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Uphill-facing scarps develop in the central Swiss Alps, particularly along the Upper Rhone valley, the Urseren valley, the Upper Rhine valley, and Bedretto valley. It has been argued whether they have gravitational origin, tectonic origin, or differential uplift after the deglaciation. We made geological survey and topographic interpretation in the Bedretto valley, in which the Ticino River flows from the west-southwest to east-northeast. The Bedretto valley slopes have shoulders on both sides of the valley at elevations of 1500 to 1900 m, below which is a lower U-shaped valley. Uphill-facing scarps develop more on the southern side slopes of the Bedretto valley, where is underlain mainly by mica schist of the Bedretto zone, than on the northern side slopes, where is underlain mainly by gneiss and slate. In addition, they develop much more on slopes higher than the slope shoulders, and the uphill-facing scarps on the lower U-shaped valley are much smaller in scale. Tributary valleys on the south side of the Bedretto valley go down into this lower U-shaped valley from the southeast with intervening ridges, and we surveyed along the valleys of Ri di Cristallina, Ri di Valleggio, and Val Cavagnolo. We found that steeply-dipping schistosity in the ridges is toppled valleyward with brittle fractures along the hinge zones, which are approximately along or slightly higher than the tributary valley bottom. Rock mass as thick as 300 m thus toppled. Flexural toppling of mica schist developed uphill-facing scarps, which were mostly along high-angle faults, some of which were recognized to have brittle crush zones. The flexural toppling generated extension field in the upper ridges, where rock mass apparently settled down along normal faults. The reason why the northern side slopes of the Bedretto valley have much smaller uphill facing scarps may be due to the rocks are mainly gneiss and also due to the numbers of faults are possibly much less than in the southern slopes . The facts that uphill facing scarps are mainly developed above the lower U-shaped valleys may be related to the longer time intervals of the exposure of slopes higher than the slope breaks to the atmosphere during the glacial age.

Individuals with knee osteoarthritis (OA) show various dynamic sagittal-plane changes during the early stance phase of gait. However, the effect of these kinematic alterations on knee load during the early stance remains poorly understood.The purpose of this study was to examine the effect of altered sagittal- plane knee kinematics on knee load during the early stance.A total of 13 healthy adult men underwent gait analysis trials using four conditions (baseline and three altered conditions). The three altered conditions were defined as follows: 1) Less flexion (LF): a gait that decreased knee flexion excursion (KFE) owing to a reduced peak knee flexion angle compared to baseline. 2) Initial flexion (IF): a gait with decreased KFE owing to an increased knee flexion angle at initial contact, during which the peak knee flexion angle did not differ from baseline. 3) Flexion gait (FG): a gait that increased the knee flexion angle at initial contact but did not reduce KFE compared with the baseline. Data analyzed included peak external knee flexion moment (KFM), KFM impulse (impulse was an integral value from initial contact to peak value), peak vertical ground reaction force (VGRF), and maximum loading rate.Both LF and IF conditions significantly decreased peak VGRF (p 0.05) compared with the baseline. Peak KFM decreased in the LF condition and increased in the FG condition versus baseline (p 0.05). A significantly increased KFM impulse was found in both IF and FG conditions when compared with baseline (p 0.05).An increase in knee flexion angle during early stance increased knee loading. Interventions are likely required for improving excessive knee flexion during early stance phase of gait in individuals with knee OA.

Earthquakes are considered to be important triggers of deep-seated gravitational slope deformation (DGSD) in seismically active regions, and if that is the case, DGSD features could be candidates for off-fault paleoseismology investigations. On the basis of pit excavations and sediment cores at an off-fault DGSD site and a trench excavation across the active Neodani fault at a nearby site, we examined the records of DGSD and surface-rupturing paleoearthquakes of the Neodani fault. The four most recent DGSD events were dated at after 240 cal BP, 1710–340 cal BP, 4730–3970 cal BP, and 5570–5340 cal BP. The four most recent surface-rupturing earthquakes were dated at 1891 CE (the Nobi earthquake), 2010–1220 cal BP, 7180–2110 cal BP, and before 9540 cal BP. We conclude that the ages of the four DGSD events are consistent with surface-rupturing earthquakes on the adjacent Neodani fault. We infer that static crustal strain from repeated seismogenic faulting plays an important role in the occurrence of DGSD events, at least in the immediate vicinity of active faults, although coseismic severe shaking would have at least some effect on them. Our case study suggests that off-fault DGSDs can be used to reconstruct or refine the paleoseismic history of a nearby active fault. We propose that an ideal DGSD for that purpose would be located in an area of concentrated strain near a termination, bend, or stepover of the target fault.

