Review Section

Brodsky, A. A., HYDROCHEMICAL PROSPECTING FOR COPPER: State Technical Press for Geology and Conservation of Resources, Moscow, 1956, 84 pp., 42 refs. A Review by W. D. Romey.     

Review Section

ABSTRACT

The bulk composition of silicic igneous rocks hovers directly over the ‘minimum melt’ located on the NaAlSi₃O₈–KAlSi₃O₈–SiO₂ ternary. It is universally accepted that these rocks are igneous, reflecting the thermodynamic equilibrium between minerals and melt. However, there is a contradiction between the use of this phase diagram and current models of differentiation: fractional crystallization or partial melting (or any mechanical separation process) implies granites were melts extracted from a quartz-bearing residue.

Here, I propose that a thermodynamically controlled process, wet thermal migration, provides a more consistent explanation for producing silicic rocks. This process, when coupled with slow incremental emplacement of sills, allows magmatic differentiation to take place without mechanical separation and produces minimum-melt compositions from input magmas not saturated in quartz. Examination of phase equilibria in the SiO₂–Al₂O₃–Na₂O–K₂O–H₂O system, as well as assessment of thermodynamic models, provides a template for understanding the wet thermal migration process (diffusion-based differentiation of crystal-mush in a temperature gradient). Phase equilibria in SiO₂–Na₂O–K₂O–Al₂O₃ indicate a cotectic surface between quartz and alkali feldspar slopes down-temperature as melt peralkalinity increases. Experiments show quartz and two feldspars coexist with a single water-rich (>40 wt.% H₂O) melt at 400°C and 0.1 GPa. Modelling suggests that development of water-rich melt at the hot end of a temperature gradient drives the process. Given the propensity of alkalis to rapidly diffuse down-temperature gradients and form these melts, small amounts (<5%) of interconnected melt form, leading to the differentiation of partially molten materials by wet thermal migration.

Because the quartz-feldspar cotectic ranges from 650°C to 330°C, granites can reflect formation by a process that never involves the existence of rhyolitic melt. If this is correct, the process has implications for understanding the formation of plutons and batholiths and, therefore, the continental crust.     

Review Section

CONTEMPORARY SEDIMENTS OF THE CASPIAN SEA, a Symposium of papers by M. V. Klenova, V. F. Solovyev, N. M. Arutyunova, P. G. Popov, L. A. Yastrebova, V. P. Baturin, and E. K. Kopylova, 302 pp., published by Academy of Sciences of the USSR, Moscow, 1956. A Review by Robert L. Folk, University of Texas.

V.F. Solovyev, PECULIARITIES OF DIFFERENTIATION OF THE PRESENT CASPIAN SEDIMENTS IN THE REGION OF APSHERON, pp. 118-136, 2 figs., 6 tables, 9 refs.

M.V. Klenova, MATTER IN SUSPENSION IN THE KURA RIVER, p. 151-174, 6 figs., 12 tables, 14 refs.

N.M. Arutyunova, MINERAL COMPOSITION OF THE BAKU ARCHIPELAGO SEDIMENTS, p. 175-185, 1 fig., 7 tables, 11 refs.

P.G. Popov, "STRATIFICATION OF SEDIMENTS IN THE CASPIAN SEA, p. 186-241, 13 figs., 18 tables, 35 refs.

M.V. Klenova and L. A. Yastrebova, SEDIMENTS IN THE NORTHERN PART OF THE CASPIAN SEA, p. 242-271, 7 figs., 16 tables, 55 refs.     

