Earth Science Research Research Articles

Reviewer Acknowledgements for Earth Science Research, Vol. 9, No. 2

Reviewer Acknowledgements for Earth Science Research, Vol. 9, No. 2, 2020.

Earth science research on Marion Island (1996–2020): a synthesis and new findings

ABSTRACT Marion Island is a peak of a shield volcano located in the southern Indian Ocean. The island is strategically important for the collection of climatological data and marine and terrestrial research in a vast, oceanic region of the globe. This paper reviews the series of earth science programmes on Marion Island over the last 25 years, provides a synthesis of the research outcomes and demonstrates how field and laboratory methods have developed over time. Marion Island has, globally, one of the most active soil frost environments in a distinctive periglacial setting and understanding this contemporary periglacial environment has been a key objective of the research programmes. Geomorphological processes have important implications for local ecosystem functioning and define the regional and global significance for diurnal soil frost environments and climate change. Keeping abreast with the advancements of appropriate methodologies and technologies and the continued employment of a mix of new and established methods has driven the earth science research in this unique island environment. A series of short vignettes present the most recent advancements on old key questions and indicate that new techniques continuously challenge us to re-evaluate the most basic of assumptions that exist within our research.

NSF Plots a Course for the Next Decade of Earth Sciences Research

Committee members who put together the new report Earth in Time describe this as an “all hands on deck” moment for the field.

Comparison of pipette method and state of the art analytical techniques to determine granulometric properties of sediments and soils

The determination of particle size distribution is a crucial issue in various fields of earth sciences (e.g., Quaternary research, sedimentology, stratigraphy, structural geology, volcanology), environmental sciences as well as diverse industrial applications (e.g., pharmaceuticals, cement industry). New measurement techniques developed as a result of industrial demands have also gained ground in environmental and Earth sciences research. The new techniques (especially laser diffraction) have enabled the particle characterisation in the broader size-range with a more detailed resolution. Still, they have to be compared with data obtained by classical methods. In light of the above, the primary aim of our research is to examine the methods of particle size determination critically. Excessive oversimplifications of particle size analyses routinely have used in paleo-environmental and paleo-climatological reconstructions, and other sedimentary studies, as well as insufficient knowledge of the background of the applied methods, distort the interpretation of the results. Over the past four decades, laser diffraction particle size analysers have proven to be practical tools of particle size characterisation. However, the shape of the natural sediment and soil particles are irregular and, therefore, affects the particle size distribution results obtained by different methods. The results of the traditional pipette method differed from laser diffraction results. The presence or absence of the pretreatments did control the differences between the two techniques. The results of Fraunhofer optical method were significantly different from Mie theory because it can detect much lower volume percentages of finer particles. Grain size results of coarse-grained samples measured by different laser diffraction devices were more comparable than the results of more clayey samples. The ratios of different sizes were changed due to the hydrochloric acid and hydrogen peroxide pretreatments. The comparison of different techniques is necessary to revaluate standards in grain size measurements which can enable the shift from conventional methods to more productive and reproducible methods. Still, light scattering techniques have not yet been able to displace classical methods in Earth sciences completely, in contrast to industrial applications.

Identification of subsurface fluid flow using the 2D geoelectric method in Marunda, North Jakarta

Jakarta is the most densely populated province in Indonesia and it will grow over time. This overwhelming population causes a decrease in the quality and supply of groundwater. Brines has been discovered in several areas in Jakarta. Several studies conducted by earth science researchers conclude that brine in Jakarta appears from either seawater intrusion or trapped connate water. This study focuses on the use of the geoelectric method to evaluate the groundwater quality problem in Kelurahan Marunda. Methods used in this study are resistivity, self-potential, and groundwater sampling. Conductivity, Salinity, pH and water table elevation are the parameters used in this study. These methods are done to observe subsurface groundwater quality, fluid flow and how far the seawater infiltrated. Based on the result of groundwater data of 40 wells, high conductivity and high salinity zones are found. High conductivity in this area affected mostly by the saline factor indicated by high salinity and neutral pH. The subsoil has low resistivity values showed by 2D resistivity data. Also, self-potential data displays a North-South groundwater subsurface fluid flow 1, 20 km from the coastline. Altogether, these data indicate seawater intrusion in Kelurahan Marunda, North Jakarta.

