Malawi Active Fault Database - MAFD

The Malawi Active Fault Database (MAFD) is a freely available open-source geospatial database of active fault traces within Malawi. The database is intended to cover all active faults within Malawi, and those close to the borders in Mozambique and Tanzania. However, possible active faults within 20 km of Malawi in the Luangwa Rift, eastern Zambia, and the Rukwa Rift, southern Tanzania, are not included in the MAFD.

Citation

Please cite the following two references if using this database: Williams, J. N., Wedmore, L. N. J., Scholz, C. A., Kolawole, F., Wright, L. J. M., Shillington, D., Fagereng, Å., Biggs, J., Mdala, H., Dulanya, Z., Mphepo, F., Chindandali, P. R. N., Werner, M. J. (2022), The Malawi Active Fault Database: an onshore-offshore database for regional assessment of seismic hazard and tectonic evoultion. Geochemistry, Geophysics, Geosystems, 23(5), e2022GC010425. https://doi.org/10.1029/2022GC010425

Williams, J. N., Wedmore, L. N. J., Scholz, C. A., Kolawole, F., Wright, L. J. M., Shillington, D., Fagereng, Å., Biggs, J., Mdala, H., Dulanya, Z., Mphepo, F., Chindandali, P. R. N., Werner, M. J. (2021), Malawi Active Fault Database. [Data set]. Zenodo. https://doi.org/10.5281/zenodo.5507189

Data Format

The MAFD is a geospatial database containing a collection of active fault traces in GIS vector format. Each faults is mapped as a single continuous GIS feature, including those that show branching geometries. Each fault trace has associated metadata that describe the geometry of the faults, and various aspects of its exposure. Note all faults in this database are considered to have normal kinematics.

Data Table

Attribute	Data Type	Description	Notes
MAFD-ID	integer	Unique tree-digit numerical reference ID
fault_name	string		Assigned based on previous mapping or local geographic feature
dip_dir	string	Compass quadrant of fault dip direction
slip_type	string	Kinematic type	All faults in the MAFD show normal offsets and so are inferred to be predominantly normal but we cannot discount that some faults also exhibit an oblique-slip component.
GeomorphEx	string	Geomorphic expression of the feature used to identify and map the fault trace	scarp, escarpment
LocationM	string	Dataset used to map the fault trace	Type of digital elevation model or other geophysical dataset
accuracy	integer	Coarsest scale at which fault trace can be mapped. Expressed as the denominator of the map scale	Reflects the prominence of the fault's geomorphic expression
ActivConf	integer	Activity Confidence: Certainty of neotectonic activity	1 if certain, 2 if uncertain
ExposQual	integer	Exposure Quality of the fault	1 if high, 2 if low
EpistQual	integer	Epistemic Quality - certainty of whether that fault exists there	1 if high, 2 if low
Last_Mov	string	Date of last earthquake on the fault	Currently this is unknown for all faults in Malawi except the St Mary’s Fault.
Notes	string	remaining miscellaneous information about the fault
References	string	Relevant geological maps and literature where the fault has previously been described

List and brief description of the attributes in the MAFD. Attributes are based on the Global Earthquake Model Global Active Faults Database (GEM-GAFD; Styron and Pagani, 2020). Note, currently we do not include all attributes from the GEM-GAFD as these data have not been collected in Malawi. It is the intention that future versions of this database will include more attributes (e.g. slip rates). No assessment is made of the seismogenic properties of faults in the MAFD as this is subjective and liable to change, therefore, these data have been stored in a separate database that will shortly be submitted for publication.

File Formats

Following the GEM-GAFD this database is provided in a variety of GIS vector file formats. GeoJSON is the version of record, and any changes should be made in this version before they are converted to other file formats using the script in the repository that uses the GDAL tool ogr2ogr (the script is adapted from https://github.com/cossatot/central_am_carib_faults/blob/master/convert.sh - we thank Richard Styron for making this publicly available). The other versions available are ESRI ShapeFile, KML, GMT, and GeoPackage.

Version Control

A "static version" of this database in all file formats described above and associated with the submission in G^3 is available on Zenodo at the following link:

This version is intended to be "Live" and as such we encourage edits of the GeoJSON file and the submission of pull requests. Please contact Jack Williams [email protected] Luke Wedmore [email protected] or Hassan Mdala [email protected] for information, other requests or if you find any errors within the database.

Malawi Other Faults Database (MOFD)

The Malawi Other Faults Database (MOFD) is a geospatial database of other faults in Malawi that have been identified in geological maps, aeromagnetic and gravity datasets, and/or on fieldwork where we did not find any evidence of activity as outlined in the manuscript associated with this database. The database is structured slightly differently from the MAFD and has the following attributes.

Attribute	Data Type	Description	Notes
MOFD_ID	integer	Unique numerical reference ID
Fault_Name	string
Fault_Age	string	Age of last activity on the fault
slip_sense	string	kinematic type of fault	e.g. normal, reverse, strike-slip (dextral or sinestral)
Notes	string	information about offset/geology and other evidence for the existence of the fault
References	string	references associated with the fault

References

Styron, Richard, and Marco Pagani. “The GEM Global Active Faults Database.” Earthquake Spectra, vol. 36, no. 1_suppl, Oct. 2020, pp. 160–180, doi:10.1177/8755293020944182.