We present a new approach for recognizing the origin of accreted basaltic rocks based on ocean plate stratigraphy (OPS), and on the petrology and geochemistry of basalts from mid-oceanic ridges (MORB) and oceanic islands (OIB) using examples from four accretionary complexes (AC) in SW Japan: Akiyoshi, Mino–Tamba, Chichibu and Shimanto. The key to the problem is the model of OPS, which includes an association of igneous and sedimentary rocks that form on an oceanic plate during its travel from a mid-oceanic ridge to a subduction zone. We propose the reconstruction of the tectonic settings of basalts according to their relationships with associated OPS sediments, their petrogenesis and their geochemical features. Five types of OPS are recognized in the accretionary complexes of SW Japan: (1) sandstone/shale; (2) sandstone/shale and chert; (3) sandstone/shale, chert and MORB; (4) sandstone/shale, chert, MORB and gabbro (± peridotite); (5) seamount OPS including OIB, cap carbonates, slope clastics and basal shale/chert. The alkaline, tholeiitic or calc-alkaline composition of basaltic melts, which are typical of oceanic islands, mid-oceanic ridges and island-arcs, respectively, can be identified by the sequence in crystallization of their major phenocrysts, i.e. olivine (ol), clinopyroxene (cpx) and plagioclase (pl), and by their compositions. Alkaline and calc-alkaline mafic lavas are characterized by an ol → cpx → pl succession, whereas tholeiitic melts by their ol → pl ± cpx succession. Titanium-rich minerals, e.g., Ti–augite, kaersutite, Ti–biotite, are typical of alkaline lavas. The application of geochemistry-based tectonic discrimination diagrams is also a powerful tool, if not supported by geological and petrological data, may result in confusion due to magma contamination, post-magmatic alteration, and secular change of mantle thermal conditions. We propose that a direct comparison of normalized multi-element patterns and key binary plots from older volcanic rocks with their modern analogues provides a more viable and reliable method of basalt discrimination. Our OPS–petrology–geochemistry method allows us to confirm the above conclusions that the lavas of the Akiyoshi, Mino–Tamba and Southern Chichibu AC formed in oceanic islands, because they are associated with seamount OPS sediments, crystallized from ol to cpx and pl, contain Ti–augite and kaersutite and are enriched in TiO2, LREE and Nb. In this paper we present geochemical data from the Inuyama basalts of the Mino–Tamba AC and from the Toba complex in the huge Mikabu greenstone belt of the Chichibu AC. The Inuyama basalts are in contact with Jurassic pelagic cherts, but their geochemical features are confusing; they contain phenocrysts of ol, Ti–augite and kaersutite and therefore probably formed in seamounts. The Toba volcanic rocks are a part of the huge ophiolite belt; they have flat to slightly LREE-enriched REE patterns, are characterized by an ol → cpx succession of phenocrysts and they plot in the OIB field in binary plots suggesting they formed in an oceanic plateau.

In managed forests, partial harvest within riparian areas is one way to provide harvest opportunities and maintain some of the functions of riparian vegetation. We examined the response of coniferous seedlings to a 50 %-partial harvest in a second-growth, coniferous riparian forest in the Pacific Northwest. Partial canopy opening facilitated the establishment of Tsuga heterophylla and Thuja plicata, but Pseudotsuga menziesii did not show the same tendency. Results suggested that differences in seedling establishment were related to differences in light. Increased light availability also stimulated growth of Rubus spectabilis, especially in moist sites, and the dense cover precluded establishment of coniferous seedlings. Once R. spectabilis was established, continued stem recruitment maintained a dense stable cover, and even intense disturbance did not affect the stability of the populations. R. spectabilis would be a major competitor to constrain conifer seedlings to regenerate in riparian zones. Although Gaultheria shallon extended their cover, competition from dense G. shallon was not as severe as from R. spectabilis.

The relationship between large deep-seated landslides and geologic structures characteristic of accretionary complexes were examined in the Chichibu belt on the eastern part of the Kii Peninsula, central Japan. In the Chichibu belt, bedrock consists of Jurassic accretionary complexes composed of basalt, limestone, chert, Permian–Triassic boundary siliceous shale (PTBS), mudstone, sandstone, and melanges with sheared shale matrices. The landslides treated in this paper include prehistoric examples involving volumes greater than one million cubic meters (located in the Karako, Sono, Kasagi, and Aso areas), and the modern Kasugadani landslide that was triggered by the Typhoon Meari on 29–30 September 2004. The age of the landslide in the Sono area was estimated at 20,440 ± 70 BP and 20,820 ± 70 BP based on AMS-14C ages of wood fragments embedded in the dammed lake sediments, while ages of the other prehistoric slides are not known. All of the landslides occurred on dip slopes. The bedding, foliation, and fault planes of the rocks in the area generally trend E–W and dip to the north, although those in the Kasugadani area dip to the south as a result of local folding. The landslides selectively slid along the planes of (1) PTBS horizons that were less strong than those of underlying chert, (2) lithologic boundaries with physical contrasts, or (3) boundary faults between melange units. These geologic structures, including the north-dipping bedding/cleavage/fault planes, were formed during Jurassic subduction–accretion and later uplift processes. The movement directions estimated for the 269 landslides and unstable slopes in this region are also N–NNE, and their slip planes are subparallel to the general bedding/cleavage planes in this area. Thus, future slides are also likely to occur on north-facing slopes.

Large-scale landslides along the Kubusu and Besso rivers in Toyama Prefecture are developed in the Miocene Iwaine Formation, which is composed of andesitic lava, tuff, and tuff breccia. In the middle member of this formation, the tuff is easily altered to montmorillonite-bearing rock, and subsequently plays an important role in the development of landslides events, which tend to be large-scale events, as the massive lava of the upper member forms a cap rock over the tuff. The Kiritani and Koinami basins, which are flat intermontane basins located along the Kubusu and Besso rivers, respectively, are interpreted as landslide-dammed lakes, later filled with sediment. Accelerator mass spectrometry 14C ages show that the landslides forming each dam occurred simultaneously, at approximately 2500 BP. These ages were measured from wood fragments embedded in the landslide material of Kiritani, and from an in situ stump drowned during the impoundment of Koinami. If the trigger of these landslides was an earthquake, it is most likely to have been the penultimate event along the Atotsugawa fault zone.

