A Comparative Review of Mechanical and Petrographic Properties and Their Role in Estimating the Brittleness Index of Norite: Implications for Geomechanical Applications
Source abstract
Abstract
Norite is a coarse-grained mafic igneous rock dominated by essential calcic plagioclase and orthopyroxene. Norite is known for its toughness, and it has a high compressive strength which makes it important in engineering. This paper examines the mechanical and petrographic properties of norite, including their relevance to geomechanical applications. Despite improvements in brittleness estimation, standardizing brittleness indices remains a challenge due to geological variability, incompatible petrographic techniques, and difficulties in relating mineral composition to mechanical behavior. Current brittleness models mainly rely on mechanical properties, often ignoring key petrographic factors like grain size, mineral composition, alteration, and porosity. This limits their accuracy, especially for complex rocks like norite. Few studies integrate both petrographic and mechanical data, creating a gap in fully understanding the geomechanical behavior of norite. This review was carried out by examining the origin, formation, and petrographic properties of norite, and a comparative analysis of its strength, flexibility, mineral structure, and fracture mechanics was conducted, highlighting their importance in the engineering and mining industries. The results of this study highlight how factors like strength, brittleness, and durability influence norite’s suitability for geomechanical applications in mining, tunneling, and construction. Furthermore, the results outline that the mineral composition of norite affects its strength, with quartz enhancing strength and altered minerals like feldspar, mica, and biotite weakening the rock and making it more prone to fracturing. These results are important for tunneling projects as they help predict how rocks will behave, ensuring tunnel stability and better design in underground support systems.
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Research context
OpenAlex topics: Rock Mechanics and Modeling · Tunneling and Rock Mechanics · Drilling and Well Engineering
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Mining, Minerals and Geomatics Engineering, University of South Africa, Florida Campus, Private Bag X6, Johannesburg 1710, South Africa
Department of Geology and Mining, University of Limpopo, Private Bag X1106, Sovenga 0727, South Africa
Funding
Mining Qualification Authority (MQA) · University of South Africa postgraduate support bursary · University of South Africa
References (100+)
Show source-provided references
1. Rock-Strength and Physical Properties of Norites of the Merensky and Bastard Units, Western Bushveld Complex10.2113/108.4.525 ↗
2. On the Experimental Determination of Poisson’s Ratio for Intact Rocks and Its Variation as Deformation Develops10.1155/2021/8843056 ↗
3. Waterton, P., Hyde, W.R., Tusch, J., Hollis, J.A., Kirkland, C.L., Kinney, C., Yakymchuk, C., Gardiner, N.J., Zakharov, D., and Olierook, H.K.H. (2020). Geodynamic Implications of Synchronous Norite and TTG Formation in the 3 Ga Maniitsoq Norite Belt, West Greenland. Front. Earth Sci., 8.10.3389/feart.2020.562062 ↗
4. Hunt, E.J., Latypov, R., and Horváth, P. (2018). The Merensky Cyclic Unit, Bushveld Complex, South Africa: Reality or Myth?. Minerals, 8.10.3390/min8040144 ↗
5. Long-Term Durability of Rock-Based Geopolymers Aged at Downhole Conditions for Oil Well Cementing Operations
6. The Evaluation of Rock Brittleness and Its Application: A Review Study10.1080/19648189.2019.1655485 ↗
7. A Review of Relationship between Texture Characteristic and Mechanical Properties of Rock10.3390/geotechnics2010012 ↗
8. Evaluation of Methods for Determining Rock Brittleness under Compression10.1016/j.jngse.2020.103321 ↗
9. Li, D., Han, M., and Zhu, Q. (2023). Evaluation of Rock Brittleness Index under Dynamic Load. Appl. Sci., 13.10.3390/app13084698 ↗
10. Gardner, L.J., and Bosman, J.D. (2015, January 10–13). Determining the Mechanical Properties of Igneous Rocks in the Western Limb of South Africa’s Bushveld Complex. Proceedings of the Paper Presented at the 13th ISRM International Congress of Rock Mechanics, Montreal, QC, Canada. One Petrography.
