Palynological, organic-petrographical and organic-geochemical investigations on coals and sediments of the Duckmantian, Ruhr Basin, Germany Von der Fakultät für Georessourcen und Materialtechnik der Rheinisch -Westfälischen Technischen Hochschule Aachen zur Erlangung des akademischen Grades eines Doktors der Naturwissenschaften genehmigte Dissertation vorgelegt von Dipl.-Geol. Kai Jasper aus Minden (Westfalen) Berichter: Univ.-Prof. Dr. rer. nat. Ralf Littke Univ.-Prof. (i.R.) Dr. phil. Gerd Flajs Tag der mündlichen Prüfung: 22. Dezember 2009 Diese Dissertation ist auf den Internetseiten der Hochschulbibliothek online verfügbar This thesis is dedicated to my parents, who sponsored my studies over many years and enabled me to finish this work and to Rahel, whom I love. Acknowledgements First of all I wish to thank my supervisors Prof. Dr. G. Flajs and Prof. Dr. R. Littke for proposing this project to me, for their support, and for the opportunity to complete my thesis. I would also like to express my gratitude to them for their technical and financial support and many discussions on a vast number of disciplines. In addition, I gratefully thank C. Hartkopf-Fröder from the Geological Survey of NRW, who was one of the primary proponents of this work and co-supervisor of my thesis, for his constructive discussions and feedbacks, technical support, innovative ideas and many other things, which helped me to finish this work. Furthermore, I thank Dr. Bernd Krooss for his support on chapter 2 and Prof. Dr. Jan Schwarzbauer for his discussion on chapter 4. I also thank Dr. Duncan McLean for many discussions on Pennsylvanian miospore taxonomy as well as PhD. Chris Cleal and PhD. William DiMichele for many constructive comments on chapter 3. Chapter 3 of this thesis is a contribution to IGCP 469: Late Variscan terrestrial biotas and palaeoenvironments. For the preparation of high-quality polished sections for maceral analyses I acknowledge Rolf Mildenberger. For further technical support and some discussions, I would like to thank Tom Frauenrath, Martin Haake, Anke Jurisch, Jens Köster, Werner Kraus, Anna Uffmann, Philipp Weniger, and Kathrin Windeck. Moreover, I want to thank Prof. Dr. K. Reicherter for allowing me to stay in his department for a further time and who also assisted me with regards to financial and administrative challenges during this time. For the financial support of this project (grants No Fl131/14) I gratefully acknowledge the DFG (German Research Foundation). I would also like to express my appreciation to the RAG-Deutsche Steinkohle and DMT (Deutsche Montan Technologie) for samples and technical support. For administrative support, I am especially thankful to all the secretaries, who supported me during the last five years: Bettina Lesmeister, Evelyn Bützler, Dorit Karnelis, Dorothee Degen and Olga Schefler. Finally, I want to thank all my colleagues for the time I enjoyed with them, especially Maggie, Gösta, Grütze and Werner – I will never forget the fantastic time in the Palaeo/NUG! V Abstract The idea of the present thesis was to combine different established methods in a high-resolution study on a short-timed interval of Duckmantian strata (Pennsylvanian/Upper Carboniferous) of the Ruhr Basin, Western Germany. Organic petrographical, palynological, sedimentological and organic geochemical techniques were used to obtain a huge data set, to support the argumentations and discussions. In doing so, these investigations were focused on two main goals: (a) the maturity and quality of source rocks and (b) the evolution of swamp environments. For this study, six coal-bearing seam successions were examined. Fresh drilling material was provided by the DSK coal mine Prosper Haniel in the Ruhr Basin, western Germany. All samples were taken from two multilateral wells. Experimental investigations comprise the following techniques: Sedimentological core description, maceral analyses, vitrinite reflectance, TOC, ash and Rock-Eval pyrolysis on sediments, kerogen concentrates and coal-mineral-mixtures, palynological investigations on miospores, and GC analyses on n-alkanes, and iso-alkanes. (a) Maturity and quality of source rocks This first part of the study focuses on the quality, quantity and maturity of coal and dispersed terrigenous organic matter. Furthermore, kerogen concentrates and coal-mineral-mixtures also were analysed. For the sampled interval samples show a vitrinite reflectance between 0.75 and 1.0 % with an increase of maturity towards the stratigraphic older and deeper seam successions. Average vitrinite reflectance of sediment samples is slightly higher than that of coal samples. The maturity trend also is reflected in the Tmax values of Rock-Eval pyrolysis or the C17/C27-relationship. Investigations