Review Section

Sokolov, V. A. , MIGRATION OF GAS AND OIL, Akademiya Nauk SSSR, Moscow, 1956. A Synopsis by Paul A. Witherspoon and W. D. Romey. ¹

Markovsky, A. P. , chief editor, GEOLOGIC STRUCTURE OF THE U. S. S. R.: volume I, Stratigraphy, edited by N. K. Ovechkin, 588 p. ; volume II, Magmatic Processes, edited by Yu. I. Polovinkina, 331 p. ; volume III, Tectonics, edited by L. I. Krasny, 384 p.¹ A review by Eugene A. Alexandrov. ²     

Review Section

ABSTRACT

The petrology, geochronology, and geochemistry of the early Permian volcanic rocks from Houtoumiao area, south Xiwuqi County in central Inner Mongolia of China, are studied to elucidate the early Permian tectonic setting of the region. The volcanic rocks, which are interbedded with sandstone, feature both mafic and felsic compositions and show a bimodal nature. Zircon U–Pb dating reveals that the volcanic rocks formed at 274–278 Ma, similar to the ages of bimodal magmatism in neighbouring areas. The mafic rocks are composed of tholeiitic basalt, basaltic andesite, basaltic trachyandesite, and trachyandesite. They are rich in Th, U, and LILEs, depleted in HFSEs Nb, Ta, and Ti, and have positive ε_Nd(t) values (+3.6 to +7.9). Geochemical analyses indicate that the mafic rocks originated from metasomatized lithospheric mantle. The felsic volcanic rocks are mainly rhyolite, with minor trachyte and dacite. They have different evolutionary tendencies of major elements, chondrite-normalized REE patterns, and isotopic compositions from the mafic volcanic rocks, which preclude formation by fractional crystallization of mafic melts. The ε_Nd(t) values of the felsic rocks are similar to those of the Carboniferous Baolidao arc rocks in the region. It is suggested that Permian felsic melts originated from the partial melting of Carboniferous juvenile arc-related rocks. By comparison with typical Cenozoic bimodal volcanism associated with several tectonic settings, including rift, post-collisional setting, back-arc basin, and the Basin and Range, USA, the bimodal volcanic rocks in central Inner Mongolia display similar petrological and geochemical characteristics to the rocks from back-arc basin and the Basin and Range, USA. Based on the analysis of regional geological data, it is inferred that the early Permian bimodal volcanic rocks in the study area formed on an extensional continental margin of the Siberian palaeoplate after late Carboniferous subduction–accretion.     

Review Section

Current Dlgest of the Soviet Press, DIAMOND DEPOSITS IN YAKUTIA AWAIT DEVELOPMENT. A condensation and translation of an article by K. Kondakov and G. Naumov in Voprosy ekonomiki, no. 6, pp. 135–140. Reprinted with perrniss~on of copyright holder, Current Digest of the Soviet Press, v. 9, no. 37, published at Columbia University by the Joint Committee on Slavic Studies, New York.     

Review Section

Belousov, V. V., FUNDAMENTAL PROBLEMS OF TECTONICS¹, The State Geology and Conservation Publishing House, Moscow, 1954, 606 pp. A Review by Mark Burgunker.

Nalivkin, D. V., A STUDY OF FACIES: THE ENVIRONMENT OF DEPOSITION ¹, The Department of Geologic-Geographic Sciences, the Academy of Science of the USSR. Moscow and Leningrad, 1956, vol. I, 534 pp.; vol. II, 393 pp. A Review by Mark Burgunker.

Strakhov, N. M. , Brodskaya, N. G. , Knyaseva, L. M., Razzhivina, A. N., Rateev, M. A., Sapozhnikiv, D. G., and E. S. Shishova. , FORMATION OF SEDIMENTS IN RECENT BASINS: A symposium, Moscow 1954. 791 pp. A review by George V. Chilingar, University of Southern California¹.     

Review Section

Yakzhin, A. A., RELATIONSHIPS IN FORMATION AND DISTRIBUTION OF FLUORITE DEPOSITS IN ZABAYKAL'YA, Gosgeoltekhizdat, Moscow, 1962.¹ 250 pp; 78 figs (tectonic map of the territory), 25 tables, references. (NK 62-24(54)).² A review by V. P. Sokoloff.