11. Origin and Significance of Noritic Blocks in Layered Anorthosites in the Bushveld Complex, South Africa10.1007/s00410-021-01872-8 ↗
12. Geoheritage of the Eastern Limb of the Bushveld Igneous Complex, South Africa: A Uniquely Exposed Layered Igneous Intrusion10.1007/s12371-019-00360-7 ↗
13. Norite and Charnockites from the Venda Nova Pluton, SE Brazil: Intensive Parameters and Some Petrogenetic Constraints10.1016/j.gsf.2012.05.009 ↗
14. The Earliest Stages of Emplacement of the Eastern Bushveld Complex: Development of the Lower Zone, Marginal Zone and Basal Ultramafic Sequence10.1093/petrology/egv003 ↗
15. Harger, H.G.S. (2025, April 24). The Geological Society of South Africa; 1934; Volume 37. Available online: https://journals.co.za/doi/pdf/10.10520/AJA10120750_1669.
16. Cawthorn, R.G. (2015). The Bushveld Complex, South Africa. Springer Geology, Springer.10.1007/978-94-017-9652-1_12 ↗
17. Connectivity between the Western and Eastern Limbs of the Bushveld Complex10.1016/S0040-1951(00)00227-4 ↗
18. A Quartz-Bearing Norite Formed by the Bowen Reaction at a Dioritepelite Contact10.1130/G39264.1 ↗
19. Origin of the UG2 Chromitite Layer, Bushveld Complex10.1093/petrology/egl069 ↗
20. The Bushveld Complex
21. Igneous Rock Associations 23. The Bushveld Complex, South Africa: New Insights and Paradigms10.12789/geocanj.2018.45.138 ↗
22. The Reaction Principle In Petrogenesis
23. Bowen, N.L. (1928). The Evolution of the Igneous Rocks, Dover Publications.
24. Trace Elements in the Merensky Reef and Adjacent Norites Bushveld Complex South Africa10.1007/s00126-005-0030-x ↗
25. The Pan-African Kekem Gabbro-Norite (West-Cameroon), U-Pb Zircon Age, Geochemistry and Sr-Nd Isotopes: Geodynamical Implication for the Evolution of the Central African Fold Belt10.1016/j.jafrearsci.2013.03.010 ↗
26. Petrology of the Noritic and Gabbronoritic Rocks below the J-M Reef in the Mountain View Area, Stillwater Complex, Montana
27. Estimation of Brittleness Indexes from Petrographic Characteristics of Different Sandstone Types (Cenozoic and Mesozoic Sandstones), Markazi Province, Iran10.1007/s00603-021-02441-y ↗
28. Predicting the Brittleness of Granitic Rocks in Tavandasht and Gosheh (Borujerd) by Schmidt Hardness and Petrographic Characteristics
29. Schulz, B., Sandmann, D., and Gilbricht, S. (2020). Sem-Based Automated Mineralogy and Its Application in Geo-and Material Sciences. Minerals, 10.10.3390/min10111004 ↗
30. Ryoke Zone Of The Toyone-Mura Area, Aichi Prefecture, Japan10.2465/ganko1941.69.52 ↗
31. Evaluation of Rock Burstability with Mechanical Property Testing and Microscopic Image Analysis10.1007/s00603-024-03797-7 ↗
32. Effects of Grain Size on the Initiation and Propagation Thresholds of Stress-Induced Brittle Fractures10.1007/s006030050026 ↗
33. Brittleness Index of High-Rank Coal Reservoir and Its Influencing Factors in Mabidong Block, Qinshui Basin, China
34. Correlation between Mineralogical Characteristics and Engineering Properties of Granitic Rocks
35. Göğüş, Ö.D., Avşar, E., Develi, K., and Çalık, A. (2024). The Role of Mineralogical and Textural Complexity in the Damage Evolution of Brittle Rocks. Sci. Rep., 14.10.1038/s41598-024-79940-9 ↗
36. A Grain Texture Model to Investigate Effects of Grain Shape and Orientation on Macro-Mechanical Behavior of Crystalline Rock10.1016/j.ijrmms.2021.104971 ↗
37. Influence of Grain Size Heterogeneity on Strength and Microcracking Behavior of Crystalline Rocks10.1002/2016JB013469 ↗
38. Estimating the Strength of Rock Materials
39. Long-Term Performance of Activated Carbon Air Cathodes with Different Diffusion Layer Porosities in Microbial Fuel Cells10.1016/j.bios.2011.08.025 ↗
40. Evidence for Polybaric Fractional Crystallization in a Continental Arc: Hidden Lakes Mafic Complex, Sierra Nevada Batholith, California10.1007/s00410-021-01844-y ↗
