A new K-Ar illite dating application to constrain the timing of subduction in West Sarawak, Borneo

2021 ◽  
Author(s):  
Qi Zhao ◽  
Yi Yan ◽  
Satoshi Tonai ◽  
Naotaka Tomioka ◽  
Peter D. Clift ◽  
...  
Keyword(s):  
Fluid Flow ◽  
Subduction Zone ◽  
Vitrinite Reflectance ◽  
Accretion Process ◽  
Physical Chemical ◽  
Episodic Evolution ◽  
The Matrix ◽  
Chemical Attributes ◽  
Maximum Temperatures ◽  
Tectonic Mélange

The timing of subduction is a fundamental tectonic problem for tectonic models, yet there are few direct geological proxies for constraining it. However, the matrix of a tectonic mélange formed in a subduction-accretion setting archives the physical/chemical attributes at the time of deformation during the subduction-accretion process. Thus, the deformation age of the matrix offers the possibility to directly constrain the period of the subduction-accretion process. Here we date the Lubok Antu tectonic mélange and the overlying Lupar Formation in West Sarawak, Borneo by K-Ar analysis of illite. The ages of authigenic illite cluster around 60 Ma and 36 Ma. The maximum temperatures calculated by vitrinite reflectance values suggest that our dating results were not affected by external heating. Thus, the ages of authigenic illite represent the deformation age of the mélange matrix and the timing of the Rajang Unconformity, indicating that the subduction in Sarawak could have continued until ca. 60 Ma and the thermal and/or fluid flow events triggered by a major uplift of the Rajang Group occurred at ca. 36 Ma. Furthermore, this study highlights the potential of using the tectonic mélange to extract the timeframe of subduction zone episodic evolution directly.

Hydrogeology and Mechanics of Subduction Zone Forearcs: Fluid Flow and Pore Pressure

2011 ◽  
Vol 39 (1) ◽  
pp. 157-186 ◽  
Author(s):  
Demian M. Saffer ◽  
Harold J. Tobin
Keyword(s):  
Fluid Flow ◽  
Pore Pressure ◽  
Subduction Zone

Effect of Different Processing on Properties of Silica Sand

2010 ◽  
Vol 139-141 ◽  
pp. 528-531
Author(s):  
Qing Zhou Sun ◽  
Rong Fu Xu ◽  
Zhong Kui Zhao ◽  
Pu Qing Zhang ◽  
Wei Liu
Keyword(s):  
Grain Size ◽  
Tensile Strength ◽  
Size Distribution ◽  
Grain Size Distribution ◽  
Downward Trend ◽  
Silica Sand ◽  
Test Results ◽  
Molding Sand ◽  
Physical Chemical ◽  
Chemical Attributes

This paper will cover some processing routes along with grading and physical/chemical attributes of silica sand. The silica sand in this experiment was divided into four lots, and each of them was processed by the methods of calcining, scrubbing, mulling or rubbing respectively. The test results show that the sand grains which processed by different processing methods are irregular, the acid demand value of sand is lower than that of the base sand, and the grain size distribution of sand is similar to that of the base sand. However, the SiO2 content of processed sand is increased, the impurities content has a downward trend. Compared with the base sand, it can be found that the tensile strength value of molding sand prepared using the processed sands is higher and the bench life is almost no change.

Low-Salinity Chase Waterfloods Improve Performance of Cr(III)-Acetate Hydrolyzed Polyacrylamide Gel in Fractured Cores

2015 ◽  
Vol 19 (02) ◽  
pp. 331-339 ◽  
Author(s):  
Bergit Brattekås ◽  
Arne Graue ◽  
Randall S. Seright
Keyword(s):  
Fluid Flow ◽  
Water Phase ◽  
Polymer Gel ◽  
Low Salinity ◽  
Gel Swelling ◽  
The Matrix ◽  
Rupture Pressure ◽  
Salinity Water ◽  
Hydrolyzed Polyacrylamide ◽  
Blocking Capacity