Petrographic analyses of plutons across the Karakoram fault in the Shyok-Nubra confluence of northern Ladakh area revealed that the rocks consist of diorite, granodiorite, granite and leucogranite. Pyroxene and biotite chemistries by EPMA indicate that most of the diorite, granodiorite and granite are calc-alkaline and formed in an arc-related tectonic setting. These calc-alkaline plutons yield K–Ar biotite ages from 49.3 ± 1.1 to 51.2 ± 1.1 for Ladakh batholith in Khardung La and from 60.8 ± 1.3 to 65.8 ± 1.4 Ma for granites and diorites in Hundar area. The K–Ar ages of the Hundar igneous complex are within the age range of 46–70 Ma of the Ladakh batholith near Leh town and the neighbor sites, indicating the Hundar igneous complex as a part of the Ladakh arc. Their ages are also coincident with the Khardung volcanics (67.4 and 60.5 Ma). The calc-alkaline granites from Panamik of Karakoram block yield K–Ar biotite ages of 95.7 ± 2.1 and 96.7 ± 2.1 Ma, suggesting that the granites are member of the plutons (90–120 Ma) occurring in northern Pakistan, Tangtse in Ladakh and western Tibet that emplaced during subduction of the Neo-Tethyan oceanic plate under the Karakoram block. The leucogranite and granodiorite in the Panamik region yield K–Ar biotite and muscovite ages ranging from 9.18 ± 0.21 to 9.45 ± 0.21 Ma. The leucogranites are the S-type related to post-collision tectonic setting and are considered to have emplaced in relating to activation of the Karakoram fault.

Plume-related oceanic magmatism form oceanic islands, seamounts and plateaus (hereafter “seamounts” or “paleoseamounts”), which are important features in geological history. The accretion of oceanic seamounts to active continental margins significantly contributed to the formation of the continental crust. This paper reviews occurrences of Late Neoproterozoic–Mesozoic seamounts of the Paleo-Asian and Paleo-Pacific oceans, which are hosted by accretionary complexes (ACs) of Russian Altai, East Kazakhstan, Mongolia, Russian Far East and Japan. The paleoseamounts commonly consist of Ti–LREE–Nb-enriched plume-related basalts (OIB-type or intraplate basalts) capped with massive limestone and associated with other units of oceanic plate stratigraphy (OPS): oceanic floor basalts (MORB), pelagic chert, epiclastic slope facies, etc. The paper presents available geochemical data on the plume-related basalts including the first geochemical data on the Middle Paleozoic OIB-type basalts of the Paleo-Asian Ocean hosted by the Ulaanbaatar AC of Mongolia. An emphasis is made for the structural setting of OPS units, specific geochemical features of intraplate basalts, problems of their identification, and distinguishing from magmatic units of a different origin such as MORB, island-arc and back-arc basalts. Finally, we propose a continuous, though periodical, evolution of the Pacific superplume-related magmatism, which can be more reliably proved by studying Middle Paleozoic OPS units hosted by ACs of Mongolia and Tien Shan, and discuss prospects of future studies.

The garnet-kyanite-staurolite and garnet-biotite-staurolite gneisses were collected from a locality within Lukung area that belongs to the Pangong metamorphic complex in Shyok valley, Ladakh Himalaya. The kyanite-free samples have garnet and staurolite in equilibrium, where garnets show euhedral texture and have flat compositional profile. On the other hand, the kyanite-bearing sample shows equilibrium assemblage of garnet-kyanite-staurolite along with muscovite and biotite. In this case, garnet has an inclusion rich core with a distinct grain boundary, which was later overgrown by inclusion free euhedral garnet. Garnet cores are rich in Mn and Ca, while the rims are poor in Mn and rich in Fe and Mg, suggesting two distinct generations of growth. However, the compositional profiles and textural signature of garnets suggests the same stage of P -T evolution for the formation of the inclusion free euhedral garnets in the kyanite-free gneisses and the inclusion free euhedral garnet rims in the kyanite-bearing gneiss. Muscovites from the four samples have consistent K-Ar ages, suggesting the cooling age (∼ 10 Ma) of the gneisses. These ages make a constraint on the timing of the youngest post-collision metamorphic event that may be closely related to an activation of the Karakoram fault in Pangong metamorphic complex.

Background: Although the circumstances surrounding falls among community-dwelling elderly people have been described by numerous studies, there are few that have reported falls in the northern regions of Japan, such as Hokkaido, that experience a severe winter with heavy snow. As a preliminary study, we surveyed the circumstances of falls among community-dwelling elderly people in Hokkaido with a self-administered questionnaire. Methods: Residents living in private homes throughout Hokkaido were randomly contacted by telephone and those aged over 65 years were recruited for this study. In all, 1000 subjects participated in the survey. A questionnaire was used to obtain the histories of falls, including the number of falls, the season and place of occurrence, and the cause of the falls in the year prior to the survey. Results: Of the 1000 subjects, 849 (436 men and 413 women; mean age, 73.0 years) completed the questionnaire. Among the 849 subjects, 277 (32.6%) fell at least once during the year of the survey. Of these 277 subjects, 155 subjects (56.0%) experienced two or more falls in the year. Approximately 60% of the falls occurred during the winter. The most common location where falls occurred was on roads or sidewalks, and slipping was the most prevalent cause. Conclusion: Our findings revealed several aspects regarding the circumstances surrounding falls among community-dwelling elderly people in Hokkaido.

