14 research outputs found
Bimodal Volcano-Plutonic Complexes in the Frame of Eastern Member of Mongol-Okhotsk Orogenic Belt, as a Proof of the Time of Final Closure of Mongol-Okhotsk Basin
THE ROLE OF MESOZOIC GEODYNAMIC EVENTS IN FORMATION OF SEDIMENTARY BASINS ON THE FRAMING OF THE EASTERN MONGOL-OKHOTSK OROGENIC BELT
The Mongol-Okhotsk orogenic belt, finally formed in the end of the Mesozoic as a result of later tectonic events, is divided into two flanks: western and eastern. Its formation is obviously due to a regular change in geodynamic events significantly obscured by late tectonic and magmatic processes in the western flank and more clearly defined in the eastern flank from both magmatic and stratified formations. The early changes in geodynamic environment are most clearly determined by the formation of magmatic complexes whose completion is usually accompanied by the strata formation. Stratons framing the eastern flank of the Mongol-Okhotsk orogenic belt in the Mesozoic were formed in sedimentary basins, which are currently isolated to the Krestovkinsky and Ogodzhinsky basins along the southern border and to the Strelkinsky, Malotyndinsky, Toromsky and Udsky basins along the northern border. The deposition environment varied from deep-sea marine to continental. The article attempts to correlate the cross-sections of sedimentary basins on the framing of the eastern Mongol-Okhotsk orogenic belt and considers similarity or difference in their structure, conditions of sedimentation, tectonic positions and dependence of their evolution on geodynamic processes in the regio
ΠΠΎΠ·Π΄Π½Π΅ΠΌΠ΅Π·ΠΎΠ·ΠΎΠΉΡΠΊΠΈΠ΅ Π°Π΄Π°ΠΊΠΈΡΠΎΠ²ΡΠ΅ Π³ΡΠ°Π½ΠΈΡΡ ΡΠΆΠ½ΠΎΠ³ΠΎ ΠΎΠ±ΡΠ°ΠΌΠ»Π΅Π½ΠΈΡ Π²ΠΎΡΡΠΎΡΠ½ΠΎΠ³ΠΎ Π·Π²Π΅Π½Π° ΠΠΎΠ½Π³ΠΎΠ»ΠΎ-ΠΡ ΠΎΡΡΠΊΠΎΠ³ΠΎ ΠΎΡΠΎΠ³Π΅Π½Π½ΠΎΠ³ΠΎ ΠΏΠΎΡΡΠ°: Π²Π΅ΡΠ΅ΡΡΠ²Π΅Π½Π½ΡΠΉ ΡΠΎΡΡΠ°Π², Π³Π΅ΠΎΠ΄ΠΈΠ½Π°ΠΌΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΡΡΠ»ΠΎΠ²ΠΈΡ ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½ΠΈΡ
