Microfracturing in the Upper Triassic Sichuan Basin tight-gas sandstones

Microfracturing in the Upper Triassic Sichuan Basin

tight-gas sandstones: Tectonic,overpressure,

and diagenetic origins

Lianbo Zeng

ABSTRACT

The western Sichuan Basin located at the front of the Long-men Mountain in the western Sichuan Province of China is a foreland basin formed in the Late Triassic.The Upper Triassic Xujiahe Formation in the basin is an ultralow-permeability and low-porosity tight-gas sandstone reservoir.Microfractures,such as intragranular microfractures,grain-edge microfractures,and transgranular microfractures,are abundant in the tight sand-stones.Microfractures improve storage and permeability and impact distribution of natural gas.Microfractures reflect tec-tonic,overpressure,and diagenetic https://www.wendangku.net/doc/2f16948626.html,ing quartz and calcite fluid inclusions and burial history,tectonic microfrac-tures were determined to be formed at the end of the Triassic, the end of the Cretaceous,and the end of the Neogene–early Pleistocene.Microfractures related to overpressure,being ten-sion microfractures,are commonly filled with bitumen and were formed at the middle to Late Cretaceous when the maximum pressure coefficients were1.6to2.1.In the middle to late Neo-gene,the pressure coefficient was reduced to less than1.3be-cause of fault activity and tectonic uplift in the southwestern Sichuan Basin,and these tension microfractures closed and were filled with calcite.The transition of stress state from compres-sion to tension by overpressure is the reason that tension micro-fractures were formed in the compression setting.Diagenetic fractures were formed at the end of the Late Triassic to Jurassic. Under intense compaction,grain-crushing crackle fractures in quartz and cleavage fractures in feldspar formed intragranular AUTHOR

Lianbo Zeng Key State Laboratory of Pe-troleum Resource and Prospecting in China Petroleum University,Changping,Beijing, 102249,China;lbzeng@https://www.wendangku.net/doc/2f16948626.html,

Lianbo Zeng is a professor of geology in the Key State Laboratory of Petroleum Resource and Prospecting at China Petroleum University. He received his M.S.degree from the China University of Geosciences and his Ph.D from the China Petroleum University.His interests include tectonic stress fields,natural fracture systems,and low-permeability reservoir characterization. ACKNOWLEDGEMENTS

The author thanks Li Yuegang,and Yang Yueming, the senior engineers at the Southwest Oil and Gas Field Branch,PetroChina Company Limited, for their constructive help.The author is par-ticularly grateful to the reviewers of this text, Catherine L.Hanks,William A.Hill,Ronald A. Nelson,Stuart D.Harker,and the anonymous reviewer,who provided excellent advice on the clarity of the text and figures.This study is financially supported by the Foundation of State Key Laboratory of Petroleum Resource and Prospecting,China University of Petroleum, Beijing(No.PRPJC2008-03,PRPDX2008-07). The AAPG Editor thanks the following reviewers for their work on this article:J.P.Brandenburg, Stuart D.Harker,and Ronald A.Nelson.

Copyright?2010.The American Association of Petroleum Geologists.All rights reserved. Manuscript received November25,2009;provisional acceptance February8,2010;revised manuscript received March15,2010;final acceptance June30,2010.

DOI:10.1306/06301009191EDITOR’S NOTE

Color versions of Figures1,3–6,and9–13can be seen in the online version of this article.

AAPG Bulletin,v.94,no.12(December2010),pp.1811–18251811

microfractures.Some transgranular microfractures caused by diagenesis are along the bedding plane and parallel to the directional mineral grains. INTRODUCTION

