Cracking behavior and mechanism of sandstone containing a ...

2016-11-4 · The sandstones were processed into samples with dimensions of 100 × 100 × 50 mm ().The two end faces that bear the static loads were carefully abraded, and their parallelism was not less than 0.02 mm.A flat-bottomed hole of 8 mm in diameter and 45 mm in depth was drilled along the vertical direction for the application of impact loads. ...

Grain-scale failure mechanism of porous sandstone: An ...

2020-8-1 · The microscale failure mechanism of sandstone during the Brazilian tensile test was thoroughly analysed with the numerical result and the CT-scan data after the test. The main findings include: 1) As observed in both the numerical and experimental test, the fracture paths in the specimens during Brazilian tensile test were dominated by the ...

(PDF) Tight sandstone gas accumulation mechanism and ...

2015-10-19 · Tight sandstone gas serves as an important unconventional hydrocarbon resource, and outstanding results have been obtained through its discovery both in …

Grain-scale failure mechanism of porous sandstone: An ...

The microscale failure mechanism of sandstone during the Brazilian test was thoroughly analysed using the numerical results together with the post failure CT-scan test data. The build-up of compressive and tensile stress chains, micro-crack nucleation, local relaxation, chain switching and final crack-path development exploiting pores was ...

Predicting reservoir drive mechanism

2016-2-24 · Predicting drive type. Reservoir analysis includes making cross sections, structural maps, and isopach maps.Analyzing nearby producing fields yields the best set of inferential data. This includes (1) making plots of historical oil, gas, condensate, and water production and pressure decline and (2) making cumulative production maps.

A study on thermal damage mechanism of sandstone based …

2021-6-3 · Kinetic mechanism analysis of sandstone pyrolysis. The pyrolysis of sandstone is controlled by many factors, among which the pyrolysis environment and mineral composition are very important. Comparing with Figs. 9 and 10, the E and A of sandstone pyrolysis in air are greater than those in argon. When sandstone is pyrolyzed in argon atmosphere ...

Failure process and mechanism of sandstone under combined ...

2018-1-18 · The process and mechanism of impact fractures in sandstone were investigated under equal biaxial static compression. The cracking process was captured by a high-speed video camera. The results indicate that the main crack propagates along the …

Breakage Mechanism of Layered Sandstone Penetrated by TBM ...

2021-3-3 · In this paper, the breakage mechanism of layered sandstone subjected to the TBM disc cutter was investigated. A series of typical layered sandstone specimens were prepared for true triaxial compression tests in the laboratory to simulate the disc cutter action at the tunnel face, and an acoustic emission (AE) system was used to monitor the breaking process during the penetration tests.

Study on microstructure mechanism of sandstone based …

S TUDY ON MICROSTRUCTURE MECHANISM OF SANDSTONE BASED ON COMPLEX NETWORK THEORY. L IU G UANNAN, Y E D AYU, L IANG X IN, Z HU X IAOQIAN, G AO F ENG 28 JOURNAL OF M EASUREMENTS IN E NGINEERING.M ARCH 2020, V OLUME 8, ISSUE 1 distribution with high average path length. As transition from rule network to random network, Fig. 1(c) shows the degree of …

(PDF) 📄 Seepage Mechanism of Tight Sandstone Reservoir ...

2021-4-21 · seepage mechanism of a tight sandstone reservoir as follows. Appl. Sci. 2021, 11, 3741 9 of 10 (1) The macroscopic starting pressure gradient is embodied in the microscopic por e

Progressive Failure and Fracture Mechanism of Sandstone ...

2020-9-30 · Hydraulic coupling often leads to progressive rock failure accidents. Mechanical tests were performed over a range of combined pore water pressure and confining pressure stress path conditions to study the progressive failure characteristics of sandstone under hydraulic-mechanical coupling and explore the crack initiation and pore water fracture mechanism.

Study on microstructure mechanism of sandstone based on ...

Study on microstructure mechanism of sandstone based on complex network theory. Abstract. Rock contains a large number of micro-pores, which are of different shapes and complex structures. The structure information of sandstones is extracted based on different porosities through X-ray CT (Computer Tomography) scanning, photo processing ...

Sand Production Mechanism and Changes of Rock …

2016-1-8 · The mechanism of rock failure includes mechanical failure and chemical failure. The chapter examines appraisal experiments of sand production on changing formation properties that combine the case of unconsolidated sandstone reservoirs in Bohai Bay. It reviews the mechanism of sand production from the standpoint of experiments.

Chapter 14

2015-11-4 · TIGHT GAS SANDSTONE RESERVOIRS, PART 1: OVERVIEW AND LITHOFACIES 14 Y. Zee Ma1, W.R. Moore1, E. Gomez1, W.J. Clark1, Y. Zhang2 Schlumberger, Denver, CO, USA1; University of Wyoming, Laramie, WY, USA2 14.1 INTRODUCTION AND OVERVIEW Although shale gas plays have been in the spotlight recently, natural gas in tight sandstones is actually

Technical Note Bearing behavior and failure mechanism …

2015-5-21 · cemented sandstone. The model tests used artificial rocks, which reasonably simulate the natural poorly cemented sandstone. The results reveal the load-bearing behavior and failure mechanism of poorly cemented sandstone, with both plasticity and brittle characteristics, is distinct from the cases on hard rock or soil. Consequently, the bearing

Formation damage mechanism of a sandstone reservoir …

2021-1-2 · Formation damage caused by well drilling, completion, oil testing, oil recovery, and stimulation seriously affects oil and gas production, the evaluation of which plays an important role in the process of oilfield development. Thus, it is necessary to study formation damage mechanism from micro scale. In this study, two sets of displacement experiments were conducted using two sandstone ...