The Anyui Metamorphic Complex (AMC) of Cretaceous age is composed of metachert, schist, gneiss, migmatite and ultramafic rocks, and forms a dome structure within the northernmost part of the Jurassic accretionary complex of the Samarka terrane. The two adjacent geological units are bounded by a fault, but the gradual changes of grain size and crystallinity index of quartz in chert and metachert of the Samarka terrane and the AMC, together with the gradual lithological change, indicate that at least parts of the AMC are metamorphic equivalents of the Samarka rocks. Radiolarian fossils from siliceous mudstone of the Samarka terrane indicates Tithonian age (uppermost Jurassic), and hence, form a slightly later accretion. This signifies that the accretionary complex in the study area is one of the youngest tectonostratigraphic units of the Samarka terrane. The relationship between the Samarka terrane and AMC, as well as their ages and lithologies, are similar to those of the Tamba–Mino–Ashio terrane and Ryoke Metamorphic Complex in southwest Japan. In both areas the lower (younger) part of the Jurassic accretionary complexes were intruded and metamorphosed by Late Cretaceous granitic magma. Crustal development of the Pacific-type orogen has been achieved by the cycle of: (i) accretion of oceanic materials and turbidites derived from the continent; and (ii) granitic intrusion by the next subduction and accretion events, accompanied by formation of high T/P metamorphic complexes.

In this study, we described the joint angle changes of the trailing leg during the compensatory step used to recover balance following a forward slip while walking. Fifteen healthy young males walked on a walkway which incorporated a movable platform to simulate a forward slip while walking. In 12 out of the 15 subjects, the trailing leg was rapidly lowered during the swing phase and was placed on the ground behind the slipping foot following the onset of the slip. Time taken for the onset of the slip to the placing of the trailing foot was 0.28+/-0.03 s. The amount of hip flexion lessened after 52% of the normalized time, with 0% being the onset of the platform movement and 100% representing the placing of the trailing foot on the ground. The flexed knee began to extend at 72% of the normalized time, which continued until the foot was firmly placed. The plantarflexed ankle began to dorsiflex at 56% of the normalized time, the angle of which peaked at the moment the toe made contact with the walkway again-the end of the movement. These findings aided us in understanding the mechanism underlying the compensatory step to recover the loss of balance caused by a forward slip while walking.

Callovian (late Middle Jurassic) ammonoids Macrocephalites and Jeanneticeras were recovered from the Shyok suture zone, northeast of Chang La Pass, Ladakh, northwest India. They are the first reliable Jurassic fossils and the oldest chronologic data from the Shyok suture zone. The ammonoid-bearing Jurassic strata, newly defined as the Tsoltak Formation, consist largely of terrigenous mudstone with thin sandstone beds and were probably a part of the continental basement to the Cretaceous Ladakh Arc.

n attempt was made to classify vegetation of the High Arctic of Canada at the higher level of syntaxonomy. Provisionally, one class, two orders and four alliances in addition to unclassified "polar desert complex" were distinguished. They were: the Salicetea arcticae, incorporating the Saxifragetalia oppositifoliae and the Caricetalia stantis. The Saxifragetalia oppositifoliae comprised of three alliances, i.e., Papaverion lapponici, Dryado-Salicion arcticae, and Cassiopion tetragonae, in addition to the "polar desert complex". Under the Caricetalia stantis, one alliance Caricion stantis was recognized. Vegetation of the Canadian High Arctic was compared with that of Svalbard. The most striking difference between the two regions was a presence/absence of Cassiope tetragona in the zonal phytogeocoenoses. The Cassiope-dominating communities are fairly common in Svalbard whereas they are generally limited in the Canadian High Arctic. Such difference was explained primarily by climatic characteristics and concomitant soil properties in such a manner that a highly continental climate of the Canadian High Arctic decelerates the soil leaching and eluviation to maintain generally high base status of soils. On the other hand, a strongly oceanic climate of Svalbard promotes soil leaching to result in a soil acidifi-cation. Cassiope tetragona is known to be acidophilous and thrives better in acidic soils. In the Canadian High Arctic, development of the Cassiope-dominating communities is rather restricted to the areas where soils are generally acidic. Such a climate-soil-vegetation interaction regulates development of zonal phytogeocoenoses to determine biogeoclimatic characteristics of the respective regions.