Summary Polymer gels are frequently applied for conformance improvement in fractured reservoirs, where fluid channeling through fractures limits the success of waterflooding. Placement of polymer gel in fractures reduces fracture conductivity, thus increasing pressure gradients across matrix blocks during chase floods. A gel-filled fracture is reopened to fluid flow if the injection pressure during chase floods exceeds the gel-rupture pressure; thus, channeling through the fractures resumes. The success of a polymer-gel treatment, therefore, depends on the rupture pressure. Salinity differences between the gel network and surrounding water phase are known causes of gel swelling (e.g., observed in recent work on preformed particle gels). Gel swelling and its effect on fluid flow have, however, been less studied in conjunction with conventional polymer gels. By use of corefloods, this work demonstrates that low-salinity water can swell conventional Cr(III)-acetate hydrolyzed polyacrylamide (HPAM) gels, thereby significantly improving gel-blocking performance after gel rupture. Formed polymer gel was placed in fractured core plugs, and chase waterfloods were performed using four different brine compositions, of which three were low-salinity brines. The fluid flow rates through the matrix and differential pressures across the matrix and fracture were measured and shown to increase with decreasing salinity in the injected water phase. In some cores, the fractures were reblocked during low-salinity waterfloods, and gel-blocking capacity was increased above the initial level. Low-salinity water subsequently flooded the matrix during chase floods, which provided additional benefits to the waterflood. The improved blocking capacity of the gel was caused by a difference in salinity between the gel and injected water phase, which induced gel swelling. The results were reproducible through several experiments, and stable for long periods of time in both sandstone and carbonate outcrop core materials. Combining polymer gel placement in fractures with low-salinity chase floods is a promising approach in integrated enhanced oil recovery (IEOR).

Paleomagnetic and geochemical evidence for a pre-Triassic age for the Lower Amaranth Member of the Williston Basin of Manitoba (Canada)

2009 ◽  
Vol 46 (11) ◽  
pp. 855-873 ◽  
Author(s):  
Erika Szabó ◽  
Maria T. Cioppa ◽  
Ihsan S. Al-Aasm
Keyword(s):  
Fluid Flow ◽  
Oxygen Isotope ◽  
Carbon Isotope ◽  
Carbon Isotopes ◽  
Geochemical Data ◽  
Williston Basin ◽  
Oxygen And Carbon Isotopes ◽  
Oxygen And Carbon Isotope ◽  
The Matrix ◽  
Expected Values

Paleomagnetic and geochemical data obtained from six wells in southwestern Manitoba indicate that the Lower Amaranth redbeds were deposited earlier than Jurassic or Triassic, the most commonly cited depositional ages for this formation in the Williston Basin. The magnetization is carried primarily by detrital specular and pigmentary hematite and occasionally magnetite. Inclination-only analysis of paleomagnetic data (83 specimens from 60 plugs) indicates two possible depositional magnetization ages: Devonian–Pennsylvanian (D, found in very few samples) or Carboniferous to Permian, as suggested by the inclination and the polarity of the most predominant magnetization (B). An isolated magnetization (C) could be a mid-Jurassic to Neogene localized fluid flow remagnetization event. The oxygen and carbon isotope values of dolomite (–6.45‰ to 0.30‰ Vienna PeeDee Belemnite (VPDB) δ18O, –1.57‰ to 5.44‰ VPDB δ13C; n = 18) indicate that dolomitization could have occurred anytime between Carboniferous and Jurassic. However, the distribution of these values is a function of the three types of dolomite present in the Lower Amaranth strata: detrital, cement, and matrix replacive and reflects both the primary values and diagenetic overprints. Detrital and cement dolomite show depleted values in both oxygen and carbon isotopes, most likely inherited from the original values of the detrital dolomite, with superimposed effects of recrystallization. The matrix replacive dolomite has no detrital content, and its oxygen isotope values are similar to the expected values for primary or early diagenetic dolomite from Carboniferous to Jurassic times. Mixtures of detrital and replacive matrix dolomite give intermediate oxygen and carbon isotope values.

scholarly journals Influence of fertilizer and hydrogel on physical-chemical attributes of substrate for seedling production

