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During rifting, pre‐existing penetrative basement fabrics can affect new faults in cover rocks by a mechanism that does not appear to involve reactivation. This subtle form of inheritance can significantly impact fault network architecture in rift basins above laterally variable basement domains with geomechanical anisotropies. Here we use multi‐layer, brittle‐ductile, crustal‐scale analogue experiments to study the influence of penetrative basement anisotropies on fault patterns in the overlying cover during a single phase of orthogonal rifting. The experiments were designed to test whether basement anisotropies, oriented 45° to the extension direction, can lead to the formation of rift faults that are oblique to both the imposed extension direction and basement anisotropies. Our experiments show that a penetrative, vertically layered, mm‐wide basement anisotropy creates extension‐oblique faults in the overlying cover. We interpret this to arise when local strike‐slip kinematics along the interfaces of mechanically contrasting materials in the basement combine with the regional imposed orthogonal extension, creating a transtensional regime. The width and spacing of alternating "strong" and "weak" basement zones interact with rift kinematics, impacting the orientation, kinematics and spacing of new faults in the cover. New insights on the influence of penetrative, pre‐existing basement fabrics on localized re‐orientation of 3D strain in the cover have implications for understanding complex fault systems in rift basins and transfer zones. Key Points: Analogue models of rifting demonstrate how extension‐oblique faults in cover rocks are inherited from penetrative basement anisotropiesThe width and spacing of basement anisotropies impact the distribution, orientation, and kinematics of faults in the coverWe invoke strain re‐orientation as the mechanism for inheritance as opposed to direct reactivation of basement weaknesses [ABSTRACT FROM AUTHOR]

Pre-existing structures in the crust such as shear zones, faults, and mobile belts are known to exert a significant control on the structural evolution of continental rifts. However, the influence of such features when the extension direction progressively changes over time remains uncertain. Here we present new results from three-dimensional lithospheric-scale laboratory experiments of rotational extension that provide key insights into the temporal evolution of propagating rifts. We specifically test and characterize how rifts propagate and interact with linear crustal rheological heterogeneities oriented at variable angles with respect to the extension direction. Results show that approximately rift-parallel pre-existing heterogeneities favor the formation of long, linear faults that reach near-final lengths at early stages. Low angles between the heterogeneities and the propagating rift axis may result in strong strikeslip reactivation of the pre-existing structures if they are suitably oriented with respect to the stretching direction. When the linear heterogeneities are oriented at intermediate to high angles rift branches become laterally offset as they propagate, resulting in complex rhombic fault patterns. Rift-perpendicular crustal heterogeneities do not affect fault trends during rift propagation, but cause stalling and deepening of laterally growing rift basins. Similarities between the analogue experimental results and selected natural examples provide insights on how nature finds the preferential pathway to breakup in heterogeneous continental lithosphere. [ABSTRACT FROM AUTHOR]

Microcontinents occur outboard of passive margins and stranded in ocean basins. Threedimensional analogue laboratory experiments of continental rifting demonstrate that microcontinent formation at passive margins requires a combination of preexisting linear weaknesses in the lithosphere and rotational extension. Our results suggest that separation of microcontinents from passive margins occurs during the latest stages of continental breakup, before the onset of seafloor spreading, and that preexisting lithospheric weaknesses are a first-order control on where they form. These findings suggest that microcontinent formation may be restricted to localized regions along passive margins associated with zones of lithospheric weakness, providing a new structural and tectonic framework for the interpretation of microcontinents in the geological record. [ABSTRACT FROM AUTHOR]

The Red Sea represents an incipient ocean basin that is in transition from continental rifting to ocean initiation. In this paper we assess how pre-existing mantle and crustal heterogeneities within the African and Arabian lithospheres influenced rift development and propagation using three-dimensional (3D) brittle-ductile analogue laboratory experiments with a rotational boundary condition. Here we investigate the effect of three different configurations: (i) pre-existing rheological heterogeneities in the crust, (ii) in the lithospheric mantle, and (iii) in both. The experimental outcomes show that a linear weak zone in the lithospheric mantle layer exerts a first-order control on the overall mechanical behaviour of extending lithosphere, rift architecture and style of rifting. Crustal heterogeneities control second-order features, such as the trends of the main boundary escarpments along the rift axis. Our experiments reproduce the geological history of the Red Sea and provide key insights on its deformation history in space and time. We provide, for the first time, 3D dynamic constraints on how pre-existing weak zones in the lithosphere have controlled the temporal evolution of the Red Sea and determined its distinctive present-day morphology. The results find that certain morphological elements of the Red Sea can only be explained by the combined effects of crustal and mantle lithosphere heterogeneities. When applied to other natural examples, our findings provide significant new insights on the role of crustal and lithospheric heterogeneities during continental rifting. • Models offer high-resolution spatio-temporal evolution of continental rifts. • Degree of control of linear weak zones in continental rifts is elucidated. • Superimposed crust and mantle weak zones control temporal evolution of the Red Sea. • Analogue models of rotational rifting explain the distinctive shape of the Red Sea. • Large-scale morphological features related to Gondwana break-up are explained. [ABSTRACT FROM AUTHOR]

The current project sought to examine the psychometric properties of a personality based measure (Substance Use Risk Profile Scale; SURPS: introversion-hopelessness, anxiety sensitivity, impulsivity, and sensation seeking) designed to differentially predict substance use preferences and patterns by matching primary personality-based motives for use to the specific effects of various psychoactive substances. Specifically, we sought to validate the SURPS in a clinical sample of substance users using cue reactivity methodology to assess current inclinations to consume a wide range of psychoactive substances. Using confirmatory factor analysis and correlational analyses, the SURPS demonstrated good psychometric properties and construct validity. Further, impulsivity and sensation-seeking were associated with use of multiple substances but could be differentiated by motives for use and susceptibility to the reinforcing effects of stimulants (i.e., impulsivity) and alcohol (i.e. sensation-seeking). In contrast, introversion-hopelessness and anxiety sensitivity demonstrated a pattern of use more focused on reducing negative affect, but were not differentiated based on specific patterns of use. Taken together, results suggests that among those receiving inpatient treatment for substance use disorders, the SURPS is a valid instrument for measuring four distinct personality dimensions that may be sensitive to motivational susceptibilities to specific patterns of alcohol and drug use.