The organisation of access to data bases of the thesauruses and classification schemas (DBTCS) under the protocol Z39.50 in a preferred schemat Zthes, intended for navigating under the thesauruses is considered. The dignities of this approach are discussed at construction of the distributed information systems of general purpose. The decision UIGGM SB RAS is resulted within the framework of the distributed library informational system. This system is based on multi-platform modular servers Z39.50 ZooPARK (development UIGGM SB RAS) and gateways of Z39.50-WWW. The system contains a plenty (more than 10 000 000 Records) bibliographic and analytical information of a wide spectrum stored in various data bases (DB) on various servers. The access to all information system is realised both under the protocol Z39.50, and through WEB. In the report is exhibited, that:

• the application of the protocol Z39.50 for access to DBTCS is given rich possibilities for construction of the distributed information systems - by integration DBTCS and DB with maintenance of uniform network access under the standard global circuits;

• usage of preferred circuits of the data allows to hide private(individual) discrepancies of structures various DBTCS and to supply the uniform interface without rebuilding;

• in the distributed systems it is possible and it is necessary to organise of a specialised server for a storage DBTCS with granting to them of access on Z39.50;

• at construction of concrete bibliographic DB follows as it is possible more widely to use binding of records to the various thesauruses and classification circuits. The absence of this information in a DB excludes last from uniform information space in the distributed information system.

• the global circuit Zthes requires(demands) expansion for an adequate information display DBTCS.

Oleg L. Zhizhimov - Head of Sector of Information Technology of the United Institute Of Geology, Geophysics And Mineralogy of the Siberian Branch of RAS.

Nikolay A. Mazov - Head of Centre for Information and Reference Services of the United Institute of Geology, Geophysics and Mineralogy of the Siberian Branch of RAS.