2019 ◽  
Vol 35 (5) ◽  
Author(s):  
Glauce Taís de Oliveira Sousa Azevedo ◽  
Anderson Marcos de Souza ◽  
Gileno Brito de Azevedo ◽  
Paulo Eduardo Teodoro ◽  
José Raimundo Luduvico de Sousa
Keyword(s):  
Water Retention ◽  
Water Retention Capacity ◽  
Forest Nursery ◽  
Retention Capacity ◽  
Physical Chemical ◽  
Physical Attributes ◽  
Chemical Attributes ◽  
Physical And Chemical ◽  
Different Levels ◽  
Different Doses

The incorporation of the hydrogel into the substrate used in the forest nursery promotes improvements in its physical-chemical attributes. However, several factors influence the hydrogel efficiency, such as the increase of salts, promoted by fertilizer of the substrate. Therefore, this study aimed to evaluate the effects of the incorporation of fertilizer levels and hydrogel doses on the physical-chemical attributes of a substrate to produce forest seedlings. Different levels of basic fertilizer commonly used in the nursery (100%, 50% and 0%) and different doses of the hydrogel (0, 1, 2 and 3 g L-1) were incorporated into the substrate Tropstrato Florestal®, consisting of 12 treatments in a 3 x 4 factorial scheme. A sample of the substrate in each treatment was sent for analysis of its physical and chemical attributes. To evaluate the effect of the treatments on the physical-chemical attributes of the substrate, was used the multivariate principal components analyses. The levels of fertilizer and hydrogel doses were correlated with the attributes of the substrates obtained in each treatment. The incorporation of different fertilizer levels and hydrogel doses to the substrate modified their chemical and physical attributes. Fertilizers have influenced mainly the chemical attributes of the substrate, whereas hydrogels have influenced the physical attributes, mainly those related to water retention capacity and availability.

scholarly journals Hierarchical modelling for recycling-oriented classification of shredded spent flat monitor products based on HyperSpectral Imaging

Detritus ◽  
2020 ◽  
pp. 122-130
Author(s):  
Giuseppe Bonifazi ◽  
Riccardo Gasbarrone ◽  
Roberta Palmieri ◽  
Silvia Serranti
Keyword(s):  
Hyperspectral Imaging ◽  
High Performance ◽  
Near Infrared ◽  
Low Cost ◽  
Volume Growth ◽  
Growth Trend ◽  
Hierarchical Modelling ◽  
Physical Chemical ◽  
Chemical Attributes ◽  
Set Up

The number of flat monitors from televisions, notebooks and tablets has increased dramatically in recent years, thus resulting in a corresponding rise in Waste from Electrical and Electronic Equipment (WEEE). This fact is linked to the production of new high-performance electronic devices. Taking into account a future volume growth trend of WEEE, the implementation of adequate recycling architectures embedding recognition/classification logics to handle the collected WEEE physical-chemical attributes, is thus necessary. These integrated hardware and software architectures should be efficient, reliable, low cost, and capable of performing detection/control actions to assess: i) WEEE composition and ii) physical-chemical attributes of the resulting recovered flow streams. This information is fundamental in setting up and implementing appropriate recycling actions. In this study, a hierarchical classification modelling approach, based on Near InfraRed (NIR) - Hyperspectral Imaging (HSI), was carried out. More in detail, a 3-step hierarchical modelling procedure was designed, implemented and set up in order to recognize different materials present in a specific WEEE stream: End-of-Life (EoL) shredded monitors and flat screens. By adopting the proposed approach, different categories are correctly recognized. The results obtained showed how the proposed approach not only allows the set up of a “one shot” quality control system, but also contributes towards improving the sorting process.

scholarly journals Geochemical and Isotopic Evidence for Fluid Flow in the Western Nankai Subduction Zone, Japan

1993 ◽  
Author(s):  
M. Kastner ◽  
H. Elderfield ◽  
W.J. Jenkins ◽  
J.M. Gieskes ◽  
T. Gamo
Keyword(s):  
Fluid Flow ◽  
Subduction Zone ◽  
Isotopic Evidence ◽  
Nankai Subduction Zone
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