http://www.sciencedirect.com/science/article/pii/S167498711200062X

This paper focuses on the formation mechanism of fractures induced by excavation of a gallery in soft sedimentary rocks in the Horonobe area of Japan.Detailed fracture mapping of the gallery indicates that the fractures consist of both pre-existing shear fractures and excavation damaged zone(EDZ) fractures. EDZ fractures correspond to weak planes associated with bedding planes or transgranular cracks.The EDZ fractures terminate against pre-existing shear fractures.Therefore,even for excavations in soft sedimentary rocks,formation of the EDZ fractures are controlled by pre-existing fractures and earlier weak planes.     

Olivine-rich exposures in the South Pole-Aitken Basin

The distribution and the geological context of the olivine-rich exposures in the South Pole-Aitken (SPA) Basin on the Moon were investigated based on the spectral data obtained from the Spectral Profiler (SP) and Multiband Imager (MI) onboard the Japanese lunar explorer Kaguya/SELENE. The olivine-rich exposures are found only in the peak rings or central peaks of the Schrödinger basin and Zeeman crater, which are located in the outer region of the SPA Basin and not in the center region. On a localized scale, the olivine-rich materials are exposed on landslide features on the crater walls or sloped wall of the central peaks or the peak rings. Another observational finding is the co-existence of olivine-rich and plagioclase-rich materials on a kilometer scale spanning most of the olivine-rich sites in the Schrödinger basin. Pyroxene-rich materials are found in fresh craters outside the peak rings or the central peaks with olivine-rich materials. Based on these results, the following scenario are proposed: (1) the impact to form the SPA Basin melted a large amount of the lunar upper mantle and crust, and distributed the melted materials to the outer region; (2) local differentiation of melted materials hid the olivine-rich materials in the center region of the SPA Basin; (3) later impacts that formed the Schrödinger and Zeeman craters excavated and exposed the olivine-rich materials to the surface again; and (4) space weathering and regolith gardening obscured the olivine-rich spectra at the exposure sites, but recent, small scale impacts or landslides on the sloped wall exposed fresh olivine-rich materials, allowing the identification of the olivine-rich exposures by spectral remote-sensing. This suggests that several, different scale events play an important role in forming the surface distributions of originally deep-seated materials on the Moon, as well as on other planetary bodies.     

Seasonal occurrence and microhabitat of the hyperparasitic monogenean Udonella fugu on the caligid Copepod Pseudocaligus fugu infecting the grass puffer Takifugu niphobles in the Seto Inland Sea, Japan

The seasonal occurrence and microhabitat of the monogenean Udonella fugu that hyperparasitizes exclusively on adults of the caligid copepod Pseudocaligus fugu that infects the skin of the grass puffer Takifugu niphobles were investigated in the Seto Inland Sea, western Japan from November 2004 to December 2006. The udonellids occurred and bred mostly during the occurrence of P. fugu on the fish host. The average prevalence and intensity of U. fugu on P. fugu during the whole investigation were 29% and 3.6, respectively. The main attachment sites of U. fugu were the posterior side of leg 3 and the dorsal marginal side of the cephalothorax for feeding and copulation, while eggs were predominantly located on the ventral side of the urosome to avoid detachment. More attention should be paid to the ecology of U. fugu, due to recent high prevalence of P. fugu on cultured tiger puffer in western Japan.     

Formation age of the lunar crater Giordano Bruno

Abstract— Using the Terrain Camera onboard the Japanese lunar explorer, SELENE (Kaguya), we obtained new high‐resolution images of the 22‐kilometer‐diameter lunar crater Giordano Bruno. Based on crater size‐frequency measurements of small craters (<200 m in diameter) superposed on its continuous ejecta, the formation age of Giordano Bruno is estimated to be 1 to 10 Ma. This is constructive evidence against the crater's medieval age formation hypothesis.     

Observation of wave transformation on a sloping type B shore platform under wind-wave and swell conditions

An instrumented field study of the across-shore evolution of wave characteristics was conducted under wind-wave and swell-wave conditions on a sloping type B shore platform along the mesotidal, fetch-limited coast of Auckland, New Zealand, based on spectral analysis of hydrodynamic data recorded in pressure-sensor time series during a 24-h deployment on 24–25 November 2008. The results highlight the ability of the shore platform in dissipating wave energy reaching the cliff toe under wind-wave and swell-wave conditions, and the spectral redistribution of wave energy. As waves propagated onto the platform surface and towards the cliff toe, infragravity-wave energy became progressively more dominant, while gravity waves were dissipated. Wave height and period in the central sector of the platform and at the cliff toe were not markedly affected by differences in incident-wave conditions observed during the survey. The findings confirm the importance of platform morphology in modulating wave-energy delivery to the cliff toe. In contrast to previous studies, infragravity-wave height at the cliff toe did not appear to be correlated to incident-wave conditions.     

