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1. How should a clever baboon choose and move rocks?

Author:
Celesté Maré; Marietjie Landman; Graham I. H. Kerley
Source:
Biotropica 2021 v.53 no.1 pp. 162-169
ISSN:
0006-3606
Subject:
Papio ursinus; energy; landscapes
Abstract:
... Chacma baboons (Papio ursinus) intentionally overturn rocks to feed on the invertebrates beneath. However, baboons do not move all the rocks they encounter, with this presumably reflecting cost–benefit (or effort–reward) trade‐offs in their foraging behavior. We ask, how do “clever baboons” choose rock sizes and shapes and move these rocks? Using optimal foraging theory, we predicted that baboons ...
DOI:
10.1111/btp.12857

2. Temporal-spatial analysis of alkaline rocks based on GEOROC

Author:
Mingming Zhang; Chengbao Wang; Qi Zhang; Yufan Qin; Jingya Shen; Xunyu Hu; Guoyu Zhou; Siyang Li
Source:
Applied geochemistry 2021 v.124 pp. 104853
ISSN:
0883-2927
Subject:
Cenozoic era; Mesozoic era; Paleozoic era; databases; geochemistry; statistical analysis; tectonics
Abstract:
... Alkaline rocks account for a small proportion of magmatic rocks with characteristics of the linear distribution, and can reveal the tectonic setting and in source mantle compositions. Based on the GEOROC global geochemical database, we studied the temporal-spatial evolution of alkaline rocks in the world through GIS spatial analysis and data statistical analysis techniques. The results show ...
DOI:
10.1016/j.apgeochem.2020.104853

3. Interfacial interactions between scale-brine and various reservoir rocks

Author:
Amir Hossein Nikoo; M. Reza Malayeri
Source:
Colloids and surfaces 2021 v.611 pp. 125840
ISSN:
0927-7757
Subject:
anhydrite; calcite; calcium; dolomite; energy; gypsum; oils; salinity; sandstone
Abstract:
... The efficiency of water injection, as a conventional approach to enhance oil recovery, can profoundly be compromised due to detrimental impacts of scale formation. The present study discerns the interfacial interactions of brine with anhydrite, calcite, dolomite, and sandstone rock surfaces leading to gypsum scale formation. This was fulfilled using experimental jar tests at different salinities ...
DOI:
10.1016/j.colsurfa.2020.125840

4. Water ‘on the rocks’: a summer drink for thirsty trees?

Author:
Andrea Nardini; Francesco Petruzzellis; Daniel Marusig; Martina Tomasella; Sara Natale; Alfredo Altobelli; Chiara Calligaris; Gabriele Floriddia; Franco Cucchi; Emanuele Forte; Luca Zini
Source:
new phytologist 2021 v.229 no.1 pp. 199-212
ISSN:
0028-646X
Subject:
Fraxinus ornus; bedrock; biomass; canopy; dieback; dolomitic limestone; drought; drought tolerance; intraspecific variation; landscapes; porosity; soil; summer; tree mortality; water content; water storage; water stress
Abstract:
... Drought‐induced tree mortality frequently occurs in patches with different spatial and temporal distributions, which is only partly explained by inter‐ and intraspecific variation in drought tolerance. We investigated whether bedrock properties, with special reference to rock water storage capacity, affects tree water status and drought response in a rock‐dominated landscape. We measured primary ...
DOI:
10.1111/nph.16859

5. Zircon U–Pb chronology on plutonic rocks from northeastern Cambodia

Author:
Naoto Kasahara; Sota Niki; Etsuo Uchida; Kosei Yarimizu; Rathborith Cheng; Takafumi Hirata
Source:
Heliyon 2021 v.7 no.4 pp. e06752
ISSN:
2405-8440
Subject:
Early Cretaceous epoch; Permian period; Triassic period; geochronology; subduction; zircon; Cambodia; Vietnam
Abstract:
... Zircon U–Pb geochronology was carried out on plutonic rocks from Phnom Daek, Phnom Koy Rmeas, Svay Chras, Kon Mom, Koh Nheak, Andong Meas, Oyadav South, Svay Leu, and Phnom Soporkaley. The zircon U–Pb ages from the plutonic rocks determined in this study can be roughly divided into two groups. One is the Late Permian to Triassic ages of 278–202 Ma for the Phnom Daek, Phnom Koy Rmeas, Oyadav South ...
DOI:
10.1016/j.heliyon.2021.e06752

