Evolution of anastomosing crack–seal vein networks in limestones: Insight from an exhumed high-pressure cell, Jabal Shams, Oman Mountains

Holland, Marc; Urai, János L.

doi:10.1016/j.jsg.2009.04.011

Cited by 67 publications

(53 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3e). These geometries are very similar to those seen in the "zebra rocks" described by Holland and Urai (2010) in low porosity limestones in Oman. Most individual veins have an average thickness of 1-2 mm,…”

Section: Selwick Baysupporting

confidence: 79%

Fault and fracture patterns in low porosity chalk and their potential influence on sub-surface fluid flow—A case study from Flamborough Head, UK

et al. 2016

View full text Add to dashboard Cite

Section: Selwick Baysupporting

confidence: 79%

Fault and fracture patterns in low porosity chalk and their potential influence on sub-surface fluid flow—A case study from Flamborough Head, UK

et al. 2016

View full text Add to dashboard Cite

“…The patterns produced in the parallel crack seal models confirm that the relative strength of the vein controls whether the crack seal or crack jump process are active [ Ramsay , ; Caputo and Hancock , ; Holland and Urai , ]: weak veins localize fracturing inside of the veins and grow in length and aperture with every new fracturing and sealing (ataxial crack seal veins). On the contrary, veins stronger than their surrounding host rock do not reactivate.…”

Section: Discussionmentioning

confidence: 99%

“…The produced structures are, in general, in agreement with the prediction by Holland and Urai []. The strong veins, however, show a slightly higher degree of interaction than proposed in the conceptual model.…”

Section: Discussionmentioning

confidence: 99%

“…They form by repeated fracturing and sealing localizing inside the vein (syntaxial veins) or at the vein‐host rock interfaces (antitaxial veins) [ Durney and Ramsay , ; Ramsay and Huber , ; Passchier and Trouw , ]. Syntaxial vein growth can result from imperfect cementation or from a cement weaker than the host rock [ Laubach , ; Holland and Urai , ]. Antitaxial veins form by repeated fracturing of the vein interfaces and is often observed in situations where the host rock is chemically incompatible with the vein cement what results in a weak adhesion of the cement crystals to the vein walls [ Urai and Williams , ].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The evolution of crack seal vein and fracture networks in an evolving stress field: Insights from Discrete Element Models of fracture sealing

2014

Self Cite

View full text Add to dashboard Cite

Veins are ubiquitous in upper and middle crustal rocks. Due to strength and stiffness contrast to the host rock, veins can influence crack propagation. Here we present Discrete Element Models to investigate crack-vein interactions by simulating cycles of fracturing of a rock mass, sealing the cracks to form veins, and refracturing the rock mass after rotating the stress field. We observe different styles of interaction between new fractures and existing veins, depending on the strength ratio between vein and host rock and on the changes in the stress field between the different deformation stages. If the orientation of stress field does not change between deformation stages, ataxial crack seal veins are produced if the veins are weak and a bundle of subparallel microveins if the veins are strong. If the stress field is rotated between deformation stages, the interactions include reactivation, fracture deflection, and crosscutting. Reactivation of weak veins occurs even if the vein orientation is highly unfavorable relative to the stress field. Relays of fractures between reactivated veins form at a higher angle to the veins than expected. This demonstrates that the orientation of secondary veins does not reflect the regional stress field in a simple manner and that veins can strongly influence fracture connectivity, with implications for paleostress analysis and basin modeling. Simulation results compare well with field examples of multiphase vein networks in carbonates from Jebel Akhdar, Oman.

show abstract

“…A critical difference between the mechanical properties of veins and fractures is that veins have a cohesion and therefore are able to accommodate tensile stress [ Caputo , ]. Depending on the strength ratio between host rock, vein, and interface, the new fracture will localize either in the vein, at the vein‐host rock interface, or in the host rock [ Caputo and Hancock , ; Holland and Urai , ].If the vein is weaker than the host rock and the interface, fracturing localizes in the vein, producing syntaxial or ataxial crack‐seal microstructure. Repeated delamination of the vein‐host rock interfaces creates antitaxial crack‐seal microstructures and inclusion bands for cases where the interface is the weakest element of the system [ Durney and Ramsay , ; Urai and Williams , ; Passchier and Trouw , ; Bons et al ., ].If the vein and the interface are stronger than the host rock, fractures tend to form in the host rock.…”

Section: Introductionmentioning

confidence: 99%

Extension fracture propagation in rocks with veins: Insight into the crack‐seal process using Discrete Element Method modeling

2013

Self Cite

View full text Add to dashboard Cite

[1] We investigate how existing veins interact with extension fractures in rocks using 3-D Discrete Element Method models with a geometry inspired by tension tests with notched samples. In a sensitivity study, we varied (a) the angle between the vein and the bulk extension direction and (b) the strength ratio between host rock and vein material. Results show a range of vein-fracture interactions, which fall into different, robust, "structural styles." Veins, which are weaker than the host rock, tend to localize fracturing into the vein, even at high-misorientation angles. Veins, which are stronger than the host rock, cause deflection of the fracture tip along the vein-host rock interface. Fractures are arrested at the interface from weak to stronger material. When propagating from a stronger to a weaker material, macroscopic bifurcation of the fracture is common. Complex interactions are favored by a low angle between the vein and the fracture and by high-strength contrast. The structural styles in the models show good agreement with microstructures and mesostructures of crack-seal veins found in natural systems. We propose that these structural styles form the basis for criteria to recognize strength contrasts and stress of crack-seal systems in nature.Citation: Virgo, S., S. Abe, and J. L. Urai (2013), Extension fracture propagation in rocks with veins: Insight into the crack-seal process using Discrete Element Method modeling,

show abstract

Evolution of anastomosing crack–seal vein networks in limestones: Insight from an exhumed high-pressure cell, Jabal Shams, Oman Mountains

Cited by 67 publications

References 38 publications

Fault and fracture patterns in low porosity chalk and their potential influence on sub-surface fluid flow—A case study from Flamborough Head, UK

Fault and fracture patterns in low porosity chalk and their potential influence on sub-surface fluid flow—A case study from Flamborough Head, UK

The evolution of crack seal vein and fracture networks in an evolving stress field: Insights from Discrete Element Models of fracture sealing

Extension fracture propagation in rocks with veins: Insight into the crack‐seal process using Discrete Element Method modeling

Contact Info

Product

Resources

About