Changes

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{| class = "wikitable"

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! Variable

! Variable || Control on ductility

! Control on ductility

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| Lithology

| Lithology || Grain mineralogy and cement type control ductility. Brittle seals include dolostone, quartzite, anhydrite, and some shales. Ductile seals include halite, some shales, and some limestones.

| Grain mineralogy and cement type control ductility. Brittle seals include dolostone, quartzite, anhydrite, and some shales. Ductile seals include halite, some shales, and some limestones.

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| Composition

| Composition || Not all limestones or shales have the same ductility. Compositional variations such as total organic carbon<ref name=ch10r13>Chong, K., P., Hoyt, P., M., Smith, J., W., Paulsen, B., Y., 1980, Effects of strain rate on oil shale fracturing: International Journal of Rock Mechanics, vol. 17, no. 1, p. 35–43., 10., 1016/0148-9062(80)90004-2</ref> and clay mineralogy<ref name=ch10r14>Corbett, K., Friedman, M., Spang, J., 1987, [http://archives.datapages.com/data/bulletns/1986-87/data/pg/0071/0001/0000/0017.htm Fracture development and mechanical stratigraphy of Austin Chalk, Texas]: AAPG Bulletin, vol. 71, no. 1, p. 17–28.</ref> change ductility.

| Not all limestones or shales have the same ductility. Compositional variations such as total organic carbon<ref name=ch10r13>Chong, K., P., Hoyt, P., M., Smith, J., W., Paulsen, B., Y., 1980, Effects of strain rate on oil shale fracturing: International Journal of Rock Mechanics, vol. 17, no. 1, p. 35–43., 10., 1016/0148-9062(80)90004-2</ref> and clay mineralogy<ref name=ch10r14>Corbett, K., Friedman, M., Spang, J., 1987, [http://archives.datapages.com/data/bulletns/1986-87/data/pg/0071/0001/0000/0017.htm Fracture development and mechanical stratigraphy of Austin Chalk, Texas]: AAPG Bulletin, vol. 71, no. 1, p. 17–28.</ref> change ductility.

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| Confining pressure

| Confining pressure || Increasing confining pressure increases ductility.

| Increasing confining pressure increases ductility.

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| Pore pressure

| Pore pressure || Increasing pore pressure decreases ductility.

| Increasing pore pressure decreases ductility.

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| Fluid composition

| Fluid composition || The presence or absence of fluids and their composition affects ductility.

| The presence or absence of fluids and their composition affects ductility.

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| Temperature

| Temperature || Increasing temperature increases ductility.

| Increasing temperature increases ductility.

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| Strain rate

| Strain rate || High strain rates decrease ductility.

| High strain rates decrease ductility.

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| Time

| Time || Ductility changes with time as seals undergo burial and diagenesis.

| Ductility changes with time as seals undergo burial and diagenesis.

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| Compaction state

| Compaction state || Ductility decreases with progressive compaction and diagenesis.

| Ductility decreases with progressive compaction and diagenesis.

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