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1. A phenomenological modelling of rocks based on the influence of damage initiation

Author:
Zhao, Heng; Zhou, Shuai; Zhang, Ling
Source:
Environmental earth sciences 2019 v.78 no.5 pp. 143
ISSN:
1866-6280
Subject:
rocks,   etc   ; models; prediction; probability;     Show all 4 Subjects
Abstract:
... It is recognized that the stress-induced damage impacts the progressive failure behavior of rocks. A phenomenological model for the compressive failure of rocks is thus presented in this study. The model addresses the progressive growth of damage that leads to the strength weakening on a macroscopic scale. Considering dramatic difference between uniaxial compression and tension strengths for rocks ...
DOI:
10.1007/s12665-019-8172-9

2. Uppermost Permian to Lower Triassic conodont successions from the Enshi area, western Hubei Province, South China

Author:
Lyu, Zhengyi; Orchard, Michael J.; Chen, Zhong-Qiang; Wang, Xiangdong; Zhao, Laishi; Han, Chen
Source:
Palaeogeography, palaeoclimatology, palaeoecology 2019 v.519 pp. 49-64
ISSN:
0031-0182
Subject:
carbonate rocks,   etc   ; fossils; paleoecology; China;     Show all 4 Subjects
Abstract:
... We present recent study results of the Lower Triassic conodont succession from the Ganxi and Jianshi areas of Enshi city, western Hubei Province, South China, which were situated on a carbonate ramp at the northeastern margin of the Upper Yangtze Platform. Therein, the uppermost Permian to Lower Triassic succession is well exposed and yielded abundant conodonts. A total of nine conodont zones are ...
DOI:
10.1016/j.palaeo.2017.08.015

3. The Role of Fault‐Zone Architectural Elements on Pore Pressure Propagation and Induced Seismicity

Author:
Ortiz, John P.; Person, Mark A.; Mozley, Peter S.; Evans, James P.; Bilek, Susan L.
Source:
Ground water 2019 v.57 no.3 pp. 465-478
ISSN:
0017-467X
Subject:
rocks,   etc   ; Permian period; basins; groundwater; models; permeability;     Show all 6 Subjects
Abstract:
... We used hydrogeologic models to assess how fault‐zone properties promote or inhibit the downward propagation of fluid overpressures from a basal reservoir injection well (150 m from fault zone, Q = 5000 m³/day) into the underlying crystalline basement rocks. We varied the permeability of the fault‐zone architectural components and a crystalline basement weathered layer as part of a numerical sensi ...
DOI:
10.1111/gwat.12818

4. Multi-stage structural and kinematic analysis of a retrogressive rock slope instability complex (Preonzo, Switzerland)

Author:
Gschwind, Sophie; Loew, Simon; Wolter, Andrea
Source:
Engineering geology 2019 v.252 pp. 27-42
ISSN:
0013-7952
Subject:
rocks,   etc   ; data collection; deformation; landslides; tectonics; Switzerland;     Show all 6 Subjects
Abstract:
... Large catastrophic rock slope failures are difficult to predict because the underlying mechanisms causing slope accelerations are difficult to study under in-situ conditions. For slope failures with compound basal rupture planes, not only fracture propagation and slip in the basal rupture surface, but also within the landslide body control the displacement evolution and time-to-failure. The Preonz ...
DOI:
10.1016/j.enggeo.2019.02.018

5. The importance of a weak mid-lithospheric layer on the evolution of the cratonic lithosphere

Author:
Wang, Zhensheng; Kusky, Timothy M.
Source:
Earth-science reviews 2019 v.190 pp. 557-569
ISSN:
0012-8252
Subject:
rocks,   etc   ; Precambrian time; delamination; geophysics; models; viscosity;     Show all 6 Subjects
Abstract:
... Seismically detectable discontinuities at mid-depths of some cratonic lithospheric mantle define mid-lithosphere discontinuities (MLD), demonstrating that the lithospheric mantle is layered. The genesis and strength of the MLD are still in debate, most proposed models suggest the MLD is likely not weaker than the normal lithosphere, whereas other proposed models suggest that some metasomatised MLD ...
DOI:
10.1016/j.earscirev.2019.02.010

