusual scenarios. This is the case of the lumpy limest...

This study aims to evaluate the sedimentary dynamics of the Mondego River at Coimbra, a fluvial reach in which anthropogenic influence is relevant. This is expressed by an increasing urban occupation of the alluvial plain and by human-induced modifications to the channel: mainly the creation of a local base level, trapping bedload and requiring rep...

Shallow-water Cretaceous, carbonate platform archives have only rarely been explored through their elemental signature. Yet, facies-sensitive geochemical records can shed light onto the specific dynamics of shallow/proximal settings, where changes in depositional conditions are pronounced. Changes stemming from early and later diagenetic processes...

Disentangling shallow-water bulk carbonate carbon isotope archives into primary and diagenetic components is a notoriously difficult task and even diagenetically screened records often provide chemostratigraphic patterns that significantly differ from global signals. This is mainly caused by the polygenetic nature of shallow-water carbonate substra...

The elemental geochemistry of ancient shallow-marine carbonates represents an often underexplored archive of paleoenvironmental change and diagenetic pathways. Complex multi-parameter datasets from a lithologically heterogeneous sedimentary succession in the southern part of the Lusitanian Basin (Ericeira, Portugal) are presented and interpreted. T...

Deeper knowledge on dust suspension processes along semiarid zones is critical for understanding potential impacts on human health. Hermosillo city, located in the heart of the Sonoran Desert was chosen to evaluate such impacts. A one-year survey of Total Suspended Particulate Matter (TSPM) was conducted at two different heights (pedestrian and roo...

Chemostratigraphy applied to ancient marine carbonates commonly is based on one-dimensional (stratigraphic) sections or core data. As demonstrated from modern oceans, this approach underestimates the spatial complexity of physico-chemical seawater properties. Here, a several-hundred-kilometer long transect consisting of seven Upper Jurassic section...

Elemental concentrations in Phanerozoic seawater are known to fluctuate both in time and space. With regard to carbonates precipitated from marine fluids, elemental concentrations in the carbonate crystal lattice are affected by a complex array of equilibrium and non-equilibrium as well as post-depositional alteration processes. In order to assess...

Terra Nova, 24, 437–445, 2012 Abstract The notion that diagenetic imprint on ancient carbonates significantly compromises palaeoenvironmental interpretations is revealed as an oversimplification. The enigmatic case at the core of this research is an extended, homogeneous, macrofossil‐poor deposit showing distinctive dark brown colour and very fine...

The reconstruction of paleoenvironmental conditions is based on the study of ancient rock materials. For this purpose, skeletal materials are often assumed to have higher preservation potential, sometimes favored over the use of matrix micrite. However, factors such as ecology, depositional setting, mineralogy and diagenetic processes may obscure o...

Three sections from the eastern Iberian Chain are compared in terms of their geochemical signature. Stable isotope (C or O) and trace elements analysis (Mg, Sr, Fe and Mn) are complemented by cathodoluminiscence inspection and overall skeletal abundance. The goal is to approach the identification of potential sources for sedimentary contribution on...

Ice Rafted Debris (IRD) layers are widely distributed along the Northern Atlantic, representing the discharge of detrital material transported by icebergs released from the major continental ice caps during the Heinrich events (Heinrich et al. 1988, Bond et al. 1992). They provide key information on climatically forced events and are commonly used...

Matrix micrites are a commonly used carbonate archive for the reconstruction of past environmental parameters, but one that is submitted to known limitations. Main reasons for the often ambiguous value of many micrite-based isotope data sets are the unknown origin of the micrite components and their poorly resolved diagenetic history. Here we prese...

Three Ammonitico Rosso (AR) sections from the Betic Cordillera in SE Spain were analysed to obtain stable isotope records and access paleoenvironmental information. The study area corresponded to a Late Jurassic distal epioceanic setting and is characterized by the occurrence of more or less calcareous AR horizons ranging from greyish to redish col...

Abyssal marine environments combine the ideal conditions for recording the climatic instability occurred during the last glacial period. However, on a more dynamic zone, such as the Galicia Bank slope, the turbiditic activity may compromise the fidelity of a given record. In this context, we will show how very detailed magnetic measurements make po...