FOLDED DEFORMATIONS IN THE EARTH'S CRUST, THEIR TYPES, AND THE MECHANISMS OF THEIR DEVELOPMENT, Collected Papers, The O. Yu. Shmidt Memorial Institute of Earth's Physics, Moscow, 1962.¹ 335 pp; 16 articles, 143 figs. (including 25 photographs), 6 tables, references. (K 488).² A review by V. P. Sokoloff.

PROBLEMS IN PETROGRAPHY AND MINERALOGY OF THE EASTERN PART OF THE SIBERIAN PLATFORM AND OF THE VERKHOYANSK-CHUKOTKA FOLDED REGION, Transactions of the Yakutian Branch of the Siberian Division, Academy of Sciences of the U.S.S.R., Collected Papers, no. 11, Moscow, 1962¹. 139 pp; 9 articles, 67 figs. (including 39 photographs), 25 tables, references (N1(62-24(39)).² A review by V. P. Sokoloff.

PHYSICAL METHODS IN RESEARCH ON SEDIMENTARY ROCKS AND MINERALS, Proceedings of the first All-Union Conference on Physical Methods in Research on Sedimentary Rocks and Minerals, Committee on Sedimentary Rocks at the Division of Geological and Geographical Sciences, Moscow, 1962.¹ 26 articles, 98 figs. (including 27 photographs), 33 tables, references. (K 503).² A review by V. P. Sokoloff.     

Review Section

THE GEOLOGY OF THE U. S. S. R. VOLUME XXII: THE TURKMEN SOVIET SOCIALIST REPUBLIC. PART I. GEOLOGICAL DESCRIPTION. Luppov, N. P., ed. , Sukocheva, M. P., and Neronova, L. V., assoc. ed: Ministry of Geology and Mineral Conservation, 658 P. , Moscow, 1957. A Review by Mark Burgunker.     

Review Section

Ornatsky, N. V., MEKHANIKA GRUNTOV (SOIL MECHANICS), Moscow University, 1950, 420 pp.     

Review Section

Nalivkin, D. V., BRIEF ESSAY ON THE GEOLOGY OF THE U. S. S. R. Gosgeoltekhizdat, Moscow 1957, 144 p. A review by Eugene A. Alexandrov, Columbia University.     

Review Section

Gubin, Igor' E. Zakonomernosti Seysmicheskikh proyavleniy na territorii Tadzhikistana (Geologiya i seysmichnost') [REGULARITIES OF SEISMIC PHENOMENA IN THE TERRITORY OF TADJIKISTAN (GEOLOGY AND SEISMICITY)]: Moscow, Akad. Nauk SSSR, 464 p., 1960. A Review by Anatol J. Shneiderov.

Nalivkin, Dimitri Vasil'evich, STUDY OF FACIES, GEOGRAPHIC CONDITIONS OF FORMATIONS OF SEDIMENTS¹, in two volumes, 1956. A Review by Siemon W. Muller, Stanford University.     

A Review on the Global Stratotype Section and Point of the Permian-Triassic Boundary

1 Introduction The Global Stratotype Section and Point (GSSP) of the Permian-Triassic Boundary (PTB) has been ratified by IUGS in 2001 (Yin et al., 2001). It is defined at the base of the Hindeodus parvus horizon, i.e. the base of Bed 27c of Meishan Section D, Changxing County, Zhejiang Province, South China. The PTB is important because it is not only an erathem boundary but also a great turning point of geological history symbolized by profound global changes and the strongest …     

Reference Section

Geological Papers in Recent Russian and East European Periodicals, Russian Serials

Geological Papers in Recent Russian and East European Periodicals, East European Serials

Recent Translation in Geology

Announcements from NOVYYE KNIGI and other Publications Lists

Translation in Geology Available from the AGI Translation Pool     

数字剖面系统在实测地层剖面中的应用及整理

实测剖面是地质工作的核心,各项地质工作的开展、理论分析研究、报告编写等都离不开剖面资料。因此,利用数字化剖面系统合理地进行计算和图件编制显得极为重要。