6. Application of percolation theory to microtomography of rocks

Author:
Jie Liu; Klaus Regenauer-Lieb
Source:
Earth-science reviews 2021 v.214 pp. 103519
ISSN:
0012-8252
Subject:
computed tomography; deformation; fractal dimensions; geophysics; mathematical theory; permeability; thermodynamics
Abstract:
... , the most popular application of percolation theory is the analysis of fluid flow in porous media. The capability to image the 3D structure of such porous networks through Computed Tomography (CT) opens new avenues for the concise application of percolation theory. Here we summarize digital rock techniques developed to derive rock properties and the critical percolation parameter from CT-scans and compare ...
DOI:
10.1016/j.earscirev.2021.103519

7. Monoterpenylabietenoids, novel biomarkers from extant and fossil Taxodioideae and sedimentary rocks

Author:
Bernd R.T. Simoneit; Maciej Rybicki; Magdalena Goryl; Michał Bucha; Angelika Otto; Leszek Marynowski
Source:
Organic geochemistry 2021 v.154 pp. 104172
ISSN:
0146-6380
Subject:
Cenozoic era; Cretaceous period; Jurassic period; biomarkers; dehydrogenation; diterpenoids; fossils; gas chromatography-mass spectrometry; geochemistry; organic matter; reflectance; thermal stability
Abstract:
... -cymenyldehydroabietane. The other tentatively assigned aromatic hydrocarbons were 9,10-p-cymenylretene and 9-p-cymenylsimonellite, which were present in Upper Cretaceous and Lower Jurassic sedimentary rocks with their further dehydrogenation products. Diterpenoid dimers were also tentatively identified in trace amounts, with 11- and 14-ferruginylferruginol as the dominant compounds. Our results show that the p ...
DOI:
10.1016/j.orggeochem.2020.104172

8. CrVI and Trace Element Contaminated Groundwater Systems Connected with Ophiolitic Rocks

Author:
Z. Hatipoglu-Bagci; C. S. Bayari
Source:
Bulletin of environmental contamination and toxicology 2021 v.106 no.3 pp. 415-420
ISSN:
0007-4861
Subject:
carbonates; chromium; groundwater; hydrochemistry; risk; serpentinite; toxicology
Abstract:
... of CrVI under Italian regulations. The dominant water facies are Ca–HCO₃ and Mg–HCO₃ types based on the Piper diagram. The Ca–HCO₃ type waters originate mainly from interaction with carbonate rocks, and the Mg–HCO₃ type waters originate from serpentinite dissolution. Chromium contents are higher in Mg–HCO₃ water types and the highest concentrations are found in samples from ophiolitic rocks ...
DOI:
10.1007/s00128-020-02887-w

9. Failure characteristics of surrounding rocks along the radial direction of underground excavations: An experimental study

Author:
Jianqing Jiang; Xia-Ting Feng; Chengxiang Yang; Guoshao Su
Source:
Engineering geology 2021 v.281 pp. 105984
ISSN:
0013-7952
Subject:
rocks,   etc   ; cracking; engineering; engineers; exhibitions; mass; wills;     Show all 7 Subjects
Abstract:
... For the in situ surrounding rocks of underground excavations, the radial stress corresponding to the minimum principal stress σ₃ varies with increasing distance away from the excavated boundary. To characterize the rock failure along the radial direction of an excavation, true triaxial compression tests with different σ₃ values (0.5, 5, 10, 15, 20, 25, and 30 MPa) were performed ...
DOI:
10.1016/j.enggeo.2020.105984

10. Beyond the extremes: Rocks as ultimate refuge for fungi in drylands

Author:
Claudia Coleine; Jason E. Stajich; Asunción de los Ríos; Laura Selbmann
Source:
Mycologia 2021 v.113 no.1 pp. 108-133
ISSN:
1557-2536
Subject:
arid lands; climate change; desertification; deserts; drought; ecosystems; evolution; extremophiles; habitats; surveys; taxonomy; Antarctic region
Abstract:
... In an era of rapid climate change and expansion of desertification, the extremely harsh conditions of drylands are a true challenge for microbial life. Under drought conditions, where most life forms cannot survive, rocks represent the main refuge for life. Indeed, the endolithic habitat provides thermal buffering, physical stability, and protection against incident ultraviolet (UV) radiation ...
DOI:
10.1080/00275514.2020.1816761

