Neogene strike-slip faulting in Sakhalin and the Japan Sea opening Marc Fournier, Laurent Jolivet, Philippe Huchon, Konstantin F. Sergeyev, Leonid Oscorbin To cite this version: Marc Fournier, Laurent Jolivet, Philippe Huchon, Konstantin F. Sergeyev, Leonid Oscorbin. Neo- gene strike-slip faulting in Sakhalin and the Japan Sea opening. Journal of Geophysical Research : Solid Earth, American Geophysical Union, 1994, 99 (B2), pp.2701-2725. 10.1029/93JB02026. insu- 00726734 HAL Id: insu-00726734 https://hal-insu.archives-ouvertes.fr/insu-00726734 Submitted on 31 Aug 2012 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 99, NO. B2, PAGES 2701-2725, FEBRUARY 10, 1994 Neogenestrike-slip faulting in Sakhalin and the Japan Sea opening Marc Fournier, Laurent Jolivet, and Philippe Huchon Laboratoirede G•.ologie,Drpartement Terre AtmosphereOcean, Ecole Normale Sul•rieure, Paris KonstantinF. Sergeyevand Leonid S. Oscorbin Instituteof Marine Geologyand Geophysics, Far EastScience Center, Yuzhno-Sakhalinsk, Russia We describestructural data from a 2000 km N-S dextral strike-slip zone extending from northem Sakhalin to the southeastcomer of the JapanSea. Satellite images,field data, and focal mechanismsof earthquakesin Sakhalinare includedin the interpretation.Since Miocene time the deformationin Sakhalin hasbeen taken up by N-S dextralstrike-slip faults with a reversecomponent and associateden 6chelonfolds. Narrow en 6chelonNeogene basins were formed along strike-slipfaults and were later folded in a second stageof deformation.We proposea modelof basinformation along extensional faults delimitatingdominos betweentwo major strike-slipfaults, and subsequentcounterclockwise rotation of the dominosin a dextral transpressionalregime, basins becoming progressivelyoblique to the direction of maximum horizontal cmnpressionand undergoingshortening. The associationof bothdextral and compressionalfocal mechanisms of earthquakesindicates that the sametranspressional regime still prevailstoday in Sakhalin.We presentfault set measurements undertaken in Noto Peninsula and Yatsuo Basin at the southern end of the Sakhalin-East JapanSea strike-slipzone. Early and middle Miocene formationsrecorded the sametranstensional regime as observedalong the west coastof NE Honshu.During the early and middle Miocene the strike-slip regime wastranspressional to the northin Sakhalinand Hokkaido,and transtensional to the southalong the westcoast of NE Honshuas far as Noto Peninsulaand Yatsuobasin. Dextral motion accommodated the openingof the JapanSea as a pull-apartbasin, with the Tsushimafault to the west.The openingof the JapanSea ceasedat the end of the middle Miocene when transtensionstarted to changeto E-W compressionin the Japan arc. Subductionof the JapanSea lithosphereunder the Japanarc started1.8 Ma ago. The evolutionof the stress regime from transtensionalto compressionalin the southernpart of the strike-slip zone is related to the inceptionof the subductionof the youngPhilippine Sea Plate lithosphereunder the Japanarc duringthe late Miocene. Subductionrelated extensionis a necessarycondition for the opening of the Japan Sea. Two possiblemechanisms can accountfor dextral shearin this area: (1) counterclockwiserotation of crustal blocksdue to the collisionof India with Asia, (2) extrusionof the OkhotskSea block squeezedbetween the North America and Eurasiaplates. INTRODUCTION youngest dredged basaltic volcanics were dated 11 Ma [Kaneoka et al., 1990]. These agesare in good agreementwith Deformation resulting from the India-Asia collision is an earlier determination of the age of Japan Sea basement taken up by crustalthickening in the Himalaya-Tibet collision based on geophysicaldata betweev 30 and 10 Ma [Tamaki, zone and by geometric reorganization of continental blocks 1986, 1988]. Similar average heat flow value and basement accommodated by strike-slip motion along major faults depth in both Japan and Kuril Basins led Tamaki [1988] to [Molnar and Tapponnier, 1975; Tapponnier and Molnar, conclude to a simultaneousopening of the two basins in the 1976; Zonenshain and Savostin, 1981; Cobbold and Davy, late Oligocene to middle Miocene. Otsuki and Ehiro [1978] 1988; England and Molnar, 1990; Holt et al., 1991]. Along first outlined the role of strike-slip faults in the openingof the the southeasternlimit of Asia, strike-slip faults accommodated Japan Sea and proposed a drawerlike model of opening the opening of two marginal basins: the Andaman Sea in the between the left-lateral Tanakura