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Ernesto O. Cristallini - One of the best experts on this subject based on the ideXlab platform.
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Contemporary stress orientations from Borehole Breakout analysis in the southernmost flat‐slab boundary Andean retroarc (32°44′ and 33°40′S)
Journal of Geophysical Research, 2009Co-Authors: Cecilia Griselda Guzman, Ernesto O. CristalliniAbstract:[1] Horizontal stress directions have been determined in the southernmost flat-slab boundary Andean retroarc between 32°44' and 33°40'S within Cuyo Basin, Argentina. These directions were obtained from the Borehole Breakout analysis of 42 wells using four-arm caliper data. The mean maximum horizontal stress (SHmax) direction for the whole region is 104.1° with a 95% confidence interval of 8.1°. The present-day stress field has an approximately preferred E-W trend maximum horizontal stress direction, consistent with the plate boundary forces (80°) and the topographic forces (near E-W). The calculated SHmax directions are near the expected values, but some local deviations were observed. The SHmax rotates from an E-W orientation in the south to a NW-SE orientation to the north of this sector of the Andean retroarc. A regional variation in the stress field can be observed when these results for the Cuyo Basin are analyzed together with those presented in a previous study in the Neuquen Basin to the south. The maximum horizontal stress varies from ∼NW-NE along this combined section of the Andean retroarc, with the ∼E-W SHmax directions in the northern Neuquen Basin consistent with those observed in the southern sector of Cuyo Basin. These variations in the stress field orientation appear related with the topography geometry. From the analysis between the mean SHmax obtained and the acting forces, it can be concluded that the topographic control on the horizontal stress field seems to be dominant in the Cuyo Basin and in the north of Neuquen Basin. To the south of Neuquen Basin the horizontal stress field should be mainly controlled by the plate boundary forces.
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contemporary stress orientations from Borehole Breakout analysis in the southernmost flat slab boundary andean retroarc 32 44 and 33 40 s
Journal of Geophysical Research, 2009Co-Authors: Cecilia Griselda Guzman, Ernesto O. CristalliniAbstract:[1] Horizontal stress directions have been determined in the southernmost flat-slab boundary Andean retroarc between 32°44' and 33°40'S within Cuyo Basin, Argentina. These directions were obtained from the Borehole Breakout analysis of 42 wells using four-arm caliper data. The mean maximum horizontal stress (SHmax) direction for the whole region is 104.1° with a 95% confidence interval of 8.1°. The present-day stress field has an approximately preferred E-W trend maximum horizontal stress direction, consistent with the plate boundary forces (80°) and the topographic forces (near E-W). The calculated SHmax directions are near the expected values, but some local deviations were observed. The SHmax rotates from an E-W orientation in the south to a NW-SE orientation to the north of this sector of the Andean retroarc. A regional variation in the stress field can be observed when these results for the Cuyo Basin are analyzed together with those presented in a previous study in the Neuquen Basin to the south. The maximum horizontal stress varies from ∼NW-NE along this combined section of the Andean retroarc, with the ∼E-W SHmax directions in the northern Neuquen Basin consistent with those observed in the southern sector of Cuyo Basin. These variations in the stress field orientation appear related with the topography geometry. From the analysis between the mean SHmax obtained and the acting forces, it can be concluded that the topographic control on the horizontal stress field seems to be dominant in the Cuyo Basin and in the north of Neuquen Basin. To the south of Neuquen Basin the horizontal stress field should be mainly controlled by the plate boundary forces.
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Contemporary stress orientations in the Andean retroarc between 34°S and 39°S from Borehole Breakout analysis
Tectonics, 2007Co-Authors: Cecilia Griselda Guzman, Ernesto O. Cristallini, Germán BottesiAbstract:[1] In this paper we present the results of the analysis of Borehole Breakouts from 115 wells drilled within Neuquen Basin in the Andean retroarc between 34° and 39°S (Argentina). The first-order present-day stress orientation in the Andean retroarc is expected to be mainly controlled by the plate boundary forces (azimuth 80°) and the topographic forces (E–W). The obtained maximum horizontal stress (SHmax) has a preferred trend with a resultant direction of azimuth 88.7° and a 95% confidence interval of 13.3° consistent with the expected trend. The horizontal stress trajectory map achieved for this region shows that the SHmax along the study area is not completely uniform. To the north of Colorado River, the SHmax shows an ESE tendency interpreted as significant influenced by the topographic forces. To the south of Colorado River, SHmax has an ENE trend similar to the expected based on plate boundary forces. To the southeast of the region, a NE direction was found, probably showing a basement structural control in the stress field geometry. The stress orientations obtained for the whole region show that plate boundary forces, drag basal, and topographic forces are strongly controlling the stress direction distribution.