11. Processes in mushes and their role in the differentiation of granitic rocks

Author:
Roberto F. Weinberg; Ron H. Vernon; Harro Schmeling
Source:
Earth-science reviews 2021 v.220 pp. 103665
ISSN:
0012-8252
Subject:
crystallization; evolution; hybridization; liquefaction; porosity
Abstract:
... The modification of magma through mixing or through assimilation of country rocks is commonly inferred from various chemical and isotopic features of magmatic rock suites and supported by a variety of field evidence, including features indicative of interaction between two magmas, disaggregation of solids in magma, and varied antecryst populations in volcanic and plutonic rocks. The increased ...
DOI:
10.1016/j.earscirev.2021.103665

12. The responses of weathering carbon sink to eco-hydrological processes in global rocks

Author:
Huipeng Xi; Shijie Wang; Xiaoyong Bai; Hong Tang; Guangjie Luo; Huiwen Li; Luhua Wu; Chaojun Li; Huan Chen; Chen Ran; Xuling Luo
Source:
Science of the total environment 2021 v.788 pp. 147706
ISSN:
0048-9697
Subject:
carbon dioxide; carbon sinks; carbonates; data quality; environment; fossil fuels; hydrologic cycle; models; soil water; temperate zones; temperature
Abstract:
... Eco-hydrological processes affect the chemical weathering carbon sink (CS) of rocks. However, due to data quality limitations, the magnitude of the CS of rocks and their responses to eco-hydrological processes are not accurately understood. Therefore, based on Global Erosion Model for CO₂ fluxes (GEM-CO₂ model), hydrological site data, and multi-source remote sensing data, we produced a 0.05 ...
DOI:
10.1016/j.scitotenv.2021.147706

13. An advanced grain-based model to characterize mechanical behaviors of crystalline rocks with different weathering degrees

Author:
Xiaolin Huang; Shengwen Qi; Bowen Zheng; Ning Liang; Lihui Li; Lei Xue; Songfeng Guo; Xiang Sun; Daping Tai
Source:
Engineering geology 2021 v.280 pp. 105951
ISSN:
0013-7952
Subject:
rocks,   etc   ; cracking; elastic deformation; engineering; engineers; grains; laboratory experimentation; mechanical models; mechanical properties; microstructure; soil weathering; weather; weathering;     Show all 13 Subjects
Abstract:
... Laboratory tests revealed that by enhancing the weathering degree, a transition of pre-peak stress-strain mechanical responses of crystalline rocks under unconfined compression from approximate linearity to nonlinearity was evident, as was the weakening of macro-mechanical properties. However, thus far, very few numerical studies have been conducted to quantitatively characterize the strong ...
DOI:
10.1016/j.enggeo.2020.105951

14. Flow and Permeability Evolution during Microbial Sulfate Reduction and Inhibition in Fractured Rocks

Author:
Yiwei Cheng; Chunwei Chou; Marco Voltolini; Sharon Borglin; Jonathan B. Ajo-Franklin; Yuxin Wu
Source:
Energy & fuels 2021 v.35 no.3 pp. 1989-1997
ISSN:
1520-5029
Subject:
biofilm; energy; nitrates; nutrient transport; permeability; regrowth; sandstone; sulfates; sulfides
Abstract:
... Subsurface biological processes, such as biofilm development, modify flow and permeability in fractured rocks, greatly impacting energy production or treatment efficiencies. This study aims to understand biological–hydrological interactions at a bench scale during the progression and treatment of souring (microbially mediated sulfide production). Few bench-scale studies investigate the role ...
DOI:
10.1021/acs.energyfuels.0c01787

15. Effective Se reduction by lactate-stimulated indigenous microbial communities in excavated waste rocks

Author:
Tomo Aoyagi; Yoshihiko Mori; Mai Nanao; Yusuke Matsuyama; Yuya Sato; Tomohiro Inaba; Hidenobu Aizawa; Takayuki Hayakawa; Masahiko Moriya; Yasuhide Higo; Hiroshi Habe; Tomoyuki Hori
Source:
Journal of hazardous materials 2021 v.403 pp. 123908
ISSN:
0304-3894
Subject:
Brevibacillus; Desulfitobacterium hafniense; Desulfosporosinus; Pelosinus; acetates; genes; lactic acid; metabolites; metalloids; oxidation; propionic acid; selenium
Abstract:
... Waste rocks generated from tunnel excavation contain the metalloid selenium (Se) and its concentration sometimes exceeds the environmental standards. The possibility and effectiveness of dissolved Se removal by the indigenous microorganisms are unknown. Chemical analyses and high-throughput 16S rRNA gene sequencing were implemented to investigate the functional and structural responses ...
DOI:
10.1016/j.jhazmat.2020.123908