PERF Researchers Determine Key Mechanism Driving …

2021-6-14 · sandstone reservoir prior to hydraulic fracturing. SOLUTION Conduct sandstone acidizing experiments with different blends at downhole conditions, including the operator''s first hydrofluoric acid (HF) studies, for extensive digital analysis. RESULTS Revealed that use of HF is not necessary because the mechanism for permeability

Mechanism of formation of wiggly compaction bands in ...

2015-11-17 · The host rock of compaction bands has high porosity [Sternlof et al., 2005; Liu et al., 2015], and the loss of porosity is a primary characteristic of CBs [Sternlof et al., 2005].For a rock that exhibits a significant component of compactive yielding during deformation, such as the porous sandstone, there is a cap on graphs, for example, of deviatoric stress versus effective mean stress, that ...

Study on weathering mechanism of sandstone statues in ...

Downloadable (with restrictions)! To understand the weathering mechanism of sandstone statues in Southwest China, the sandstone of Niche of Sakyamuni Entering Nirvana at Dazu Rock Carvings was sampled. The three experiments were set up, including dry–wet cycle, freeze–thaw cycle and acid rain cycle. In this study, the mass, surface hardness, P-wave velocity were applied to explore the ...

Mechanism of formation of wiggly compaction bands in ...

1 Introduction. Compaction bands (CBs) in porous sandstone have received increasing attention recently [Eichhubl et al., 2010; Fossen et al., 2011; Cecinato and Gajo, 2014].They are characterized by volume loss, some microfracturing, very little grain crushing, and lack of macroscopic shear offset across their plane [Sternlof et al., 2005].They are relatively impermeable and can act as ...

Weathering mechanism of arenite sandstone with sparse ...

Abstract We conducted a multifaceted analysis of the weathering zones of arenite, containing a minute amount of calcite cement, based on mineralogical, chemical, and physical properties. The survey targeted sandstone with mudstone interbeds belonging to the Cretaceous Izumi Group. The survey revealed that the weathering mechanism is a chain reaction; the most important process is the pore ...

(PDF) Mechanism of Permeability Evolution for Reservoir ...

the sandstone without mud (Figur e (a)); however, the quartz a n df e l d s p a ri n s i d et h es a n d s t o n ew i t hm u da r el e s so b v i o u s b e c a u s eo fm o r ec l a yw i t hm u dc ...

Dynamic response and meso-deterioration mechanism of …

And this paper use the test system of Split Hopkinson Pressure Bar (SHPB) to survey the impact test action of different porosity red sandstone in different coupling medium in order to obtained the ...

Microscopic mechanism of sandstone hydration in Yungang ...

3.4.2 Microscopic mechanism of sandstone hydration. Now we provide an explanation of the sandstone hydration. As the water molecules permeate into the crystal of minerals and bring out the cations to generate new minerals, changes in the sandstone structure may occur both in the macroscopic scale and in the microscopic scale.

Microscopic mechanism of sandstone hydration in Yungang ...

The macroscopic engineering properties of sandstone are dominated primarily by mineral features in a microscopic scale. This study will investigate the microscopic physical and mechanical properties of the main minerals (quartz, K-feldspar, Na-feldspar and kaolinite) in Yungang Grottoes sandstone, using the molecular mechanics and the molecular dynamics simulations.

The mineralization mechanism and model of sandstone type ...

The mineralization mechanism and model of sandstone type uranium deposit in Yili basin. [en] Based on the study of regional tectonics, stratum, lithological character, facies paleoleography, uranium mineralization character and its controlling factors, the authors discuss the mineralization mechanism and model of interlayer oxidation zone ...

Alcohol Abuse as a Coping Mechanism

Many people use alcohol as a coping mechanism – in fact in our culture we find reference to this everywhere: TV and movies are full of characters drinking to take the sting out of a break-up, downing shots in order to feel comfortable at a party, or having a glass of wine after a stressful day.

Study of Porous Flow Mechanism for Low-Permeability ...

This study researched the following: microscopic mechanism of the water-gas flow in low-permeability sandstone through the core experiment, measurement method for water saturation with nuclear magnetic resonance (NMR) technology, calculation method for mobile water saturation measurement, effect of the crustal stress on permeability of the core ...

Mechanistic study of wettability alteration of oil-wet ...

2015-3-1 · The figure shows the schematic diagram of the wettability alteration mechanism of oil-wet sandstone surface by nonionic surfactant TX-100 and anionic surfactant POE(1). This figure could also help the readers to visualize the mechanism of wettability alteration of the oil-wet sandstone surface caused by TX-100 and POE(1).

A New Mechanism of Formation Damage in Sandstone …

2014-10-27 · Authigenic apatite, (Ca 5 (PO 4) 3 (OH, F, Cl) 2), is a cementing material in fluvial sandstone formations. If apatite is present in the formation, it will cause precipitation during matrix acidizing. The objective of this paper is to discuss a new mechanism of formation damage caused by apatite during matrix acidizing.

Chemical Mechanism of Low Salinity Water Flooding i n ...

2011-12-4 · Chemical Mechanism of Low Salinity Water Flooding i n Sandstone Reservoirs ... sandstone reservoirs by performing a tertiary low saline waterflood. Due to the complexity of the crude oil-brine- ... Prior to use, the oils were centrifuged to remove any possible particles and water. Table 1 …