地下深部の割れ目の特徴を明らかにするために, ボーリングコアに認められた割れ目とボアホールテレビ画像に認められた割れ目を対応させ, 割れ目の走向・傾斜, 割れ目面の形状, 充填鉱物などについて検討を行った. 研究対象は, 岐阜県土岐市で掘削された垂直ボーリング孔の深度51～1,012mの部分で, 白亜紀後期の土岐花崗岩である. 割れ目は, 急傾斜でNNW, NS, NE～ENE走向のものと水平なものが卓越する. 深度別に見ると, 急傾斜割れ目の走向は, 深くなるにつれ, NNW→NNE, ENE→EWへと変化する. 割れ目の形状には, 直線的ででこぼこしたもの (Pr), 平らなもの (Pf), 条線がみられるもの (Ps), および, 起伏してでこぼこしたもの (Wr) が認められる. Ps割れ目の解析から, 深度340m付近に, 横ずれのせん断運動によって形成された, NNW-SSE走向で急傾斜の割れ目群があることが明らかとなった. Pr, Pf, Ps割れ目は急傾斜のものがほとんどで, 形状等の特徴からせん断運動によって形成されたものと推定される. Wr割れ目は水平なものと急傾斜のものの両方がある. このうち, 浅部にみられる水平なものの一部はシーティング割れ目, その他のものは冷却割れ目である可能性が高い.

滋賀県東部の伊吹山の西麓を流れる姉川沿いには, 葉理・層理が発達した泥層が分布する. この泥層は, 岩相・分布などの特徴や伊吹山西面の崩壊堆積物との位置関係から, 伊吹山の大規模斜面崩壊によって形成されたせき止め湖堆積物と考えられる. この堆積物には新期・古期の2種類があり, 新期せき止め湖堆積物には, 砕屑粒子・珪藻殻・菱鉄鉱微粒子・有機物などからなる薄い葉理をもつ部分がある. この葉理は春にブルーミングを迎える珪藻の殻が濃集した葉理と湖底が還元的となる夏に形成される菱鉄鉱および粘土鉱物の濃集した葉理が繰り返す年縞に, 粗粒砕屑粒子・植物片などの有機物が時折供給されて形成されたものと考えられる. 新期・古期せき止め湖堆積物に含まれる植物遺体の14C年代は, ばらつきが大きいものの, それぞれ約5,000年前, 約3万～4万年前であった. 本研究で得られた14C年代, 葉理をもつ泥層から推定される堆積期間, 既往研究による火山灰の存在や古文書記録などから, 姉川流域にせき止め湖を出現させ, 長い期間存続させるような斜面崩壊が, 伊吹山西面で少なくとも過去に2度発生したことが明らかとなった.

Vegetation of Sitka alder(Alnus sinuata) thickets occurring in the subalpine environment in the Thompson Pass area, the Chugach Mountains, Alaska, was studied. On the southern slopes of the Chugach Mountains facing the Pacific Ocean, the subalpine zone develops in an altitudinal range approximately from 100m up to 800m above sea level. There a complex of shrub thickets of Alnus sinuata and open dwarf shrub meadows best represented the vegetation. A total of 52 releves were established to describe the vegetation structure; 32 releves representing the Alnus sinuata thicket and 20 releves the open dwarf shrub meadow. For each releve, all the vascular plants were listed and their coverage was assessed. Vegetation synthesis tables were constructed. Vegetation was classified according to phytosociological methods. Two plant associations, Calamagrostido canadensis-Alnetum sinuatae and Empetro nigri-Vaccinietum caespitosi, were identified; the former association represented the Alnus sinuata thickets and the latter open dwarf shrub meadow communities. The ecogeographical status of the Alnus sinuata thicket is discussed in relation to other subalpine biomes of the northern Amphi-Pacific region. It is concluded that the Alnus sinuata thicket represents a mild winter but snowy oceanic subalpine environment of the southern slopes of the Chugach Mountains, Alaska.

The Khabarovsk Complex, a Jurassic accretionary complex distributed in and around the Khabarovsk city area, Far East Russia, comprises melange and schist facies. From the review of previous studies including Russian papers, the lithology and age of the constituent rocks of the melange facies can be summarized as follows: Upper Paleozoic basic volcanic rocks, mainly pillow lava, and altered gabbro, Upper Carboniferous to Upper Permian fusulinoidean-bearing limestone associated with tuff, Lower and Middle Jurassic siliceous mudstone, Upper Jurassic tuffaceous mudstone, uppermost Jurassic carbonate concretions embedded in mudstone, and age-unknown sandstone. Newly found sequences of limestone-chert and of basalt-chert in the melange facies crop out along the Amur River in the Khabarovsk city area. A chert sample of the limestone-chert sequence contains Albaillella aff. asymmetrica and Pseudoalbaillella aff. lomentaria, and a chert sample of the basalt-chert sequence includes Follicucullus monacanthu...

A permanent plot was established in 1997 to monitor vegetation development in a recently abandoned coal mine in Ny-_lesund, Svalbard. A 1 mx1 m quadrat was set up and further divided into one hundred small 10 cmx10 cm cells. All the vascular plants occurring in the plot were recorded for each of the 100 cells. In 1999, the plot was revisited and examined for occurrences of vascular plants. Further, in 2002, the plot was re-surveyed and all the vascular plants were measured for their coverage. Data were compared and coverage change over the past three years was detected. Vascular plants significantly increased, indicating that the vegetation succession is currently in progress.