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contemporary stress orientations in the andean retroarc between 34 s and 39 s from Borehole Breakout analysis
Tectonics, 2007Co-Authors: Cecilia Griselda Guzman, Ernesto O. Cristallini, Germán BottesiAbstract:[1] In this paper we present the results of the analysis of Borehole Breakouts from 115 wells drilled within Neuquen Basin in the Andean retroarc between 34° and 39°S (Argentina). The first-order present-day stress orientation in the Andean retroarc is expected to be mainly controlled by the plate boundary forces (azimuth 80°) and the topographic forces (E–W). The obtained maximum horizontal stress (SHmax) has a preferred trend with a resultant direction of azimuth 88.7° and a 95% confidence interval of 13.3° consistent with the expected trend. The horizontal stress trajectory map achieved for this region shows that the SHmax along the study area is not completely uniform. To the north of Colorado River, the SHmax shows an ESE tendency interpreted as significant influenced by the topographic forces. To the south of Colorado River, SHmax has an ENE trend similar to the expected based on plate boundary forces. To the southeast of the region, a NE direction was found, probably showing a basement structural control in the stress field geometry. The stress orientations obtained for the whole region show that plate boundary forces, drag basal, and topographic forces are strongly controlling the stress direction distribution.
Cecilia Griselda Guzman - One of the best experts on this subject based on the ideXlab platform.
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Contemporary stress orientations from Borehole Breakout analysis in the southernmost flat‐slab boundary Andean retroarc (32°44′ and 33°40′S)
Journal of Geophysical Research, 2009Co-Authors: Cecilia Griselda Guzman, Ernesto O. CristalliniAbstract:[1] Horizontal stress directions have been determined in the southernmost flat-slab boundary Andean retroarc between 32°44' and 33°40'S within Cuyo Basin, Argentina. These directions were obtained from the Borehole Breakout analysis of 42 wells using four-arm caliper data. The mean maximum horizontal stress (SHmax) direction for the whole region is 104.1° with a 95% confidence interval of 8.1°. The present-day stress field has an approximately preferred E-W trend maximum horizontal stress direction, consistent with the plate boundary forces (80°) and the topographic forces (near E-W). The calculated SHmax directions are near the expected values, but some local deviations were observed. The SHmax rotates from an E-W orientation in the south to a NW-SE orientation to the north of this sector of the Andean retroarc. A regional variation in the stress field can be observed when these results for the Cuyo Basin are analyzed together with those presented in a previous study in the Neuquen Basin to the south. The maximum horizontal stress varies from ∼NW-NE along this combined section of the Andean retroarc, with the ∼E-W SHmax directions in the northern Neuquen Basin consistent with those observed in the southern sector of Cuyo Basin. These variations in the stress field orientation appear related with the topography geometry. From the analysis between the mean SHmax obtained and the acting forces, it can be concluded that the topographic control on the horizontal stress field seems to be dominant in the Cuyo Basin and in the north of Neuquen Basin. To the south of Neuquen Basin the horizontal stress field should be mainly controlled by the plate boundary forces.
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contemporary stress orientations from Borehole Breakout analysis in the southernmost flat slab boundary andean retroarc 32 44 and 33 40 s
Journal of Geophysical Research, 2009Co-Authors: Cecilia Griselda Guzman, Ernesto O. CristalliniAbstract:[1] Horizontal stress directions have been determined in the southernmost flat-slab boundary Andean retroarc between 32°44' and 33°40'S within Cuyo Basin, Argentina. These directions were obtained from the Borehole Breakout analysis of 42 wells using four-arm caliper data. The mean maximum horizontal stress (SHmax) direction for the whole region is 104.1° with a 95% confidence interval of 8.1°. The present-day stress field has an approximately preferred E-W trend maximum horizontal stress direction, consistent with the plate boundary forces (80°) and the topographic forces (near E-W). The calculated SHmax directions are near the expected values, but some local deviations were observed. The SHmax rotates from an E-W orientation in the south to a NW-SE orientation to the north of this sector of the Andean retroarc. A regional variation in the stress field can be observed when these results for the Cuyo Basin are analyzed together with those presented in a previous study in the Neuquen Basin to the south. The maximum horizontal stress varies from ∼NW-NE along this combined section of the Andean retroarc, with the ∼E-W SHmax directions in the northern Neuquen Basin consistent with those observed in the southern sector of Cuyo Basin. These variations in the stress field orientation appear related with the topography geometry. From the analysis between the mean SHmax obtained and the acting forces, it can be concluded that the topographic control on the horizontal stress field seems to be dominant in the Cuyo Basin and in the north of Neuquen Basin. To the south of Neuquen Basin the horizontal stress field should be mainly controlled by the plate boundary forces.
