N. ICHINNOROV: Discovery of Early Cretaceous pollen and spores from
the Shaazan Govi area, Southeastern Mongolia------ 2 - 7
To Abstract (linked to Full Text)
L. URANBILEG: The fitostratigraphical scale of Upper Permian coal deposits
in Southern Mongolia ------ 8
To Abstract
L. URANBILEG: The fitogeographical position in Upper Permian, Southern
Mongolia ------ 9
To Abstract
Book review: Tectonics, Magmatism, and Metallogeny of Mongolia ------
10 - 11
To Abstract
Geoscience on the Net ------ 12 - 13
From Newspaper in Mongolia ------ 14 - 15
Forthcoming Events ------ 16 - 20
Abstract
Palynological analyses were done for the Lower Cretaceous sediments
of Shaazan Govi area. In result of palynological study, two assemblages,
assemblage I and assemblage II, are recognized for Shinekhudag and Khukhteeg
Formations, respectively. The assemblage I in Shinekhudag Formation indicates
Hauterivian-Barremian, and the assemblage II in Khukhteeg Formation indicates
Albian age. These are correlated to spore-pollen assemblages of West Siberia,
Transbaikalia, North America and North China.
To Full Text (html 38 KB).
(This text is linked to figures)
Abstract
During Permian period in the Mongolian territory
was happened the accumulation of mainly continental and littoral to submarine
floras deposits. Stratigrafical scale based on the floras assemblages is
needed for geological mapping and investigation works in the field of development
of this deposits.
By detailed fitostratigraphical investigations for
dismemberment of coal deposits in Southern Mongolia, it has been clear
that these deposits include mainly Cordaitian assemblages, but at least
Pteridospermales and ferns. The analysis of composition and ages of floras
assemblages from the coal deposits of Southern Mongolia estabilished distinction
of two coal series at all points of coal deposits from this region, Kazanian
- early tatarian and Upper tatarian. The elaboration of dismembermental
scheme of Kazanian - early tatarian deposits of this region includes nine
fitostratigraphical units of different ranges.
As mentioned the above, the detailed fitostratigraphical
scale is obviously useful for the dismembermental deposits, therefore the
coal deposits should be fitostratigraphically analyzed not only in Southern
Mongolia but also in the whole Mongolia.
Abstract
The essential Cordaitian Upper Permian flora of
Southern Mongolia is very similar to the flora from the Central region
of Angaraland (Sibirian province). On the another hand, the Southern Mongolian
flora is distinguished by some peculiar composition, which is not characteristic
in Sibirian flora as followings;
a) Presence of the early coal series, which is characteristic by analysis
of Central Angarian assemblages and odd admixture of Kazanian and Gondwanian
elements, well as Southern Primorian endemic;
b) Presence of the upper coal series of plants (Lepidophyta - Takhtajanodoxa,
Peltaspermalian pteridosperms with foliage Pursongia and fruitification
Peltaspermopsis), which is characteristic for Upper Tatarian flora from
the Russian stone and Southern Priuralia;
c) Isolation from the Upper time section of notcordaitian Ð pursongian
- callipterisian assemblage, which have not a sincere analysis in another
regions of Angaraland.
The such mixedly characteristic of floras assemblages
of Southern Mongolia indicated that this region is disposed in the near
boundary of Sibirian and Subangarian paleofloristic provinces in Upper
tatarian epoch.
At this geological time the Southern Mongolia is
one example of the an Ecoton which was located between two above mentioned
provinces. In the Kazanian - early tatarian epocha for fitogeographical
position, this region belongs to the Dalnevostoc subprovince of Sibirian
paleofloristic province.
"Tectonics, Magmatism, and Metallogeny of Mongolia" Edited by A.B. Dergunov, Routledge, 11 New Fetter Lane, London EC4P 4EE, 2001 ISBN 0-415-26727-7
This new book was edited by A.B. Dergunov, Geological
Institute, Russian Academy of Sciences, Moscow, Russia. This is the first
systematic description of basic geological framework of Mongolia in English.
This volume is composed of the following chapters and sections.
Preface / 1. Precambrian Microcontinents(A.B. Dergunov) / 2. The Caledonides
(A.B. Dergunov), Late Caledonides of South Mongolia (S.V. Ruzhentsev) /
3. The Variscan Belt of South Mongolia and Dzungaria (S.V. Ruzhentsev )
/ 4. Middle Paleozoic Continental Margin Magmatism of Mongolia (V.V. Yarmolyuk
and V.I. Kovalenko) / 5. The Indo-Sinides of Inner Mongolia (S.V. Ruzhentsev)
/ 6. Upper Paleozoic Continental Margin Magmatism of Mongolia (V.V. Yarmolyuk
and V.I. Kovalenko) / 7. The Mesozoic-Cainezoic of Mongolia (V.V. Yarmolyuk
and V.I. Kovalenko) / 8. Ore Deposits and Metallogeny of Mongolia (V.I.
Kovalenko and V.V. Yarmolyuk) / Conclusion: Tectonic Development and Geodynamics
of Central Asia (S.V. Ruzhentsev, V.I. Kovalenko, A.B. Dergunov, and V.V.
Yarmolyuk)
In this volume, many large scale geological maps
and geological sections are present, and conveniently the localities of
these are shown in Figure 1 which is the small scale map about Pre-Mesozoic
tectonic zonation of Mongolia. In the chapters on magmatism, many chemical
data are shown in some tables. Those data are plotted in the SiO2-(Na2O+K2O)
classification diagram. The readers must notice difference between the
USSR classification and the IUGS recommendation. For example, alkali basalt
and subalkali basalt in the IUGS recommendation are called subalkali basalt
and basalt in the USSR (and this volume), respectively.
In final chapter (conclusion), tectonic processes
from the Riphean to Cenozoic are discussed based on the theory of New Global
Tectonics. This volume will become a primary source of references for graduated
students and researchers.