Impact of land use changes on catchment soil erosion and sediment yield in the northeastern China: A panel data model application

Land use is an important factor influencing soil erosion and sediment yield (SESY). Regressing soil erosion intensity (SEI) and sediment yield (SY) to land use characteristics can provide necessary information for controlling soil loss. However, current simple regression methods emphasize cross sectional parameters, with less emphasis on temporal variability of relevant land use parameters so that the derived effects of land use change on SESY can be biased. Here, a panel data method was applied to quantify the impact of land use change on SESY in 1954, 1975, and 2015, based on the WaTEM/SEDEM model and seven landscape metrics for 25 reservoir catchments in northeastern China. The results indicate that SEI and area-specific SY (SSY) continuously decreased from 1954 to 2015, which were significantly correlated with landscape metrics such as area-edge metrics of mean patch area (AREA_MN), shape index of the mean related circumscribing circle (CIRCLE_MN), aggregation index of effective mesh size (MESH), patch cohesion index (COHESION), and diversity metrics such as Shannon's diversity index (SHDI), patch richness density (PRD), and modified Simpson's evenness index (MSIEI). The results suggested that catchment SESY can be reduced through decreasing mean patch area, patch mesh size, and physical connectivity of patches, enriching landscape types, and elongating land use patches. These findings are helpful to effectively implement soil conservation measures in northeastern China and similar regions worldwide. The current study also implies that the panel data approach will have beneficial potential applications in earth-science research fields.

Andy Green Receives 2019 Africa Award for Research Excellence in Ocean Sciences

Andy Green was awarded the 2019 Africa Award for Research Excellence in Ocean Sciences at the AGU Fall Meeting Honors Ceremony, held on 11 December 2019 in San Francisco, Calif. The award is given in recognition of “significant work that shows the focus and promise of making outstanding contributions to research in Earth or ocean sciences.”

Experimental fluid-mediated alteration of zircon under lower greenschist facies conditions

ABSTRACT The use of zircon in the dating of geological processes and tectonic events has become a standard approach in many aspects of Earth science research. As a result, understanding how zircon interacts with aqueous fluids during metasomatism has become increasingly important. The alteration of natural zircon is driven primarily by coupled dissolution–reprecipitation or by ion-exchange with an aqueous fluid. In this study, whole and intact, euhedral light-brown zircon crystals (100–250 μm in length; 2 mg) from the Oligocene Fish Canyon Tuff (FCT) were experimentally reacted with an alkali-bearing reactive fluid and a REE + P source (0.5 mg CePO4 or 0.5 mg YPO4). Experiments were conducted in sealed Au metal capsules at 350 °C and 100 MPa for 182 days. During the experiment, the zircon became colorless, indicating annealing of the radiation damage in the crystal. Two-dimensional element maps of the outermost 3 μm of unpolished zircon crystal surfaces were produced using a grind of contiguous 7 μm analytical spots via laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The chemical maps indicate that the surface of the zircon crystals from each experiment heterogeneously reacted with the fluid, such that the Ce and Y concentration of chemically modified areas increased (by an order of magnitude) in the CePO4-bearing and YPO4-bearing experiments, respectively, when compared with the chemical maps of unaltered zircon grain surfaces. Helium ion microscopy of polished crystals revealed discontinuous micron-scale altered domains at the crystal margin, consistent with the findings of the unpolished mapping technique. Interestingly, the Th and U concentration of the altered zircon grain surfaces were consistent with the unaltered zircon regardless of the experiment. Incorporation of REEs on the zircon grain surface likely occurred via the coupled substitution REE3+ + P5+ ↔ Zr4+ + Si4+. The results from these experiments imply that the surfaces of minimally metamict zircon can be chemically modified by alkali-bearing fluids via ion exchange under lower greenschist pressures and temperatures over relatively short time periods with respect to the geological time scale.

Reviewer Acknowledgements for Earth Science Research, Vol. 9, No. 1

Earth Science Research wishes to acknowledge the following individuals for their assistance with peer review of manuscripts for this issue. Their help and contributions in maintaining the quality of the journal is greatly appreciated.
 
 Earth Science Research is recruiting reviewers for the journal. If you are interested in becoming a reviewer, we welcome you to join us. Please find the application form and details at http://www.ccsenet.org/reviewer and e-mail the completed application form to esr@ccsenet.org.
 