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Contemporary stress orientations in the Andean retroarc between 34°S and 39°S from Borehole Breakout analysis
Tectonics, 2007Co-Authors: Cecilia Griselda Guzman, Ernesto O. Cristallini, Germán BottesiAbstract:[1] In this paper we present the results of the analysis of Borehole Breakouts from 115 wells drilled within Neuquen Basin in the Andean retroarc between 34° and 39°S (Argentina). The first-order present-day stress orientation in the Andean retroarc is expected to be mainly controlled by the plate boundary forces (azimuth 80°) and the topographic forces (E–W). The obtained maximum horizontal stress (SHmax) has a preferred trend with a resultant direction of azimuth 88.7° and a 95% confidence interval of 13.3° consistent with the expected trend. The horizontal stress trajectory map achieved for this region shows that the SHmax along the study area is not completely uniform. To the north of Colorado River, the SHmax shows an ESE tendency interpreted as significant influenced by the topographic forces. To the south of Colorado River, SHmax has an ENE trend similar to the expected based on plate boundary forces. To the southeast of the region, a NE direction was found, probably showing a basement structural control in the stress field geometry. The stress orientations obtained for the whole region show that plate boundary forces, drag basal, and topographic forces are strongly controlling the stress direction distribution.
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contemporary stress orientations in the andean retroarc between 34 s and 39 s from Borehole Breakout analysis
Tectonics, 2007Co-Authors: Cecilia Griselda Guzman, Ernesto O. Cristallini, Germán BottesiAbstract:[1] In this paper we present the results of the analysis of Borehole Breakouts from 115 wells drilled within Neuquen Basin in the Andean retroarc between 34° and 39°S (Argentina). The first-order present-day stress orientation in the Andean retroarc is expected to be mainly controlled by the plate boundary forces (azimuth 80°) and the topographic forces (E–W). The obtained maximum horizontal stress (SHmax) has a preferred trend with a resultant direction of azimuth 88.7° and a 95% confidence interval of 13.3° consistent with the expected trend. The horizontal stress trajectory map achieved for this region shows that the SHmax along the study area is not completely uniform. To the north of Colorado River, the SHmax shows an ESE tendency interpreted as significant influenced by the topographic forces. To the south of Colorado River, SHmax has an ENE trend similar to the expected based on plate boundary forces. To the southeast of the region, a NE direction was found, probably showing a basement structural control in the stress field geometry. The stress orientations obtained for the whole region show that plate boundary forces, drag basal, and topographic forces are strongly controlling the stress direction distribution.
Birgit Müller - One of the best experts on this subject based on the ideXlab platform.
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impact of fracture networks on Borehole Breakout heterogeneities in crystalline rock
International Journal of Rock Mechanics and Mining Sciences, 2014Co-Authors: David P. Sahara, Martin Schoenball, Thomas Kohl, Birgit MüllerAbstract:This study describes a systematic analysis of Breakout occurrence, variation of Breakout orientation and fracture characteristics. We infer the impact of fracture networks on the development of Breakouts from detailed analysis of 1221 Borehole elongation pairs in the vicinity of 1871 natural fractures observed in the crystalline section of the GPK4 well of the Soultz-sous-Forets geothermal field (France). Breakout orientation anomalies are found to concentrate in the immediate vicinity of fault cores and to decrease with distance to the fault core. Patterns of Breakout orientation in the vicinity of natural fractures suggest that the Breakout rotation, relative to the mean Shmin direction, is strongly influenced by the fracture orientation. Even a direct relationship between fracture and Breakout orientations is found in some depth intervals. In highly fractured zones, with different fracture families present, Breakout orientations are especially heterogeneous, resulting from the overlapping effects of the fracture network. Additionally, Breakouts are typically found to be asymmetrical in zones with high fracture density. Borehole Breakout heterogeneities do not seem to be related to the principal stress heterogeneity only, but also to the effect of mechanical heterogeneities like weak zones with different elastic moduli, rock strength and fracture patterns. Consequently, care has to be taken when inferring the principal stress orientation from Borehole Breakout data observed in fractured rock.
