Publications

Terra Nova: The Louisiade ophiolite: A missing link in the western Pacific

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Recent dredging of a 100 km long ridge along the northernmost part of the Louisiade Plateau (LP) recovered serpentinized peridotites, MORB (mid-ocean-ridge basalt) and volcaniclastic breccia–conglomerates. Clinopyroxene, Cr-spinel and bulk rocks show that the serpentinites are harzburgites to dunites, whereas hornblende phenocrysts from volcaniclastic rocks reflect hydrous, andesitic volcanism. The association of MORB, depleted mantle rocks … Read more…

Geochemical anomaly definition using stream sediments landscape modeling

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A new research paper published in Ore Geology Reviews based on a collaboration between Dr. Behnam Sadeghi from EarthByte Group, USYD, and several research institutes in China, including: China University of Geosciences: State Key Laboratory of Geological Processes and Mineral Resources Hebei GEO University: 1) Institute of Resource and Environmental Engineering, 2) Hebei Key Laboratory … Read more…

Nature Geoscience: Dynamics of the abrupt change in Pacific Plate motion around 50 million years ago

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A drastic change in plate tectonics and mantle convection occurred around 50 Ma as exemplified by the prominent Hawaiian– Emperor Bend. Both an abrupt Pacific Plate motion change and a change in mantle plume dynamics have been proposed to account for the Hawaiian–Emperor Bend, but debates surround the relative contribution of the two mechanisms. Here … Read more…

Scientific Reports: The evolution of basal mantle structure in response to supercontinent aggregation and dispersal

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Seismic studies have revealed two Large Low-Shear Velocity Provinces (LLSVPs) in the lowermost mantle. Whether these structures remain stable over time or evolve through supercontinent cycles is debated. Here we analyze a recently published mantle flow model constrained by a synthetic plate motion model extending back to one billion years ago, to investigate how the … Read more…

Special Issue: Mineral exploration: a journey from fieldwork, to laboratory work, computational modelling and mineral processing

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Dr. Behnam Sadeghi from EarthByte Group, and Profs. Astrid Holzheid (Christian-Albrechts-Universität Kiel, Germany) and Hongbo Zhao (Central South University, China) organised a new Special Issue for the journal “Geochemistry” (former “Chemie der Erde”) in 2021, which has been published recently. This SI has covered some topics in mineral exploration, including fieldwork, laboratory work, computational modelling, … Read more…

PNAS: High 3He/4He in central Panama reveals a distal connection to the Galapagos plume

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Significance We report the discovery of anomalously high 3He/4He in “cold” geothermal fluids of central Panama, far from any active volcanoes. Combined with independent constraints from lava geochemistry, mantle source geochemical anomalies in Central America require a Galapagos plume contribution that is not derived from hotspot track recycling. Instead, these signals likely originate from large-scale … Read more…

Communications Earth & Environment: Quaternary landscape dynamics boosted species dispersal across Southeast Asia

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Sundaland, the inundated shelf separating Java, Sumatra and Borneo from the Malay Peninsula, is of exceptional interest to biogeographers for its species richness and its position at the junction between the Australasian and Indomalay biogeographic provinces. Owing to its low elevation and relief, its physiography is contingent on relative sea-level change, which drove Quaternary species … Read more…

Detection of mineralization stages using zonality and multifractal modeling based on geological and geochemical data in the Au-(Cu) intrusion-related Gouzal-Bolagh deposit, NW Iran

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As the co- and corresponding author, Dr. Behnam Sadeghi, from EarthByte Group, has recently published this paper in “Ore Geology Reviews”. This research is based on a collaborative project with the Geological Survey of Iran. Abstract: The objective of this paper is to detect various gold and copper mineralization stages according to surface lithogeochemical data … Read more…

Remote Sensing of the Enivronment: A review of machine learning in processing remote sensing data for mineral exploration

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The decline of the number of newly discovered mineral deposits and increase in demand for different minerals in recent years has led exploration geologists to look for more efficient and innovative methods for processing different data types at each stage of mineral exploration. As a primary step, various features, such as lithological units, alteration types, … Read more…

Earth Surface Dynamics: Tectonically and climatically driven mountain-hopping erosion in central Guatemala from detrital 10Be and river profile analysis