 Reviewers for Volume 9, Number 1
 
 Bahareh Shoghli, University Of North Dakota, USA
 
 Esmat Ahmed Abou El-Anwar, National Research Centre, Egypt
 
 Fehmi ARIKAN, General Directorate of Mineral Research and Exploration Company, Turkey
 
 Helber Gomes, Federal University of São Paulo and Center for Weather Forecasting and Climate Research, Brazil
 
 Iyad Ahmed Abboud, Taibah University, Jordan
 
 Khalid Ubeid, Al-Azhar University-Gaza, Palestine
 
 P. Sathees Kumar, Mohamed Sathak Engineering College, INDIA
 
 Sanjeet Kumar Verma, University of Campinas, Brazil
 
 Saumitra Misra, University of KwaZulu-Natal, South Africa

Kuljeet Kaur Marhas Receives 2019 Devendra Lal Memorial Medal

Kuljeet Kaur Marhas was awarded the 2019 Devendra Lal Memorial Medal at the AGU Fall Meeting Honors Ceremony, held on 11 December 2019 in San Francisco, Calif. The medal is for “outstanding Earth and/or space sciences research by a scientist belonging to and working in a developing country.”

A Method for the Optimized Design of a Rain Gauge Network Combined with Satellite Remote Sensing Data

A well-designed rain gauge network can provide precise and detailed rainfall data for earth science research; meanwhile, satellite precipitation data has been developed to generate more real spatial features, which provides new data support for the improvement of ground station network design methods. In this paper, satellite precipitation data are introduced into the design of a rain gauge network and an optimized method for designing a rain gauge network that comprehensively considers the information content, spatiotemporality, and accuracy (ISA) of the data is proposed. After screening the potential stations, the average spatial information index of the rain gauge network, which is calculated from remote sensing data, is used to address the shortcomings of applying spatial information from single-use measurement data. Then, the greedy ranking algorithm is used to rank the order in which the rain gauges are added to the network. The results of the rain gauge network design in the upper reaches of the Chaobai river show that compared with two methods that do not consider spatiality or use only measured data to consider spatiality, the proposed method performs better in terms of the spatial layout and accuracy verification. This study provides new ideas and references for the design of hydrological station networks and explores the use of remote sensing data for the layout of ground-based station networks.

New evidence of the Suess/de Vries cycle existing in historical naked-eye observations of sunspots

AbstractSolar activity affects geophysical and heliophysical processes. Long-term changes in solar activity are closely related to climate change. Solar physicists and earth science researchers need longer observations of solar activity. Current continuous observations of solar activity are only about 400 years. Some scholars have compiled naked-eye observations of sunspots from 200 BC to 1918 AD from historical documents. In this present work, the authors use the weighted wavelet transform to study the observations series. The results show the Suess - de Vries cycle with a period from 195- to 235-year existing in the discontinuous sunspot series. Meanwhile, the cycle signal changes with time. Especially, the Suess/de Vries cycle is relatively obvious from 200 BC to 400 AD, 800 AD to 1340 AD, 1610 AD to 1918 AD, with a period of about 211-year, about 195-year, and about 235-year, respectively.

Where is geoscience going?

Abstract This short article provides my views – and not necessarily views that are shared by the British Geological Survey, where I was executive director from 2006–19, or by the Earth science community in general. I have outlined some of the trends that I see as important for the geosciences, largely from a solid-Earth perspective. I stress that fundamental discovery science in this sector must be, and will largely continue to be, led by the academic community but that Earth sciences research needs to be more focused on problem solving rather than refining our knowledge of the problems that face the Earth system. Academics and government laboratories have distinct but complementary roles in the pursuit of discovery and in applied geoscience research and training of geoscientists.