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The tectonic regime in Italy inferred from Borehole Breakout data
Tectonophysics, 2002Co-Authors: Maria Teresa Mariucci, Birgit MüllerAbstract:Abstract In Italy, the horizontal stress directions are well constrained in many regions, but the tectonic regime is not well known because the stress magnitudes are unknown. Our intention is to improve the knowledge of crustal stress in Italy, both at shallow depth and in low seismicity areas. Therefore, we inferred the tectonic regime from the comparison between the depth of Breakout occurrence and the physical properties of the rocks in 20 Boreholes. The critical value of the maximum horizontal stress, for which the effective tangential stress at the Borehole wall overcomes the rock strength to form Breakouts, could be computed from rock strength and density. Comparing the theoretical stress distributions for different tectonic regimes with the depth distribution of Breakout occurrence, it is possible to infer the tectonic regime that fits best to the Breakout depth distribution. We investigated Boreholes up to 6 km deep located in different tectonic environments over the Italian peninsula: the Po Plain, the Apenninic chain, the Adriatic foredeep and the Tyrrhenian Quaternary volcanic region. These wells are characterised by Breakout data of good quality (A, B and C, according to World Stress Map quality ranking system). The results are in general agreement with the style of faulting derived from earthquake focal mechanisms and other stress indicators. Our results show a predominance of a normal faulting (NF) regime in the inner Apennines and both normal faulting and strike–slip faulting (SS) style in the surrounding regions, possibly also associated with changes in the tectonic regime with depth.
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Patterns of tectonic stress in Sicily from Borehole Breakout observations and finite element modeling
Tectonics, 1999Co-Authors: Steffen Ragg, Mario Grasso, Birgit MüllerAbstract:The orientation of in situ tectonic stress was deduced from Borehole Breakout analysis of 22 wells from onshore Sicily. The results allow us to distinguish the stress field of different geological units: (1) A nearly NNW (148°) orientation is detected in the Hyblean Plateau. (2) A NNE SHmax direction characterizes the Gela area. To the north, within the thrust belt (around Mount Judica), the SHmax direction swings to NE. In the northeastern segment of the foredeep, the Catania Plain, the direction of SHmax is roughly parallel to the NE trending grabens that mark the northern margin of the Hyblean Plateau. (3) The southwestern segment of the foredeep has no preferential SHmax orientation and may act as a transition zone with isotropic horizontal stresses. (4) In western Sicily a SHmax orientation from N–S to NW–SE is observed. This fits well the kinematics of the SE migrating Egadi and Adventure thrust belts and the direction of shortening inferred from the modern seismicity of the area. A three-dimensional finite element modeling, including the most important tectonic features, was performed. Modeling results of the stress field indicate that the NNW trending SHmax is locally influenced by the variation of crustal thickness and local zones of weakness. In addition, the Pantelleria Rift causes a rotation of the regional NW–SE stress orientation to NNE along the northern rim of the rift system, including large on-shore areas in the adjacent central south Sicily.
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contemporary tectonic stress in northeastern iberia new results from Borehole Breakout analysis
Tectonophysics, 1997Co-Authors: Maria Jose Jurado, Birgit MüllerAbstract:Abstract In situ data on the orientation of tectonic stress in northern Iberia are scarce. Fault-slip and focal mechanism data show a variety of stress orientations difficult to interpret in terms of a general stress pattern. Breakout analysis performed on oriented caliper logs from 17 hydrocarbon exploration wells has provided new data on the orientation of tectonic stress in northeastern Iberia: the southern Pyrenees, the Ebro Basin and the northwestern Valencia Trough. The majority of Breakout data indicate a rather consistent NE-SW to ENE-WSW directional signature of the larger horizontal principal stress orientation. This orientation differs significantly from the NW western European mean stress orientation. It is consistent with depth within the first 4.7 km of both the sedimentary fill and the sedimentary basins substrate and also within allochthonous thrust sheets in the southern Pyrenees and in the underlying autochthonous and parautochthonous foreland basin sediments.
