- Email: [email protected]
The problem of the Tsagaiansk flora with regard to spore-and-pollen analytical data
Review of Palaeobotany and Palynology Elsevier PublishingCompany,Amsterdam- Printed in The Netherlands
THE PROBLEM OF THE TSAGAIANSK FLORA W I T H REGARD TO SPORE-AND-POLLEN ANALYTICAL DATA G. M. BRATZEVA
Geological Institute, Academy of Sciences, Moscow (U.S.S.R.) (Received August29, 1966)
SUMMARY
On the basis of studies of their leaf flora, the Tsagaiansk deposits of the Zeya-Bureya depression were referred by A. N. Kryshtofovichand T. N. Baikovskaia to the Danian Stage. However, when the flora was studied by spore-and-pollen analyses, throughout the entire mass of unconsolidated sediments, it was established that the Tsagaiansk deposits had been formed during the Maastrichtian. The established Maastrichtian index complex is characterized by a predominance of the species Aquilapollenites quadrilobus, A. polaris, A. cruciformis, A. subtilis, A. granulatus, Parviprojectus striatus, P. amurensis, Mancicorpus tenue, M. sodium, Wodehouseia spinata, Orbiculapollis globosus, and Tricolporopollenites radiatostriatus. Complexes of pollen belonging to various species of the family Proteaceae (Proteacidites asper, P. formosus, P. thalmanni, Symphyonema bellus, Beaupreidites elegan~(formis) and the family Loranthaceae (Elytranthe striatus, Loranthacites macrosolenoides), are invariably present. A similarity is noted between the Tsagaiansk spore-and-pollen complexes and the Maastrichtian complexes of North America.
INTRODUCTION The study of the Tsagaiansk flora of the Far East is of a great interest in connection with the establishment of the boundary between the Cretaceous and Tertiary Systems, and possible recognition of the Danian Stage in Asia. This flora is named after its locality in the outcrop Tsagaian of the Bureya (the right bank of the Bureya river, 40 km from the mouth); the suite bears the same name. It was distinguished by A. N. Kryshtofovich, who assigned this flora to the Danian Stage. The Tsagaiansk-flora type means a constant combination of various Trochodendroides with Metasequoia and Taxodium (BAIKOVSKAIA,1956).
Rev. Palaeobotan. Palynol., 2 (1967) 119-126
119
We studied a number of sections throughout the entire mass of unconsolidated sediments of the Zeya-Bureya depression, along the natural exposures and in wells. As the result of a detailed study we managed to find out that the flora of the Tsagaiansk Suite proper is rather peculiar and differs considerably from those observed in the sediments which underlie and overlap this suite. The deposits of the Tsagaiansk Suite occur--with wash-out and angular unconformity--either on the older crystalline basement, or on the sedimentary deposits of the Pojarcov (Lower Cretaceous) or Zavitinsk (Albian-Senonian) suites.
THE ZAVIT1NSK SUITE
The Zavitinsk Suite is composed of a series of terrigenous rocks which are represented by sandstones of various types, aleurolitic clays, and argellite-like clays with rather thin bands or lenses of carbonate rocks. In the complexes of the Zavitinsk Suite gymnospermous pollen prevails (50-60 ~). It belongs to the families Ginkgoaceae-Cycadaceae, Pinaceae and the genera Pinus, Pieea, Podocarpus, Cedrus, Daerydiumites, Taxodium and Glyptostrobus. Among the spores of ferns and lycopsids, the following spores are abundant: Anemia, Lygodium, Selaginella, and also Cieatrieosisporites dorogensis POTONI~ et GELLETICH, Cingulatisporites sp., Pilosisporites notensis COOKSON et DETTMAN, Leptolepidites verrucatus COUPER. Angiospermous pollen is present in considerably less quantity (15-20~), the prevalent form being a morphological type, viz.,
Tricolpites.
THE TSAGAIANSK SUITE
The Tsagaiansk Suite is represented by a series of obliquely-bedded light sands, sandstones, gritstones, conglomerates, aleurolites and clays. The thickness of the suite is up to 600 m.
