Charakterystyka utworów sylurskich syneklizy perybałtyckiej na podstawie badań geofizyki wiertniczej

Abstract

W artykule przedstawiono możliwości poznania budowy geologicznej utworów sylurskich syneklizy perybałtyckiej na podstawie wyników badań geofizyki wiertniczej. Dokonano rozpoziomowania i korelacji tych utworów oraz ustalono nowy geofizyczny podział, który umożliwi m. in. określenie profilu litologiczno-stratygraficznego, również w tych otworach, gdzie brąk jest uzysku rdzenia.

THE CHARACTERISTICS OF SILURIAN ROCKS FROM THE PERIBALTIC SYNECLISE ON THE BASIS OF WELL LOGGING DATA

The paper presents zonation and correlation of Silurian rocks from the Peribaltic Syneclise on basis of well logging data. The characteristics of these rocks is mainly based on resistivity and gamma loggings. The rocks are divided into 8 geophysical complexes and several subcomplexes. Figures 1 and 2 present geophysical characteristics of complexes I-V, :F1ig. 3 - of complex VI, Figs. 4-5 - of complex VII and Fig. 6 - of complex VIII. The complex I is assigned to the Lower Llandoverian, II - to the Upper Llandoverian, III, IV and V - to the Wenlockian, and VI, VII and VIII -to the LudIovian.

Silrian rocks attain here up to 1800 m in thickness and are represented by clay deposits only. The new geophysical subdivision of these rocks, presented here, is based on lithology and paleontological records also so it will make possible establishment of lithostratigraphic profile of drillings in the case when core material is lacking.

It appears that the geophysical studies made possible to distinguish much more correlative layers within the clay Silurian profile (Figs. 1-6) than the geological methods. Special laboratory studies are necessary for more precise elucidating the causes of changes of physical parameters within the profile of clay Silurian rocks.