The Ramsay-Graham heterogeneous simple shear zone model revolutionized our understanding of finite strain variation in orogenic belts. Many deeply exhumed (>20 km depths) zones continental crust are a consequence sub-simple accumulation during contraction and displacement at high temperature. Here we explore the micro-scale record this process using syn-kinematic monazite two >20,000 km2 terran...

• Ultrahigh pressure (UHP) eclogite is absent from the rock record before c. 0.6 Ga. Continental crust (CC) has experienced secular change, becoming more felsic with time. Mafic Archean CC becomes too dense to exhume UHP conditions are reached. More mafic would have been submerged by a global ocean 1.3 km deep. Implications for hypotheses requiring subaerial land emergence of life. The absence ...

The Altiplano-Puna Magma Body (APMB) in the Central Andes is the largest imaged magma reservoir on Earth, and is located within the second highest orogenic plateau on Earth, the Altiplano-Puna. Although the APMB is a first-order geologic feature similar to the Sierra Nevada batholith, its role in the surface uplift history of the Central Andes remains uncertain. Here we show that a long-wavelen...

Taiwan is a young orogenic belt with complex spatial distributions of deformation and earthquakes. We have constructed a three-dimensional finite element model to explore how the interplays between lithospheric structure and plate boundary processes control the distribution of stress and strain rates in the Taiwan region. The model assumes a liberalized power-law rheology and incorporates main ...

Highlighting how crustal shortening is accommodated in space and time fold-thrust belts a major issue for understanding the long-term tectonic evolution of orogenic systems. In this study, we combine surface subsurface data to build 150 km-long sequentially restored balanced cross-section across two superimposed foreland southeastern France: upper Cretaceous-Eocene Provençal belt Oligocene-Neog...

The southern part of the West African Craton includes Baoulé-Mossi Domain, world’s premier Paleoproterozoic gold province (~10,000 metric ton endowment). Structural, metamorphic, and geochronological data suggest mineralisation occurred during three episodes that span much Eoeburnean Eburnean orogenic cycles. rare skarn-hosted deposits formed between ca. 2200 2135 Ma repeated volcanism, plutoni...

Focused groundwater discharge in closed basins provides opportunities to investigate mechanisms for closing hydrologic and solute budgets in arid regions. The Salar de Atacama (SdA), adjacent to the Central Andean Plateau in the hyperarid Atacama Desert, provides an extreme example of halite (>1800 km) and lithium brine (~5000 ppm) accumulation spanning late Miocene to present. Minimum long-ter...

Precambrian quartzo-feldspathic gneiss was encountered at an elevation of —3616 feet in the Herman 1A well drilled in southeastern Erie County, Ohio, by the Amerada Petroleum Corporation. The five samples of this gneiss that were studied exhibit varying degrees of gneissose foliation. In order of decreasing abundance, microcline, plagioclase, quartz, and biotite together account for an average ...

[1] Mechanistic theories of fluvial erosion are essential for quantifying large-scale orogenic denudation. We examine the topographic implications of two leading classes of river erosion model, detachment-limited and transport-limited, in order to identify diagnostic and testable differences between them. Several formulations predict distinctly different longitudinal profile shapes, which are s...