Spores and pollen The composition of the spore-and-pollen complexes of the Tsagaiansk Suite is as follows: (1) Spores ( 1 5 - 2 0 ~ of the total number of spores and pollen grains): Sphagnum sp. Polypodiaeeae Lycopodium sp. Selaginella sp. Osmunda sp. 120
Rev. Palaeobotan.Palynol., 2 (1967) I 19-126
(2) Gymnosperms (25-35 %): Cedrus sp. C. parvisaccata ZAUER Abies sp. A. sibirieiformis ZAKLINSKAIA Pinus sp. Podocarpus sp. P. crispa CHLONOVA Picea sp. Cupressaceae Taxodium sp. Sequoia sp. S. aft. sempervirens ZAKLINSKAIA Ephedra multipartita CHLONOVA Equisetosporites barghoornii POCOCK (3a) Angiosperms (angiospermous pollen is predominant, i.e., 50-70%, almost half of it being identified according to a natural system): Proteacidites asper SAMOILOVICH P. formosus SAMOILOVICH P. thalmanni ANDERSON Symphyonema bellus BRATZEVA Beaupreidites elegansiformis CooKsoN (Plate I J) Elytranthe striatus COUPER Loranthacites macrosolenoides N. D. MCHEDLISHVILI(Plate I H) Ulmoideipires ANDERSON Alnus sp. Myrica sp. Quercites sparsus SAMOILOVICH Altingia sp. Bombacaceae Platanus sp. (3b) The angiosperm-pollen composition of form taxa is particularly varied and rich: Aquilapollenites quadrilobus ROUSE A. polaris FUNKHOUSER A. cruciformis N. D. MCHEDLISHVILI(Plate I K) A. subtilis N. D. MCHEDLISHVILI A. granulatus N. D. MCHEDLISHVILI Parviprojectus striatus N. D. MCHEDLISHVILI P. amurensis BRATZEVA Mancicorpus tenue N. D. MCHEDLISHVILI(Plate I G) M. sodium N. D. MCHEDLISHVILI
Rev. Palaeobotan.Palynol., 2 (1967) 119-126
121
Wodehouseia spinata STANLEY(Plate [ L) Orbiculapollis globosus CHLONOVA h'icolporopollenites radiatostriatus (N. D. MCHEDLISHVtL0 BRATZEVA (Plate I M)
T. gracilis BRATZEVA Gothanipollis santaloides ZAKLINSKAIA G. elegans ZAKLINSKAIA The characteristic features of the Tsagaiansk flora are: (1) the predominance of plants producing pollen of various species of Aquilapollenites, Parviprojectus, Mancicorpus, Wodehouseia; and (2) the presence of various species of the families Proteaceae and Loranthaceae.
Comparisons The correlation of the Tsagaiansk spore-and-pollen complex with the Upper Cretaceous complexes of contiguous regions revealed the greatest similarity between these complexes and those from Maastrichtian deposits in Asia and the Far East, which are characterized by their fauna. It is interesting to note that with various floristic compositions of the Maastrichtian spore-and-pollen complexes--characterizing various palaeofloristic provinces (Turkmanian-Kazakhstanian and eastern Siberian)--the complex of the index species is the same. Thus in the Maastrichtian marine deposits of northern Kazakhstan (PoNoMARENKO,1966) a complex is distinguished, characterized by the presence of species of Aquilapollenites, Mancicorpus, as well as Proteacidites, alongside a representative of the Normapolles PFLUG, which is absent in the Zeya-Bureya depression.