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The rise of a mountain range affects moisture circulation in the atmosphere and water runoff across the land surface, modifying the distribution of precipitation and drainage patterns in its vicinity. Water routing in turn affects erosion on hillslopes and incision in river channels on surrounding mountain ranges. In central Guatemala, two parallel, closely spaced mountain … Read more…

Geosphere: Fast Pliocene integration of the Central Anatolian Plateau drainage: Evidence, processes, and driving forces

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Continental sedimentation was widespread across the Central Anatolian Plateau in Miocene– Pliocene time, during the early stages of plateau uplift. Today, however, most sediment produced on the plateau is dispersed by a well-integrated drainage and released into surrounding marine depocenters. Residual long-term (106–107 yr) sediment storage on the plateau is now restricted to a few … Read more…

Marine and Petroleum Geology: Single-phase vs two-phase rifting: Numerical perspectives on the accommodation of extension during continental break-up

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How continental lithosphere responds to extension is a function of the dynamic interaction between layers of differing rheological properties, including the shallow crust, deep crust, lithospheric mantle, and asthenosphere. We investigate the first-order controls on the modes of extension and timing of transition from continental rifting to development of continental margins via a suite of … Read more…

Basin Research: Modelling the role of dynamic topography and eustasy in the evolution of the Great Artesian Basin

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Widespread flooding of the Australian continent during the Early Cretaceous, referred to as the Eromanga Sea, deposited extensive shallow marine sediments throughout the Great Artesian Basin (GAB). This event had been considered ‘out of sync’ with eustatic sea level and was instead solely attributed to dynamic subsidence associated with Australia’s passage over eastern Gondwanan subducted … Read more…

Modelling global precipitation since 250 million years ago

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We have developed a novel data-driven approach to reconstruct precipitation patterns through geological time, since the supercontinent Pangea was in existence. Our approach involves linking climate-sensitive sedimentary deposits such as coal, evaporites and glacial deposits to a global plate model, reconstructed paleo-elevation maps and high-resolution General Circulation Models via Bayesian machine learning. We model the … Read more…

Simulated-multifractal models: A futuristic review of multifractal modeling in geochemical anomaly classification

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Dr. Behnam Sadeghi, from EarthByte Group (USYD), has published a new review paper in “Ore Geology Reviews”. Sadeghi et al. (2015) proposed simulated-fractal models for the first time, which is based on the combination of geostatistical simulation models and mathematical fractal/multifractal modeling to classify geochemical anomalies. Based on that research, several other models have been … Read more…

G-Cubed: Papanin Ridge and Ojin Rise Seamounts (Northwest Pacific): Dual Hotspot Tracks Formed by the Shatsky Plume

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The origin of Shatsky Rise, a large igneous plateau in the NW Pacific, has long been debated. It could have either formed by shallow mantle melting due to its confirmed creation along a mid-ocean ridge or with additional contribution of deeper mantle material that upwelled as so-called mantle plume beneath the spreading ridge (“plume-ridge interaction”). … Read more…

Continental arcs dominate global chemical weathering

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Earth’s plate-tectonic activity regulates the carbon cycle and, hence, climate, via volcanic outgassing and silicate-rock weather- ing. Mountain building, arc–continent collisions and clustering of continents in the tropics have all been invoked as controlling the weathering flux, with arcs also acting as a major contributor of carbon dioxide to the atmosphere. However, these processes have … Read more…

Kinematics and extent of the Piemont–Liguria Basin – implications for subduction processes in the Alps

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Assessing the size of a former ocean of which only remnants are found in mountain belts is challenging but crucial to understanding subduction and exhumation processes. Here we present new constraints on the opening and width of the Piemont–Liguria (PL) Ocean, known as the Alpine Tethys together with the Valais Basin. We use a regional … Read more…

Predicting the emplacement of Cordilleran porphyry copper systems using a spatio-temporal machine learning model

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Porphyry copper (Cu) systems occur along magmatic belts derived in subduction zones. Our current under- standing of their formation is restricted to observations from the overriding plate, resulting in a knowledge gap in terms of processes occurring in convergence zones through time. An association between key tectonic processes and the timing and location of porphyry … Read more…

Potential encoding of coupling between Milankovitch forcing and Earth’s interior processes in the Phanerozoic eustatic sea-level record

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The driving mechanisms of Earth’s climate system at a multi-Myr timescale have received considerable attention since the 1980’s as they are deemed to control large-amplitude climatic variations that result in severe biogeochemical disruptions, major sea-level variations, and the evolution of Earth’s land- and seascapes through geological time. The commonly accepted mechanism for these changes derives … Read more…

