All geological investigations are used in the definite succession in the time and space. For this different geological means are employed (mining works, drilling, geophysical and geochemical investigations, etc). The final expected aim of geological prospecting is the best recognition of studied area by given limitations. Effectiveness of geological mean application is based on three factors: cost, time and informational criterions. Cost and time criterions maybe estimated by simple calculation, but determination of last criterion is a complicated problem. Informational criterion model is composing from three factors: (1) quantitative estimation of information, (2) estimation of informational reliability and (3) estimation of informational value by degree of aim achievement according to the pragmatic criterion. The main aim of the paper is a problem of determination of set of means composing the notion "geological prospecting" (relative to some fixed feature) by assumed reliabilities of the means. The reliability of geological prospecting means is considered at the level of local determination. Reliabilities of information obtaining by separate mean and set of means are analyzed in detail. Suggested procedure of determining reliability for means and sets of means relative to feature is based on improved methodology of conditional probability utilization. The ways providing the increment of reliability of geological means are proposed. The applicability of proposed methods is shown on simplified examples. Utilization of the methods will allow to finding the most optimal combinations of geological means in different physical-geological conditions.

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In underground construction projects such as radio activate waste disposal facilities, clarification of the rock failure mechanism is an important, though difficult task. Although many informative studies have been published on this topic, additional research is needed to help keep these structures stable for many years. In this study, microcracks were firstly identified by the fluorescent method and next classified in detail in order to analyze the relationships and processes in crack growth and junction. That is, microcracks are classified into three kinds of cracks: intracrystalline cracks, intercrystalline cracks and grain boundary cracks. In spite of the complicated features of cracks, these detailed classifications became possible by image processing.
Observed crack directions and length (total length / mm²) became more characteristic as lateral strain increased especially in post-failure specimens. At first, the number of intracrystalline cracks and grain boundary cracks increased slowly, and intercrystalline cracks did not increase much. Intercrystalline cracks, however, increased in number around junctions and rapidly increased after junction in the typical three directions and in total length. On the other hand, intracrystalline cracks and grain boundary cracks almost stopped growing after junction. Thus, we found that intercrystalline cracks have a quite important role in the sharing process, although they are less numerous than other crack types.
Because of the complicated images, fractal dimensions were also measured by box counting method in these stages. Though intracrystalline cracks and grain boundary cracks showed almost the same fractal dimensions throughout the failure process, intercrystalline cracks increased in number especially in post-failure specimens, suggesting intercrystalline cracks have an important role in the failure process. In fractal dimensions, the same trends were seen.

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Description of the outcrop is important in the geological survey. The arrangement of the observation result becomes a big burden as the survey goes on. For this reason, it is desirable that database has not only outcrop lists but also have functions which construct the geological structure of the investigation area from outcrop.
The author propose the stratigraphical graph and the stratigraphical formula as the descriptive method of outcrop data on the outcrop database. A directed labeled graph is applied to this graph;, vertexes of the graph correspond to layers and arcs of the graph correspond to the contact relations. Each arc of the graph connects from the lower layer to upper layer. The label of vertex is the layer name, and the label of arc is the name of contact relation. The name of the layer and the contact relation are related to the description of the layer and the contact relation under the binary relation respectively.
The stratigraphical formula expresses the stratigraphical graph with a set form: This formula expresses the contact relation of the two layers with the form (lower layer unit)(relation unit)(upper layer unit), where layer units are represented by layer names and contact units are by symbols. With this formula, we are able to express the data outcrop data uniformly, including the case that boundary of layers is unknown and the case that the condition of boundary is estimated from neighboring outcrops. The stratigraphy of the investigation area can be established through operation of the stratigraphical formulae of outcrop. The author proposed the algorithm of this operation.

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