Granitoids of the Magdagachi complex were studied using new and published petrochemical, geochemical and isotopic (Sm-Nd, Rb-Sr) data. Granitoid samples were taken from the southern frame of the eastern flank of the Mongol-Okhotsk orogenic belt (MOOB). Their analysis shows increased concentrations of Sr, Ba, Eu; reduced concentrations of Nb, Ta; abnormally low concentrations of HREE, Y and Yb; significant fractionation of REE; and high Sr/Y ratios. Therefore, the Magdagachi granitoids are "classical" adakites that may have formed at a depth of more than 45 km due to melting of eclogite with a garnet content of 20β50 %. Such conditions could exist under subduction as a result of melting of the frontal or lateral parts of the slab in subduction windows formed during oblique subduction at an orthogonal sinking angle. Highly metamorphosed lower crust Precambrian formations were also melted, and a source of parental melts could have been composed of both the mantle and crustal materials. Two tectonic scenarios are proposed that could have been accompanied by the formation of Magdagachi granitoids. Both scenarios refer to subduction processes, but differ in interactions between various regional structures in the Late Mesozoic.Β Π‘ΠΎΠ³Π»Π°ΡΠ½ΠΎ Π½ΠΎΠ²ΡΠΌ ΠΈ ΡΠΆΠ΅ ΠΎΠΏΡΠ±Π»ΠΈΠΊΠΎΠ²Π°Π½Π½ΡΠΌ ΠΏΠ΅ΡΡΠΎΡ
ΠΈΠΌΠΈΡΠ΅ΡΠΊΠΈΠΌ, Π³Π΅ΠΎΡ
ΠΈΠΌΠΈΡΠ΅ΡΠΊΠΈΠΌ ΠΈ ΠΈΠ·ΠΎΡΠΎΠΏΠ½ΡΠΌ (Sm-Nd, Rb-Sr) Π΄Π°Π½Π½ΡΠΌ, Π΄Π»Ρ Π³ΡΠ°Π½ΠΈΡΠΎΠΈΠ΄ΠΎΠ² ΠΌΠ°Π³Π΄Π°Π³Π°ΡΠΈΠ½ΡΠΊΠΎΠ³ΠΎ ΠΊΠΎΠΌΠΏΠ»Π΅ΠΊΡΠ° ΡΠΆΠ½ΠΎΠ³ΠΎ ΠΎΠ±ΡΠ°ΠΌΠ»Π΅Π½ΠΈΡ Π²ΠΎΡΡΠΎΡΠ½ΠΎΠ³ΠΎ Π·Π²Π΅Π½Π° ΠΠΎΠ½Π³ΠΎΠ»ΠΎ-ΠΡ