6. Fracture evolution in artificial bedded rocks containing a structural flaw under uniaxial compression

Author:
Wang, Ding-Jian; Tang, Huiming; Elsworth, Derek; Wang, Chaoyi
Source:
Engineering geology 2019 v.250 pp. 130-141
ISSN:
0013-7952
Subject:
rocks,   etc   ; cracking; engineering; isotropy; prediction; shear stress;     Show all 6 Subjects
Abstract:
... The Observation and prediction of crack propagation are important in understanding rock behavior in engineering practice. Previous studies have focused on homogeneous and isotropic rocks, but the influence of bedding planes on rock fracture is sparingly documented. In this study, we investigate the fracturing response in uniaxial compression of artificial bedded rocks containing variable-inclinati ...
DOI:
10.1016/j.enggeo.2019.01.011

7. Review and assessment of In-situ rock stress in Hong Kong for territory-wide geological domains and depth profiling

Author:
Lai, Cheuk Yiu; Wong, Louis Ngai Yuen; Wallace, Mark
Source:
Engineering geology 2019 v.248 pp. 267-282
ISSN:
0013-7952
Subject:
rocks,   etc   ; hydraulic fracturing; test reports; China;     Show all 4 Subjects
Abstract:
... Hydraulic fracturing is a favorably used technique to measure in-situ rock stress orientation and magnitude for the design of underground excavations. In Hong Kong, studies prior to 2000 revealed a general WNW-ESE maximum horizontal stress orientation and established stress ratio depth profile. However, there is a paucity of geological assessment on the in-situ stress. By examining 380 no. of in-s ...
DOI:
10.1016/j.enggeo.2018.11.008

8. Otters Lutra lutra Switch to Costly Territorial Advertising when Occurrence Frequency Increases

Author:
Kosmowska, Anna; Romanowski, Jerzy
Source:
Mammal study 2019 v.44 no.1
ISSN:
1348-6160
Subject:
rocks,   etc   ; Lutra lutra; advertising; feces; grasses;     Show all 5 Subjects
Abstract:
... Otters (Lutra lutra) mark territories by depositing feces on prominent spots, like rocks or large tussocks of grass. However, sometimes they defecate on intentionally mounded heaps made of mud and/or plant material. We show that in sites occupied by otters the frequency of heap-making significantly increases with the frequency of otters occurrence and is independent of the availability of naturall ...
DOI:
10.3106/ms2017-0083

9. Transport of oxygen into granitic rocks: Role of physical and mineralogical heterogeneity

Author:
Trinchero, Paolo; Sidborn, Magnus; Puigdomenech, Ignasi; Svensson, Urban; Ebrahimi, Hedieh; Molinero, Jorge; Gylling, Björn; Bosbach, Dirk; Deissmann, Guido
Source:
Journal of contaminant hydrology 2019 v.220 pp. 108-118
ISSN:
0169-7722
Subject:
rocks,   etc   ; biotite; oxygen; radionuclides; snowmelt; surface area;     Show all 6 Subjects
Abstract:
... The rock matrix of granites is expected to be an important buffer against the dispersion of contaminants, e.g. radionuclides, and against the ingress of oxygenated glacial meltwater. The influence of matrix heterogeneity on O2 diffusive transport is assessed here by means of numerical experiments based on a micro-Discrete Fracture Network (micro-DFN) representation of the diffusion-available pore ...
DOI:
10.1016/j.jconhyd.2018.12.001

10. Radon concentrations in the community groundwater system of South Korea

Author:
Cho, Byong Wook; Kim, Hyeon Koo; Kim, Moon Su; Hwang, Jae Hong; Yoon, Uk; Cho, Soo Young; Choo, Chang Oh
Source:
Environmental monitoring and assessment 2019 v.191 no.3 pp. 189
ISSN:
0167-6369
Subject:
sedimentary rocks; volcanic rocks,   etc   ; World Health Organization; granite; groundwater; isotopes; radon; rural areas; wells; South Korea;     Show all 10 Subjects
Abstract:
... Groundwater samples were collected from 3818 wells used for the community groundwater system (CGS) in the remote rural areas of South Korea and analyzed to determine radon concentrations. Radon concentrations varied with rock type, ranging from 0.1 to 2393.5 Bq/L with an average of 86.6 Bq/L and a median of 46.4 Bq/L. Among 10 geological units, the median CGS radon concentration was highest (59.6– ...
DOI:
10.1007/s10661-019-7301-y