PLATE I Characteristic pollen grains from Upper Cretaceous-Palaeogene deposits of the Zeya-Bureya Basin. Kivdinsk Suite (Paleocene-Eocene): A. Carya sp. B. Anacolosidites supplingensis C. Corylopsis sp. D. Myrica sp. E. Cornptonia sp. F. Triatriopollenites confusus Tsagaiansk Suite (Maastrichtian): G. Mancicorpus tenue H. Loranthaeites macrosolenoides J. Beaupreaidites elegansiformis K. Aquilapollenites eruciformis L. Wodehouseia spinata M. Tricolporopollenites radiatostriatus
122
Rev. Palaeobotan. Palynol., 2 (1967) 119-126
PLATE I
Rev. Palaeobotan. Palynol., 2 (1967) 119-126
123
The similarity of the Tsagaiansk complex to an index complex of genera and species of Maastrichtian age enabled us to attribute the Tsagaiansk deposits to the Maastrichtian. The spore-and-pollen complex, having an analogous composition of the index species, are described from the Maastrichtian deposits of the WestSiberian lowland, Yakutia, Kamchatka and the Anadyr river region. When comparing the Tsagaiansk flora with the coeval floras of North America (ROUSE, 1957; ANDERSON, 1960; FUNKHOUSER, 1961; STANLEY, 1961), a striking similarity is observed between the index species as well as the complex as a whole. Despite the common complex of the index forms, the floristic composition of the Maastrichtian deposits of various regions is not identical. The flora of the Pacific coast of North America and eastern Asia where the main localities of the Tsagaiansk flora occur, is characterized by a large variety of Ulmaceae, whereas in the coeval deposits of the western parts of Asia Ulmaceae are not found. The representatives of the morphological branch Normapolles PFLUG, present in the flora of western Asia were not observed in the flora of the Pacific coast of North America and eastern Asia. The region of the Zeya-Bureya depression in Maastrichtian time was a part of the East-Siberian floristic province of the Eurasian continent (ZAKLINSKAIA,1963).
THE KIVDINSKSUITE
The Tsagaiansk Suite is overlapped by the deposits of the coal-bearing Kivdinsk Suite which is in the main represented by sands with rare bands of aleurolites and clays with brown coal seams in the middle part of the section. In the spore-and-pollen spectra of the lower part of the suite gymnosperms are represented by the pollen of the same families as in the underlying suites, viz., Pinaceae, Podocarpaceae, and Taxodiaceae. Prevalent spores are the following: representatives of the Polypodiaceae, and many spores of Sphagnum, Lycopodium, and Osmunda. In the group of angiospermous pollen - as compared to the angiospermous pollen in the Tsagaiansk complex- an intense impoverishment of the specific composition is observed, three-apertured pollen grains being predominant. These pollen grains mainly belong to the Myricaceae (Myrica sp. (Plate I D), Comptonia sp., (Plate I E) C. sibirica GLADKOVA),whereas pollen grains of a complex morphological structure gradually disappear. Pollen grains of the family Betulaceae are not numerous; the pollen of the family Juglandaceae is abundant (viz., Juglans, Carya (Plate I A), and Pterocarya). Also pollen of representatives of the families Menispermaceae, Fagaceae (Quercites SAMOILOVICH) and Platanaceae (Platanussp.) may be observed. In the second complex of the Kivdinsk Suite in the gymnospermous-pollen group the number of pollen grains from the family Pinaceae considerably decreases 124
Rev. Palaeobotan. Pal.vnol., 2 (1967) 119 126
(the genus Pinus remains) and the number of pollen grains of the families Taxodiaceae and Cupressaceae increases. In the group of angiospermous pollen grains, alongside the pollen of the families Myricaceae, Betulaceae, Fagaceae, we may observe a considerable quantity of pollen grains of representatives of the families Olacaceae (Anacolosidites primigenius ZAKLINSKAIA,A. tenuiplicus ZAKLINSKAIA, A. suppligensis (PFLUG) KRUTZSCH(Hate I B), and Hamamelidaceae (Corylopsis, (Plate I C), Fothergilla, Hamamelis). Pollen grains of the Eucommiaceae and Onagraceae appear. In both the spectra, especially in the lower one, many other pollen grains are found; these may be assigned to the taxa Triporopollenites PFLUGand Triatriopollenites PFLUG (T. confusus ZAKLINSKAIA;Plate I F). Among the representatives of the genus Aquilapollenites which are widespread in the Maastrichtian, only one species, A. quadrilobus ROUSE, is sporadically found in the lower beds of the Kivdinsk Suite. In the spectra of the Kivdinsk Suite there is no pollen of the index species belonging to the families Proteaceae and Loranthaceae. Thus, we can not consider the floras of the Tsagaiansk and Kivdinsk Suites to be contemporaneous.