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European stress: contributions from Borehole Breakouts
Philosophical Transactions of the Royal Society A, 1991Co-Authors: Robin Brereton, Birgit MüllerAbstract:Before about 1986 European measurements of rock stresses were sparse. The development of the Borehole Breakout method has facilitated a dramatic increase in the geographical distribution of rock stress orientations. These are derived from data collected routinely for other purposes by the oil, coal and gas industries over many years. Borehole Breakouts can be interpreted in term s of the orientation of the stress field in Boreholes as a function of depth, with the findings related to known stratigraphical boundaries, tectonic structures, fault and fracture occurrences, and to other geological and geophysical stress indicators. Geographical and depth distributions of stress on local and regional scales are beginning to provide the necessary base from which broad interpretive stress field models can be constructed.
Bezalel C Haimson - One of the best experts on this subject based on the ideXlab platform.
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integrating Borehole Breakout dimensions strength criteria and leak off test results to constrain the state of stress across the chelungpu fault taiwan
Tectonophysics, 2010Co-Authors: Bezalel C Haimson, Jihhao Hung, Shengrong SongAbstract:article The paper describes the computation of the maximum horizontal stress (σH) magnitude in the vicinity of the Chelungpu Fault, Taiwan, host of the slip zone during the Chi-Chi earthquake (Mw 7.6; 1999). The scientific hole B intercepts the Chelungpu Fault at 1136 m. At the depths of logged Breakouts (940-1310 m), the vertical stress (σv) as estimated from density logs increases linearly with depth from 22 to 31 MPa. A series of leak-off tests yielded two reliable shut-in pressures, 23.7 MPa at 1085 m and 29.8 MPa at 1279 m, which are lower than the estimated σv, albeit by only 2.1 and 0.6 MPa, respectively. In our analysis the shut-in pressures were considered to represent estimates of the least horizontal principal stresses (σh) at the respective depths, and consequently the test-induced fractures were assumed to have been vertical. Principal stress directions had been previously determined by others (105°-155° for the maximum horizontal stress, σH,
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micromechanisms of Borehole instability leading to Breakouts in rocks
International Journal of Rock Mechanics and Mining Sciences, 2007Co-Authors: Bezalel C HaimsonAbstract:This paper reviews the different Borehole Breakout failure micromechanisms observed during a multiyear laboratory research effort at the University of Wisconsin. Vertical Borehole drilling experiments were conducted in a variety of granites, limestones, and sandstones under a wide range of pre-existing stress fields. Test samples that developed Breakouts during drilling were analyzed under optical and scanning electron microscopes to establish the micromechanics of failure. All rocks tested, except for the quartz-rich sandstones, develop dog-eared Breakouts along the minimum horizontal far-field stress springline, even though the grain-scale mechanisms leading to the final appearance may differ considerably. The common denominator is the incipient failure in the form of dilatant microcracking in the zones of the highest compressive stress concentration around the Borehole. Dependent on rock type, these microcracks could be tensile or shear openings, extending inter- or intra-granularly. A type of failure not hitherto recognized was discovered in quartz-rich sandstones, which develop tabular slot-shaped Breakouts that maintain a constant very narrow width over an extensive length, resulting in a fracture-like appearance. Such Breakouts are the result of a largely non-dilatant micromechanism consisting of localized grain debonding and repacking leading to the formation of an apparent reduced-porosity compaction band along the minimum horizontal far-field stress springline. Breakouts are produced by the removal, with the help of the circulating drilling fluid, of loose grains and grain fragments that were debonded in the process of compaction band forming.
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true triaxial strength of the ktb amphibolite under Borehole wall conditions and its use to estimate the maximum horizontal in situ stress
Journal of Geophysical Research, 2002Co-Authors: Bezalel C Haimson, Chandong ChangAbstract:[1] Estimation of the maximum horizontal in situ stress from logged Borehole-Breakout dimensions in brittle elastic rocks requires knowledge of the true triaxial compressive strength of the medium. We employed our true triaxial loading apparatus to determine the strength criterion of the nearly impermeable amphibolite penetrated by the German Continental Deep Drilling Program (KTB) superdeep scientific hole at depths of 3200–7800 m. To better simulate Borehole wall conditions, we left one pair of the prismatic specimens' faces unjacketed and in direct contact with the confining fluid. This testing variation brings about a fundamentally different failure mechanism from that in fully jacketed (dry) specimens. Brittle fracture occurs at or soon after dilatancy onset and results from the development of densely spaced extensile fractures subparallel and adjacent to one of the unjacketed faces. We infer that the confining fluid intrudes newly opened microcracks, which are predominantly subparallel to the unjacketed faces, and promotes their elongation into throughgoing fractures. For any given least principal stress, the compressive strength typically increases with the rise in the intermediate principal stress. The true triaxial strength criterion of the unjacketed amphibolite can be expressed as a linear relationship between the octahedral shear stress and the octahedral normal stress at failure. Employing this criterion together with all the other known data from the KTB hole, we recomputed the magnitude of the maximum horizontal in situ stress there. Our results show that it increases steadily with depth, with a relatively narrow band of uncertainty, confirming previous assessments of a strike-slip stress regime.