Concentration-distance from centroids (C-DC) multifractal modeling: A novel approach to characterizing geochemical patterns based on sample distance from mineralization

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Behnam Sadeghi from EarthByte Group has published a new paper in journal “Ore Geology Reviews”, based on his PhD thesis. In this research, to explore the VMS Cu deposits throughout Sweden a novel multifractal model of concentration-distance from centroids (C-DC) has been developed and applied to the till data provided by the Geological Survey of … Read more…

Mantle plumes and their role in Earth processes

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The existence of mantle plumes was first proposed in the 1970s to explain intra-plate, hotspot volcanism, yet owing to difficulties in resolving mantle upwellings with geophysical images and discrepancies in interpretations of geochemical and geochronological data, the origin, dynamics and composition of plumes and their links to plate tectonics are still contested. In a recently … Read more…

Geochemical anomaly definition using multifractal modeling, validated by geological field observations: Siah Jangal area, SE Iran

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Dr. Behnam Sadeghi from EarthByte Group has published this paper recently in the journal “Geochemistry-Chemie der Erde” (Special Issue of “Mineral exploration: a journey from fieldwork, to laboratory work, computational modelling and mineral processing”). This research is part of a research project with the University of Neyshabur, which has been done in SE Iran. Abstract … Read more…

SPS Model: a significant algorithm to reduce the time and computer memory required in geostatistical simulations

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Behnam Sadeghi has published this paper in the Iranian Journal of Earth Sciences. In this research, he has developed an algorithm to down-scale the maps, to reduce the simulation time and the required memory, but to keep the same geostatistical performance and accuracy. This model strongly helps with huge and time-consuming simulations. Abstract In geochemical … Read more…

The carbonate compensation depth in the South Atlantic Ocean since the Late Cretaceous

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Carbonate accumulation rates (CAR) in the South Atlantic through time, with the average CCD for the South Atlantic shown in black, which the CCD in the Walvis Ridge/Rio Grande Rise area is shown in magenta. Deep-sea carbonate deposition is a complex process that is encapsulated in the carbonate compensation depth (CCD)—a facies boundary separating calcareous … Read more…

Weighting of BLEG data with drainage and catchment properties to enhance Au anomalies

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Weighting of BLEG data with drainage and catchment properties to enhance Au anomalies Dr. Behnam Sadeghi with Profs. Huseyin Yilmaz and Franco Pirajno, has published this paper in journal “Geochemistry/Chemie der Erde”, based on bulk leachable extractable gold (BLEG) data in Western Turkey, considering several other relevant parameters such catchments’ areas, slopes and curvatures plus … Read more…

Category-based fractal modelling: A novel model to integrate the geology into the data for more effective processing and interpretation

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Category-based fractal modelling: A novel model to integrate the geology into the data for more effective processing and interpretation Dr. Behnam Sadeghi and his PhD supervisor, Prof. David Cohen, has published another paper in Journal of Geochemical Exploration. This paper is based on his PhD thesis. In this research, they have proposed two novel fractal … Read more…

Intraplate volcanism triggered by bursts in slab flux

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Long-lived, widespread intraplate volcanism without age progression is one of the most controversial features of plate tectonics. Previously proposed edge-driven convection, asthenospheric shear, and lithospheric detachment fail to explain the ~5000-km-wide intraplate volcanic province from eastern Australia to Zealandia. We model the subducted slab volume over 100 million years and find that slab flux drives … Read more…

Coupled evolution of plate tectonics and basal mantle structure

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The relationships between plate motions and basal mantle structure remain poorly understood, with some models implying that the basal mantle structure has remained stable over time, while others suggest that it could be shaped by the aggregation and dispersal of supercontinents. Here we investigate the evolution of mantle flow driven by end‐member plate tectonic models … Read more…

Paper in Frontiers of Earth Science: Modeling the Dynamic Landscape Evolution of a Volcanic Coastal Environment Under Future Climate Trajectories

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Modeling the Dynamic Landscape Evolution of a Volcanic Coastal Environment Under Future Climate Trajectories Kyle Manley, T. Salles and R. D. Müller As anthropogenic forcing continues to rapidly modify worldwide climate, impacts on landscape changes will grow. Olivine weathering is a natural process that sequesters carbon out of the atmosphere, but is now being proposed … Read more…