Investigation of deposystems, sediment routing, and basin architecture during Gondwana breakup refines understanding of Permian–Cretaceous landscape evolution in the central Andes. New chronostratigraphic and provenance constraints from the Eastern Cordillera and Subandean Zone of Bolivia (19–22°S) are based on U-Pb geochronology of detrital and volcanic zircons and 40Ar/39Ar dating of interbedded basalts. A discontinuous <2 km-thick Permian–Cretaceous succession records deposition in fluvial, lacustrine, alluvial fan, eolian, and shallow marine environments. Stratigraphic correlations indicate alternations between isolated half-graben subbasins and regional, non-compartmentalized basins. Detrital zircon age spectra from 18 sandstones document sediment recycling from western orogenic and magmatic arc sources and eastern cratonic basement. Synextensional successions of Early Triassic, Early Jurassic, and mid-Cretaceous age were sourced mainly from the west, including Carboniferous and Devonian rocks, while post-extensional fluvial and eolian systems were derived chiefly from the eastern craton. Variations in thickness, facies, and mafic magmatism reflect alternating extensional and neutral tectonic regimes, with localized synextensional subsidence potentially linked to extensional collapse, mantle plume activity, and South Atlantic opening. Comparison with Andean regions in Peru and Argentina indicates that episodic extension and post-extensional thermal subsidence accompanied subduction along the western margin of South America during Gondwana-Pangea breakup.

Long sedimentary records from tropical lakes provide crucial archives for reconstructing the timing and extent of tropical alpine glaciations, yet robust chronologies beyond the radiocarbon limit (ca. 50 ka) remain scarce. Here, we refine the ca. 350 kyr chronology for Lake Titicaca (Peru-Bolivia) using radiocarbon dating, optically stimulated luminescence, and zircon combined U-Th and (U-Th)/He ages from volcanic ashes, enhanced by stratigraphic alignment to Lake Jun & iacute;n. New post-infrared infrared stimulated luminescence (pIRIR225) luminescence ages, constrained by sediment-specific water-content corrections, anchor a Bayesian age model extending reliably to similar to 350 ka. The new ages support the major features of the original chronologic framework for the Lake Titicaca drill core but shift ages in some older portions of the sequence. Alignment of magnetic susceptibility records between Titicaca and Jun & iacute;n sediments using dynamic time warping highlights clear regional coherence in Andean glacial maxima corresponding to Marine Isotope Stages 2, 6, and 8. These refined ages revise previous chronologies and underscore the sensitivity of tropical Andean glaciers to large-scale forcings associated with global climate cycles.

The Mexican orogen represents the southern continuation of the North American Cordilleran orogenic system and plays a critical role in shaping the tectonic, structural, and thermal evolution of western Mexico. Although the age of deformation in central and northern Mexico is continuously being constrained, deformation in southern Mexico remains poorly understood due to limited geochronological data. Thick-skinned structures exposed along the western margin of the Acatl & aacute;n Complex are interpreted as part of the Mexican orogen and, therefore, offer an important opportunity to refine the timing and tectonic evolution of deformation in southern Mexico. This study presents new zircon (U-Th)/He thermochronology data revealing Late Cretaceous deformation and exhumation along the western margin of the Acatl & aacute;n Complex. Field observations along the western margin of the Acatl & aacute;n Complex show that the southeast-dipping S1 foliation of metamorphic rocks is structurally parallel to the La Encinera Shear Zone main fabric, a Carboniferous ductile structure with complex deformation features. In contrast, the similarly oriented Papalutla Fault represents a Late Cretaceous brittle structure juxtaposing the Acatl & aacute;n Complex and the Guerrero-Morelos Platform, cross-cutting the thin-skinned structures of the platform. Zircon He data reveal two thermal events: (1) a post-Jurassic to pre-Cenomanian heating phase that partially reset the zircon He system, likely related to similar to 1.6 km of burial and regional increase of geothermal gradient, and (2) a cooling phase marking the onset of exhumation that started during the Cenomanian, predating initial deformation of the Mexican orogen and deposition of the Mezcala Formation west of the Acatl & aacute;n Complex.

The Barra Velha Formation is a prolific Aptian (Lower Cretaceous) oil and gas producer located in the Santos Basin, southeastern Brazilian coast. We used structural core description, petrography, geochemistry, and geochronology to show evidence from drill cores that the Barra Velha Formation was affected by several events of brittle deformation and interacting hydrothermal alteration. The U-Pb geochronology provides an age of ca. 116 Ma for depositional host rock calcites, although recrystallization is possible. An early brecciation event occurred at ca. 108 Ma. Recracked fractures (>10 cm wide) are interpreted as spring mound vents. A dolomite fault mineralization is dated at ca. 95 Ma. Events affecting fractures include widespread dissolution, with secondary porosity filled by barite, quartz, and solid bitumen. Fluid inclusion geochemistry suggests that diagenesis occurred with the participation of seawater. We show a timeline of diagenetic events and infer that fracture porosity is more likely to be preserved where deep faults enabled fluids from greater depths to ascend into the reservoir, where they created large vuggy cavities by dissolution of host rock.

