A global spring carbonate GIS database in tectonically active settings

Spring carbonates are widespread in tectonically active settings, especially in rift systems, and potentially form pre-salt reservoirs in the South Atlantic. Spring carbonates have been studied for more than a century, and there are amounts of published data on the facies, depositional processes and water chemistry of associated springs. However, the literature is widely scattered and frequently difficult to access. GIS (Geographic Information System) technology can be used to gather all information together by 1) cataloguing the spatial characteristics of (morphology/facies and their associated springs) and 2) integrating observed images, analytical results and geological background elements into a single and standardized database.

This study has established an initial global spring carbonate GIS database, which provides a research tool to allow users to visualize and compare the spatial distribution of spring carbonates and their geometric relationships. The database also enables users to assess the relationships between: 1) spring carbonate deposition and spring chemistry; and 2) spring carbonate deposits and geological background elements (such as faults, volcanoes and limestones, with which spring carbonates are typically associated). Ultimately, the database provides a valuable resource for synthesizing and generating conceptual models.

Based on the GIS database, we conclude the following:

1. the regional settings for spring carbonate formation are mainly in rift systems, also
2. Spring carbonates are formed in subaerial and sublacustrine environments;
3. spring carbonate morphologies (megascale: 10s-100s m to km) can be

We also propose a concept of Spring Carbonate Window as an approach to predicting travertine occurrence. Travertine can start to form at the beginning of rifting and continue more or less throughout the rifting phase, such as the case in the Itaboraí Paleocene half graben of Brazil (north of the Santos Basin). In this case spring carbonates filled most of the Itaboraí Basin; however, the spring carbonate succession was interrupted by alluvial fan deposits. In the Denizli Basin of Turkey and much of the central Italy, spring carbonate deposits appear to have developed during the later stages of rifting. In these locations spring carbonate deposits form in phases and are patchy and mostly scattered along basin margins.