tectonic line (TI'L) to the east prolongation of the Sagaing fault and Shan scarp system and the right-lateralTsushima fault (TF) to the west. Kimura et [Curray et al., 1979; Tapponnier et al., 1986], and possibly al. [1983] and Jolivet and Miyashita [1985] describedonland the SouthChina Sea along the extensionof the Red River fault transpressional deformation associated with N-S dextral [Tapponnier et al., 1982, 1986; Briais et al., 1993]. strike-slip motion in Sakhalin and Hokkaido during the In northeast Asia, at the end of the Tien Shan-Baikal- Oligocene and Miocene. Lallemant and Jolivet [1985] Stanovoy deformation zone, the Japan and Okhotsk Seas proposed a model of opening of the Japan Sea as a simple (Figure 1) openedin the Early and Middle Miocene. The oldest dextral pull-apart basin between this strike-slip zone to the oceanicbasalts drilled on the easternmargin of the JapanSea east, and the Tsushima fault to the west. Jolivet et al. [1991], during Ocean Drilling Program leg 127 have a radiometric using analogue laboratory modelling, refined the pull-apart 40Ar-39Arage of 24 Ma [Tamakiet al., 1992]and the model by introducing blocks rotations in the dextral shear zone, that only partly fit the paleomagnetic data. Jolivet [1986] associatedthe dextral motion to southward extrusion of the Okhotsk Sea block squeezedbetween the North America Copyright1994 by the AmericanGeophysical Union. and the Eurasiaplates. Kimura and Tamaki [1986] and Jolivet et al. [1990] finally related the opening of the Japan and Paper number 93JB02026. Okhotsk Seas to the motions of Asian microplates as a 0148-0227/94/93JB-02026505.00 consequenceof the India-Asia collision. 2701 2702 FOURNIERET AL.: NEOGENEDEXTRAL MOTION IN SAKHALINAND JAPAN SEA • OCEANICBASEMENT EURASIAI RECENT OFF-SHORE PLATE E-W COMPRESSION ZONE OKHOTSK KURIL BASIN ::JAPAN SEA-! /PACIFIC PLATE Fig. 1. Simplifiedstructural map of far eastAsia with topographyand bathymetry. Solid arrowsgive directionsof motionsof Pacificand Okhotsk plates relative to Asia.B is basin,IP is Izu Peninsula,MTL is mediantectonic line, R is ridge,S is strait,T is trench,TF is Tsushimafault, TI'L is Tanakuratectonic line, Y F is Yangsanfault, and ZR is Zenisu ridge. The easternguide of the JapanSea dextral pull-apartis a describedby Lallemant and Jolivet [ 1985], Jolivet and Huchon 2000-km-long strike-slip zone extending from the northern [1989] and Jolivet et al. [1991]. In Sakhalin, field studies end of Sakhalin island to the north, to the southeast comer of showed that the island is cut by a N-S trending faults system the Japan Sea to the south (Figure 2)[Kimura et al., 1983; [Zanyukov, 1971; Rozhdestvensky, 1982] which is Lallemant and Jolivet, 1985]. The central part of the strike- responsiblefor the intense shallow seismicity of the island slip zone from Hokkaido to the west coast of NE Honshu is [e.g., Oskorbin, 1977; Savostinet al., 1983; Tarakamov and FOURNIER ET AL.: NEOGENE DEXTRAL MOTION IN SAKHALIN AND JAPAN SEA 2703 Kim, 1983]. Field observationsby Rozhdestvensky [1982] 1400 1450 55 øm describeddextral Miocene strike-slip motion along the faults. In this paper we describeboth the north and the south endsof the strike-slip zone, respectively, in Sakhalin and Central Japan. We first presenta study of the strike-slipzone in Sakhalin based on the structural interpretation of Landsat images, results of field work in 1989 and 1990 along the Tym- Poronayskfault and in the East Sakhalin Mountains, and fault plane solutionsfor major earthquakessince 1960 [this study; Fukao and Furumoto, 1975; Dziewonski et al., 1985; 1987]. We confirm the conclusionsof Rozhdestvensky [1982]: the island is a right-lateral strike-slip zone of Neogene age. Dextral motion is inferred from large-scale geological structuresobserved on the satellite images. Small-scale fault measurements in Neogene deposits provide maximal horizontal stress directions compatible with the dextral motion along the N-S faults. Seismologicaldata show that the dextral motion is still active today. We proposea model of progressive strike-slip deformation with block rotations about vertical axes to explain the later shortening of the Neogene dextral en 6chelonbasins. In a secondpart we infer the Miocene paleostress field from fault measurements undertakenin Noto peninsula and Yatsuo basin (central Japan, Figure 1) at the southernextremity of the Sakhalin-EastJapan Sea strike-slip zone. Miocene formations recorded there the same transtensionaldeformation as observed