CONCLUSIONS The establishment of the heterochronous "sub-suites" of the Tsagaiansk Suite, based on pollen-analytical data, cannot be considered well enough founded, because the sediments of the Tsagaiansk Suite throughout the whole series of strata contain only the Maastrictian complex of spores and pollen. In the upper layers of the suite, no complexes were found which could serve as the basis for the recognition of an independent "Danian" flora. The spore-and-pollen complexes which are younger than the Tsagaiansk one were distinguished from the deposits of the Kivdinsk Suite. The lowest of the deposits, i.e., the oldest complexes still, contain Maastrichtian relics (Aquilapollenites sp. and A. quadrilobus), but in general composition it is a Paleogene complex. Thus, the so-called "Danian" flora of Tsagaiansk certainly belongs to the Maastrichtian. The Maastrichtian flora is replaced upwards by a Palaeogene one which considerably differs from the complex of the youngest floras of the Upper Senonian.
REFERENCES
ANDERSON,R., 1960. Cretaceous-Tertiarypalynology,eastern side of the San Juan Basin, New Mexico. New Mexico, Bur. Mines Mineral Resources, Mem., 6:36 pp. BAIKOVSKA/AT. N., 1956. The Upper Cretaceous flora of northern Asia. Paleobotanika, Akad. Nauk S.S.S.R., Moscow, I1:49-193 (in Russian). FUNrdtOUSER,J., 1961. Pollen of the genus Aquilapollenites. Micropaleontology, 7(2): 193-198. Rev. Palaeobotan. Palynol., 2 (1967) 119-126
125
PONOMARENKO,Z. K., 1966. The age and palaeogeographical environments of bauxite formation in Kazakhstan. In: M. I. NEUSTADT (Editor), The Importance ofPalynological Analysis for Stratigraphic andPaleofloristic Investigations. Nauka, Moscow, pp. 148-154 (in Russian). ROUSE, G., 1957. The application of the new nomenclatural approach to Upper Cretaceous plant microfossils from western Canada. Can. J. Botany, 35(3): 359-375. STANLEY,E. A., 1961. A new sporomorph genus from South Dakota. Pollen Spores, 3(1): 155-162. ZAKLINSKAIA,E. O., 1963. Angiospermous pollen and itssignificance for the stratigraphy of the Upper Cretaceous and Palaeogene. Tr. Inst. Geol. Nauk, Akad. Nauk S.S.S.R., Geol. Set., 74:258 pp. (in Russian).
126
Rev. Palaeobotan. Palynol., 2 (1967) 119-126
THE PROBLEM OF THE TSAGAIANSK FLORA W I T H REGARD TO SPORE-AND-POLLEN ANALYTICAL DATA G. M. BRATZEVA
Geological Institute, Academy of Sciences, Moscow (U.S.S.R.) (Received August29, 1966)
SUMMARY
On the basis of studies of their leaf flora, the Tsagaiansk deposits of the Zeya-Bureya depression were referred by A. N. Kryshtofovichand T. N. Baikovskaia to the Danian Stage. However, when the flora was studied by spore-and-pollen analyses, throughout the entire mass of unconsolidated sediments, it was established that the Tsagaiansk deposits had been formed during the Maastrichtian. The established Maastrichtian index complex is characterized by a predominance of the species Aquilapollenites quadrilobus, A. polaris, A. cruciformis, A. subtilis, A. granulatus, Parviprojectus striatus, P. amurensis, Mancicorpus tenue, M. sodium, Wodehouseia spinata, Orbiculapollis globosus, and Tricolporopollenites radiatostriatus. Complexes of pollen belonging to various species of the family Proteaceae (Proteacidites asper, P. formosus, P. thalmanni, Symphyonema bellus, Beaupreidites elegan~(formis) and the family Loranthaceae (Elytranthe striatus, Loranthacites macrosolenoides), are invariably present. A similarity is noted between the Tsagaiansk spore-and-pollen complexes and the Maastrichtian complexes of North America.
INTRODUCTION The study of the Tsagaiansk flora of the Far East is of a great interest in connection with the establishment of the boundary between the Cretaceous and Tertiary Systems, and possible recognition of the Danian Stage in Asia. This flora is named after its locality in the outcrop Tsagaian of the Bureya (the right bank of the Bureya river, 40 km from the mouth); the suite bears the same name. It was distinguished by A. N. Kryshtofovich, who assigned this flora to the Danian Stage. The Tsagaiansk-flora type means a constant combination of various Trochodendroides with Metasequoia and Taxodium (BAIKOVSKAIA,1956).
