1. A comparative study for assessing the influence of controls on large-scale fluvial architecture
Luca Colombera, Nigel P. Mountney, William D. McCaffrey
Fluvial & Eolian Research Group – University of Leeds

2. Overview
Creation of a relational database for the digitization of fluvial sedimentary architecture:
the Fluvial Architecture Knowledge Transfer System (FAKTS)
Quantitative characterization of fluvial architecture applicable to:
quantitative physical-stratigraphy studies
develop quantitative synthetic depositional models
derive constraints on subsurface predictions
identify modern and ancient reservoir analogues

3. Approach to DB design FAKTS conceptual and logical schemes
The sedimentary and geomorphic architecture of preserved ancient successions and modern rivers is translated into the database schema by subdividing it into geological objects – common to the stratigraphic and geomorphic realms – which belong to different scales of observation nested in a hierarchical fashion.
FAKTS conceptual and logical schemes
after Colombera et al. (2012)

4. Data definition – entry – classification
Method
Data definition – entry – classification
Segmentation of fluvial architecture into geometrically-defined channel-complex and floodplain depositional elements.
Channel-complexes are distinguished on the basis of criteria based on the recognition of geometrical changes and interdigitation of floodplain deposits – geologically-significant surfaces can also be considered.
Floodplain elements are then defined as geometrical packages laterally or vertically neighbouring channel complexes.
Kjemperud et al. (2008)
Labourdette (2011)

5. Method LIMITATIONS common lack of 3D control;
source works having variable cut-offs of size of smallest mappable units;
necessity to include also summary data (e.g. channel-complex W/T scatterplot);
simplistic qualitative classification in proximal- distal framework;
subset attributes referring to average conditions through time, even over different time scales.
Kjemperud et al. (2008)
Labourdette (2011)

6. Architectural characterization
DATABASE OUTPUT
GEOMETRIES
PROPORTIONS
TRANSITIONS
Output applied to study of:
stacking patterns
static connectivity
channel spacing

7. COMPARATIVE STUDIES OF ARCHITECTURAL STYLES
Architectural characterization
COMPARATIVE STUDIES OF ARCHITECTURAL STYLES
Example channel-complex geometrical characterization of individual FAKTS case studies:
width
thickness
W/T aspect ratio

8. Aggradation rates and stacking patterns
Applications/1
Aggradation rates and stacking patterns
Bridge & Leeder (1979)
Dalrymple (2001)
Bryant et al. (1995)
Wright & Marriott (1993)
Assessing the role of basin-wide aggradation rate as a control on fluvial architecture and as predictor of channel connectivity

9. Aggradation rates and stacking patterns
Applications/1
Aggradation rates and stacking patterns
AR vs. cT
Pearson r = 0.90
Results do not support the LAB
model of fluvial architecture

10. BASIN CLIMATE and CHANNEL-BODY GEOMETRIES
Applications/2
BASIN CLIMATE and CHANNEL-BODY GEOMETRIES
Investigation of: (i) channel-complex geometries for different basin climate types and (ii) geometrical changes in response to relative variations in basin humidity
After Tooth (2000)

11. SIGNATURE OF CHANNEL PATTERNS
Applications/3
SIGNATURE OF CHANNEL PATTERNS

12. SIGNATURE OF DRAINAGE PATTERNS
Applications/4
SIGNATURE OF DRAINAGE PATTERNS
Fielding et al. (2012)
Information on proximal to distal evolution still necessitates data from several systems for comparison.

13. Conclusions The FAKTS database permits quantitative comparative
studies of large-scale fluvial architecture applicable to the
determination of the signature of controlling factors and system variables on channel and floodplain organization;
Other FAKTS applications include:
the development of quantitative facies models;
the derivation of constraints on borehole correlations;
the derivation of constraints on stochastic simulations of fluvial architecture;
the identification of modern and ancient reservoir analogues;
the comparison of the geomorphic organization of modern rivers with preserved stratigraphic architecture.

14. Thank you for your attention
We thank our sponsors