Anders Ahlberg

Triassic-Jurassic weathering and clay mineral dispersal in basement areas and sedimentary basins of southern Sweden

Abstract The basement rocks of southern Sweden were deeply weathered in Late Triassic through Cretaceous times, and possibly even earlier. Sub-Mesozoic saprolites formed, presumably due to long-term warmth and humidity, in conjunction with decomposition of abundant organic matter and subsequent infiltration of acidic water. The upper parts of the weathering profiles were subjected to intense leaching and kaolinitisation whereas the less evolved deep weathering front is enriched in smectite. Thus, any erosion prior to full regolith development, or extraordinary deep erosion, released less developed, smectite-rich weathering material to the Late Triassic–Jurassic receiving basins. Mesozoic sedimentary successions in Southern Sweden show high detrital smectite and/or kaolinite contents, moderate illite contents and low chlorite contents, compatible with expected mid-latitude warm equable greenhouse conditions. Norian and older Triassic haematite-cemented continental arkoses and smectite-dominated clays (smectite≫kaolinite) were clearly formed in arid settings. From the Rhaetian and throughout the Jurassic, humid onshore conditions sustained abundant plant and peat accumulation, early diagenetic meteoric flushing, and intense chemical weathering. Kaolinite is therefore a dominating detrital clay mineral in these sedimentary successions (kaolinite≈illite≫chlorite and smectite (I/S)). Minor quantitative variations in clay mineralogy within the “humid climate” Rhaetian–Jurassic sedimentary successions are difficult to interpret. In deltaic coal-bearing successions, the detrital clay mineral composition is conspicuously constant (kaolinite≈illite≫chlorite), possibly due to post-depositional clay mineral transformation. Conversely, in shallow marine deposits, some quantitative variation is notable (kaolinite≈illite>variable smectite≫chlorite). This may reflect that the original detrital composition was better preserved in shallow marine settings. Smectitic clay minerals associated with gypsum and caliche nodules ambiguously indicate increased aridity towards the end of the Jurassic.

Palynostratigraphy of dinosaur footprint-bearing deposits from the Triassic–Jurassic boundary interval of Sweden

The Triassic–Jurassic boundary (c. 200 Ma) marks one of the five largest Phanerozoic mass extinction events and is characterized by a major turnover in biotas. A palynological study of sedimentary rock slabs bearing dinosaur footprints from Rhaeto–Hettangian strata of Skåne, Sweden was carried out. The theropod dinosaur footprints (Kayentapus soltykovensis) derive from the southern part of the abandoned Vallåkra quarry (Höganäs Formation) and were originally dated as earliest Jurassic (Hettangian) based on lithostratigraphy. Our results reveal that two of the footprints are correlative with the latest Triassic (latest Rhaetian) disaster zone typified by a high abundance of the enigmatic gymnosperm pollen Ricciisporites tuberculatus and Perinopollenites elatoides together with the key taxon Limbosporites lundbladii and fern spores. Two footprints are dated to correlate with the Transitional Spore-spike Interval. One footprint is interpreted as Hettangian in age based on the relatively high abundance of Pinuspollenites spp. together with the presence of the key taxa Retitriletes semimuris and Zebrasporites intercriptus. Our new palynological study suggests that the Kayentapus ichnogenus already appeared in the end of Triassic, and our study highlights the use of palynology as a powerful tool to date historical collections of fossils in museums, universities and elsewhere. The Hettangian footprint reflects a marine influence while all other studied ichnofossil specimens occur in non-marine (floodplain and delta interdistributary) sediments. The sediments associated with the Hettangian footprint include a significant proportion of charcoal transported from land after wildfires. The Rhaeto–Hettangian vegetation was otherwise characterized by multi-storey gymnosperm–pteridophyte communities.

Teaching and Learning in Hard Science Research Environments: Views of Academics and Educational Developers.

Obligatory educational training of Swedish university teachers rarely involves senior teaching staff from research‐dominated environments, despite the positive effects of junior staff training. Senior science academics were surveyed to gauge their views on the principles of teaching and learning and of teaching rewards. These views were compared with educational developers’ views on ‘ideal values of academics’ and on educational rewards. Based on this study, it is suggested that to reduce inherent teaching–research conflicts, convergence of teaching and research, in terms of teaching design and curriculum content, is necessary. To involve and convince science researchers who teach, educational staff development should probably focus on didactic aspects of their scientific disciplines and rely largely on empirical evidence.

Enigmatic late Cretaceous high palaeo-latitude lonestones in Chukotka, northeasternmost Asia

Abstract Well-rounded cobbles were encountered within a low-energy restricted marine organic-rich deposit of latest Cretaceous age in Chukotka, NE Asia. The clasts are hydrodynamically incompatible with the inferred quiet depositional environment of the host sediment. Driftwood capable of tree-rafting, glacial striations, gastrolith clast clustering, and disrupting clast impact impressions typical of volcanic ejecta were absent, as were signs of traction currents. If indeed ice-rafting is responsible, this supports recent climate models and palaeobotanical data which favour seasonal marine ice cover of high northern latitudes over a wide span of boundary conditions.

