Three series of model are prepared to examine what factor controls the precision of strain where the axial ratio of initial strain marker ellipsoids is assumed to scatter as a normal distribution. The average method is used to analyze the 3D strain of the present simulation. Three series of model are produced to test three factors; (1) sample size of markers, (2) mean of axial ratio of makers and (3) standard deviation of axial ratio of markers. The simulation is performed in three deformational fields; pure shear of plane strain, isochoric transpression and simple shear of plane strain. Results of the simulation are; (1) When the sample size of the initial strain marker ellipsoids is large, the precision of strain analysis is high. But the precision does not change over 300 sample size. (2) When the mean of axial ratio of the initial strain marker ellipsoids closes to unity, the precision of strain analysis is high. (3) If the standard deviation of axial ratio of the initial strain marker ellipsoids becomes smaller than unity, the precision of strain analysis becomes high. (4) These results hold almost in the same way for the three deformational fields. The exception is; the strain precision becomes high during the progress of deformation under the transpression and the simple shear, though the precision does not change during deformation under the pure shear.

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In hydrological flow simulation, suitable discretization of complex topography of surface or geological formations is necessary to reconstruct or predict fluid behavior with reliablity.
The authors present a methodology of constructing a flow-fitting grid system by using Spring-Mass Network model (SMNET) . The SMNET model that is put on the ground surface in tensional condition moves toward relaxed conditon in which total amount of gravitational and elastic energies of masses and springs becomes lowest, so that the final shape of SMNET can be suitable for flow simulation.
In this paper, the mathematical procedures of SMNET relaxation are fully described, as well as the algorithms of preparation stages for topographical data aquisition and height calculation by P-spline at arbitrary areal point. The SMNET is tested for generating grid system of actual field, and the characteristics of the performances with parameter variation are discussed.

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The main objectives of Frontier Research Program for Subduction Dynamics (FRPSD) are to ; (1) examine and reveal the mechanism of subduction zone earthquakes around Japan, (2) plan and carry out geophysical cruises and make related geophysical and geological observations of the trenches and associated subduction zones around Japan in support of (1) . In order to fulfill the above objectives, FRPSD research focuses on dynamics of the deep sea trenches using multi-channel seismic reflection (MCS) and Ocean Bottom Seismograph (OBS) tools and integration of these and existing data through sophisticated database procedure. In this paper, a brief introduction and application are presented of FRPSD's geophysical digital database. Marine geophysical data of bathymetry, geomagnetics, gravity, heat flow measurements, and crustal structure have been accumulated since the 1960's all over the world by oceanographic institutions including the Japan Marine Science and Technology Center (JAMSTEC) . We are developing a universal marine geophysical database system and making compilations and analyses of these data.
Several research vessels in JAMSTEC are equipped with the various required marine geophysical instruments. Geophysical data sets obtained by cruises are entered into the JAMSTEC Database. Subsequent selection, editing and formatting are then done to arrange the Frontier Database. The Frontier Database is then added to as additional Frontier data which are collected, employed for realistic parameters in modeling and simulation studies, and served as the basis for further cruise planning in less data dense areas.
Compilation of crustal structure, marine geomagnetic and gravity data off NE Japan is in progress to clarify characteristics of subducting plate magnetic lineations and trench gravity anomalies. Using 2-dimensional and 3-dimensional forward modeling of magnetic and gravity data, with seismic structural data in the Frontier Database, a qualitative interpretation of the geometry, densities, magnetization and thermal regime of these subducting plates is discussed. The features of geophysical properties are related to their origins, subsequent deformation and other possible processes of subduction. Several subduction models will continue to be examined as additional data are obtained by future Frontier surveys.

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The Middle Siwalik sediments of Jammu area consists of seven major lithofacies. A statistical analysis of lithofacies sequence using partial independence and entropy models reveals development of distinct cyclic order during deposition.
The upward transition path of lithologic states typical for this sequence is as follows: Planar cross-bedded sandstone (A) → Trough cross-bedded sandstone (B) → Mixed planar and trough cross-bedded sandstone (C) → Ripple cross-bedded sandstone (D) → Mottled silty sandstone (E) → Clayey siltstone (F) → Heterolithic siltstone (G) → Planar cross-bedded sandstone (A) .
This sequence is an asymmetrical cycle and can be identified into facies which are a result of deposition in channels (lithofacies A-E), flood-plains (lithofacies F) and interfluve areas (lithofacies G) . Entropy plots of the E ^(pre) and values of each lithological state correspond to the type A-4 category (Hattori, 1976), signifying lower and upper truncated asymmetrical cycles. The value of E _(system) falls within the boundary allocated for fluvial-alluvial succession.

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