ΠΎΡΡΠΊΠΎΠ³ΠΎ ΠΎΡΠΎΠ³Π΅Π½Π½ΠΎΠ³ΠΎ ΠΏΠΎΡΡΠ° ΡΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΎ, ΡΡΠΎ ΠΎΠ½ΠΈ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΠ·ΡΡΡΡΡ ΠΏΠΎΠ²ΡΡΠ΅Π½Π½ΡΠΌΠΈ ΠΊΠΎΠ½ΡΠ΅Π½ΡΡΠ°ΡΠΈΡΠΌΠΈ Sr, Ba, Eu ΠΈ ΠΏΠΎΠ½ΠΈΠΆΠ΅Π½Π½ΡΠΌΠΈ ΡΠΎΠ΄Π΅ΡΠΆΠ°Π½ΠΈΡΠΌΠΈ Nb, Ta, Π°Π½ΠΎΠΌΠ°Π»ΡΠ½ΠΎ Π½ΠΈΠ·ΠΊΠΈΠΌΠΈ ΠΊΠΎΠ½ΡΠ΅Π½ΡΡΠ°ΡΠΈΡΠΌΠΈ HREE, Y ΠΈ Yb; Π·Π½Π°ΡΠΈΡΠ΅Π»ΡΠ½ΡΠΌ ΡΡΠ°ΠΊΡΠΈΠΎΠ½ΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ ΡΠ΅Π΄ΠΊΠΎΠ·Π΅ΠΌΠ΅Π»ΡΠ½ΡΡ
ΡΠ»Π΅ΠΌΠ΅Π½ΡΠΎΠ²; Π²ΡΡΠΎΠΊΠΈΠΌΠΈ ΡΠΎΠΎΡΠ½ΠΎΡΠ΅Π½ΠΈΡΠΌΠΈ Sr/Y. ΠΡΠΈ Π΄Π°Π½Π½ΡΠ΅ Π³ΠΎΠ²ΠΎΡΡΡ ΠΎ ΠΏΡΠΈΠ½Π°Π΄Π»Π΅ΠΆΠ½ΠΎΡΡΠΈ ΠΏΠΎΡΠΎΠ΄ ΠΊΠΎΠΌΠΏΠ»Π΅ΠΊΡΠ° ΠΊ Β«ΠΊΠ»Π°ΡΡΠΈΡΠ΅ΡΠΊΠΈΠΌΒ» Π°Π΄Π°ΠΊΠΈΡΠ°ΠΌ. ΠΡΠ΅Π΄ΠΏΠΎΠ»Π°Π³Π°Π΅ΡΡΡ, ΡΡΠΎ ΠΎΠ½ΠΈ ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π»ΠΈΡΡ Π½Π° Π³Π»ΡΠ±ΠΈΠ½Π΅ Π±ΠΎΠ»Π΅Π΅ 45 ΠΊΠΌ Π·Π° ΡΡΠ΅Ρ ΠΏΠ»Π°Π²Π»Π΅Π½ΠΈΡ ΡΠΊΠ»ΠΎΠ³ΠΈΡΠ° Ρ ΡΠΎΠ΄Π΅ΡΠΆΠ°Π½ΠΈΠ΅ΠΌ Π³ΡΠ°Π½Π°ΡΠ° 20β50 %. Π’Π°ΠΊΠΈΠ΅ ΡΡΠ»ΠΎΠ²ΠΈΡ ΠΌΠΎΠ³Π»ΠΈ ΡΡΡΠ΅ΡΡΠ²ΠΎΠ²Π°ΡΡ Π² ΠΎΠ±ΡΡΠ°Π½ΠΎΠ²ΠΊΠ΅ ΡΡΠ±Π΄ΡΠΊΡΠΈΠΈ Π² ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠ΅ ΠΏΠ»Π°Π²Π»Π΅Π½ΠΈΡ ΡΡΠΎΠ½ΡΠ°Π»ΡΠ½ΠΎΠΉ ΡΠΎΡΡΠ°Π²Π»ΡΡΡΠ΅ΠΉ ΠΈΠ»ΠΈ Π±ΠΎΠΊΠΎΠ²ΡΡ
ΡΠ°ΡΡΠ΅ΠΉ ΡΠ»ΡΠ±Π° Π² ΡΡΠ±Π΄ΡΠΊΡΠΈΠΎΠ½Π½ΡΡ
ΠΎΠΊΠ½Π°Ρ
, ΠΎΠ±ΡΠ°Π·ΡΡΡΠΈΡ
ΡΡ ΠΏΡΠΈ ΠΊΠΎΡΠΎΠΉ ΡΡΠ±Π΄ΡΠΊΡΠΈΠΈ ΠΈ ΠΎΡΡΠΎΠ³ΠΎΠ½Π°Π»ΡΠ½ΠΎΠΌ ΡΠ³Π»Π΅ ΠΏΠΎΠ³ΡΡΠΆΠ΅Π½ΠΈΡ. ΠΡΠΈ ΡΡΠΎΠΌ ΠΏΠ»Π°Π²Π»Π΅Π½ΠΈΡ ΠΏΠΎΠ΄Π²Π΅ΡΠ³Π°Π»ΠΈΡΡ ΡΠ°ΠΊΠΆΠ΅ Π²ΡΡΠΎΠΊΠΎΠΌΠ΅ΡΠ°ΠΌΠΎΡΡΠΈΠ·ΠΎΠ²Π°Π½Π½ΡΠ΅ Π½ΠΈΠΆΠ½Π΅ΠΊΠΎΡΠΎΠ²ΡΠ΅ Π΄ΠΎΠΊΠ΅ΠΌΠ±ΡΠΈΠΉΡΠΊΠΈΠ΅ ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½ΠΈΡ, Π° Π² ΡΠΎΡΡΠ°Π²Π΅ ΠΈΡΡΠΎΡΠ½ΠΈΠΊΠ° ΡΠΎΠ΄ΠΎΠ½Π°ΡΠ°Π»ΡΠ½ΡΡ
ΡΠ°ΡΠΏΠ»Π°Π²ΠΎΠ² ΠΏΡΠΈΠ½ΠΈΠΌΠ°Π»ΠΎ ΡΡΠ°ΡΡΠΈΠ΅ ΠΊΠ°ΠΊ ΠΌΠ°Π½ΡΠΈΠΉΠ½ΠΎΠ΅, ΡΠ°ΠΊ ΠΈ ΠΊΠΎΡΠΎΠ²ΠΎΠ΅ Π²Π΅ΡΠ΅ΡΡΠ²ΠΎ. ΠΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½ΠΎ Π΄Π²Π° ΡΠ΅ΠΊΡΠΎΠ½ΠΈΡΠ΅ΡΠΊΠΈΡ
ΡΡΠ΅Π½Π°ΡΠΈΡ, ΠΊΠΎΡΠΎΡΡΠ΅ ΠΌΠΎΠ³Π»ΠΈ ΡΠΎΠΏΡΠΎΠ²ΠΎΠΆΠ΄Π°ΡΡΡΡ ΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΈΠ΅ΠΌ Π³ΡΠ°Π½ΠΈΡΠΎΠΈΠ΄ΠΎΠ² ΠΌΠ°Π³Π΄Π°Π³Π°ΡΠΈΠ½ΡΠΊΠΎΠ³ΠΎ ΠΊΠΎΠΌΠΏΠ»Π΅ΠΊΡΠ°. ΠΠ±Π° ΡΡΠ΅Π½Π°ΡΠΈΡ ΡΠΎΠΎΡΠ²Π΅ΡΡΡΠ²ΡΡΡ ΡΡΠ»ΠΎΠ²ΠΈΡΠΌ ΡΡΠ±Π΄ΡΠΊΡΠΈΠΎΠ½Π½ΡΡ