16. Radiogenic heat production in crustal quarry rocks of Ogun State, south-western, Nigeria

Author:
F. O. Ogunsanwo; J. O. Adepitan; J. D. Ayanda; K. W. Giwa; E. O. Falayi; A. I. Adejimi
Source:
Environmental earth sciences 2021 v.80 no.7 pp. 282
ISSN:
1866-6280
Subject:
alluvium; bedrock; coastal plains; heat production; limestone; potassium; quarries; radiometry; sand; shale; surveys; thorium; uranium; Nigeria
Abstract:
... Radiometric survey has been used extensively in quite a lot of fields of science, majorly for geological mapping and mineral exploration. It is used to quantify the proportion of potassium, uranium and thorium in rock and soil. Radiogenic heat production was found to be associated with the radioactive emission from the three primordial radioelements: uranium, thorium and potassium. In this study ...
DOI:
10.1007/s12665-021-09578-7

17. Bioweathering of Zn–Pb-bearing rocks: Experimental exposure to water, microorganisms, and root exudates

Author:
Maciej Swęd; Anna Potysz; Agata Duczmal-Czernikiewicz; Marcin Siepak; Wojciech Bartz
Source:
Applied geochemistry 2021 v.130 pp. 104966
ISSN:
0883-2927
Subject:
Acidithiobacillus thiooxidans; geochemistry; goethite; microbial growth; quartz; risk; smithsonite; soil; soil solution; Poland
Abstract:
... Zn–Pb-bearing rocks from mining sites in Olkusz, southern Poland may continue to represent a risk to the environment through the mobilization of metals. This study experimentally simulated the exposure of calamine-type rocks and goethite crusts to various weathering conditions and then compared the behavior of these mineralogically diverse samples. Study conditions included sample exposures ...
DOI:
10.1016/j.apgeochem.2021.104966

18. Thallium shifts the bacterial and fungal community structures in thallium mine waste rocks

Author:
Enzong Xiao; Zengping Ning; Weimin Sun; Shiming Jiang; Wenjun Fan; Liang Ma; Tangfu Xiao
Source:
Environmental pollution 2021 v.268 pp. 115834
ISSN:
0269-7491
Subject:
United States Environmental Protection Agency; fungal communities; fungi; metalloids; microbiome; pollutants; pollution; regression analysis; thallium; toxicity; China
Abstract:
... waste rocks in southwestern China. Our results showed that Tl had an important, but different influence on the bacterial and fungal diversity indices. Using linear regression analysis, we furtherly divided the dominant bacterial and fungal groups into three distinct microbial sub-communities thriving at high, moderate, and low levels of Tl. Furthermore, our results also showed that Tl is also ...
DOI:
10.1016/j.envpol.2020.115834

19. “A Gem among the Rocks”—Identifying and Measuring Visual Preferences for Mountain Lakes

Author:
Uta Schirpke; Rocco Scolozzi; Ulrike Tappeiner
Source:
Water 2021 v.13 no.9 pp. -
ISSN:
2073-4441
Subject:
aesthetics; cold; color; decision making; forests; lakes; land cover; landscapes; people; qualitative analysis; questionnaires; water; water quality
Abstract:
... and the absence of algae as well as large rocks at the lake shore and forest around the lake. In particular, preferences related to visual water characteristics were highly homogeneous across socio-cultural groups and confirmed previous findings. To illustrate the applicability of our findings, we integrated our results with spatial and limnological data to quantify aesthetic values for four selected study ...
DOI:
10.3390/w13091151

20. Impact of flow geometry on parameter uncertainties for underdamped slug tests in fractured rocks

Author:
A. Dausse; N. Guihéneuf; B.L. Parker
Source:
Journal of hydrology 2021 v.592 pp. 125567
ISSN:
0022-1694
Subject:
Bayesian theory; Markov chain; Monte Carlo method; aquifers; data collection; geometry; hydraulic conductivity; linear models; uncertainty
Abstract:
... these tests in fractured rocks can be challenging due to system complexity, which ultimately raises questions about the appropriate model for interpreting a given dataset. In order to obtain insights on this fundamental problem for slug test analyses in fractured rocks, a complete evaluation on three transient solutions for linear, radial and spherical flow configuration extended to include inertial ...
DOI:
10.1016/j.jhydrol.2020.125567