Petroleum assessment of the Mesozoic succession in the Höllviken Graben and on the Skurup Platform, southern Sweden

Abstract Investigations of the subsurface Mesozoic succession of SW Skåne, southern Sweden, have from the 1940s and onwards yielded a substantial amount of data and drill cores, but no hydrocarbons. Herein, previous data are compiled and new analyses and interpretations have been added, to explain the deficiency. This is essential as speculative exploration with little geological basis tends to recur in Skåne. The subsurface of SW Skåne comprises Rhaetian to Cenomanian sandstone units with acceptable reservoir qualities, as well as potential seals. Unpublished analyses from the 1970s also indicate promising source rock conditions. Conversely, our study shows that potential Mesozoic source rocks are few, thin, low in kerogen, and primarily gas prone. Furthermore, the kerogen is thermally immature to marginally mature, due to moderate burial. Heat flux, due to Middle Jurassic tectonic and volcanic activity, is discussed as a possibility for enhanced hydrocarbon maturation in the study area, whereas external hydrocarbon influx is considered unlikely because of the structural development of the Tornquist Zone, and the pre-Mesozoic postmature state of the Palaeozoic organicrich sediments in Skåne.

Monitoring and stimulating development of integrated professional skills in university study programmes

Abstract In Swedish higher education, quality assurance mainly focuses on course module outcomes. With this in mind we developed a qualitative method to monitor and stimulate progression of learning in two modularized engineering study programmes. A set of core professional values and skills were triangulated through interviews with students, teachers, alumni and industrial employers and aligned with national intended learning outcomes, thus defining the aims of progression. Student teams (pre-university, first, third, and fourth & fifth year) were observed addressing real industrial cases/problems of key relevance to these programme objectives. We report on observed progression and hurdles in developing approaches to industrial problem-solving; appropriate use of technical and scientific language; knowledge of chemistry, biochemistry and engineering; statistical reasoning; knowledge of economic consequences; team behaviour; project documentation; and understanding of professional ethics and risk. Our results demonstrate student progression in most areas, but also a shift in ethical focus from protecting the public towards protecting corporate interests.

Summative quality assurance systems: not good enough for quality enhancement

Abstract: In this chapter we scrutinise an elaborate institutional quality assurance model, with aspirations to develop a quality culture which aims to improve student learning, in order to discuss general issues of teaching and learning evaluation strategies. Our analysis suggests that summative student evaluations are useful for institutional quality assurance and quality enhancement at study programme level. However, they appear less efficient for quality enhancement at course module or subject discipline level, that is the loci of teaching and learning. To support quality enhancement of teaching and learning, iterative formative evaluation has greater potential and in order to promote an institutional quality culture, summative as well as formative student evaluations need to be in place, discussed, accepted and understood by all legitimate stakeholders (i.e. students, university teachers and institutional representatives).

Late Jurassic clay mineral suites of the annero Formation, southern Sweden

Abstract Two Late Jurassic successions from western Skåne were investigated with respect to clay mineral contents of mudstones. Although these resemble clay mineral suites from a third succession in Central Skåne, it is evident that different depositional areas show separate clay mineral trends with time, probably due to that detrital clay minerals were derived locally from heterogeneous weathered crystalline basement (smectite and kaolinite dominated) and from reworking of Palaeozoic shales (illite and chlorite dominated). Kaolinite is enriched in silty and sandy strata, probably due to sedimentary sorting processes and authigenic precipitation.

Sediment network meeting 1997

Shallow burial, high‐temperature diagenesis in a Lower Jurassic sandstone Mixed carbonate‐siliciclastic ramp settings in the Late Wenlock of western Gotland ‐ Slite and Mulde Beds transitional succession High‐frequency cyclicity in Silurian storm deposits Architecture and deposits of deep water wedges in the Central Tertiary Basin, Svalbard Depositional model of ice‐marginal submarine fan and delta complexes, Swedish West Coast Events and episodes in Upper Silurian reef complexes on Gotland, Sweden Markov chain analysis of clastic and authigenic microstratigraphy from the Landsort Deep in the Baltic Sea Isotope 13C enrichment in Upper Silurian (Whitcliffian) marine strata of Scania, Sweden

Contact metamorphism of Palaeozoic shale in southern Sweden: influences on clay mineralogy and implications for railway construction material properties

Abstract Abundant shale fragments were observed in dolerite material used for railway construction in western Skåne, due to quarrying of Permo-Carboniferous dolerite in contact with Silurian shale (the Colonus Shale) in the Rönnarp Quarry, western Skåne. Shale fragments were particularly enriched in the finest fractions of the crushed rock material. We analysed the clay mineralogy of shale from the railway material and at different distances from the dolerite in the quarry, in order to better understand the properties of the delivered rock material. The illite and chlorite dominated Colonus Shale in Skåne typically shows background illite crystallinity in the uppermost diagenetic realm. In the Rönnarp Quarry, fissile shale a few meters away from the dolerite intrusion shows illite crystallinity in the anchimetamorphic stage. In massive shale less than 1 m from the shale-dolerite contact, swelling clay minerals have formed at the expense of illite. Therefore, despite the massive appearance of the contact metamorphosed shale, it is suggested that such rocks should be avoided during construction material production. A tentative model for post-intrusion hydrothermal clay mineral transformation is suggested.