ΠΏΡΠΎΡΠ΅ΡΡΠΎΠ², Π½ΠΎ ΠΎΡΠ»ΠΈΡΠ°ΡΡΡΡ Π²Π·Π°ΠΈΠΌΠΎΠ΄Π΅ΠΉΡΡΠ²ΠΈΠ΅ΠΌ ΡΠ°Π·Π»ΠΈΡΠ½ΡΡ
ΡΠ΅Π³ΠΈΠΎΠ½Π°Π»ΡΠ½ΡΡ
ΡΡΡΡΠΊΡΡΡ Π² ΠΏΠΎΠ·Π΄Π½Π΅ΠΌΠ΅Π·ΠΎΠ·ΠΎΠΉΡΠΊΠΎΠ΅ Π²ΡΠ΅ΠΌΡ.
Π ΠΠΠ¬ ΠΠΠΠΠΠΠΠ‘ΠΠΠ₯ ΠΠΠΠΠΠΠΠΠΠ§ΠΠ‘ΠΠΠ₯ Π‘ΠΠΠ«Π’ΠΠ Π Π€ΠΠ ΠΠΠ ΠΠΠΠΠΠ ΠΠ‘ΠΠΠΠ§ΠΠ«Π₯ ΠΠΠ‘Π‘ΠΠΠΠΠ ΠΠΠ ΠΠΠΠΠΠΠ― ΠΠΠ‘Π’ΠΠ§ΠΠΠΠ Π€ΠΠΠΠΠ ΠΠΠΠΠΠΠ-ΠΠ₯ΠΠ’Π‘ΠΠΠΠ ΠΠ ΠΠΠΠΠΠΠΠ ΠΠΠ―Π‘Π
The Mongol-Okhotsk orogenic belt, finally formed in the end of the Mesozoic as a result of later tectonic events, is divided into two flanks: western and eastern. Its formation is obviously due to a regular change in geodynamic events significantly obscured by late tectonic and magmatic processes in the western flank and more clearly defined in the eastern flank from both magmatic and stratified formations. The early changes in geodynamic environment are most clearly determined by the formation of magmatic complexes whose completion is usually accompanied by the strata formation. Stratons framing the eastern flank of the Mongol-Okhotsk orogenic belt in the Mesozoic were formed in sedimentary basins, which are currently isolated to the Krestovkinsky and Ogodzhinsky basins along the southern border and to the Strelkinsky, Malotyndinsky, Toromsky and Udsky basins along the northern border. The deposition environment varied from deep-sea marine to continental. The article attempts to correlate the cross-sections of sedimentary basins on the framing of the eastern Mongol-Okhotsk orogenic belt and considers similarity or difference in their structure, conditions of sedimentation, tectonic positions and dependence of their evolution on geodynamic processes in the regionΠΠΎΠ½Π³ΠΎΠ»ΠΎ-ΠΡ