Rev. Palaeobotan. Palynol., 2 (1967) 119-126
119
We studied a number of sections throughout the entire mass of unconsolidated sediments of the Zeya-Bureya depression, along the natural exposures and in wells. As the result of a detailed study we managed to find out that the flora of the Tsagaiansk Suite proper is rather peculiar and differs considerably from those observed in the sediments which underlie and overlap this suite. The deposits of the Tsagaiansk Suite occur--with wash-out and angular unconformity--either on the older crystalline basement, or on the sedimentary deposits of the Pojarcov (Lower Cretaceous) or Zavitinsk (Albian-Senonian) suites.
THE ZAVIT1NSK SUITE
The Zavitinsk Suite is composed of a series of terrigenous rocks which are represented by sandstones of various types, aleurolitic clays, and argellite-like clays with rather thin bands or lenses of carbonate rocks. In the complexes of the Zavitinsk Suite gymnospermous pollen prevails (50-60 ~). It belongs to the families Ginkgoaceae-Cycadaceae, Pinaceae and the genera Pinus, Pieea, Podocarpus, Cedrus, Daerydiumites, Taxodium and Glyptostrobus. Among the spores of ferns and lycopsids, the following spores are abundant: Anemia, Lygodium, Selaginella, and also Cieatrieosisporites dorogensis POTONI~ et GELLETICH, Cingulatisporites sp., Pilosisporites notensis COOKSON et DETTMAN, Leptolepidites verrucatus COUPER. Angiospermous pollen is present in considerably less quantity (15-20~), the prevalent form being a morphological type, viz.,
Tricolpites.
THE TSAGAIANSK SUITE
The Tsagaiansk Suite is represented by a series of obliquely-bedded light sands, sandstones, gritstones, conglomerates, aleurolites and clays. The thickness of the suite is up to 600 m.
Spores and pollen The composition of the spore-and-pollen complexes of the Tsagaiansk Suite is as follows: (1) Spores ( 1 5 - 2 0 ~ of the total number of spores and pollen grains): Sphagnum sp. Polypodiaeeae Lycopodium sp. Selaginella sp. Osmunda sp. 120
Rev. Palaeobotan.Palynol., 2 (1967) I 19-126
(2) Gymnosperms (25-35 %): Cedrus sp. C. parvisaccata ZAUER Abies sp. A. sibirieiformis ZAKLINSKAIA Pinus sp. Podocarpus sp. P. crispa CHLONOVA Picea sp. Cupressaceae Taxodium sp. Sequoia sp. S. aft. sempervirens ZAKLINSKAIA Ephedra multipartita CHLONOVA Equisetosporites barghoornii POCOCK (3a) Angiosperms (angiospermous pollen is predominant, i.e., 50-70%, almost half of it being identified according to a natural system): Proteacidites asper SAMOILOVICH P. formosus SAMOILOVICH P. thalmanni ANDERSON Symphyonema bellus BRATZEVA Beaupreidites elegansiformis CooKsoN (Plate I J) Elytranthe striatus COUPER Loranthacites macrosolenoides N. D. MCHEDLISHVILI(Plate I H) Ulmoideipires ANDERSON Alnus sp. Myrica sp. Quercites sparsus SAMOILOVICH Altingia sp. Bombacaceae Platanus sp. (3b) The angiosperm-pollen composition of form taxa is particularly varied and rich: Aquilapollenites quadrilobus ROUSE A. polaris FUNKHOUSER A. cruciformis N. D. MCHEDLISHVILI(Plate I K) A. subtilis N. D. MCHEDLISHVILI A. granulatus N. D. MCHEDLISHVILI Parviprojectus striatus N. D. MCHEDLISHVILI P. amurensis BRATZEVA Mancicorpus tenue N. D. MCHEDLISHVILI(Plate I G) M. sodium N. D. MCHEDLISHVILI
Rev. Palaeobotan.Palynol., 2 (1967) 119-126
121
Wodehouseia spinata STANLEY(Plate [ L) Orbiculapollis globosus CHLONOVA h'icolporopollenites radiatostriatus (N. D. MCHEDLISHVtL0 BRATZEVA (Plate I M)
T. gracilis BRATZEVA Gothanipollis santaloides ZAKLINSKAIA G. elegans ZAKLINSKAIA The characteristic features of the Tsagaiansk flora are: (1) the predominance of plants producing pollen of various species of Aquilapollenites, Parviprojectus, Mancicorpus, Wodehouseia; and (2) the presence of various species of the families Proteaceae and Loranthaceae.
