Exploration Geoscience Research Articles

Geological controls of mineralization occurrences in the Egyptian Eastern Desert using advanced integration of remote sensing and magnetic data

This study presents a comprehensive analysis of mineralization exploration in the Egyptian Eastern Desert (ED), one of the most sought-after areas for those interested in mining industry, by integrating Landsat-9 images and geophysical magnetic data. Employing advanced techniques like Principal Component (PC) analysis, Minimum Noise Fraction (MNf) transform, and Band-Ratio (B-Ratio), the research focuses on mapping lithological units, hydrothermal alteration regions, and structural elements. Composite images derived from specific PC, and MNf bands, and B-Ratio exhibit superior lithological unit identification. The findings emphasize that there are significant variations in the types of rocks extend from the southern to the northern parts of the ED. Hydrothermal alteration mapping, guided by B-Ratio results, aids qualitative lithological discrimination. A novel false color composite image optimizes Landsat-9 B-Ratios, enhancing rock unit discrimination. Correlation analyses reveal associations between mineralization types and major lithological units, while exploration of the magnetic anomaly map highlights its role in correlating mineralization sites. Structural features, analyzed through Center for Exploration-Targeting Grid-Analysis (CET-GA) and Center for Exploration-Targeting Porphyry-Analysis (CET-GA) with Tilt Derivative of RTP (TDR) techniques, contribute to a robust association between regions with medium to high structural density and porphyry intrusions and mineralization. The study significantly supports the advanced exploration geoscience, providing insights into the geological structures and dynamics governing mineralization in the Egyptian ED.

Welcome to the Australasian Exploration Geoscience Conference 2023

Welcome to the Australasian Exploration Geoscience Conference 2023

Welcome to the third Australasian Exploration Geoscience Conference

Welcome to the third Australasian Exploration Geoscience Conference

ASEG Young Professionals Network: AEGC 2021 - overview of student and early career events and financial assistance

The 3rd Australasian Exploration Geoscience Conference (AEGC 2021) will be held in Brisbane from 15-20 September. We are pleased to announce that several student and early career focused events wil...

Deep Mediterranean's Messinian evaporite giant: How much salt?

Abstract Evaporite giants can precipitate out of high salinity waters in semi-enclosed ocean basins when the rate of evaporation outstrips the inflow of new saline and fresh waters. The thick saline series deposited in the deep Mediterranean during the Miocene Epoch's late Messinian age (between 5.97 and 5.3 Ma) is among the youngest of such salt giants in Earth history. During this event, also known as the Messinian Salinity Crisis, voluminous evaporites accumulated in the deep basins when the main inflow of saline water to the Mediterranean through the Gibraltar Straits was severely diminished. The evaporites are interbedded with sediments eroded from the shelves and slopes or mass-transported downslope. Recent advances in geochronology and better understanding of the geodynamic history of various basins have led to insights about the timing of the salinity crisis and the tectonics and role of Gibraltar passage and other western narrows from the Atlantic to the Mediterranean. New estimates based on ocean-wide seismic facies analysis presented here reveal that there is between 821 ± 50 and 927 ± 50 thousand cubic km of late Messinian salt, and a total of up to 1.2 ± 0.1 million cubic km of salt plus associated sediment tied up in the deep Mediterranean basins. This suggests that after the initial restriction the Mediterranean had to be either continuously supplied with brine, or partially to completely refilled several times to produce the total salt edifice. The amount of Atlantic saline water needed to amass this evaporite giant is between 7 and 8 times the modern-day Mediterranean's equivalent of saline water. Our new volumetric estimates have implications for the Mediterranean's Messinian sequestration and desiccation scenarios and should lead to more meaningful geodynamic models and provide constraints for many of the controversies that still surround this major event in geological history. Maps of salt distribution in various basins also have important implications for sub-salt exploration geoscience.

Revamping doctoral training for a decarbonised future

Revamping doctoral training for a decarbonised future

Welcome to the second Australasian Exploration Geoscience Conference

Welcome to the second Australasian Exploration Geoscience Conference

Australasian Exploration Geoscience Conference 2019: Set to be sell-out!

Australasian Exploration Geoscience Conference 2019: Set to be sell-out!

Flotation froth image recognition with convolutional neural networks

Computer vision systems designed for flotation froth image analysis are well established in industry, where their ability to measure froth flow velocities and stability are used to control recovery. However, the use of froth image analysis to estimate the concentrations of mineral species in the froth phase is less well established and the reliability of these algorithms depends on the quality of the features that can be extracted from the froth images. Over less than a decade, convolutional neural networks have significantly pushed the boundaries with regard to image recognition in range of technical applications, notably cancer diagnosis, face recognition, remote sensing, as well as applications in the food industry. With the exception of the exploration geosciences, they are yet to make meaningful inroads in the mineral process industries. In this study, the use of three pretrained neural networks architectures to estimate froth grades from industrial image data, namely AlexNet, VGG16 and ResNet is considered. In its pretrained format, AlexNet outperformed previously proposed methods by a significant margin. This margin could be increased markedly via partial retraining of the VGG16 and ResNet34 networks.