ΠΎΡΡΠΊΠΈΠΉ ΠΎΡΠΎΠ³Π΅Π½Π½ΡΠΉ ΠΏΠΎΡΡ, ΠΎΠΊΠΎΠ½ΡΠ°ΡΠ΅Π»ΡΠ½ΠΎ ΡΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π²ΡΠΈΠΉΡΡ Π² ΠΊΠΎΠ½ΡΠ΅ ΠΌΠ΅Π·ΠΎΠ·ΠΎΡ, Π² ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠ΅ Π±ΠΎΠ»Π΅Π΅ ΠΏΠΎΠ·Π΄Π½ΠΈΡ
ΡΠ΅ΠΊΡΠΎΠ½ΠΈΡΠ΅ΡΠΊΠΈΡ
ΡΠΎΠ±ΡΡΠΈΠΉ Π±ΡΠ» ΡΠ°Π·Π΄Π΅Π»Π΅Π½ Π½Π° Π΄Π²Π° ΡΠ»Π°Π½Π³Π°: Π·Π°ΠΏΠ°Π΄Π½ΡΠΉ ΠΈ Π²ΠΎΡΡΠΎΡΠ½ΡΠΉ. Π Π΅Π³ΠΎ ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½ΠΈΠΈ ΠΏΡΠΎΡΠ»Π΅ΠΆΠΈΠ²Π°Π΅ΡΡΡ Π·Π°ΠΊΠΎΠ½ΠΎΠΌΠ΅ΡΠ½ΠΎΠ΅ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ Π³Π΅ΠΎΠ΄ΠΈΠ½Π°ΠΌΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΏΡΠΎΡΠ΅ΡΡΠΎΠ², ΠΊΠΎΡΠΎΡΡΠ΅ Π² ΠΏΡΠ΅Π΄Π΅Π»Π°Ρ
Π·Π°ΠΏΠ°Π΄Π½ΠΎΠ³ΠΎ ΡΠ»Π°Π½Π³Π° Π·Π½Π°ΡΠΈΡΠ΅Π»ΡΠ½ΠΎ Β«Π·Π°ΡΡΡΠ΅Π²Π°Π½ΡΒ» ΠΏΠΎΠ·Π΄Π½ΠΈΠΌΠΈ ΡΠ΅ΠΊΡΠΎΠ½ΠΈΡΠ΅ΡΠΊΠΈΠΌΠΈ ΠΈ ΠΌΠ°Π³ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΠΌΠΈ ΡΠΎΠ±ΡΡΠΈΡΠΌΠΈ, ΡΠΎΠ³Π΄Π° ΠΊΠ°ΠΊ Π² ΠΏΡΠ΅Π΄Π΅Π»Π°Ρ
Π²ΠΎΡΡΠΎΡΠ½ΠΎΠ³ΠΎ ΡΠ»Π°Π½Π³Π° ΡΡΠΈ ΠΏΡΠΎΡΠ΅ΡΡΡ ΠΌΠ΅Π½Π΅Π΅ ΠΈΡΠΊΠ°ΠΆΠ΅Π½Ρ ΠΈ ΡΠΈΠΊΡΠΈΡΡΡΡΡΡ ΠΏΠΎ Π½Π°Π»ΠΈΡΠΈΡ ΠΊΠ°ΠΊ ΠΌΠ°Π³ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΡ
, ΡΠ°ΠΊ ΠΈ ΡΡΡΠ°ΡΠΈΡΠΈΡΠΈΡΠΎΠ²Π°Π½Π½ΡΡ
ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½ΠΈΠΉ. ΠΠ°ΡΠ°Π»ΠΎ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ Π³Π΅ΠΎΠ΄ΠΈΠ½Π°ΠΌΠΈΡΠ΅ΡΠΊΠΈΡ
ΡΡΠ»ΠΎΠ²ΠΈΠΉ Π½Π°ΠΈΠ±ΠΎΠ»Π΅Π΅ ΡΠ΅ΡΠΊΠΎ ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΠ΅ΡΡΡ ΠΏΠΎ ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΠΌΠ°Π³ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΊΠΎΠΌΠΏΠ»Π΅ΠΊΡΠΎΠ², Π° ΠΈΡ
Π·Π°Π²Π΅ΡΡΠ΅Π½ΠΈΠ΅, ΠΊΠ°ΠΊ ΠΏΡΠ°Π²ΠΈΠ»ΠΎ, ΡΠΎΠΏΡΠΎΠ²ΠΎΠΆΠ΄Π°Π΅ΡΡΡ ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ ΡΡΡΠ°ΡΠΎΠ½ΠΎΠ². Π‘ΡΡΠ°ΡΠΎΠ½Ρ Π² ΠΎΠ±ΡΠ°ΠΌΠ»Π΅Π½ΠΈΠΈ Π²ΠΎΡΡΠΎΡΠ½ΠΎΠ³ΠΎ ΡΠ»Π°Π½Π³Π° ΠΠΎΠ½Π³ΠΎΠ»ΠΎ-ΠΡ
ΠΎΡΡΠΊΠΎΠ³ΠΎ ΠΎΡΠΎΠ³Π΅Π½Π½ΠΎΠ³ΠΎ ΠΏΠΎΡΡΠ° Π² ΠΌΠ΅Π·ΠΎΠ·ΠΎΠ΅ ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π»ΠΈΡΡ Π² ΠΎΡΠ°Π΄ΠΎΡΠ½ΡΡ
Π±Π°ΡΡΠ΅ΠΉΠ½Π°Ρ
, ΡΡΠ°Π³ΠΌΠ΅Π½ΡΡ ΠΊΠΎΡΠΎΡΡΡ
