To estimate a smooth trend of one dimensional data, a procedure based on the minimization of ABIC (Akaike's Bayesian Information Criterion) combined with local spline function is proposed. This is the development of Akaike's simple procedure based on the minimization of ABIC with a difference modeling, which only can treat the equidistantly distributed data (Akaike, 1980) . In this paper, the author explaines the theoretical treatment and numerical calculation method of the procedure in detail. A numerical example is also included to show the effectiveness the procedure.

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We examined the characteristics of the ground structure of the Karoeoka, Kyoto, Osaka basins and the Kumamoto Plain based or the boring database system of the areas with respect to: distribution of facies at the same elevations and depths; three dimensional projection of geological columns; distribution of the upper surface depth of pyroclastic flow deposits (ASO-4) ; calculation of appearance percentage of clay, sand and gravel at the same elevations and at 0.5m-intervals; Markov matrix which quantifies the transitions of facies: and distribution of N values in clay or sand at the same depths.

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Lineaments in Landsat TM images were analyzed using a image processing system consisting of apersonal computer, PIAS LA-500 and full color board. We studied the granitic body of stockform and cretaceous rocks in the northern part of Kumamoto prefecture. The first analysis of the digital terrain model of the granitic body revealed two prominent trends of maximum dip of slopes, NE-SW and NW-SE. The second revealed contrast modifications of the original TM images. The best method was obtained by flattening the frequency of the gray level (encoded brightness) in the original images. False color composition, which clarifies the geological structures of the granitic body. was carried out using these modified TM images. While TM images have 7 bands of wavelength, the data of band 5 corresponds well with the characteristics of the digital terrain model.
Furthermore, we evaluated a method of automatic detection of lineaments with a corrective function and differential filters. This method reduced the effect of the sun azimuth on the contrast of TM images and showed fracture patterns in the granitic body in detail. The fracture patterns were similar to those obtained by the analysis of aerophotographs of the studied area.

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The seismic tomography method has been developed and applied to the delineation of the formation boundaries and detection of the underground anomaly such as fault or underground cavity. The purpose of this paper is prepared in order to give introduction of the seismic tomography method with examples of practical application.
The details of this paper are summarized as follows.
(1) The theory of seismic tomography method
(2) Simulation models and tomographic analysis
(3) Data quality and corrections (quality controll)
(4) Examples of practical application

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A new system to describe zircon crystal forms has been developed. After measuring the thickness and the size of a crystal, four indexes are calculated: flatness, elongation, prism, and pyramid.
There are two basic forms for a zircon crystal according to the projected plane: either the {100} or {110} prism face. The prism face parallel to the projected plane is called “middle”, since it is located in the middle of the projected form. A projected form is classified into Type 100 or Type 110 based on the “middle”prism face, because each type has defferent equations.
The crystal faces observable from one direction are assumed to be the same size as those onthe opposite side. The vertical distance is called “height”, and the horizontal distance “Width”. The crystal “thickness”is measured under a microscope by focusing first on themiddle prism face and then on the surface of the glass slide on which the zircon crystals are scattered. The crystal sizes required for the calculation are: crystal height, crystal width, middle prism width, middle prism height, left and right prism heights of the outline, and left and right prism heights of the middle prism. The results ca be shorn on a table or on fourkinds of figures.
Requirements: PC-9801 computer with 640K main RAM, high resolution monitor, A5 size digitizer, plotter and printer.

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Many methods have been proposed to distinguish between dune, beach and river sand. In this paper a method of multivariate analysis is applied to investigate the subsurface distribution of dune sand. The numerical criterion for discrimination between dune and non-dune sand is calculated from the granular variations of dune sand which are taken from the surface of the investigated area. Based on the results obtained, the internal structure of the dunes developed along the coast of the Niigata Plain is discussed.

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BASIC program, which represents a lot of seismic data on the display of personal computer by several methods, is reported in this paper. The seismic data from 1926 to 1989 used in this program is quoted from ‘Rika Nenpyo’ and ‘Zisin’ (J. Seism. Soc. Jap.), which is based on JMA data. Any part of this data is able to be selected by input parameters and to be represented by some method. The methods of representation are as follows: (1) Time sequence distribution of magnitude of earthquakes, (2) Secular change of released energy by seismic wave, (3) Horizontal distribution of epicenters, (4) Distribution of seismic focuses with plots on three-side sectional maps, (5) Distribution of focuses with plots in 3-dimensional block diagram. By using this program, students' understanding of the occurrence pattern of earthquakes may be deepened.

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In this papar, we attempted the procedure for image processing by personal computer and presented an example of ground data in Kofu basin, Yamanashi prefecter.
Geological data correlating by the use of production-rule method can obtain good results.
By this method, this program is able to output geological columnar section, geological profile and panel-diagram to display.

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Computer programs estimating interpolated values on the regularly spaced grid points from irregularly distributed data are presented. We use an algorithm developed by Akima (1978) for the procedure. The algorithm can be divided into two part : (1) triangulation of irregularly spaced data points, and (2) polynomial surface fitting in every triangle. Corresponding theseprocesses, two computer programs are written both in C and FORTRAN77.

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Three compuier programs drawing a two-dimensional contour map, a three-dimensional bird-looking map with mesh lines and a three-dimensional contour map, respectively, are presented.They are coded in C and can run on the personal computer. Using one of these programs, highgrade graphic output is available both on a graphic screen and a XY-plotter.

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Stereographic projection is a useful tool to represent unit vectors in 3-D space. The principle of the projection based on 3-D geometry is hardly understood by students, because it is usually explained using figures drawn on 2-D plane. An interactive system of stereoscopy has been developed to display the principle with a personal computer. Using this system, students are expected to easily understand the stereographic projection.

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