Amanda Owen

Recognition and importance of amalgamated sandy meander belts in the continental rock record

Meandering fluvial channels and their meander belts are common in modern continental sedimentary basins, yet compose a minor constituent of the reported fluvial rock record. Here we document exhumed amalgamated meander belt deposits from the upper Jurassic Morrison Formation, Utah (United States). The size of the amalgamated meander belt (9000 km2) is significantly larger than any documented previously and comparable in size to those from modern sedimentary basins. We describe a representative outcrop of sandy point bar deposits that shows features considered characteristic of both braided and meandering fluvial systems. Lateral accretion sets compose <5% of the outcrop area, yet point bar morphology is clearly visible in plan view. We suggest that difficulties in the identification of sandy, amalgamated meander belt deposits indicate that they have gone largely unrecognized in the rock record. Their recognition has important implications for basin-scale reconstructions of fluvial systems and interpretation of tectonic setting.

Mood-states, recall and subjective comprehensibility of medical information in non-patient volunteers

Abstract Factors were investigated related to the comprehensibility, recall and retention of medical information, using non-patient volunteers. At the first session, subjective comprehensibility, immediate recall and the mood-states of anxiety, depression and hostility were measured. A week later recall, anxiety, depression and hostility were reassessed. In terms of percentages of idea-units recalled, immediate recall was 44% and delayed recall was 31%. Immediate (though not delayed) recall and also subjective comprehensibility were negatively correlated with both anxiety and depression as measured at the first, but not the second session, thus highlighting the primacy of immediate mood-state in influencing recall. There was no relation between subjective comprehensibility and either of the recall scores. The results imply that subjective comprehensibility and recall are relatively independent, a result apparently inconsistent with Leys model of compliance, but suggest that both can be influenced by depressed or anxious moods. Taken together with other findings, our results could support a curvilinear relation between anxiety and recall. To maximize recall and comprehensibility, at least within a certain range of anxiety levels, anxiety and depression at the time the instructions are presented should be minimized. In a clinical setting, this may be relevant to improving patient compliance.

Uranium distribution as a proxy for basin-scale fluid flow in distributive fluvial systems

We infer system-scale fluid flow in the Late Jurassic Salt Wash fluvial succession (SW USA) by plotting uranium deposit distribution against sedimentological data, using uranium distribution as a proxy for subsurface fluid flow. More than 90% of uranium deposits in the Salt Wash occur where sandstone forms 40–55% and sand-rich channel-belts form 20–50% of the succession, which coincides with changes in channel-belt connectivity and gross-scale architecture. The paucity of uranium below these cut-off values suggests that fluid flow is related directly to predictable downstream fining and facies variations in distributive fluvial systems. Supplementary material: A summary table of location data, key trends and the amalgamation ratio method is available at https://doi.org/10.6084/m9.figshare.c.2849581.

Grand Challenges (and Great Opportunities) in Sedimentology, Stratigraphy, and Diagenesis Research

NERC Yorkshire Integrated Catchment Solutions Programme [NE/P011160/1]; NERC National Capability project Climate Linked Atlantic Sector Science Programme (CLASS)