Π² Π½Π°ΡΡΠΎΡΡΠ΅Π΅ Π²ΡΠ΅ΠΌΡ ΠΎΠ±ΠΎΡΠΎΠ±Π»Π΅Π½Ρ Π²Π΄ΠΎΠ»Ρ ΡΠΆΠ½ΠΎΠΉ Π³ΡΠ°Π½ΠΈΡΡ Π² ΠΡΠ΅ΡΡΠΎΠ²ΠΊΠΈΠ½ΡΠΊΠΈΠΉ ΠΈ ΠΠ³ΠΎΠ΄ΠΆΠΈΠ½ΡΠΊΠΈΠΉ Π±Π°ΡΡΠ΅ΠΉΠ½Ρ, Π° Π²Π΄ΠΎΠ»Ρ ΡΠ΅Π²Π΅ΡΠ½ΠΎΠΉ β Π² Π‘ΡΡΠ΅Π»ΠΊΠΈΠ½ΡΠΊΠΈΠΉ, ΠΠ°Π»ΠΎΡΡΠ½Π΄ΠΈΠ½ΡΠΊΠΈΠΉ, Π’ΠΎΡΠΎΠΌΡΠΊΠΈΠΉ ΠΈ Π£Π΄ΡΠΊΠΈΠΉ Π±Π°ΡΡΠ΅ΠΉΠ½Ρ. ΠΠ°ΠΊΠΎΠΏΠ»Π΅Π½ΠΈΠ΅ ΠΎΡΠ°Π΄ΠΊΠΎΠ² ΠΏΡΠΎΠΈΡΡ
ΠΎΠ΄ΠΈΠ»ΠΎ Π² ΡΠ°Π·Π»ΠΈΡΠ½ΡΡ
ΡΡΠ»ΠΎΠ²ΠΈΡΡ
: ΠΎΡ Π³Π»ΡΠ±ΠΎΠΊΠΎΠ²ΠΎΠ΄Π½ΡΡ
ΠΌΠΎΡΡΠΊΠΈΡ
Π΄ΠΎ ΠΊΠΎΠ½ΡΠΈΠ½Π΅Π½ΡΠ°Π»ΡΠ½ΡΡ
. Π ΡΡΠ°ΡΡΠ΅ Π²ΡΠΏΠΎΠ»Π½Π΅Π½Π° ΠΊΠΎΡΡΠ΅Π»ΡΡΠΈΡ ΡΠ°Π·ΡΠ΅Π·ΠΎΠ² ΠΎΡΠ°Π΄ΠΎΡΠ½ΡΡ
Π±Π°ΡΡΠ΅ΠΉΠ½ΠΎΠ² Π² ΠΎΠ±ΡΠ°ΠΌΠ»Π΅Π½ΠΈΠΈ Π²ΠΎΡΡΠΎΡΠ½ΠΎΠ³ΠΎ ΡΠ»Π°Π½Π³Π° ΠΠΎΠ½Π³ΠΎΠ»ΠΎ-ΠΡ
ΠΎΡΡΠΊΠΎΠ³ΠΎ ΠΎΡΠΎΠ³Π΅Π½Π½ΠΎΠ³ΠΎ ΠΏΠΎΡΡΠ°; ΡΠ°ΡΡΠΌΠ°ΡΡΠΈΠ²Π°Π΅ΡΡΡ ΡΡ
ΠΎΠ΄ΡΡΠ²ΠΎ ΠΈΠ»ΠΈ ΡΠ°Π·Π»ΠΈΡΠΈΠ΅ ΡΠΎΡΡΠ°Π²ΠΎΠ², Π²ΠΎΠ·ΡΠ°ΡΡΠ°, ΡΡΠ»ΠΎΠ²ΠΈΠΉ ΠΎΡΠ°Π΄ΠΊΠΎΠ½Π°ΠΊΠΎΠΏΠ»Π΅Π½ΠΈΡ, ΡΠ΅ΠΊΡΠΎΠ½ΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΏΠΎΠ·ΠΈΡΠΈΠΉ ΠΈ Π·Π°Π²ΠΈΡΠΈΠΌΠΎΡΡΡ ΠΈΡ
ΡΠ²ΠΎΠ»ΡΡΠΈΠΈ ΠΎΡ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ Π³Π΅ΠΎΠ΄ΠΈΠ½Π°ΠΌΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΏΡΠΎΡΠ΅ΡΡΠΎΠ² Π² ΡΠ΅Π³ΠΈΠΎΠ½Π΅
Late Mesozoic adakite granites of the southern frame of the eastern flank of the Mongol-Okhotsk orogenic belt: material composition and geodynamic conditions of formation
Granitoids of the Magdagachi complex were studied using new and published petrochemical, geochemical and isotopic (Sm-Nd, Rb-Sr) data. Granitoid samples were taken from the southern frame of the eastern flank of the Mongol-Okhotsk orogenic belt (MOOB). Their analysis shows increased concentrations of Sr, Ba, Eu; reduced concentrations of Nb, Ta; abnormally low concentrations of HREE, Y and Yb; significant fractionation of REE; and high Sr/Y ratios. Therefore, the Magdagachi granitoids are "classical" adakites that may have formed at a depth of more than 45 km due to melting of