Download ONTOLOGICAL REPRESENTATION OF RIFTS

ONTOLOGICAL
REPRESENTATION
OF RIFTS
Arijit Mitra and A.K. Sinha
Department of Geosciences
Virginia Tech
RIFTS
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Rifts are fault-bounded elongate troughs,
under or near which the entire thickness of
the lithosphere has been reduced by
extension during their formation.

Rifts form in many tectonic settings such as
above mantle plumes and at all stages of the
Wilson Cycle.
Significance of Rifts

Rifting of continents involves two principal geological
processes - tectonism and magmatism, which reflect
the strain-rate and temperature dependent processes of
deformation and adiabatic decompression melting
within the earth.

Continental extension and break up are fundamental to
understanding the origin of ocean basins and the
mechanics of plate tectonics - all ocean basins form as
a result of continental extension.
Significance of Rifts

The fundamental geological processes that cause crustal
extension - mantle convection, mantle plumes, opposing forces
from slab pull and ridge push, and gravitational collapse.

Hence, the study of rifts will enable us to determine
- the original local and regional states of stress
- the spatial and temporal distribution and rate of strain
- the pressures and temperatures
- the physical and chemical properties of rocks and fluids
involved
- heterogeneity of the continental lithosphere prior to rifting
- the pattern of mantle flow
- the extent & style of melt generation & emplacement
ONTOLOGY for RIFTS
Reference:
Sengor & Natal’in, 2001
RIFT-RELATED ROCKS IN THE
MID-ATLANTIC TEST BED

Two main phases of rifting (extension) in the Appalachians

Cryogenian Magmatic Province
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Catoctin Volcanic Province
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760 Ma
failed rifting event
divergent plate boundary rift without previous doming (k22)
570 Ma
rifting event that led to the formation of Iapetus ocean & break-up of
Rodinia
divergent plate boundary rift without previous doming (k22)
Geological data from these two geological provinces are
part of the VIRGINIA TECH IGNEOUS ROCK
DATABASE
GLOBAL DATABASES ON
EXTENSION RELATED ROCKS
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GEOROC
NAVDAT
PETDB
PETROS
USGS DDS 14 Geochronology Database
EarthRef
Conclusion

Integration of the above-mentioned databases
and web-based access through high
performance computing is envisioned as part
of the GEON cyberinfrastructure initiative.

An ontology driven integration is vital since
ontologies are used as a computational pathway
for answering queries.
Conclusion

A spatial and temporal comparison of geological provinces
improves our understanding of geological processes
and provides fundamental information on the physical
and chemical evolution of continents through time.

Rift environments represent continental-scale processes
that involve extrusion of igneous rocks, evolution of
sedimentary basins, extensional/compressive tectonism to
metamorphism and leave a geophysical signature.

An ontological linking and integration of these
multidisciplinary datasets will improve our
understanding of complex dynamics of Earth