41. Trouw, R.A.J., and Passchier, C.W. (2005). Microtectonics, Springer.
42. Prediction of Mechanical Properties of Igneous Rocks Under Combined Compression and Shear Loading Through Statistical Analysis10.1007/s00603-019-01948-9 ↗
43. Correlation of TBM and Drilling Machine Performances with Rock Brittleness10.1016/S0013-7952(02)00192-8 ↗
44. Determination of the Uniaxial Compressive Strength of Rocks from the Strength Index10.35180/gse-2022-0078 ↗
45. Jaeger, J.C., and Cooke, N.G.W. (1877). Fundamentals of Rock Mechanics, Chapman Hall.
46. Fairhurst, C., and Cooke, N.G.W. (October, January 25). The Phenomenon of Rock Splitting Parallel to a Free Surface under Compressive Stress. Proceedings of the First Congress of the International Society of Rock Mechanics, Lisbon, Portugal.
47. Tensile Fracture Strength of Brisbane Tuff by Static and Cyclic Loading Tests10.1007/s00603-013-0469-5 ↗
48. A Review of the Tensile Strength of Rock: Concepts and Testing10.1007/s10706-014-9732-0 ↗
49. Fracture of Anisotropic Rock
50. Dependence of Fracture Strength of Rocks on Grain Size. Bulletin of Mineral Industries Experiment Station, Mining Engineering Series. Rock Mechanics
51. Ulusay, R., and Hudson, J.A. (2007). The Complete ISRM Suggested Methods for Rock Characterization, Testing and Monitoring: 1974–2006, The ISRM Turkish National Group. Commission on Testing Methods, International Society of Rock Mechanics.
52. Technical Note: Determination Of Young’s Modulus And Poisson’s Ratio For Intact Stratified Rocks and Their Relationship with Uniaxial Compressive Strength
53. The Role of Fractures, Effective Pressure and Loading on the Difference between the Static and Dynamic Poisson’s Ratio and Young’s Modulus of Westerly Granite10.1016/j.ijrmms.2019.03.001 ↗
54. Poisson’s Ratio Values for Rocks10.1016/j.ijrmms.2006.04.011 ↗
55. Estimation of Rock Modulus: For Intact Rocks with an Artificial Neural Network and for Rock Masses with a New Empirical Equation10.1016/j.ijrmms.2005.06.007 ↗
56. Modified Hoek-Brown Failure Criterion for Anisotropic Rock Mass
57. The Stress-Strain Behaviour of Rock Material Related to Fracture under Compression10.1016/S0013-7952(97)00061-6 ↗
58. Roylance, D. (2001). Introduction to Fracture Mechanics, NBS Special Publication.
59. Generalized Crack Initiation and Crack Damage Stress Thresholds of Brittle Rock Masses near Underground Excavations10.1016/j.ijrmms.2004.02.001 ↗
60. Effects of Ground Fracturing with Horizontal Fracture Plane on Rock Breakage Characteristics and Mine Pressure Control10.1007/s00603-020-02294-x ↗
61. Quantitative Seismic Interpretation of Rock Brittleness Based on Statistical Rock Physics10.1190/geo2018-0094.1 ↗
62. Testing and Modeling of the Mechanical Behavior of Dolomite in the Wudongde Hydropower Plant10.1080/17486025.2016.1151557 ↗
63. A Brittleness Index to Estimate Fracture Toughness10.1016/j.ijrmms.2003.07.010 ↗
64. The Evaluation of Rock Brittleness Concept on Rotary Blast Hole Drills
65. Assessment of Brittleness Using Rock Strength and Density with Punch Penetration Test10.1016/j.tust.2008.04.002 ↗
66. Rock Brittleness Indices and Their Applications to Different Fields of Rock Engineering: A Review10.1016/j.jrmge.2020.06.008 ↗
67. A New Method to Evaluate Rock Mass Brittleness Based on Stress–Strain Curves of Class I10.1007/s00603-017-1174-6 ↗
68. Shale Brittleness Evaluation Based on Energy Balance Analysis of Stress-Strain Curves10.1016/j.petrol.2018.03.061 ↗
69. Quantitative Evaluation of Rock Brittleness Based on Crack Initiation Stress and Complete Stress–Strain Curves10.1007/s10064-019-01486-2 ↗
70. Influence of Mineral Composition on Rock Mechanics Properties and Brittleness Evaluation of Surrounding Rocks in Soft Coal Seams10.1021/acsomega.3c07731 ↗
71. Corkum, A.G., Lorig, L.J., and DeGagne, D.O. (2012, January 24–27). Continuum Representation of Brittle Rock Failure Bulking-Induced Displacements around Tunnels. Proceedings of the 46th US Rock Mechanics/Geomechanics Symposium, Chicago, IL, USA.
