Petrographie und Reservoirqualität des Unterturon Glaukonitsandsteins im Feld Voitsdorf

Research output: ThesisMaster's Thesis

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Abstract

The Lower Turonian Glaukonitsandstone in the Voitsdorf Field (Alpine Foreland Basin, Upper Austria) is oil-bearing. However, because of low permeability, it was not possible till now to produce the oil economically. Within the frame of the present thesis, the sedimentologal and petrophysical characterstics of the Lower Turonian Glaukonitsandstone have been studied using samples from four wells in the Voitsdorf Field in order to reveal the reasons for its low permeability. In addition, based on the study results and a literature survey, different stimulation techniques are evaluated, which may result in increased permeability. The sedimentological results of the study justify a tripartioning of the Lower Turonian Glaukonitsandstone into an Upper, Middle and Lower Unit. All units exhibit a complex diagenetic evolution. This commences shortly after deposition with the formation of glaucony, followed by the formation of berthierine. An early clay coat formed around some grains, especially glaucony. Thereafter, the replacement of feldspars provided SiO2 for the formation of a first fine grained (20 µm) quartz cement generation. Cementation by calcite of the Lower Unit marks a change in pore water chemistry, which also stipulated the formation of pyrite in clay flakes. Local oxidation as well as dissolution in the Middle Unit represent the last diagenetic processes. Apart from dissolution pores, the majority of pores are micropores (

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Translated title of the contributionPetrography and Reservoir Quality of the Lower Turonian Glauconitic Sandstone of the Field Voitsdorf
Original languageGerman
QualificationDipl.-Ing.
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Award date26 Jun 2015
Publication statusPublished - 2015