Abstract
Tectonic forces generated during thrust emplacement along active margins may drive complex fluid-flow patterns in fold-thrust belts and foreland basins. Isotope data (d2Hand d18O) of fluid inclusions hosted in calcite vein cements are used to reconstruct regional fluid migration pathways in the Albanide fold-thrust system. The calcite veins used in this study developed in a sequence of naturally fractured Cretaceous-Eocene carbonate rocks as a result of episodic throughput of fluids fromthe early stages of burial onward. The acquired fluid inclusion isotope data demonstrate that fluids circulating in the carbonates were derived from an underlying reservoir that consisted of a mixture of meteoric water and evolved marine fluids, probably derived from deep-seated evaporites. The meteoric fluids infiltrated in the hinterland before being driven outward into the foreland basin and ascended as soon as fracturing induced a sufficient increase in permeability. Structural and petrographic observations provide time constraints for the various phases of fracture infilling and reveal an increasing dominance of meteoric water in the system through time as migration pathways shortened and marine formation fluids were progressively flushed out. Similar fluid-flow evolutions have previously been recorded in various fold-thrust belt settings elsewhere in the world.
| Original language | English |
|---|---|
| Pages (from-to) | 2421-2445 |
| Number of pages | 25 |
| Journal | AAPG Bulletin |
| Volume | 103 |
| Issue number | 10 |
| DOIs | |
| Publication status | Published - Oct 2019 |
Funding
We are grateful to Suzan Verdegaal for technical support in the laboratory at VU Amsterdam. We thank Bouke Lacet for manufacturing thin sections. Sébastien Peter of Olympus Europa SE & Co. KG (Hamburg, Germany) is thanked for facilitating our petrographic analysis by confocal laser scanning microscopy. L. Siebenaller and two anonymous reviewers are thanked for their constructive comments for improving the manuscript. This study was sponsored by the CPG-KFUPM (Dhahran, KSA). This is CPG contribution no. 26.