Creating a new frontier in detection and data integration for exploration through cover

A new wave of technologies and data products are needed to address the decline in greenfields exploration activity and discovery success in Australia. Australia is an old continent with much of its remaining mineral endowment obscured by a thick cover of weathered rock, sediment and soil materials. This presents a critical challenge for mineral exploration now and into the future, as the industry currently lacks the fundamental data, scientific knowledge and technological tools needed to discover new, world-class ore deposits buried beneath this cover. UNCOVER, is a national vision in Australia for the future for mineral exploration geoscience research to tackle the geological barriers to more tier 1 discoveries. Harnessing capabilities, a well-defined focus and virtuous collaboration on the task of developing this new technology coupled with strong industry engagement can address this challenge.

UNCOVER – Progress in the Vision for Exploration Geosciences and Mineral Discovery in Australia

UNCOVER – Progress in the Vision for Exploration Geosciences and Mineral Discovery in Australia

Generalized methods and solvers for noise removal from piecewise constant signals. I. Background theory

Removing noise from piecewise constant (PWC) signals is a challenging signal processing problem arising in many practical contexts. For example, in exploration geosciences, noisy drill hole records need to be separated into stratigraphic zones, and in biophysics, jumps between molecular dwell states have to be extracted from noisy fluorescence microscopy signals. Many PWC denoising methods exist, including total variation regularization, mean shift clustering, stepwise jump placement, running medians, convex clustering shrinkage and bilateral filtering; conventional linear signal processing methods are fundamentally unsuited. This paper (part I, the first of two) shows that most of these methods are associated with a special case of a generalized functional, minimized to achieve PWC denoising. The minimizer can be obtained by diverse solver algorithms, including stepwise jump placement, convex programming, finite differences, iterated running medians, least angle regression, regularization path following and coordinate descent. In the second paper, part II, we introduce novel PWC denoising methods, and comparisons between these methods performed on synthetic and real signals, showing that the new understanding of the problem gained in part I leads to new methods that have a useful role to play.

Petroleum exploration history: discovery pattern versus manpower, technology and the development of exploration principles

Discovery of conventional resources outside North America peaked during 1956–1980, when almost 60% out of the total 3535 Bbbloe of technically recoverable resources discovered through 2007 were found. Most of the 88 super-giant fields were also found during that period. How does this clear pattern of discovery compare with the patterns of development of the organizations, technologies and principles employed in petroleum exploration geoscience? Since 1900 the organizations involved in exploration have become steadily more numerous and diverse, as have the geoscientists employed, but both were affected by the oil price shock in 1985. The technologies for drilling and well geosciences evolved steadily. Similarly, seismic reflection technology, starting in 1920, has progressed relentlessly. Geochemical technologies, to analyse source rocks, their maturation and hydrocarbon generation, developed rapidly from 1970. Three ‘principles’ of petroleum exploration geoscience have been developed: the search for anticlinal traps replaced drilling on seeps in the 1930s; the exploration play was formulated in 1984; and the more general principle of the petroleum system was formulated in 1988. This history shows that the pattern of discovery and the patterns of manpower, technology and the development of principles have followed different paths in the period since 1900.

Non-seismic technology

5 articles regarding the Special Topic: 'Non-seismic technolgy': -'Role of airborne geophysical reconnaissance in exploration geoscience', by Colin Reeves -'Advances continue in gravity and magnetic data technology for marine seismic surveys', by Mark Weber -'Oil exploration from space: fewer places to hide', by Derek Fairhead, Chris Green and William Dickson -'Value of gravity and magnetic surveys in exploration of the North West European Continental Shelf, 1945-75', by Derek Morris -'Effective use of non-seismic methods for petroleum exploration', by John Ceron, C. Lombo, Stephen Williams and John Bain

Abstract :Exploration and Development Geoscience in the 21st Century: How to Survive, How to Thrive?

Abstract :Exploration and Development Geoscience in the 21st Century: How to Survive, How to Thrive?

Petroleum Hydrogeology of the Cooper and Eromanga Basins, Australia: Some Insights from Mathematical Modeling and Fluid Inclusion Data