on petroleum potential show a kerogen type III respectively II/III for the sampled interval. Differences between Rock-Eval parameters determined on whole rock samples and kerogen concentrates were observed, especially with respect to Hydrogen Index (HI) values. In coals, which were compared with dispersed organic matter of similar maceral composition, the HI is about two times as high as that of the sediment samples. In contrast, Oxygen Indices are much higher for dispersed type III kerogen than for coal, caused by the stronger degradation of organic compounds in the clastic environments as compared to the peat environments. However, Oxygen Indices clearly are influenced by decomposition of carbonate minerals. Furthermore, Hydrogen Indices of dispersed kerogen are influenced by mineral-matrix effects. Experiments with artificial mixtures of coal and minerals show that reactions with pyrite seem to reduce HI values of kerogen concentrates significantly. VII (b) Evolution of swamp environments The second part of the thesis focuses on palynological investigations on miospores to reconstruct the swamp evolution during the Duckmantian of the Ruhr Basin. In addition, sedimentological and organic petrographical data confirmed the interpretation. Based on published information of in situ spores the encountered miospores were assigned to their parent plants in order to reconstruct the vegetation history. In this study six plant associations were identified by using a Detrended Correspondence Analyses (DCA): lepidocarpacean association I, lepidocarpacean association II, lepidocarpacean – sigillarian association, lepidocarpacean – sphenophyll association, lepidocarpacean – fern association, and the subarborescent lycopsid association. Furthermore, coal petrographical GI/TPI and GWI/VI relationships also reflect these associations. Another new defined index, the water cover index (WCI), based on these palynological interpretations, reflects the ratio of hydrophilous/hygrophilous vs. mesophilous plants and gives additional information on the environment. In the sampled seam successions arborescent lycopsids are the most abundant plants, with a dominance of the miospore Lycospora. In 75 % of all samples the genus is represented with more than 50 % relative abundance. Hence, lepidocarpaceans such as Lepidophloios and Lepidodendron dominated the vegetation of the Ruhr Basin during the mid and late Duckmantian, forming flood plains and planar forest mires. Some variations are reflected in abundance of other spores. A greater influence of the sigillarian miospores Crassispora was typical for drier swamp margins, whereas densospore producing plants or sphenophylls characterized the stunted respectively scrambling vegetation of domed swamps. By contrast, fern influenced environments were rare during the Duckmantian. Recurring rhythmic successions of plant associations and depositional environments were noted in the studied interval: A lower flood plain is followed by peat substrate topogenous mires, which rise up and build an ombrogenous mire. After subsidence and recurrent flooding an upper flood plain was re- established. This general cycle is temporarily interrupted by other plant associations representing varying local environments. Drier sandbanks and swamp margin zones covered with sigillarians regularly occurred, implicating small environmental variations and a lateral shift of the swamp habitat. VIII Zusammenfassung Die Grundidee dieser Arbeit war die Kombination verschiedener Analyse-Methoden zur Durchführung einer hochauflösenden Studie. Hierfür wurde ein sehr kurzes Zeitintervall im Duckmantium (Pennsylvanium/Oberkarbon) des Ruhrbeckens/Deutschland ausgewählt. Die Anwendung von organsicher Petrographie, Palynologie, Sedimentologie sowie organischer Geochemie ermöglichten die Aufnahme eines sehr umfangreichen Datensatzes, dem eine statistisch gestützte Ergebnisdiskussion folgte und die zwei Hauptzielsetzungen hatte: (a) Reife und Qualität von Source Rocks und (b) Entwicklung von Sumpf-Environments. Im Laufe der Arbeit wurden sechs Flözbereiche ausgewertet. Von der Deutschen Steinkohle AG wurde frisch erbohrtes Kernmaterial (von zwei multilateralen Kernbohrungen aus Zeche Prosper Haniel, Ruhrgebiet) zur Verfügung gestellt. An diesem Material wurden verschiedenste Techniken durchgeführt: sedimentologische Bohrkernansprache, Mazeralanalyse, Vitrinitreflexionsmessungen, TOC-, Asche- und Rock-Eval-Pyrolysen an Sedimenten, Kerogenkonzentraten sowie Kohle-Mineral- Mischungen, palynologische Untersuchungen an Miosporen und GC-Analysen an n-Alkanen und iso- Alkanen. (a) Reife und Qualität von Source Rocks Im ersten Teil der Doktorarbeit wurden Qualität, Quantität und Reife von Kohlen und dispersem organischen Material untersucht.