Building the future of the geoscience community in Asia: CCOP beyond history and borders

Abstract The Coordinating Committee for Geoscience Programmes in East and SE Asia (CCOP) is an intergovernmental geoscience organization based in Bangkok, Thailand. CCOP currently comprises 15 member countries in East and SE Asia; it has provided venues for various geoscientific programmes and activities in the region for over 50 years. At its inception, CCOP conducted work in geological surveys, exploration and technological cooperation in the extraction of off-shore petroleum and mineral resources in the region. In response to the needs of member countries, CCOP projects have become increasingly diverse over time, especially in the areas of groundwater resources, geohazards, global climate change and urban geology. Facing the imminent fourth industrial revolution, CCOP compiles, manages and utilizes large amounts of data collected and accumulated by its member countries, and increasingly focusses on data sharing, education and capacity building. With the vision of becoming a premier intergovernmental Earth science organization in East and SE Asia, CCOP's mission is the application of Earth science to make significant contributions to the economic development and sustainable environmental management of its member countries, enhancing their quality of life. To fulfil this mission, CCOP has developed four strategic foci: (1) outreach; (2) cooperation and partnership; (3) knowledge enhancement and sharing; and (4) data and information. Organization and management of CCOP are governed by a steering committee formed of permanent representatives from the 15 member countries and guided by recommendations from an advisory group comprising representatives from cooperating countries and organizations. The steering committee considers and endorses projects and activities planned and proposed by the technical secretariat, which oversees the management of the organization, implementing all approved plans for the benefit of all member countries as well as cooperating countries and organizations. CCOP has played important roles in providing venues for activities and collaboration on various Earth science topics, including energy and mineral resources, groundwater, geohazards, global climate change, urban geology, geoscience big data, education and outreach. CCOP also publishes regular and special publications describing its activities. In the future, CCOP will encourage non-members in the region to join as official member countries, and will further strengthen its network by conducting joint Earth science research projects with cooperating countries and organizations. CCOP will also pursue sustainability in research by establishing a system to continually nurture new Earth scientists. Furthermore, CCOP will build a cooperative network with geoscience communities in other regions to promote a sustainable Earth.

The modern geological survey: a model for research, innovation, synthesis. A USGS perspective

Abstract Geological surveys have long filled the role of providing Earth system science data and knowledge. These functions are increasingly complicated by accelerating environmental and societal change. Here we describe the US Geological Survey (USGS) response to these evolving conditions. Underpinning the USGS approach is the recognition that many of the issues facing the USA and the world involve interaction among geological, hydrological and biological processes, and how these interactions in turn affect society. Therefore, a goal of USGS planning is fostering interdisciplinary science. This focus is occurring in part through implementation of the recommendations of strategic planning teams. The USGS has also put in place groups building a broad information technology infrastructure as well as identifying and disseminating new Earth science research tools. In addition, the USGS has established an analysis and synthesis centre that brings together groups of scientists who address interdisciplinary Earth system science issues. The goal is for these building blocks to evolve towards a comprehensive USGS data and knowledge platform – EarthMAP (Earth Monitoring, Assessment, and Projection). We also recognize that the modern geological survey must be a member of a community of geological surveys contributing data to a global database of three-dimensional biogeophysical observations and interpretations.

Geological surveys as research-focused organizations: New Zealand's experience and opportunities

Abstract GNS Science is New Zealand's geological survey with an applied earth science research focus yet without traditional government department accountabilities. As one of New Zealand's Crown Research Institutes established in 1992, GNS Science is owned by the New Zealand Government but has higher levels of self-determination, fiscal independence and impartiality than a government department. Securing competitive research funding and commissioned research is a business imperative and because of this the institute is able to respond and adapt to changing societal expectations. GNS Science can also influence outcomes based on its discretionary research investment. New Zealand's geological setting astride an active plate boundary attracts many international partners endeavouring to better understand geological processes in an accessible and logistically well-resourced natural laboratory. Partnerships like these substantially increase technological and financial resources and these enable diverse and often ambitious projects.