eclogite with a garnet content of 20β50 %. Such conditions could exist under subduction as a result of melting of the frontal or lateral parts of the slab in subduction windows formed during oblique subduction at an orthogonal sinking angle. Highly metamorphosed lower crust Precambrian formations were also melted, and a source of parental melts could have been composed of both the mantle and crustal materials. Two tectonic scenarios are proposed that could have been accompanied by the formation of Magdagachi granitoids. Both scenarios refer to subduction processes, but differ in interactions between various regional structures in the Late Mesozoic
Secure and Efficient Matrix Multiplication with MapReduce
International audienceMapReduce is one of the most popular distributed programming paradigms that allows processing big data sets in parallel on a cluster. MapReduce users often outsource data and computations to a public cloud, which yields inherent security concerns. In this paper, we consider the problem of matrix multiplication and one of the most efficient matrix multiplication algorithms: the Strassen-Winograd (SW) algorithm. Our first contribution is a distributed MapReduce algorithm based on SW. Then, we tackle the security concerns that occur when outsourcing matrix multiplication computation to a honest-but-curious cloud i.e., that executes tasks dutifully, but tries to learn as much information as possible. Our main contribution is a secure distributed MapReduce algorithm called S2M3 (Secure Strassen-Winograd Matrix Multiplication with MapReduce) that enjoys security guarantees such as: none of the cloud nodes can learn the input or the output data. We formally prove the security properties of S2M3 and we present an empirical evaluation devoted to show its efficiency