Kovács I. (szerk.): A Magyar Természettudományi Múzeum évkönyve 78. (Budapest 1986)
Hably, L.: The macroflora of the borehole Kiscell-1 in Budapest
ANNALES HISTORICO-NATURALES MUSEI NATIONALIS HUNGARICI Tomus 78. Budapest, 1986 p. 31-40The macroflora of the borehole Kiscell-1 in Budapest by L. HABLY, Budapest Abstract — The macroflora of the borehole Kiscell-1 has been studied. It became clear during the complex geological investigation that the age of the flora is Late Oligocène and belongs to the NP-23 nannoplankton zone. The flora is typically palaeotropical. Most of the species are thermophilous elements and a lot of them show xerophilous characteristics. With 1 figure and 3 photoplates. The age of the flora Analysis of several exposures and cores were initiated in Hungary durind the investigation of the Eocene-Oligocene boundary problem (BÁLDI, HORVÁTH, NAGYMAROSY & VARGA 1984). The analysis was based on the results of biostratigraphy (nannoplanktons, dinoflagellates, pollens, macroflora, foraminiferids, large foraminiferids, ostracods, molluscs), magnetostratigraphy, sedimentology (SEM-records, mineralogy, gcochcmical O and C isotopic and sedimentological analyses) and the K-Ar method of radiometrical datind. Among the numerous exposures and cores only the borehole Kiscell-1 contained some macroflora. The geological section can be seen in Fig. 1. The last presence of Discoaster saipanensis and D. barbadiensis and the abundance of Zygrhablitus bijugatus, Lanternitus minutus at a depth of 28 m indicates the boundary of the NP 20/21 zone. The planctonic foraminiferids, that is, the disappearance of Subbotina linaperta and the rare appearance of ,,small globigerinoides" indicate the Eocene-Oligocene boundary at the same depth. The boundary of the NP 21/22 zone is at 78 m and that of the NP 22/23 zone is at 55.5 m. The transitional planktonic foraminiferid zone can be estimated as between 98-84 m. The P 18 zone is marked with the abundance of Globigerina linerovskae, Globorotalia postcretacea, Globorotalia mundo and Globorotalia brevispira specimens. There is practically no foraminiferid fauna above 55 m. However, macroflora appears just above this level, the first leaf remains were found at a depth of 48.1 m. It seems probable that this is in connection with the petrological change that occurs at about 51.3 m where slightly laminated Tard Clay is replaced by strongly laminated Tard Clay. Thus we can assume the NP 23 nannoplankton zone to be probable for the age of the flora. This zone contains the euxin layers of the Upper Tard Clay. Macroflora Relatively well-preserved macroflora could be found in borehole Kiscell-1. Most of the remains are leaf fragments, there is only one fruit and there are some flower imprints. Not only the imprints of the leaves have been preserved but also their texture, so they can also be used in the analysis of the epidermis.