従来, 飛騨外縁帯の分布・区分などには多くの混乱と問題があったため, その発達史を議論する上で大きな障害となっていた. 従来飛騨外縁帯として扱われてきた地層・岩体は, 岩相とその占める空間的位置により, (1) 中～上部古生界浅海成層を主体とする地層群 (宇奈月帯構成岩類を含む), (2) 300Ma以前の変成岩を含み, 苦鉄質～超苦鉄質岩を主体とするもの, (3) 後期古生代の石灰岩・チャート・砕屑岩主体層, (4) 苦鉄質岩とペルム系砕屑岩, の4つに大別される. 後三者は, それぞれ三郡—蓮華帯, 秋吉帯および舞鶴帯に帰属を求めることができ, 本論では (1) の分布域を飛騨外縁帯として再定義することを提案し, その模式地は福地・本郷・古川地域とする. 本論の飛騨外縁帯構成岩類は, 宇奈月, 白馬岳, 福地・本郷・古川, 〓谷, 石徹白, 朝日, 伊勢・大野の各地域に分布し, それらは各地域内で断層もしくは剪断帯で寸断されてブロック化している.

美濃帯のジュラ紀メランジュを構成する混在岩のボーリングコアを使用してトランジェントパルス法により室内透水試験を行い, 透水係数を測定した. 測定には, 中期ジュラ紀の上麻生ユニットに属し土岐花崗岩の接触変成作用を被った丸山コアと, 後期ジュラ紀から最前期白亜紀の金山ユニットに属する非変成の伊自良コアを用いた. その結果, 丸山コアは10-13～10-15m/sec, 伊自良コアは10-11～10-15m/secの透水係数を示し, ともに難透水性岩石であるが, 接触変成作用を被った丸山コアの方がより透水性が低いことが明らかとなった. また, 一般に透水性に影響を与えると考えられる, 混在岩の面構造と試料の長軸方向のなす角度と透水係数の間には相関はみられないのに対し, 透水係数と試料の間隙率の間には相関が見られ, 間隙率が大きいほど透水性が高いことが示された. また, 伊自良コアでは透水係数と試料に含まれる砂岩ブロックの割合の間に弱い相関が見られ, 砂岩ブロックの量が多いほど透水係数が高い.既存の資料を評価し, メランジュと推測される岩体について行われた原位置透水試験結果をまとめた. 同程度の深度で比較した場合, 室内試験で得られた透水係数は原位置試験で得られた透水係数より4乗～7乗オーダー小さな値であった.

Small-scale geomorphic features of sagging have been known to occur in mountainous areas in Japan by the analyses of high resolution map images made from the LiDAR data. Development histories of the sagging landforms were analyzed by the GIS analyses, field mapping, machine and hand auger boring, AMS 14C dating, and tephra geochronology in the Mt. Kanmuriyama, Tsuenomine and Nogo-Hakusan areas. Sediments accumulated in the ridge-top depression in the Mt. Kanmuriyama area yield wood fragments with the ages of 1,234–1060, 6,191–5,996 and 7,931–7,731 cal BP, and also include the K-Ah tephra of ca 7.3 ka. These ages indicate that the depression started to form at the beginning of warm and humid climate after the last glacial period. On the other hand, the double ridges in the Mt. Tsuenomine area formed much earlier before the deposition of the Kikai-Tozurahara tephra about 95 ka. The GIS analyses of sagging in the Mt. Nogo-Hakusan area indicate that most of them are distributed on the flat or gentle surface just above the knick line (erosion front); it means that the knick lines retreat through the repetitive formation and destruction of the sagging landforms.

The paper presents the results of a detailed geochemical study (major and trace elements, Sr, Nd and Pb isotopes) of early Carboniferous to Miocene volcanic rocks of the Akiyoshi, Mino–Tamba, Chichibu and Shimanto accretionary complexes of Japan in combination with an analysis of their geological relations with sedimentary units and their petrogenesis (melting modeling). Most of the samples are oceanic island basalts (OIBs) associated with Carboniferous–Cretaceous sediments of Ocean Plate Stratigraphy (OPS): carbonate “cap” limestones, hemipelagic siliceous mudstone and pelagic radiolarian chert. The basalts are enriched in TiO2, LREE (La/Smn = 1.9), and Nb (Zr/Nbav. = 10), have differentiated HREE (Gd/Ybn = 2.0), medium to low eNd (7.8–2.2) and are characterized by clear Nb positive anomalies in multi-element plots (Nb/Thpm = 1.3, Nb/Lapm = 1.1). The Carboniferous–Cretaceous OIBs originated at relatively low degrees of melting (

In 1997,a permanent plot was established in an abandoned coal mine site on the outskirts of Ny-Alesund, Svalbard, to describe the present vegetation structure and to monitor future vegetation change. A 1m×1m quadrat was set up and was further divided into 100 small cells (subquadrats). All the vascular species were listed and their presence was recorded for each of the subquadrats. In 1999,the plot was revisited and all the subquadrats were rechecked for any change of species occurrence. The field data of 1997 and 1999 were compared and change of species occurrences was scrupulously examined for each subquadrat. In general, a considerable increase of occurrences of plants as expressed in the number of subquadrats took place during the two years. This suggested that even during the observation period the vegetation kept changing rapidly along with the progress of vegetation succession.