11. The geology of North Korea: An overview

Author:
Zhai, Mingguo; Zhang, Xiao-Hui; Zhang, Yan-Bin; Wu, Fu-Yuan; Peng, Peng; Li, Qiu-Li; Li, Zhong; Guo, Jinghui; Li, Tie-Sheng; Zhao, Lei; Zhou, Li-Gang; Zhu, Xiyan
Source:
Earth-science reviews 2019 v.194 pp. 57-96
ISSN:
0012-8252
Subject:
igneous rocks; metamorphic rocks; sedimentary rocks,   etc   ; Cretaceous period; Jurassic period; Neoproterozoic era; Paleoproterozoic era; Paleozoic era; Triassic period; basins; tectonics; China; North Korea; South Korea;     Show all 14 Subjects
Abstract:
... The Korean Peninsula (KP) occupies a junction area of three big tectonic domains that are the Paleo-Central Asian Orogenic Belt, Paleo-Tethyan Orogenic Belt and the Western Pacific Orogenic Belt. Therefore the KP is a key area to understand the Northeast Asian and even global geotectonic evolution. In terms of geological unit division, the KP has long been thought to be closely tied with the mainl ...
DOI:
10.1016/j.earscirev.2019.04.025

12. Semi-arid soils from a topolithosequence at James Ross Island, Weddell Sea region, Antarctica: Chemistry, mineralogy, genesis and classification

Author:
Daher, Mayara; Schaefer, Carlos E.G.R.; Fernandes Filho, Elpídio Inácio; Francelino, Márcio Rocha; Senra, Eduardo Osório
Source:
Geomorphology 2019 v.327 pp. 351-364
ISSN:
0169-555X
Subject:
metamorphic rocks; sedimentary rocks; volcanic rocks,   etc   ; Cryosols; Gelisols; acidity; clay fraction; climate; desert pavement; kaolinite; landscapes; semiarid soils; soil formation; soil pH; terraces; topography; vegetation; Antarctic region; Antarctica;     Show all 19 Subjects
Abstract:
... Climate and parent material have a significant impact on the development of Antarctic soils, and areas dominated by basaltic-andesitic volcanic rocks, sedimentary rocks, and metamorphic rocks have been widely studied. James Ross Island, located in the semi-arid transition between East Antarctic Peninsula/Weddell Sea sector, receives both continental and maritime climatic influences, resulting in d ...
DOI:
10.1016/j.geomorph.2018.11.003

13. Reply to comment on “validity of using large-density asymptotics for studying reaction-infiltration instability in fluid-saturated rocks”

Author:
Zhao, Chongbin; Hobbs, B.E.; Ord, A.
Source:
Journal of hydrology 2018 v.564 pp. 928-929
ISSN:
0022-1694
Subject:
rocks,   etc   ; differential equation; hydrology;     Show all 3 Subjects
Abstract:
... In this reply we further demonstrate and confirm that the main conclusion (namely, that the asymptotic limit of the acid dissolution capacity can lead to sharp dissolution fronts) in our recent publication in this journal is correct and valid. The basis of the incorrect critique in the comment is whether or not a physically-consistent velocity scale should be used in deriving the dimensionless par ...
DOI:
10.1016/j.jhydrol.2018.07.059

14. In situ observation and evaluation of zonal disintegration affected by existing fractures in deep hard rock tunneling

Author:
Feng, Xia-Ting; Guo, Hao-Sen; Yang, Cheng-Xiang; Li, Shao-Jun
Source:
Engineering geology 2018 v.242 pp. 1-11
ISSN:
0013-7952
Subject:
rocks,   etc   ; engineering; China;     Show all 3 Subjects
Abstract:
... Zonal disintegration refers to the phenomenon whereby fractured zones and intact zones appear alternately in surrounding hard rocks under high stress conditions. In this study, zonal disintegration within hard surrounding rocks of deep tunnels at the China Jinping Underground Laboratory Phase II (CJPL-II) was observed by using a digital borehole televiewer in pre-drilled boreholes. The results rev ...
DOI:
10.1016/j.enggeo.2018.05.019

15. The control effect of surrounding rock with different combinations of the bolt anchoring lengths and pre-tightening forces in underground engineering

Author:
Wang, Q.; Pan, R.; Li, S. C.; Wang, H. T.; Jiang, B.
Source:
Environmental earth sciences 2018 v.77 no.13 pp. 501
ISSN:
1866-6280
Subject:
rocks,   etc   ; bolts; mechanical properties;     Show all 3 Subjects
Abstract:
... The anchoring length and the pre-tightening force are the two main factors influencing the control effect of surrounding rock in bolt support. To study the influences, a theoretical analysis is made on the stress distribution law of the surrounding rock with different anchoring lengths and pre-tightening forces; a high pre-tightening force quantitative exerting device for high strength bolts is de ...
DOI:
10.1007/s12665-018-7682-1