Comparisons The correlation of the Tsagaiansk spore-and-pollen complex with the Upper Cretaceous complexes of contiguous regions revealed the greatest similarity between these complexes and those from Maastrichtian deposits in Asia and the Far East, which are characterized by their fauna. It is interesting to note that with various floristic compositions of the Maastrichtian spore-and-pollen complexes--characterizing various palaeofloristic provinces (Turkmanian-Kazakhstanian and eastern Siberian)--the complex of the index species is the same. Thus in the Maastrichtian marine deposits of northern Kazakhstan (PoNoMARENKO,1966) a complex is distinguished, characterized by the presence of species of Aquilapollenites, Mancicorpus, as well as Proteacidites, alongside a representative of the Normapolles PFLUG, which is absent in the Zeya-Bureya depression.
PLATE I Characteristic pollen grains from Upper Cretaceous-Palaeogene deposits of the Zeya-Bureya Basin. Kivdinsk Suite (Paleocene-Eocene): A. Carya sp. B. Anacolosidites supplingensis C. Corylopsis sp. D. Myrica sp. E. Cornptonia sp. F. Triatriopollenites confusus Tsagaiansk Suite (Maastrichtian): G. Mancicorpus tenue H. Loranthaeites macrosolenoides J. Beaupreaidites elegansiformis K. Aquilapollenites eruciformis L. Wodehouseia spinata M. Tricolporopollenites radiatostriatus
122
Rev. Palaeobotan. Palynol., 2 (1967) 119-126
PLATE I
Rev. Palaeobotan. Palynol., 2 (1967) 119-126
123
The similarity of the Tsagaiansk complex to an index complex of genera and species of Maastrichtian age enabled us to attribute the Tsagaiansk deposits to the Maastrichtian. The spore-and-pollen complex, having an analogous composition of the index species, are described from the Maastrichtian deposits of the WestSiberian lowland, Yakutia, Kamchatka and the Anadyr river region. When comparing the Tsagaiansk flora with the coeval floras of North America (ROUSE, 1957; ANDERSON, 1960; FUNKHOUSER, 1961; STANLEY, 1961), a striking similarity is observed between the index species as well as the complex as a whole. Despite the common complex of the index forms, the floristic composition of the Maastrichtian deposits of various regions is not identical. The flora of the Pacific coast of North America and eastern Asia where the main localities of the Tsagaiansk flora occur, is characterized by a large variety of Ulmaceae, whereas in the coeval deposits of the western parts of Asia Ulmaceae are not found. The representatives of the morphological branch Normapolles PFLUG, present in the flora of western Asia were not observed in the flora of the Pacific coast of North America and eastern Asia. The region of the Zeya-Bureya depression in Maastrichtian time was a part of the East-Siberian floristic province of the Eurasian continent (ZAKLINSKAIA,1963).