Effects of experimental warming on shoot developmental growth and biomass production were preliminarily investigated in two evergreen dwarf shrubs Empetrum nigrum and Loiseleuria procumbens, using the International Tundra Experiment’s open-top chamber (OTC) method, in the Tateyama Range, central Japan. An OTC was installed over shrub (E. nigrum and L. procumbens) -dominated vegetation and over shrub-forb (such as Anemone narcissiflora var. nipponica and Solidago virga-aurea ssp. leiocarpa) mixed vegetation, and stem samples of the evergreen shrubs were obtained at 26 months after installing the OTC. The OTC increased the daily mean temperature by 0.1°C to 1.8°C, on average, during the growing season. Shoot developmental growth and biomass production were considerably different between species of different vegetation types. The boreal species E. nigrum generally showed better growth inside the OTC than the arctic and subarctic species L. procumbens. Both species showed significantly larger shoot elongation and biomass production inside the OTC over shrub-dominated vegetation, whereas smaller or reduced growth was detected inside the OTC over shrub-forb mixed vegetation. The variations of growth responses to warming between species of different vegetation types are discussed, especially in relation to interspecific competition under a simulated environmental change.

岐阜県丹生川村横尾地域より, 泥岩, 砂岩と珪長質凝灰岩とを主体とするペルム系を見い出した.本層は, 従来, 異地性岩塊を含むメランジュを主体とするジュラ紀付加体の美濃帯駄吉層に含められることもあったが, 駄吉層より分離し, 十二ヶ岳層として再定義する.十二ヶ岳層は, 著しく破断された砂岩泥岩互層からなる下部層と, 珪長質凝灰岩泥岩互層を挟む砂岩泥岩互層からなる上部層とに区分される.上部層の珪長質凝灰岩泥岩互層は, ペルム紀新世前期を示すFollicucullus charvetiをはじめ, ペルム紀の放散虫化石を多産する.十二ヶ岳層は主にその岩相層序, 産出化石, 堆積時代に基づき, 超丹波帯の大飯層に対比される.従来, 中部地方では福井県南条地域を除いて, 超丹波帯構成層に対比される地層の報告は無い.しかし今回の発見は, 超丹波帯構成層に対比される地層が美濃帯北縁部に沿って, 断片的に存在する可能性を示唆する.

Paleomagnetic and paleontologic studies of Middle Triassic to earliest Jurassic radiolarian bedded chert in the Inuyama area, southern Mino terrane of central Japan, have shown that the chert was deposited in an equatorial region with a paleolatitude between 10°N and 10°S, and in particular, the lower to middle Anisian chert depositional basin was situated in the Southern Hemisphere. The chert has four characteristic components of remanent magnetization. The highest blocking temperature component, carried by hematite, shows positive fold and reversal tests and is regarded as the primary remanent magnetization acquired just after deposition. The other three components are interpreted as a present field overprint and two postfolding remagnetizations. The absolute, tilt-corrected inclinations of the primary component are less than 20° for all the samples of Middle Triassic to earliest Jurassic age, with the mean inclination of the lower to middle Anisian chert being 11.0°±4.3°. Paleomagnetic polarity reversals observed for the lower to middle Anisian chert are well correlated with those of the European Triassic sections, under paleontologic age constraints using radiolarians and conodonts, provided that the Anisian chert in Inuyama was deposited in the Southern Hemisphere. This conclusion illuminates the paleogeographic evolution of the chert-bearing accretionary complexes not only in Japan but along the eastern margin of Asia as well.

This paper briefly describes the geology of southern Sikhote-Alin of Russia and the Inner zone of Southwest Japan, and presents a new correlation model in which the Samarka terrane (sensu stricto), Udeka Formation, Sebuchar Formation and Kalinovka ophiolite in Sikhote-Alin are considered as northern extensions of the Mino-Tamba terrane, Hikami Formation, Kozuki Formation, and Yakuno ophiolite in Southwest Japan, respectively. This correlation is based on the similarities in lithology, age, faunal assemblage, and structural relationship between them. The Samarka and Mino-Tamba terranes consists of Jurassic accretionary complexes including Permian greenstone-limestone complex, Permian to Lower Jurassic radiolarian bedded chert, Jurassic clastic rocks, and Jurassic melanges. The Udeka and Hikami formations are composed mainly of greenish gray sandstone with minor shale intercalations yielding Permian radiolarians. The Sebuchar and Kozuki formations are characterized by basalts accompanied with shale, limestone and chert. The limestone includes Carboniferous fusulinaceans, while Permian radiolarians occur in the chert. The Kalinovka and Yakuno ophiolites consist of a series of ultramafic to mafic igneous rocks with an ophiolitic succession. Since the ages of these ophiolites have not been clearly established, we correlate them on the basis of their lithology and tectonic positions. These units form a stack of nappes from the lower to upper horizons in the following order: Mino-Tamba terrane, Hikami Formation, Kozuki Formation, and Yakuno ophiolite in Japan, and Samarka terrane (sensu stricto), Udeka Formation, Sebuchar Formation, and Kalinovka ophiolite in Russia. This correlation supports the reconstruction model of Japan before the opening of the Sea of Japan proposed by Yamakita and Otoh (1999).

Relationships between the NDVI and vegetation, especially for the nine dominant vegetation types of Tibetan Plateau, were examined and discussed using GIS and remotely sensed data. The results showed that the yearly averaged NDVI of the study region was 0.064. In 88.5% of the area, NDVI were lower than 0.1 and the monthly mean values never exceeded 0.1 throughout the whole year in half of the Plateau. The NDVI values steadily decreased from the southeast where evergreen and semi-evergreen rain forest was well developed to northwest where cold desert was dominant. It is clearly shown that the main vegetation types have their own NDVI character values, despite of the fact that the vegetation is sparse for the most part of the region.

