Impact of channelized flow on temperature distribution and fluid flow in restless calderas: Insight from Campi Flegrei caldera, Italy

Research output: Contribution to journalArticle (Academic Journal)peer-review

12 Citations (Scopus)
525 Downloads (Pure)

Abstract

Magmatic hydrothermal systems develop by the imposition of a magmatically derived heat flux upon a shallow groundwater system. As such their dynamics can be intermittently perturbed by changing conditions within the associated magmatic system. Understanding the nature of the coupling between the magmatic and groundwater systems is thus key to discriminating geophysical signals of magmatic unrest from purely hydrothermal ones.

Using a series of numerical groundwater models run with TOUGH2, we simulate the coupled groundwater–magmatic system at Campi Flegrei caldera, with particular emphasis on the impact of permeability developed within local fault systems and the dynamics of the system during magmatic unrest. Simulation results suggest that faults can play an important role in controlling the dynamics of recharge and heat transport within the shallow hydrothermal reservoir. Results specifically highlight that contrasts in permeability between faults and surrounding rock impact local temperature gradients, with faults either acting as preferential routes for recharge or discharge of groundwater, depending on fault/caldera fill permeability contrast and the vertical extent of the fault. Simulations of magmatic unrest with a step-wise increase in basal heat flux suggest that periodic geophysical and chemical signals may stem from the interaction between the development of gas at depth and the recharge–discharge dynamics of the reservoir. These results highlight the potential for the dynamics of magmatic–hydrothermal systems to be significantly impacted by the presence and nature of local fault systems. Where dynamic groundwater systems are involved, it is thus important to understand the impact of such geological elements when interpreting monitoring data such as ground deformation, seismicity and gas emissions.
Original languageEnglish
Pages (from-to)157-174
Number of pages18
JournalJournal of Volcanology and Geothermal Research
Volume303
Early online date2 Aug 2015
DOIs
Publication statusPublished - 15 Sep 2015

Bibliographical note

Date of Acceptance: 02/08/2015

Keywords

  • Campi Flegrei caldera
  • Unrest
  • Numerical modelling
  • Hydrothermal fluid flow
  • Fault

Fingerprint Dive into the research topics of 'Impact of channelized flow on temperature distribution and fluid flow in restless calderas: Insight from Campi Flegrei caldera, Italy'. Together they form a unique fingerprint.

Cite this