A calculation procedure which makes it possible to test any kind of dating data obtained by the grain by grain method is presented. The expected age frequency distribution for Mineral grains whose size and uranium content are variable can be calculated if the fission tracks counted are assumed to have Poisson distribution. The Chi-square test between the expected and the acutual age histograms provides the precision indexthat is defined to be a hundred times the upper probability integrals and ranges from 0 to 100.

View full abstract

A routine for interactive operations among values of components in geochemical data has been established. The most striking merit of this program is that polynominal operations incluing logarithmic and exponential ones are easily performed without any modificaton of the program segments. All the user has to do is input the arithmetic expression of components in the form of string data. He can get the result soon even if he has no idea on programming for the computation. The operation-code method thought out by the writer is applied to this program. A given arithmetic expression will be translated into an operation code. It is a simplified form of the arithmetic expression. In the operation code all variables and constants are expressed as ‘X’ common and natural logarithmic functions ‘L’, and ‘N’, respectedly. Operators are written as they are. For example:
2LOG (MgO/T.FeO)
will lead an operation code to
X*L (X/ (X+X) ) .
This case shows several unique functions of the routine: The abbreviated multiplication signs are automatically inserted between terms of the code. Since T.FeO is defined in this program as total FeO, and T.Fe₂O₃ as total Fe₂O₃, they are divided into two variables, Fe₂O₃ and FeO. A pair of parentheses are added in the operation code. In this manner the values of Fe₂O₃ and FeO take part in operations as if they were one component after being recalculated into total Fe₂O₃, or total FeO.
The operation code written in a string variable is read character by character in the course of performing operations. Each character of it controls computation on exponentiation, logarithms, multiplication, division, addition, and subtraction, in accordance with the procedures for the computation defined by the characters. A simple calculation can be done in a moment because the operation code is short, while complicated operations are also easily performed.
The method is so simple that the program is only 3.4 kilobytes long including the steps for creating and checking the operation code. Therefore even small personal computers can load this routine. It is capable of maximum 10 terms and up to fivefold parentheses in a polynominal expression. These restrictions, however, depend only on the dimensions of related variable arrays so that they can be increased, if necessary, without any modification of other program steps.
The routine would play the important part of studies on geochemical data analyses with trial and errors if it is built in a program system.

View full abstract

A program on CIPW normative calculation for hand-held type personal computers with small memory sizes is given in this paper. Although it is compact and only 3.7 kilobytes long including input and output steps, the program keeps level with the routine of normative calculation in the GEOCAPS (YOSHII and SATO, 1983) : It accepts the data of ultramafic rocks with Cr₂O₃ and NiO components, and covers all range of the normative calculation from quartz through kaliophylite.
Lists and flowcharts of the program are shown in this text. Test data for CIPW normative calculation programs originated by YOSHII and HIRANO (1977) and revised by the writer are also listed for debugging them.
Since it is written in BASIC by the Microsoft Campany, the program is able to be run at least by such the following computers without any modification of the segments: the NEC PC-series and N-5200, and the Fujitsu FM-series.

View full abstract

This paper describes an attempt to make Data Base on rock and fossil specimens in Nagoya University Museum, by utilizing a handy Data Base Management System ‘YAWL’. The input data format of ‘YAWL’ is as follows;
AUTHOR (YEAR) TITLE/MAGAZINE/KEYWORD/WHY
The maximum 900 alphanumeric and Japanese kana letters are allowed to put in, throughout the above six items, only with partition marks (parenthesis and slash) .
According to the data structure of rock and fossil specimen, it is undertaken to use the six items in the following way;
AUTHOR: Sample No. and Name of Region
YEAR: (year)
TITLE: Name of Sample, Horizon, ……
MAGAZINE: Name of Locality, Date of excavation, ……
KEYWORD: Person's Name, Memo, ……
WHY: Data Package, Deposition Place, ……
Underlines indicate an essential part of information concerned. This work has just started in Nagoya University Museum, still here remain many things to be discussed. Establishment of the network system for excange of these data among several museums will be inevitable.

View full abstract

In Niigata Plain, so-called Alluvial deposits are subdivided into two formations, namely the Shirone Formation ( Late Pleistocene ) and the Holocene Higashi-Niigata Formation ( Kurotori Formation ) in ascending order. The relationships between the geological age and the soil enginnering properties of so-called Alluvial deposits are investigated. As a results, the relation between void ratio (e) and liquid limit (wL) of silty and clayey deposits shows significant difference ( Fig. 6 ) and following discriminant is obtained.
Z=1.846e-4.048log₁₀ WL+4.599
Comparison of the results of subdivision of so-called Alluvial deposits by this discrimant with the results by stratigraphical method shows more than 80% of them corresponded well together. And the application of this discriminant to Database system of ground geology is discussed.

View full abstract

In this paper, we presented the principles and the BASIC program for three-dimensional representations of grid data on the screen of the personal computer. The program draws four types of diagrams by means of (1) needle, (2) wall, (3) skelton, and (4) tile methods. The principles will be easily understood by running the BASIC program and watching how each diagram is drawn.

View full abstract

According to the so-called Busk method, folding structures in geological sections can be reconstructed graphically by hand work. In this paper, the geometrical principles of the Busk method for drawing bedding planes were described in the manner of analytical geometry. The descriptions enable us to analyze folding structures numerically by computer without hand work. As an example, we presented the BASIC program which draws bedding planes automatically on the screen of the personal computer.

View full abstract

In this paper, we discussed the computerized method to draw a folding structure in a geological section based on the assumption that the dip angle is constant in the vertical direction. The assumption indicates the similar folding, and is different from the Busk's one of the parallel folding. If observed dip angles are interpolated linearly, we can express the forms of bedding planes by analytical functions. Further, if we have locational coordinates of the outcrops on a particular bedding plane, we can define the form of the bedding plane which passes through the outcrops. This method is simple in the mathematical treatise, and is suitable for computer processing more than the Busk method. We presented the BASIC program which draws one bedding plane on the screen of the personal computer, based on this method.

View full abstract

Reconstraction of folding structures in geological section is mathematically identical to solving differential equation: sin θ dx + cos θ dy =0, where θ is the dip angle. If we can interpolate either scalar values or vectors (sin θ, cos θ) at any points (x, y) from observed dip angles, we can solve the differential equation numerically to reconstract folding structures. In this paper, we discussed the computerized method to draw folding structures by interpolating vectors (sin θ, cos θ ) from weighted means of the observed ones, and presented its BASIC program. This method is suitable for computer processing of the folding structure in the area where we can obtain dip angles at a lot of places scattering at random vertically as well as horizontally.

View full abstract