16. A program to calculate pulse transmission responses through transversely isotropic media

Author:
Li, Wei; Schmitt, Douglas R.; Zou, Changchun; Chen, Xiwei
Source:
Computers & geosciences 2018 v.114 pp. 59-72
ISSN:
0098-3004
Subject:
rocks,   etc   ; computers; models; ultrasonics;     Show all 4 Subjects
Abstract:
... We provide a program (AOTI2D) to model responses of ultrasonic pulse transmission measurements through arbitrarily oriented transversely isotropic rocks. The program is built with the distributed point source method that treats the transducers as a series of point sources. The response of each point source is calculated according to the ray-tracing theory of elastic plane waves. The program could ...
DOI:
10.1016/j.cageo.2018.02.002

17. Rock avalanche mobility: The role of path material

Author:
Aaron, Jordan; McDougall, Scott
Source:
Engineering geology 2019 v.257 pp. 105126
ISSN:
0013-7952
Subject:
rocks,   etc   ; avalanches; case studies; infrastructure; landscapes; models; prediction; topography;     Show all 8 Subjects
Abstract:
... Rock avalanches are high velocity flows of fragmented rock that can dramatically alter landscapes, and impact people and infrastructure far from their source. These catastrophic events have been studied for over a century, however, a consensus regarding the mechanism(s) that govern their motion has yet to emerge. This work details the results of the back-analysis of 45 rock avalanche case historie ...
DOI:
10.1016/j.enggeo.2019.05.003

18. Recent progress of geophysical and geological studies of Mt. Fuji Volcano, Japan

Author:
Aoki, Yosuke; Tsunematsu, Kae; Yoshimoto, Mitsuhiro
Source:
Earth-science reviews 2019 v.194 pp. 264-282
ISSN:
0012-8252
Subject:
rocks,   etc   ; geophysics; people; volcanoes; Eurasia; Japan; Philippine Sea;     Show all 7 Subjects
Abstract:
... Mt. Fuji, located in central Japan near the triple junction of the Philippine Sea, Eurasia (or Amurian), and North American (or Okhotsk) plates, is one of the arc volcanoes associated with the subduction of the Pacific plate. Mt. Fuji has unique features including an average eruption rate in the last 100,000 years of 4–6 km3/ka, which is much higher than that of other volcanoes along the same arc ...
DOI:
10.1016/j.earscirev.2019.05.003

19. Early Cretaceous tectonic rejuvenation of an Early Jurassic margin in the Central Apennines: The “Mt. Cosce Breccia”

Author:
Cipriani, Angelo; Bottini, Cinzia
Source:
Sedimentary geology 2019 v.387 pp. 57-74
ISSN:
0037-0738
Subject:
rocks,   etc   ; Early Cretaceous epoch; Hettangian age; carbonates; cartography; microfossils; tectonics;     Show all 7 Subjects
Abstract:
... Evidence for an extension-dominated tectonic phase in the late Early Cretaceous has been identified for the first time at Mt. Cosce in the Narni Ridge (60 km N of Rome, Central Apennines) as a result of geological mapping. There, the Umbria-Marche-Sabina pelagic succession overlies shallow-water carbonates (Calcare Massiccio Formation, Hettangian). The Mt. Cosce area represents a Jurassic pelagic ...
DOI:
10.1016/j.sedgeo.2019.03.002

20. Theoretical development of a natural soil-landscape classification system: An interdisciplinary approach

Author:
Nikiforova, Aleksandra A.; Bastian, Olaf; Fleis, Maria E.; Nyrtsov, Maxim V.; Khropov, Aleksandr G.
Source:
Catena 2019 v.177 pp. 238-245
ISSN:
0341-8162
Subject:
rocks,   etc   ; air; geographic information systems; landscapes; soil; soil classification; Russia;     Show all 7 Subjects
Abstract:
... It is proposed to use the General Systems Theory (open system) approach and the General Theory of Classification to make progress in soil classification. It is shown that on this basis it is possible to develop the theoretical basis for a natural soil-landscape classification system, which could serve as a universal one. The main difference between this classification system and existing ones is i ...
DOI:
10.1016/j.catena.2019.02.026