Our understanding of the impact of melt generation and the interplay between magmatism and mechanical stretching during progressive rifting leading to seafloor spreading remains rudimentary. The Eastern North American Margin (ENAM) provides an excellent location to study the influence of rift magmatism on continental break‐up considering the preservation of ∼30 Myr of syn‐rift strata and voluminous basaltic dikes, sills, and flows. Previous studies mainly focused on magmatism preserved in ENAM rift basins, emphasizing Central Atlantic Magmatic Province activity. Aeromagnetic data sets show pervasive magmatism across the ENAM proximal domain in the form of dikes that largely remain undated. We present in situ apatite U‐Pb geochronology and whole‐rock geochemical data from diabase dikes along the ENAM to determine the temporal and chemical evolution of Mesozoic dike emplacement and evaluate whether these magmas were emplaced rapidly at ∼201 Ma or in episodic pulses during rifting and break‐up. New in situ apatite U‐Pb analyses collectively indicate multiple magmatism pulses along the proximal domain of the ENAM, clustering around ∼201, ∼180, and ∼150 Ma. A first pulse at the Triassic/Jurassic boundary is likely due to decompression melting of an enriched mantle, a second smaller pulse in the Early Jurassic potentially correlative to the Blake Spur Magnetic Anomaly and lithospheric breakup, and a third small pulse in the Early Jurassic potentially correlative to the transition to symmetric seafloor spreading. These results indicate that prolonged off‐axis magmatism is likely due to slow spreading rates driving delocalization of extension away from the rift axis into the proximal domain.

This study provides new constraints on the paleogeographic evolution of the Arctic during the Mesozoic. U–Pb geochronology of detrital zircon and rutile grains, together with (U–Th)/He zircon thermochronological data from the uppermost Middle Jurassic to Cretaceous strata of the Sverdrup well in the Kara Sea, reveals a major shift in sediment provenance. Two distinct age populations of detrital zircon define this transition: Group 1 (Middle Jurassic–Hauterivian) shows dominant Neoproterozoic–Cambrian (ca. 700–500 Ma) and Paleozoic (ca. 350–290 Ma) peaks, whereas Group 2 (Aptian–Albian) is characterized by prominent Paleoproterozoic (ca. 1980–1720 Ma), Paleozoic (ca. 350–255 Ma), and Early Mesozoic (ca. 240–115 Ma) ages. Corresponding variations in (U–Th)/He zircon ages—from a Triassic peak (~225 Ma) in Group 1 to a dominant Early Cretaceous peak (~140 Ma) in Group 2—support a switch from a proximal to more distal sediment source. We propose that the emergence of large continent-scale river systems transported clastic material from the southern margin of the Siberian Craton to the Arctic Ocean starting in the late Early Cretaceous. The development of a significant freshwater supply potentially initiated a thick low-salinity layer within the surface waters of the central Arctic Ocean, possibly leading to the onset of a strong salinity stratification of near-surface water masses as in the modern Arctic Ocean.

Geothermal plays in extensional and transtensional tectonic environments have long been a major target in the exploration of geothermal resources and the Dixie Valley area has served as a classic natural laboratory for this type of geothermal plays. In recent years, the interactions between normal faults and strike-slip faults, acting either as strain relay zones have attracted significant interest in geothermal exploration as they commonly result in fault-controlled dilational corners with enhanced fracture permeability and thus have the potential to host blind geothermal prospects. Structural ambiguity, complications in fault linkage, etc. often make the selection for geothermal exploration drilling targets complicated and risky. Though simplistic, the three main ingredients of a viable utility-grade geothermal resource are heat, fluids, and permeability. Our new geological mapping and fault kinematic analysis derived a structural model suggest a two-stage structural evolution with (a) middle Miocene N -S trending normal faults (faults cutting across the modern range), - and tiling Olio-Miocene volcanic and sedimentary sequences (similar in style to East Range and S Stillwater Range). NE-trending range-front normal faulting initiated during the Pliocene and are both truncating N-S trending normal faults and reactivating some former normal faults in a right-lateral fashion. Thus the two main fundamental differences to previous structural models are (1) N-S trending faults are pre-existing middle Miocene normal faults and (2) these faults are reactivated in a right-later fashion (NOT left-lateral) and kinematically linked to the younger NE-trending range-bounding normal faults (Pliocene in age). More importantly, this study provides the first constraints on transient fluid flow through the novel application of apatite (U-Th)/He (AHe) and 4He/3He thermochronometry in the geothermally active Dixie Valley area in Nevada.