Casting Octahedra for Reproducible Multi-Anvil Experiments by 3D-Printed Molds

Making consistent and precise octahedral pressure media is crucial for reproducible high-pressure experiments in the multi-anvil press. Here we report a new approach of casting octahedra using 3D-printed molds, and pressure calibrations for octahedra both with and without pre-existing gaskets (“fins”). The 3D-printed molds for casting octahedra from either Ceramacast 584-OF or 646 cement improve the reproducibility of the octahedra and allow for a pre-existing central hole (for the high-pressure cell assembly) in the final cast product. Pressure and temperature calibrations of the octahedra have been performed based on phase transitions in bismuth (Bi) and silica (SiO2), respectively, in order to determine the efficiency and reproducibility of pressure generation and thermal insulation for cast octahedra designed for use with 18/12, 14/8, and 10/5 multi-anvil assemblies. The pressure-generating efficiency of the 14/8 and 10/5 octahedra with pre-existing gaskets, cast from the 584-OF cement, is similar to that of the corresponding COMPRES (Consortium for Materials Properties Research in Earth Sciences) octahedra, and more efficient than pre-cast octahedra made from the same material but lacking pre-existing gaskets. The efficiency of pre-gasketed 18/12 octahedra made of the 646 cement is markedly lower than those of the 584 cement. However, the 18/12 large-volume octahedra, cast (with fins) from the ZrO2-based 646 cement, also provides efficient thermal insulation. Casting octahedral solid pressure media for multi-anvil experiments using 3D-printed “injection” molds is a low-cost and low failure-rate alternative for conducting reproducible experiments at high pressure in the multi-anvil apparatus.

Optimization of SIMS analytical parameters for water content measurement of olivine

Secondary ion mass spectrometry (SIMS) has a wide range of applications in Earth Science research, thanks to its high precision and sensitivity, and its capacity in direct insitu micromeasurement. The technique is operated in ultra‐high vacuum (UHV) conditions, especially for the measurement of volatiles such as hydrogen, or the water content in nominally anhydrous minerals (NAMs). To minimize the water background and obtain accurate and precise water contents in NAMs (eg, olivine) critical parameters such as presputtering time, field aperture (FA), dynamic transfer on/off, and primary beam current intensity were investigated for a CAMECA IMS 1280‐HR system. When the chamber vacuum reaches approximately 2 × 10−9 mbar, we set the DTOS OFF, raster size to 50 μm and primary beam current to 5 nA, and used 2000 μm FA and 170‐second presputtering time. Consequently, an approximately 1.2 ppmw water background and 3.6 ppmw limit of detection (LOD) were yielded, from analyzing the San Carlos olivine. Meanwhile, the water content and homogeneity of a range of olivine minerals were characterized for potential use as reference materials for SIMS water content measurement. Olivine water content calibration curve was also established by comparing the Fourier transform infrared (FTIR) results with the SIMS‐measured 16O1H−/16O− ratios. Accuracy and precision of water content measurement were estimated to be better than approximately 10% in this study.

Analysis of Long-Term Moon-Based Observation Characteristics for Arctic and Antarctic

The Antarctic and Arctic have always been critical areas of earth science research and are sensitive to global climate change. Global climate change exhibits diversity characteristics on both temporal and spatial scales. Since the Moon-based earth observation platform could provide large-scale, multi-angle, and long-term measurements complementary to the satellite-based Earth observation data, it is necessary to study the observation characteristics of this new platform. With deepening understanding of Moon-based observations, we have seen its good observation ability in the middle and low latitudes of the Earth’s surface, but for polar regions, we need to further study the observation characteristics of this platform. Based on the above objectives, we used the Moon-based Earth observation geometric model to quantify the geometric relationship between the Sun, Moon, and Earth. Assuming the sensor is at the center of the nearside of the Moon, the coverage characteristics of the earth feature points are counted. The observation intervals, access frequency, and the angle information of each point during 100 years were obtained, and the variation rule was analyzed. The research showed that the lunar platform could carry out ideal observations for the polar regions. For the North and South poles, a continuous observation duration of 14.5 days could be obtained, and as the latitude decreased, the duration time was reduced to less than one day at the latitude of 65° in each hemisphere. The dominant observation time of the North Pole is concentrated from mid-March to mid-September, and for the South Pole, it is the rest of the year, and as the latitude decreases, it extends outward from both sides. The annual coverage time and frequency will change with the relationship between the Moon and the Earth. This study also proves that the Moon-based observation has multi-angle observation advantages for the Arctic and the Antarctic areas, which can help better understand large-scale geoscientific phenomena. The above findings indicate that the Moon-based observation can be applied as a new type of remote sensing technology to the observation field of the Earth’s polar regions.

The lithospheric structure and deep processes of the Mesozoic mineral systems in east China: constrained from integrated geophysical data

Financed by the SinoProbe, a national collaborative multidisciplinary Earth science research project in China, the authors has conducted multi-scale and integrated geophysical exploration across th...