Mathematical modeling of biologically mediated redox processes of iron and arsenic release in groundwater

A one dimensional reactive transport model was developed in order to illustrate the biogeochemical behavior of arsenic and iron reduction and release to groundwater that accounts for the reaction coupling the major redox elements under reducing environment. Mass transport equation and the method of characteristics were used considering fundamental geochemical processes to simulate transport processes of different pollutants in mobile phase. The kinetic sub-model describes the heterotrophic metabolisms of several microorganisms. To model a complete redox sequence (aerobic or denitrifiers, Fe(III)-reduction, respiration bacteria of iron and arsenic compounds, and As(V) reduction) four functional bacterial groups (X ₁, X ₂, X ₃, and X ₄) were defined. Microbial growth was assumed to follow Monod type kinetics. The exchange between the different phases (mobile, bio, and matrix) was also considered in this approach. Results from a soil column experiment were used to verify the simulation results of the model. The model depicts the utilization of oxygen, nitrate, iron oxide and arsenic as electron acceptors for oxidation of organic carbon (OC) in a column. The OC as electron donor is one of the most important factors that affect the iron and arsenic reduction bacterial activity.     

Rocket measurements of the 6300 Å and 3914 Å dayglow features

Rocket results are presented on the OI 6300 Å line and on the N₂⁺ 3914 Å band in the dayglow. An altitude range of 78–335 km is covered. Theoretical interpretations are given, using results of simultaneous measurements of electron density and electron temperature. The apparent brightness of the 6300 Å line at the base of the emitting region is found to be 13 kR, of which 5.5 kR are ascribed to excitation through the Schumann-Runge dissociation of O₂ by the solar UV radiations, 0.55 kR to the dissociative recombination of O₂⁺ and NO⁺ ions, and 0.03 kR to the excitation of O by thermal electrons. An additional source of excitation above 280 km is suggested. The deactivation of O(¹D) by O₂(X³Σ_g⁻) is found to be appreciable below 200 km, and its rate coefficient is estimated to be 2 × 10⁻¹⁰ cm³/sec. The apparent brightness of the 3914 Å band at the base of the emitting region is found to be 6.5 kR, decreasing to 3.2 kR at 330 km. Assuming that fluorescent scattering of solar radiation is the mechanism involved the distribution of N₂⁺ ions is calculated. The rate coefficients for the loss of these ions are hence calculated.     

Research on the seismotectonics of the January 17, 1995 Hanshin M 7.2 earthquake

Based on the geological tectonics, aftershock activity, earthquake surface rupture and peak ground motion, the geometric and dynamic characteristics of seismogenic tectonics about the 1995 Hanshin earthquake are analysed. Nojima fault and Rokko fault have the same trending direction, but opposite dips. Their rising and falling plates are in symmetrically diagonal distribution. The two faults can be defined as thrust-strike slip faults and constitute a pivotal strike-slip fault. The earthquake just occurred at the pivot, which is the seismotectonics for the earthquake to develop and occur. The pivotal movement along a strike-slip fault often leads to the occurrence of large earthquakes, whose dynamic process can be demonstrated by the stress analysis on the torsion of a beam with rectangle section. The displacement of earthquake surface rupture, aftershock density and peak acceleration change in a certain range of epicentral distance just similar as the shear stress changes from the center to the sides in the rectangle section. The distribution characteristics of the heaviest damage areas are also discussed in the article from the aspects of special geological tectonics and seismotectonic condition. The result obtained from the article can be applied not only to realizing the potencial earthquake sources in middle-long time, but also to build reasonably the prediction model about earthquake hazard.     

Structural characteristics and tectonisms around the microcontinent in the outer margin of the Paleozoic-Mesozoic geosyncline of Japan

Consideration of the paleogeography and large and small structures in the outer part (the Sakawa Fold Belt) of the Paleozoic—Mesozoic geosyncline of Japan suggests that the main part of the Japanese Islands has grown up not from an arc—trench system but from a marginal sea basin—microcontinent system: the Chichibu Geosyncline and the Kurosegawa — Ofunato Island Arc, Minor structures are superposed in a complicated way and they are analyzed in terms of the concepts of tectonic level and multiple deformation.Stratigraphic evidence shows that an early deformation was pre-middle Triassic in the Chichibu Terrain but northwards in the Sambagawa terrain it may have continued until early Cretaceous in relation to minor scale subduction within the marginal basin. A late Cretaceous phase of deformation produced the greatest crustal shortening in the microcontinent area of the Kurosegawa Tectonic Zone and was nearly contemporaneous with the intrusion of granitic rocks in the Ryoke Zone Younger secondary eugeosynclines were developed by progressive encroachment on the arc—trench gap south of the Kurosegawa zone from late Permian times onwards.