Topographic monitoring of a middle estuary mudflat, Humber estuary, UK – Anthropogenic impacts and natural variation

Annual topographic surveys were carried out at the Saltend mudflat (Humber estuary, UK) between 1998 and 2006. These surveys formed part of an ongoing monitoring programme to examine the potential effects on the mudflat topography of the construction and operation of a waste water treatment works (WwTW) development by Yorkshire Water. Of particular concern was the potential disruption to the sedimentological regime within the special protection area (SPA) and candidate special area of conservation (cSAC) which could affect the invertebrate communities and ornithological functioning of the site. In addition to the development of the WwTW located to the extreme north-west of the site, a port extension removing 10 ha of the Saltend intertidal mudflat (outside the SPA but immediately south east of the WwTW) also occurred between 1999 and 2006. Minimal change was noted across the site following the construction and operation of the WwTW between 1998 and 2000. However, the construction of the bund in closer proximity to the SPA and cSAC masked any potential impact the WwTW could have had across the site after 2000. Profiles and contour mapping indicate that significant mudflat accretion occurred in the immediate area of the bund, with a general increase recorded across the western section of the site since 2000. In contrast the alternations to channel planform and subsequent rapid accretion of the mudflat to the east of the jetty, being a significant distance from the developments, are attributed to natural cyclical changes.     

Data quality in applied geochemistry: the requirements, and how to achieve them

To obtain a reliable interpretation of geochemical data, we need to ensure that the measurements are of sufficiently high quality. To do this we need to be able to specify quantitatively the data quality that we need, and then to be certain that we are getting it. The latter can be achieved only if properly validated analytical methods are employed, and well-designed quality control schemes are used as a matter of routine.     

One-atmosphere melting behaviour and nomenclature of terrestrial lavas

On a plot of MgO against one-atmosphere liquidus almost all published data for lavas delineate a single trend, which is fairly well-defined above 1160° C. Segments of this trend form a convenient set of major classificatory subdivisions of lavas. It appears to be hard to justify the use of the term basalt for lavas with less than 6 percent MgO. Even with this restriction, basaltic aphanites occupy a substantial thermal (1150 to 1250° C one-atmosphere liquidi) and chemical (e.g. 6 to 11 percent MgO) range, which might profitably be subdivided. Finally, it is shown that the one-atmosphere liquidus thermal range occupied by the strongly alkalic sodic and potassic lavas is as wide as that covered by the entire set of basaltic volcanic suites from picrites and ankaramites to rhyolites, trachytes and phonolites.Presented at the symposium Recent Advances in the Studies of Rocks and Minerals at High Pressures and Temperatures held in Montreal, 1972. Jointly sponsored by the International Mineralogical Association and the Commission on Experimental Petrology.