Fault database for the George and NE Edward Rifts, Uganda

This database is associated with a master's research project at the University of Bristol. The initial geospatial database documents the geometry of 152 faults identified through digital mapping, along with associated attributes. This represents the first detailed fault mapping conducted in the area. The version of record is in .geojson format, however data is also available in .kmz and .shp formats. Attributes are adapted from Williams et al. (2022) and the Global Earthquake Model Global Active Faults Database (GEM-GAFD; Styron & Pagani, 2020).

List and brief description of the attributes in the fault database ('EGR_faults')

Attribute
Data Type
Description
Notes

FAULT_ID
integer
Unique numerical reference ID

CONFIDENCE
integer
Certainty of whether the fault exists there
1 = moderate, 2 = high

FAULT_NAME
string
Name of fault
Not all faults are named. Assigned based on previous mapping or local geographic features.

DIP_DIR
string
Compass quadrant of fault dip direction

NOTES
string
Remaining miscellaneous information about the fault
e.g. cross-cutting, segmentation, channel incision.

LENGTH_TT
integer
Tip-to-tip fault length

MAX_GRAD
real number
Estimated maximum gradient of scarp
Calculated by taking fault-normal topographic profile at steepest gradient indicated by slope map.

LENGTH
real number
Along-trace fault length

Fault-normal topographic profiles were then used to measure scarp heights for 130 of the 152 mapped faults. The resulting displacement-length data for each fault is documented in 'slip_profile_data.zip'. A summary of the analysis of fault slip (displacement-length) profiles is outlined in 'EGR_slip_profiles_summary.xlsx'.

List and brief description of the attributes in the slip profile summary ('EGR_slip_profiles_summary')

Attribute
Description
Notes

Fault ID
Unique numerical reference ID

Length
Along-trace fault length
To nearest 100m

Dmax
Maximum measured displacement along fault scarp

Dmax/L
Maximum displacement divided by fault length

Profile type
First order shape of slip profile
Following classifications outlined by Manighetti et al. (2001):

L = linear

HR = half-restricted

TR = tip-restricted

DTR1 = both tips restricted, symmetrical

DTR2 = both tips restricted, asymmetric

DTR3 = half-restricted and tip-restricted

QE = quasi-elliptical

ET = elliptical with tapers

U = unclear/intermediate pattern

Dominant propagation direction
Direction that fault is preferentially propagating in
For unilaterally-propagating faults (tip- or half-restricted) as well as DTR and elliptical-with-taper faults that show a strong sense of preferred propagation

Clarity rating
How well profile is fit by first-order shape

1 - profile clearly fit by first order shape

2 - first order shape with moderate smaller-scale peturbations

3 - first order shape determined with some difficultly, may be obscured by segmentation, channel incision etc. 

4 - profile not fit by any first order shape, or intermediate, or impossible to differentiate

Segments
Estimated number of segments that fault is formed from
Interpreted from displacement minima and mapping observations.

Notes
Remaining miscellaneous information about the fault
e.g. channel incision, anomalous topographic features