Mathematical modeling and fluid inclusion data analysis are used to reconstruct the petroleum hydrogeology of the Australian Cooper and Eromanga basins. Our analysis focuses on the development of topography- and compaction-driven groundwater flow systems and their role in heat redistribution, petroleum generation, and oil and brine migration during basin evolution. Finite-element models of basin transport processes are constructed along northeast-southwest (AA´) and northwest-southeast (BB´) cross sections that generally follow the present-day groundwater flow patterns through these basins. Numerical results are presented in the ©Copyright 1997. The American Association of Petroleum Geologists. All rights reserved.1Manuscript received September 19, 1995; revised manuscript received July 3, 1996; final acceptance November 11, 1996. 2Independent Consultant, 12 Rinzee Road, Dracut, Massachusetts 01826. 3CSIRO Division of Petroleum Exploration, 51 Delhi Road, North Ryde, NSW 2113, Australia. 4Department of Geology and Geophysics, University of Minnesota, 310 Pillsbury Drive SE, Minneapolis, Minnesota 55455 (E-mail: mperson@ darcy.geo.umn.edu) 5GZA GeoEnvironmental Inc., 380 Harvey Road, Manchester, New Hampshire 03103. 6Santos Ltd., 101 Grenfell Street, Adelaide, SA 7000, Australia. This research is supported by a grant from the Petroleum Research Fund, administered by the American Chemical Society, PRF 24184-AC8. We would also like to acknowledge the Orpha and George Gibson Hydrogeology Endowment and the McKnight Land-Grant Professorship Program at the University of Minnesota. We thank the CSIRO Division of Exploration Geosciences for providing support for travel costs within Australia. Data provided by Santos Ltd. and the Department of Mines and Energy, South Australia, are also gratefully acknowledged. Computational work performed on this project was done at the Gibson Computational Hydrogeology Laboratory at the University of Minnesota, which is supported by the National Science Foundation under EAR 94-05807. Special thanks go to M. A. Habermehl of the Australian Geological Survey Organization, David Gravestock of the South Australia Bureau of Mines and Mineral Resources, and Mike Congreves of Santos Ltd. for their assistance on interpreting the petroleum geology and hydrogeology of the Cooper and Eromanga basins. The review comments of Joseph Toth, Stefan Bachu, and Michelle Walvoord, as well as discussions with Ward Sanford, greatly improved the quality of this manuscript. Three-dimensional model results presented in this paper are available in animated form on VHS videocassette and can be obtained by contacting Mark Person at the address listed for him as the corresponding author.

SALTMAP — Airborne EM for the Environment

There is increasing recognition that electrical conductivity is an important diagnostic parameter of the near-surface in the applications of land degradation monitoring, ground-water exploration and geological mapping. Airborne electromagnetic (AEM) geophysical surveys provide a means of measurement of ground-conductivity distributions. SALTMAP, a new AEM survey system being developed in Australia by World Geoscience Corporation and the CSIRO Divisions of Exploration Geoscience and Water Resources, has been designed specifically to make high-resolution measurements of the conductivity distribution within the regolith. This results from the broadband nature of the transmitter and receiver antennae and high-speed signal processing incorporated in SALTMAP. SALTMAP will record secondary fields at frequencies in excess of 50 kHz ? unprecedented for a broadband AEM system ? enabling measurement of near-surface conductivity distributions. In resistive terrain, SALTMAP's specifications give it a unique ability to discriminate mineral exploration targets to some depth. As a result of the broad bandwidth of SALTMAP, it is susceptible to a wide range of interference problems which can be overcome only with powerful signal processing equipment that has only recently become available. A three-component receiver antenna has been incorporated in SALTMAP to provide full measurement of the secondary field. All SALTMAP components are under the control of flexible computer algorithms to enable SALTMAP to be adapted to a wide range of applications in a wide range of conditions. SALTMAP provides a powerful new tool for land and water resource authorities and mineral explorers. It will provide detailed information about the hydrogeology over large areas at a fraction of the cost of normal land treatments. Improved interpretation of regolith conditions will result in a significant increase in efficiency of implementation of strategies for sustainable land use and rehabilitation.

Notes On Rock Magnetization Characteristics In Applied Geophysical Studies

The magnetic method is firmly established as an investigative procedure in applied geophysics, and it is increasingly recognised that an understanding of the elements of magnetic petrophysics assists in optimising field data interpretations. These notes expand on the rock magnetism data previously presented by Emerson (1979) and Clark (1983); the data presented are based on magnetic property studies in the CSIRO Division of Exploration Geoscience and the Department of Geology and Geophysics University of Sydney and on published studies and compilations. The systematic collection of petrophysical data by many workers over the last decade has greatly expanded the size and scope of available data. Works listed in the Bibliography should be consulted for further information.

Research in exploration geoscience: The AMIRA model

The paper summarises the exploration related R&D that has been managed by AMIRA/APIRA and gives details of the complex, market oriented process used to develop new projects.The process is illustrated by three case studies taken from the more than 70 exploration projects completed.The Gold Deposits of North Queensland Project conducted by James Cook University studied the various styles of gold mineralization. The Rock Magnetism project undertaken at CSIRO Division of Exploration Geoscience allowed both general and specific research themes to be undertaken in parallel with confidential proprietary investigations on sponsors' drill core. The Palaeogeographic Mapping project undertaken at the BMR Division of Continental Geology provided sponsors with palaeogeographic maps including interpretation and structural information of 70 time slices.Some of the benefits of the AMIRA/APIRA approach are discussed as well as some of the difficulties which arise in ensuring companies obtain appropriate benefits from their sponsorship.