Deep Exploration in Larderello Field: Sasso 22 Drilling Venture

  • G. Bertini
  • A. Giovannoni
  • G. C. Stefani
  • G. Gianelli
  • M. Puxeddu
  • P. Squarci

Abstract

Sasso 22 well was programmed in the Larderello field (Italy)with the objective of verifying whether geothermal fluids could be recovered from the deep horizons underlying those producing at present; other objectives were to obtain better estimates of deep energy reserves and gather information on their exploitation potential. Furthermore, data from this deep well should improve the phenomenological model of the field. Further information has been obtained on the stratigraphy of the deep layers of the crystalline basement; below 2500 m the well penetrated gneiss and amphibolite, with a gradually increasing metamorphism. In-hole logs revealed the presence of many fractured horizons within the basement down to well-bottom and increasing temperature values to around 380°C at 3970 m. Study of the parageneses indicates the existence of an initial hydrothermal phase at temperatures well above those measured at present and also of fluid circulations in unexploited sections of the basement as deep as 3–4 km.

Keywords

Sandstone Drilling Jurassic Stratigraphy Eocene 

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Copyright information

© ECSC, EEC, EAEC, Brussels and Luxembourg 1980

Authors and Affiliations

  • G. Bertini
    • 1
  • A. Giovannoni
    • 1
  • G. C. Stefani
    • 1
  • G. Gianelli
    • 2
  • M. Puxeddu
    • 2
  • P. Squarci
    • 2
  1. 1.ENEL- Unità Nazionale GeotermicaPisaItaly
  2. 2.CNR-Istituto Internazionale per le Ricerche GeotermichePisaItaly

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