TY - JOUR
T1 - Faulting and fluid flow in porous rocks and sediments
T2 - Implications for mineralisation and other processes
AU - Barnicoat, Andrew C.
AU - Sheldon, Heather A.
AU - Ord, Alison
PY - 2009/5/7
Y1 - 2009/5/7
N2 - Faults in sedimentary rocks can act as fluid pathways or barriers to flow and display a range of deformation styles. These features can be explained by behaviours observed in deformation experiments on sedimentary rocks that reveal a transition from dilatant brittle faulting and permeability enhancement to cataclasis and permeability reduction, with increasing porosity, grain size and confining pressure. This transition implies that faults in sedimentary rocks are unlikely to act as fluid pathways shallower than ∼3 km, unless the sediments have undergone early cementation, or have been exposed following burial and uplift. This has important implications for many geological processes, including fluid circulation in geothermal systems, formation of sediment-hosted mineral deposits and earthquakes in subduction zones. Stratiform Zn-Pb deposits that have been interpreted as syngenetic, seafloor deposits could instead be interpreted as early epigenetic deposits representing the depth at which faults change from fluid pathways to barriers.
AB - Faults in sedimentary rocks can act as fluid pathways or barriers to flow and display a range of deformation styles. These features can be explained by behaviours observed in deformation experiments on sedimentary rocks that reveal a transition from dilatant brittle faulting and permeability enhancement to cataclasis and permeability reduction, with increasing porosity, grain size and confining pressure. This transition implies that faults in sedimentary rocks are unlikely to act as fluid pathways shallower than ∼3 km, unless the sediments have undergone early cementation, or have been exposed following burial and uplift. This has important implications for many geological processes, including fluid circulation in geothermal systems, formation of sediment-hosted mineral deposits and earthquakes in subduction zones. Stratiform Zn-Pb deposits that have been interpreted as syngenetic, seafloor deposits could instead be interpreted as early epigenetic deposits representing the depth at which faults change from fluid pathways to barriers.
KW - Faulting
KW - Fluid flow
KW - Mineralisation
KW - Permeability
UR - http://www.scopus.com/inward/record.url?scp=68249149599&partnerID=8YFLogxK
U2 - 10.1007/s00126-009-0236-4
DO - 10.1007/s00126-009-0236-4
M3 - Article
AN - SCOPUS:68249149599
VL - 44
SP - 705
EP - 718
JO - Mineralium Deposita: international journal of geology, mineralogy, and geochemistry of mineral deposits
JF - Mineralium Deposita: international journal of geology, mineralogy, and geochemistry of mineral deposits
SN - 0026-4598
IS - 6
ER -