Dinocyst zonation and lithostratigraphy of the Miocene succession in the Kasseburg borehole, Germany

This report presents the results of a biostratigraphic analysis of the Miocene succession in
the cored borehole Kasseburg based on fossil dinoflagellate cysts (dinocysts). The
borehole was located near the village Trittau, east of Hamburg, Germany (Fig. 1) and was
drilled in 1971.
In previous studies from 2010 and 2015 and 2016, respectively, it was proven that the dinocyst zonation of Dybkjær & Piasecki (2010), defined for the Danish Miocene succession, could be applied to the Miocene succession in the Schleswig-Holstein area. A detailed and well-documented correlation between the Miocene succession in the German Westerlangstedt borehole and the succession in the southern part of Jylland, Denmark, was presented in Dybkjær & Rasmussen (2010). In Dybkjær (2015) and in Dybkjær & Rasmussen (2016) the Schulensee borehole and the Schillsdorf borehole, respectively, were likewise dated and correlated with the Danish Miocene succession and with the Westerlangstedt borehole.

The purpose with the present study is to date the Miocene part of the Kasseburg borehole, to refer the succession to the dinocyst zonation of Dybkjær & Piasecki (2010) and to subdivide the succession into lithostratigraphic units.

The sampled Miocene part of the Kasseburg core (243 m - 45 m) is subdivided into the dinocyst zonation defined by Dybkjær & Piasecki (2010). Based on the dinocyst stratigraphy combined with the lithology and the gamma ray log pattern, the succession was further subdivided into the lithostratigraphic units of Rasmussen et al. (2010) and correlated with the successions in the Schillsdorf, Schulensee and Westerlangstedt boreholes, and with the Danish Miocene succession. The Miocene succession unconformably overlies Rupelian to lower Chattian clay, referred to dinocyst zone D14 of Köthe (1990; 2003). Minor reworking of Jurassic - lowermost Cretaceous and Palaeogene palynomorphs was found in some intervals (see below).

The following dinocyst zones were found:
308 m - 243 m: The D14 Zone
243 m - 235 m: The Thalassiphora pelagica Zone
235 m - 113 m: The Sumatradinium hamulatum/Cordosphaeridium cantharellus Zone
113 m - 112 m: The Exochosphaeridium insigne/Cousteaudinium aubryae Zone/lower Labyrinthodinium truncatum Zone
112 m - 47 m: The Labyrinthodinium truncatum/Unipontodinium aquaductum Zone
47 m - 46 m: The Achomosphaera andalousiense Zone

The Miocene succession thus comprises the interval from the lower Burdigalian (Lower Miocene) to the lower Serravallian (Middle Miocene).

Based on a combination of the dinocyst stratigraphy, the lithology of the samples and the geophysical log-pattern, the studied succession was subdivided into the Miocene lithostratigraphic units defined in the Danish area (Rasmussen et al., 2010) (the corresponding German lithostratigraphic units are mentioned in paranthese);

1) 243 m - 196 m: The Klintinghoved Formation (=”Unterer Glimmerton”)
2) 196 m - 114 m: The Bastrup Formation (= “Unterer Braunkohlensande”)
3) 114 m - 104 m: The Arnum Formation (= Hamburg Formation”)
4) 104 m - 58 m: The Odderup Formation (= “Obere Braunkohlensande”)
5) 58 m – 47 m: The Hodde Formation (= ”Obere Glimmerton”)
6) 47 m – 46 m: The Ørnhøj Formation (=”Obere Glimmerton”)

The Miocene succession is unconformably overlain by Quaternary deposits.