THE KIVDINSKSUITE
The Tsagaiansk Suite is overlapped by the deposits of the coal-bearing Kivdinsk Suite which is in the main represented by sands with rare bands of aleurolites and clays with brown coal seams in the middle part of the section. In the spore-and-pollen spectra of the lower part of the suite gymnosperms are represented by the pollen of the same families as in the underlying suites, viz., Pinaceae, Podocarpaceae, and Taxodiaceae. Prevalent spores are the following: representatives of the Polypodiaceae, and many spores of Sphagnum, Lycopodium, and Osmunda. In the group of angiospermous pollen - as compared to the angiospermous pollen in the Tsagaiansk complex- an intense impoverishment of the specific composition is observed, three-apertured pollen grains being predominant. These pollen grains mainly belong to the Myricaceae (Myrica sp. (Plate I D), Comptonia sp., (Plate I E) C. sibirica GLADKOVA),whereas pollen grains of a complex morphological structure gradually disappear. Pollen grains of the family Betulaceae are not numerous; the pollen of the family Juglandaceae is abundant (viz., Juglans, Carya (Plate I A), and Pterocarya). Also pollen of representatives of the families Menispermaceae, Fagaceae (Quercites SAMOILOVICH) and Platanaceae (Platanussp.) may be observed. In the second complex of the Kivdinsk Suite in the gymnospermous-pollen group the number of pollen grains from the family Pinaceae considerably decreases 124
Rev. Palaeobotan. Pal.vnol., 2 (1967) 119 126
(the genus Pinus remains) and the number of pollen grains of the families Taxodiaceae and Cupressaceae increases. In the group of angiospermous pollen grains, alongside the pollen of the families Myricaceae, Betulaceae, Fagaceae, we may observe a considerable quantity of pollen grains of representatives of the families Olacaceae (Anacolosidites primigenius ZAKLINSKAIA,A. tenuiplicus ZAKLINSKAIA, A. suppligensis (PFLUG) KRUTZSCH(Hate I B), and Hamamelidaceae (Corylopsis, (Plate I C), Fothergilla, Hamamelis). Pollen grains of the Eucommiaceae and Onagraceae appear. In both the spectra, especially in the lower one, many other pollen grains are found; these may be assigned to the taxa Triporopollenites PFLUGand Triatriopollenites PFLUG (T. confusus ZAKLINSKAIA;Plate I F). Among the representatives of the genus Aquilapollenites which are widespread in the Maastrichtian, only one species, A. quadrilobus ROUSE, is sporadically found in the lower beds of the Kivdinsk Suite. In the spectra of the Kivdinsk Suite there is no pollen of the index species belonging to the families Proteaceae and Loranthaceae. Thus, we can not consider the floras of the Tsagaiansk and Kivdinsk Suites to be contemporaneous.
CONCLUSIONS The establishment of the heterochronous "sub-suites" of the Tsagaiansk Suite, based on pollen-analytical data, cannot be considered well enough founded, because the sediments of the Tsagaiansk Suite throughout the whole series of strata contain only the Maastrictian complex of spores and pollen. In the upper layers of the suite, no complexes were found which could serve as the basis for the recognition of an independent "Danian" flora. The spore-and-pollen complexes which are younger than the Tsagaiansk one were distinguished from the deposits of the Kivdinsk Suite. The lowest of the deposits, i.e., the oldest complexes still, contain Maastrichtian relics (Aquilapollenites sp. and A. quadrilobus), but in general composition it is a Paleogene complex. Thus, the so-called "Danian" flora of Tsagaiansk certainly belongs to the Maastrichtian. The Maastrichtian flora is replaced upwards by a Palaeogene one which considerably differs from the complex of the youngest floras of the Upper Senonian.
REFERENCES
ANDERSON,R., 1960. Cretaceous-Tertiarypalynology,eastern side of the San Juan Basin, New Mexico. New Mexico, Bur. Mines Mineral Resources, Mem., 6:36 pp. BAIKOVSKA/AT. N., 1956. The Upper Cretaceous flora of northern Asia. Paleobotanika, Akad. Nauk S.S.S.R., Moscow, I1:49-193 (in Russian). FUNrdtOUSER,J., 1961. Pollen of the genus Aquilapollenites. Micropaleontology, 7(2): 193-198. Rev. Palaeobotan. Palynol., 2 (1967) 119-126
125
PONOMARENKO,Z. K., 1966. The age and palaeogeographical environments of bauxite formation in Kazakhstan. In: M. I. NEUSTADT (Editor), The Importance ofPalynological Analysis for Stratigraphic andPaleofloristic Investigations. Nauka, Moscow, pp. 148-154 (in Russian). ROUSE, G., 1957. The application of the new nomenclatural approach to Upper Cretaceous plant microfossils from western Canada. Can. J. Botany, 35(3): 359-375. STANLEY,E. A., 1961. A new sporomorph genus from South Dakota. Pollen Spores, 3(1): 155-162. ZAKLINSKAIA,E. O., 1963. Angiospermous pollen and itssignificance for the stratigraphy of the Upper Cretaceous and Palaeogene. Tr. Inst. Geol. Nauk, Akad. Nauk S.S.S.R., Geol. Set., 74:258 pp. (in Russian).
126
Rev. Palaeobotan. Palynol., 2 (1967) 119-126