72. Brittleness and the Mechanical Winning of Coal10.1016/S0167-9031(86)90305-1 ↗
73. Brittleness and Micro-Scale Rock Cutting Efficiency10.1016/0167-9031(91)90339-E ↗
74. Influence of Rock Brittleness on TBM Penetration Rate in Singapore Granite10.1016/j.tust.2006.07.004 ↗
75. Prediction of TBM Penetration Rate Using Intact and Mass Rock Properties (Case Study: Zagros Long Tunnel, Iran)10.1007/s12517-014-1465-0 ↗
76. Hucka, V., and Das, B. (1974). Brittleness Determination of Rocks by Different Methods. Pergamon Press.10.1016/0148-9062(74)91109-7 ↗
77. Jin, X.C., Shah, S.N., Truax, J.A., and Roegiers, J. (2014, January 27–29). A Practical Petrophysical Approach for Brittleness Prediction from Porosity and Sonic Logging in Shale Reservoirs. Proceedings of the SPE Annual Technical Conference and Exhibition, Amsterdam, The Netherlands.10.2118/170972-MS ↗
78. Comprehensive Prediction of Rockburst Based on Analysis of Strain Energy in Rocks10.1016/S0886-7798(01)00030-X ↗
79. Rockburst and Its Criteria and Control
80. Knowledge-Based and Data-Driven Fuzzy Modeling for Rockburst Prediction10.1016/j.ijrmms.2013.02.010 ↗
81. Prediction and Prevention of Rockburst in Metal Mines—A Case Study of Sanshandao Gold Mine10.1016/j.jrmge.2015.11.002 ↗
82. Research on Relationship between Crack Initiation Stress Level and Brittleness Indices for Brittle Rocks
83. Bishop, A.W. (1967, January 19–22). Progressive Failure with Special Reference to the Mechanism Causing It. Proceedings of the Geotechnical Conference, Oslo, Norway.
84. Coates, D.F., and Parsons, R.C. (1966). Experimental Criteria for Classification of Rock Substances, Pergamon Press Ltd.10.4095/300105 ↗
85. Brittleness of Rock and Stability Assessment in Hard Rock Tunneling10.1016/S0886-7798(02)00100-1 ↗
86. Baron, L.I., Loguntsov, B.M., and Loguntsov, B.M. (1962). Determination of Properties of Rocks. Gozgotekhizdat Mosc., 231–233.
87. Absolute, Relative and Intrinsic Rock Brittleness at Compression
88. Universal criteria for rock brittleness estimation under triaxial compression10.1016/j.ijrmms.2012.12.011 ↗
89. Evaluation Methodology of Brittleness of Rock Based on Post-Peak Stress–Strain Curves10.1007/s00603-014-0694-6 ↗
90. Indoor Evaluation Method for Shale Brittleness and Improvement
91. Assessment of Some Brittleness Indexes in Rock-Drilling Efficiency10.1007/s00603-009-0057-x ↗
92. Tarokh, A., Peng, J., Fakhimi, A., and Labuz, J.F. (2016, January 26–29). Evaluation of Brittleness from Spalling and Bending Test. Proceedings of the 50th US Rock Mechanics/Geomechanics Symposium, Houston, TX, USA.
93. What Controls the Mechanical Properties of Shale Rocks?—Part II: Brittleness10.1016/j.petrol.2016.02.022 ↗
94. Unconventional Shale-Gas Systems: The Mississippian Barnett Shale of North-Central Texas as One Model for Thermogenic Shale-Gas Assessment
95. Assessment of Mudrock Brittleness with Micro-Scratch Testing10.1007/s00603-017-1279-y ↗
96. Mechanical Properties of Rock Materials with Related to Mineralogical Characteristics and Grain Size through Experimental Investigation: A Comprehensive Review10.1007/s11709-017-0387-9 ↗
97. Mechanical Characteristics and Factors Controlling Brittleness of Organic-Rich Continental Shales10.1016/j.petrol.2020.107464 ↗
98. Textural Characterisation of Rocks10.1016/0013-7952(95)00005-Z ↗
99. Correlation of Mineralogical and Textural Characteristics with Engineering Properties of Granitic Rock from Hulu Langat, Selangor10.1016/j.proche.2016.03.144 ↗
100. Correlation of Mineralogical and Textural Characteristics with Engineering Properties of Selected Granitic Rocks from Turkey10.1016/S0013-7952(98)00071-4 ↗