美濃帯南部の尾崎-雨池地域と飛水峡地域の三畳紀層状チャートには, まれに, 砕屑岩層が挟まれる.砕屑岩層の上部と下部のチャートから取り出した放散虫は, 砕屑岩の堆積年代が, 尾崎地域ではCarnian前期, 雨池地域ではLadinian中期とCarnian前期, 飛水峡ではAnisian後期～Ladinian前期であることを示している.これらの年代はAnisian後期～Carnian前期に集中しているが, 全く同じ層準ではない.含まれる砕屑粒子の種類は, チャート・珪質頁岩・塩基性ないし中性火山岩・変質した火山ガラス・多結晶石英・ドロストーン・海緑石様鉱物(シデライトを伴うことがある)・ルーテサイト・アパタイト・放散虫・コノドントなどである.全ての砕屑粒子の起源を満足する単一の後背地を想定することは困難であるが, 後背地の候補としては, 海洋島・島弧・陸棚・より古い付加体などが考えられる.

Exceptionally well-preserved Eocene plant fossils occurring in leafy litter mats from the Buchanan Lake Formation, Canadian Arctic, make it possible to estimate the accumulation rate of the lignite. This method is based on the assumption that the projected leaf-surface area of individual tree species per unit of ground-surface area (leaf-area index) is more or less constant. The calculated accumulation rate of 1.6 mm/year has been corrected to the minimum accumulation rate of 0.8 mm/year by considering the effects of organic decomposition. Since the compaction ratio of the leaf lignite is difficult to estimate, correct comparison with accumulation rates of modern and Quaternary peats that have been determined by using 14C ages is impossible. However, the accumulation rate calibrated in the peat stage of coalification by using the compaction ratio of woods embedded in the leaf lignite is within the range of accumulation rates determined for modern and Quaternary peats.

We examined the effects of short term artificial warming from 4 July to 19 September 1996 (78 days) in an open top chamber (OTC) on fruit production of a deciduous alpine shrub Geum pentapetalum (L.) Makino (Rosaceae) in the Tateyama Range, Toyama, Japan. Daily maximum temperature in the growing period significantly increased ca. 3.6℃ inside the OTC as compared to outside the chamber, while daily minimum temperature significantly decreased ca 1.3℃ inside the OTC. Daily mean temperature was not significantly different inside and outside the OTC. There were not any significant differences of shoot characteristics such as the number of leaves, total leaf mass and current stem weight inside and outside the OTC. Dry weight of the main body of the achene (including seed) and individual achene size (IAS) were significantly increased by OTC treatment, while the plume was not. Seed ripening, estimated number of achenes (ENA) and estimated total achene mass per shoot (EAM) slightly increased inside the OTC, but they were not significantly different between the shoots affected by OTC and the unaffected. EAM was significantly positively correlated with current basal stem weight both in OTC-affected and -unaffected shoots. Analysis of covariance showed that EAM in a given stem size was significantly higher in OTC affected shoots than in the -unaffected shoots. These results imply an importance of interaction between fruit production and shoot size when we assess the effects of artificial warming on reproductive traits. Thus, we found that short-term artificial warming first affected the size rather than the number of seeds and fruits, and the reproductive organs were more sensitive to warming than vegetative organs of Geum pentapetalum, at least according to the dry weight based analysis.

Two mini-open top chambers (OTCs) were installed at a high elevation site of 2850 m above sea level on the Tateyama Range, Toyama Prefecture, Japan, to generate an artificially warmed environment and to assess growth responses of two alpine plants, Empetrum nigrum L. and Loiseleuria procumbens DESV. to the warmed environment. A total of 80 twigs of the said species, ten each from inside and outside of the two OTCs, were randomly chosen. They were tagged and periodically measured for their current year shoot elongations. Data loggers were set inside and outside one of the chambers (OTC 1) to record ground surface temperatures at every one-hour interval for 76 consecutive days from July 15th to September 30th, 1995. Mean daily temperature was 2.1℃ higher on average inside the OTC 1 than outside. The OTC especially elevated daily maximum temperatures to result in a considerable larger diurnal temperature ranges inside the chamber. The OTCs substantially stimulated plant growth by increasing temperature inside the chambers. In both of the OTCs, shoot elongation was significantly greater inside for both species, presumably reflecting the ameliorated environment.

Magnitudes and extent of forest decline due to industrial pollution in Monchegorsk on the Kola Peninsula, Russia, were assessed by Landsat data and ground observation. A total of 1, 098 km2 was identified to be affected. The area was classified into three damage classes. i. e., light, medium, and heavy, and their areal extents were estimated to be 865 km2, 147 km2 and 86 km2, respectively. Economical loss due to the decline was evaluated. Potential annual total loss of wood increment amounted to be 81, 000 m3 for the entire area and its commercial value was estimated to be 8.1 million US dollars. Wild berry production of 3, 300 ton/year was also lost, which would worth 16.5 million US dollars approximately. Loss of ecological functions of the forest ecosystems was immeasurable. Such economical and ecological losses would last “forever” from our perception of time. This was totally contradictory to the notion of sustainable resource use with which the whole world was so much concerned.