Fractal nature and scaling of normal faults in the Española Basin, Rio Grande rift, New Mexico: implications for fault growth and brittle strain

K. E. Carter, C Larrabee Winter

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

Quaternary faults in the western Española Basin of the Rio Grande rift show a power-law size (displacement) distribution suggesting that faulting in this region is scale invariant, and that faults are self similar. The power law, or fractal, distribution is characterized by fractal dimension of 0.66 to 0.79 and represents a young, immature, active fault population in a continental extensional regime. Based on this distribution, it is estimated that unobserved faults with very small displacements account for up to 6% of the total strain. Since 1.2 Ma. total extension in this part of the basin has been at least 5%. A direct correlation exists between maximum displacement and length of faults in this area suggesting that they obey a scaling relationship in which the ratio of log dmax/log L is 5 × 10-3. This ratio is nearly constant for faults whose lengths span three-orders of magnitude, indicating that there is no difference in the scaling relationship of displacement and length between faults of all sizes. Considering previous models, these fault characteristics suggest that, in the western Española Basin: (1) host rock shear strengths are low; (2) remote shear stresses were probably high: and (3) most faults do not extend throughout the brittle crust. Finally, displacement profiles on five of the largest faults arc asymmetric and show a rapid decrease in displacement from the point of maximum displacement toward the fault tip. The fractal nature, scaling relationship and distribution of displacement on faults are used to suggest that faults grew by nearly proportional increases in displacement and length, perhaps by mechanisms dominated by propagating shear fractures rather than by linkage of pre-existing joints or faults.

Original languageEnglish (US)
Pages (from-to)863-873
Number of pages11
JournalJournal of Structural Geology
Volume17
Issue number6
DOIs
StatePublished - 1995
Externally publishedYes

Fingerprint

growth fault
normal fault
basin
power law
active fault
shear strength
host rock
shear stress
faulting

ASJC Scopus subject areas

  • Geology

Cite this

@article{b223d9a9682b46459b09a8fb5c2c83c9,
title = "Fractal nature and scaling of normal faults in the Espa{\~n}ola Basin, Rio Grande rift, New Mexico: implications for fault growth and brittle strain",
abstract = "Quaternary faults in the western Espa{\~n}ola Basin of the Rio Grande rift show a power-law size (displacement) distribution suggesting that faulting in this region is scale invariant, and that faults are self similar. The power law, or fractal, distribution is characterized by fractal dimension of 0.66 to 0.79 and represents a young, immature, active fault population in a continental extensional regime. Based on this distribution, it is estimated that unobserved faults with very small displacements account for up to 6{\%} of the total strain. Since 1.2 Ma. total extension in this part of the basin has been at least 5{\%}. A direct correlation exists between maximum displacement and length of faults in this area suggesting that they obey a scaling relationship in which the ratio of log dmax/log L is 5 × 10-3. This ratio is nearly constant for faults whose lengths span three-orders of magnitude, indicating that there is no difference in the scaling relationship of displacement and length between faults of all sizes. Considering previous models, these fault characteristics suggest that, in the western Espa{\~n}ola Basin: (1) host rock shear strengths are low; (2) remote shear stresses were probably high: and (3) most faults do not extend throughout the brittle crust. Finally, displacement profiles on five of the largest faults arc asymmetric and show a rapid decrease in displacement from the point of maximum displacement toward the fault tip. The fractal nature, scaling relationship and distribution of displacement on faults are used to suggest that faults grew by nearly proportional increases in displacement and length, perhaps by mechanisms dominated by propagating shear fractures rather than by linkage of pre-existing joints or faults.",
author = "Carter, {K. E.} and Winter, {C Larrabee}",
year = "1995",
doi = "10.1016/0191-8141(94)00105-9",
language = "English (US)",
volume = "17",
pages = "863--873",
journal = "Journal of Structural Geology",
issn = "0191-8141",
publisher = "Elsevier Limited",
number = "6",

}

TY - JOUR

T1 - Fractal nature and scaling of normal faults in the Española Basin, Rio Grande rift, New Mexico

T2 - implications for fault growth and brittle strain

AU - Carter, K. E.

AU - Winter, C Larrabee

PY - 1995

Y1 - 1995

N2 - Quaternary faults in the western Española Basin of the Rio Grande rift show a power-law size (displacement) distribution suggesting that faulting in this region is scale invariant, and that faults are self similar. The power law, or fractal, distribution is characterized by fractal dimension of 0.66 to 0.79 and represents a young, immature, active fault population in a continental extensional regime. Based on this distribution, it is estimated that unobserved faults with very small displacements account for up to 6% of the total strain. Since 1.2 Ma. total extension in this part of the basin has been at least 5%. A direct correlation exists between maximum displacement and length of faults in this area suggesting that they obey a scaling relationship in which the ratio of log dmax/log L is 5 × 10-3. This ratio is nearly constant for faults whose lengths span three-orders of magnitude, indicating that there is no difference in the scaling relationship of displacement and length between faults of all sizes. Considering previous models, these fault characteristics suggest that, in the western Española Basin: (1) host rock shear strengths are low; (2) remote shear stresses were probably high: and (3) most faults do not extend throughout the brittle crust. Finally, displacement profiles on five of the largest faults arc asymmetric and show a rapid decrease in displacement from the point of maximum displacement toward the fault tip. The fractal nature, scaling relationship and distribution of displacement on faults are used to suggest that faults grew by nearly proportional increases in displacement and length, perhaps by mechanisms dominated by propagating shear fractures rather than by linkage of pre-existing joints or faults.

AB - Quaternary faults in the western Española Basin of the Rio Grande rift show a power-law size (displacement) distribution suggesting that faulting in this region is scale invariant, and that faults are self similar. The power law, or fractal, distribution is characterized by fractal dimension of 0.66 to 0.79 and represents a young, immature, active fault population in a continental extensional regime. Based on this distribution, it is estimated that unobserved faults with very small displacements account for up to 6% of the total strain. Since 1.2 Ma. total extension in this part of the basin has been at least 5%. A direct correlation exists between maximum displacement and length of faults in this area suggesting that they obey a scaling relationship in which the ratio of log dmax/log L is 5 × 10-3. This ratio is nearly constant for faults whose lengths span three-orders of magnitude, indicating that there is no difference in the scaling relationship of displacement and length between faults of all sizes. Considering previous models, these fault characteristics suggest that, in the western Española Basin: (1) host rock shear strengths are low; (2) remote shear stresses were probably high: and (3) most faults do not extend throughout the brittle crust. Finally, displacement profiles on five of the largest faults arc asymmetric and show a rapid decrease in displacement from the point of maximum displacement toward the fault tip. The fractal nature, scaling relationship and distribution of displacement on faults are used to suggest that faults grew by nearly proportional increases in displacement and length, perhaps by mechanisms dominated by propagating shear fractures rather than by linkage of pre-existing joints or faults.

UR - http://www.scopus.com/inward/record.url?scp=0029504516&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0029504516&partnerID=8YFLogxK

U2 - 10.1016/0191-8141(94)00105-9

DO - 10.1016/0191-8141(94)00105-9

M3 - Article

AN - SCOPUS:0029504516

VL - 17

SP - 863

EP - 873

JO - Journal of Structural Geology

JF - Journal of Structural Geology

SN - 0191-8141

IS - 6

ER -