The developing cyberinfrastructure affects the knowledge system by which geological surveys collect, represent, and communicate their knowledge, and thereby influences their view of the geology. Consequences for four interacting aspects of the overall system (infrastructure, business models, geological framework, and surveying methods) are outlined. Although each reflects a different area of expertise, all aspects must work together to support an incipient change of emphasis in survey work -from publishing maps and supporting documents, to contributing to a whole-Earth knowledge system that responds flexibly to user needs.

Consideration of an explicit systems framework for geological survey information is timely, to assist in developing and maintaining an integrated and coherent view of regional geoscience in a Grid-based context. A framework based on a solid Earth systems model is tentatively proposed in this paper. The developing advanced infrastructure of information and communications technology, the so-called Grid, points to more flexible global communication that will help to overcome artificial boundaries and divergence of concepts from separate places and scientific disciplines. Interoperability of information (the ability to amalgamate and work with concepts, terms or models from various sources, and thereby share and reuse information) will be a key to the Grid's success. Geological surveys can respond to the opportunity by changing their emphasis, away from publishing printed maps and related documents, towards maintaining a geoscience knowledge system from which scientific workflows can provide flexible services that match requirements specified by the user. The changing system should fit with, and build upon, existing patterns of human thought and the published record; include interpretation as an essential part of the conceptual building blocks that support geologists as they abstract, codify and reason, link observation to explanation, and predict what they have not yet observed; support improved representations of the geology; and encourage the use of generic concepts and ontologies, following international standards where appropriate.

-Information technology can lead to more efficient, versatile and less costly ways of supplying and using information. The familiar paper journals and books of the geoscience literature are being supplemented, and some supplanted, by electronic versions offering new facilities. Geoscience repositories gain efficiency and flexibility in storage, management, access and presentation of data. Global standards help communication, sharing of facilities, integration of ideas, collaboration and delegation of decisions. An example from geological mapping illustrates how a broad view of computer methods leads, not just to better ways of delivering the same product, but to more fundamental improvements in expressing, sharing and generalizing the geologists' conceptual models. Familiarity with existing systems can blind us to their shortcomings: familiar methods may hide assumptions that are no longer relevant. The example suggests that maps, reports and supporting evidence can be linked by hypertext in a tightly connected model. Targeted distribution of appropriate, up-todate information can replace the high-cost scattergun approach of conventional publication. This leads to a tentative identification of user needs.

-We need a strategy to cope with fundamental changes in our ways of working, based on a clear view of what we do and why. A systems view is essential to relate each part to the whole. This model of the geoscience information system should take into account: the need to separate data and process to enable reuse; the modes of thought of the geoscientist and how memory orders our thoughts; the shared geoscience record (knowledge base) and its interface with users; how ideas are linked as a network; how knowledge is organized; how a general overview can be maintained and linked to detail; how projects relate business objectives to the knowledge base and incentives keep the system alive.

-Information technology deals with tools for handling information, notably computers and networks. It brings benefits such as more efficient and rigorous formulation and expression of ideas, and wider sharing and integration of knowledge. This review should help practicing geoscientists and students to gain a broader understanding of these changes and form a view on future trends.Key Words -Information technology, metainformation. Defining Information TechnologyGeoscience after IT, published as a book and a special issue of Computers & Geosciences, offers a broad overview of the impact of information technology on the work of geoscientists, seen against the background of evolving global communication on the Internet.Information technology (IT) refers to methods of handling information by automatic means, including computing, telecommunications and office systems. It deals with a wide range of mostly electronic devices for collecting, storing, manipulating, communicating and displaying information. Examples of IT devices are: computer software and hardware, including memory and disk storage; printers; the telephone, cable, broadcasting and computer networks; office copiers; facsimile (fax) machines; DVDs; video cameras; image scanners; televisions and monitors; data loggers and automated instruments in the field and laboratory; sensors on satellite cameras or downhole logging tools; digital surveying equipment.IT applications seldom respect disciplinary boundaries. The focus here is geoscience, centered on geology but inevitably overlapping into such subjects as geophysics, geochemistry, economic geology, engineering geology, and soil science. I occasionally stray into related aspects of environmental science, surveying and geomorphology, but try to steer clear of such topics as hydrology, meteorology or oceanography, which may be parts of the Earth Sciences in the wide sense, but are well covered in their own specialized publications.