Functioning of an ancient routing system, the Escanilla Formation, South Central Pyrenees
Author(s)
Michael, Nikolaos
Type
Thesis
Abstract
The thesis topic concerns the analysis of a well-exposed Eocene sediment routing system in the
wedge-top zone of the southern Pyrenees. The Escanilla sediment routing system can be used as a
case study of generic value in understanding the dynamics of an ancient source-to-sink system. The
Escanilla Formation is a mid-upper Eocene (Bartonian – Priabonian) siliciclastic sedimentary system
that was sourced from the Axial Zone of the Pyrenees and deposited on top of the fold-thrust belt of
the south-central tectonic unit. Its deposits are found in the Tremp-Graus and Ainsa basins and distal
time equivalent units are found in the Jaca basin.
The project involves the definition of the sediment routing system linking source area catchments and
depositional sinks. It investigates the provenance of sediment in the basin-fill, tracks down-system
sedimentological and granulometric trends, and evaluates the volumetric budget of the entire sediment
routing system.
The reconstruction of the sediment routing system fairway was aided by new provenance data
comprising U/Pb dating of detrital zircons, detrital apatite fission track analysis, and evaluation of
clast lithologies in fluvial conglomerates, compilation of palaeoflow indicators from sedimentary
structures, and a pilot study of heavy minerals.
A correlation panel is proposed dividing the Escanilla system into three time intervals. Sedimentary
facies changes, grain-size of conglomerate and grain-size fractions are analysed quantitatively from
proximal to distal stations within these three time intervals. The fairway, combined with sedimentary
logs, allows a sediment budget to be constructed. Depositional volumes and surface fluxes are
calculated for the three time intervals, allowing the temporal evolution of the sediment routing system
to be constrained. Knowledge of the evolution of sediment budgets and fluxes through time allows an
assessment of the sediment effluxes of catchment areas feeding the Escanilla system, and helps an
understanding of how supply signals (grain-size fractions and sediment volumes) are propagated
down-system. Such propagation is a vital tool in stratigraphic prediction.
wedge-top zone of the southern Pyrenees. The Escanilla sediment routing system can be used as a
case study of generic value in understanding the dynamics of an ancient source-to-sink system. The
Escanilla Formation is a mid-upper Eocene (Bartonian – Priabonian) siliciclastic sedimentary system
that was sourced from the Axial Zone of the Pyrenees and deposited on top of the fold-thrust belt of
the south-central tectonic unit. Its deposits are found in the Tremp-Graus and Ainsa basins and distal
time equivalent units are found in the Jaca basin.
The project involves the definition of the sediment routing system linking source area catchments and
depositional sinks. It investigates the provenance of sediment in the basin-fill, tracks down-system
sedimentological and granulometric trends, and evaluates the volumetric budget of the entire sediment
routing system.
The reconstruction of the sediment routing system fairway was aided by new provenance data
comprising U/Pb dating of detrital zircons, detrital apatite fission track analysis, and evaluation of
clast lithologies in fluvial conglomerates, compilation of palaeoflow indicators from sedimentary
structures, and a pilot study of heavy minerals.
A correlation panel is proposed dividing the Escanilla system into three time intervals. Sedimentary
facies changes, grain-size of conglomerate and grain-size fractions are analysed quantitatively from
proximal to distal stations within these three time intervals. The fairway, combined with sedimentary
logs, allows a sediment budget to be constructed. Depositional volumes and surface fluxes are
calculated for the three time intervals, allowing the temporal evolution of the sediment routing system
to be constrained. Knowledge of the evolution of sediment budgets and fluxes through time allows an
assessment of the sediment effluxes of catchment areas feeding the Escanilla system, and helps an
understanding of how supply signals (grain-size fractions and sediment volumes) are propagated
down-system. Such propagation is a vital tool in stratigraphic prediction.
Version
Open Access
Date Issued
2013-03
Date Awarded
2013-07
Copyright Statement
Attribution NoDerivatives 4.0 International Licence (CC BY-ND)
Advisor
Allen, Philip
Publisher Department
Earth Science and Engineering
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)