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Polyaxial strength criteria and their use in estimating in situ stress magnitudes from Borehole Breakout dimensions
International Journal of Rock Mechanics and Mining Sciences, 1997Co-Authors: Insun Song, Bezalel C HaimsonAbstract:Abstract We conducted laboratory simulation tests of Borehole Breakouts and investigated their potential use as an indicator of in situ stress magnitudes in Westerly granite and Berea sandstone. We also carried out simple triaxial tests and used the results to derive several strength criteria for these rocks. Using the assumption that the state of stress at the Breakout boundary on the Borehole wall is in a state of limit equilibrium with the rock strength, we attempted to determine the appropriate strength criterion for each of the two rocks. We concluded that the well known Mohr-Coulomb criterion is not compatible with the condition of stress at Breakout failure. On the other hand, truly triaxial (polyaxial) strength criteria, which incorporate the effect of the intermediate principal stress on failure, are much more in agreement with the stress at the Breakout boundary. One such criterion due to Nadai and another due to Mogi, appear suitable for determining Breakout failure in the sandstone and the granite, respectively. Thin-section analysis suggests that Breakout failure mechanism may play an important role in determining the appropriate strength criterion for a given rock type. Utilizing the appropriate strength criterion for the corresponding rock type, and having knowledge of the Breakout span at the Borehole wall and the minimum horizontal and vertical principal stresses, we were able to estimate the maximum far-field principal stress within an average of 14% error.
Germán Bottesi - One of the best experts on this subject based on the ideXlab platform.
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Contemporary stress orientations in the Andean retroarc between 34°S and 39°S from Borehole Breakout analysis
Tectonics, 2007Co-Authors: Cecilia Griselda Guzman, Ernesto O. Cristallini, Germán BottesiAbstract:[1] In this paper we present the results of the analysis of Borehole Breakouts from 115 wells drilled within Neuquen Basin in the Andean retroarc between 34° and 39°S (Argentina). The first-order present-day stress orientation in the Andean retroarc is expected to be mainly controlled by the plate boundary forces (azimuth 80°) and the topographic forces (E–W). The obtained maximum horizontal stress (SHmax) has a preferred trend with a resultant direction of azimuth 88.7° and a 95% confidence interval of 13.3° consistent with the expected trend. The horizontal stress trajectory map achieved for this region shows that the SHmax along the study area is not completely uniform. To the north of Colorado River, the SHmax shows an ESE tendency interpreted as significant influenced by the topographic forces. To the south of Colorado River, SHmax has an ENE trend similar to the expected based on plate boundary forces. To the southeast of the region, a NE direction was found, probably showing a basement structural control in the stress field geometry. The stress orientations obtained for the whole region show that plate boundary forces, drag basal, and topographic forces are strongly controlling the stress direction distribution.
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contemporary stress orientations in the andean retroarc between 34 s and 39 s from Borehole Breakout analysis
Tectonics, 2007Co-Authors: Cecilia Griselda Guzman, Ernesto O. Cristallini, Germán BottesiAbstract:[1] In this paper we present the results of the analysis of Borehole Breakouts from 115 wells drilled within Neuquen Basin in the Andean retroarc between 34° and 39°S (Argentina). The first-order present-day stress orientation in the Andean retroarc is expected to be mainly controlled by the plate boundary forces (azimuth 80°) and the topographic forces (E–W). The obtained maximum horizontal stress (SHmax) has a preferred trend with a resultant direction of azimuth 88.7° and a 95% confidence interval of 13.3° consistent with the expected trend. The horizontal stress trajectory map achieved for this region shows that the SHmax along the study area is not completely uniform. To the north of Colorado River, the SHmax shows an ESE tendency interpreted as significant influenced by the topographic forces. To the south of Colorado River, SHmax has an ENE trend similar to the expected based on plate boundary forces. To the southeast of the region, a NE direction was found, probably showing a basement structural control in the stress field geometry. The stress orientations obtained for the whole region show that plate boundary forces, drag basal, and topographic forces are strongly controlling the stress direction distribution.