Fractures are important fluid-flow conduits in the subsurface and important repositories of oil and gas.Analysis of core samples can provide the most direct method to evaluate large fractures(macro-fractures)in the subsurface.However,cores pro-vide a volume of rock that is too small to charac-terize these macrofractures,which commonly have dimensions and spacing that are larger than the diameter of core.Kranz(1983)reviewed the oc-currence of microfractures in rocks.In contrast to large fractures,microfractures are commonly more abundant in the same volume of rock(Ortega and Marrett,2000;Ortega et al.,2006)and can pro-vide information on the associated macroscopic fractures.Microfractures can also be used as paleo-stress indicators,strain gauges,and markers of de-formation timing(Laubach,1989).In sedimentary rocks,description of microfracture populations that have been fossilized by authigenic cements in-volves high-magnification measurement(Onasch, 1990;Laubach,1997;Ortega and Marrett,2000; Wilson et al.,2003).Ortega and Marrett(2000)re-ported prediction of macrofracture properties using microfracture information and found that system-atic analysis of abundant microfractures in small pieces of rock could overcome the severe limita-tions of acquiring subsurface macrofracture data. Gomez and Laubach(2006)reported rapid digi-tal imaging and quantification methods vital for analysis of microfracture populations.This ap-proach can provide key evidence for numbers of sets,strike,crosscutting relations,strain,the volume of microfracture-sequestered cement,and meaning-ful data on microfracture population size and spac-ing patterns that would not be evident otherwise.

A microfracture is a fracture that can only be detected with magnification(Laubach,1997;Zeng and Li,2009).Microfractures are well developed in the Upper Triassic Xujiahe Formation in the western Sichuan Basin,China.The Upper Triassic Xujiahe Formation is an important natural gas play in the western Sichuan Basin.At present,commer-cial gas flows have been found in several structures, including Qiongxi,Pingluoba,and Baimamiao.The formation has great potential as a natural gas re-source,and it is becoming a significant exploration target in the Sichuan Basin(Yang,2003;Yue,2004). Recent research indicates that microfractures in these rocks provide important storage space and in-crease the permeability of these tight sandstones. Microfractures are likely a key factor for controlling natural gas accumulation and high production rates (Wu et al.,2002;Tang et al.,2004).Therefore,un-derstanding the formation and distribution of micro-fractures has great significance for natural gas ex-ploration and development in the western Sichuan Basin.

Some scholars have studied fractures in the Upper Triassic Xujiahe Formation of the western Sichuan Basin.Liao et al.(2002)and Zhang(2005) discussed the formation and distribution of frac-tures in typical structures of the western Sichuan Basin.They divided fractures into longitudinal ten-sion fractures,transverse tension fractures,detach-ment fractures,and shear fractures.They also ana-lyzed the timing of fracture formation using the electron spin resonance method(Wong and Yen, 2000)and carbon-oxygen stable isotope analysis of fracture-filling cements(calcite and quartz).These authors ascribed fracture development to structural curvature(fold-related fractures).Yu et al.(2006) emphasized that the north-south and east-west striking fractures in the Baimamiao structure were regional fractures and,thus,not fold related,and the northeast-southeast and northwest-southeast frac-tures were tectonic and related to local deformation. Differences in fracture intensity correlate with rock properties,such as rock type,porosity,and pres-ence of microlayering.Zhang(2003)and Xu et al. (2004)identified fractures and calculated frac-ture aperture,porosity,and permeability from log information.Zeng et al.(2007a,b)used the re-lationship of fractures with mineral grains to di-vide microfractures into three types:intragranular microfractures,grain-edge microfractures,and trans-granular microfractures.They analyzed factors con-trolling fracture occurrence and the relation between

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tectonic stress fields and tectonic fractures since the Late Triassic.

In this article,I discuss the distribution,charac-teristics,and origin of microfractures using micro-scopic data from 1300conventional thin sections from 944.2m (3097.8ft)of core from 29wells,135casting thin sections injected with epoxy from 10wells,228cuttings from 3wells,and 88scanning electron microscope samples from 6wells.Samples are from the Pingluoba,Qiongxi,and Baimamiao structures of the Upper Triassic Xujiahe Formation in the western Sichuan Basin.This article provides the first in-depth account of these fracture arrays in English.

GEOLOGIC SETTING Structure

The western Sichuan Basin is located on the east-ern side of the Longmen Mountain thrust belt and west of the middle Sichuan uplift (Figure 1).This foreland basin formed during the Late Triassic (Burchfiel et al.,1995;Chen and Wilson,1996;Guo et al.,1996;Tao,1999;Jia et al.,2003,2006;Yong et al.,2003).Two main groups of northeast-southwest and north-south thrusts and their as-sociated fold structures exist (Figure 2).The faults have high throw and have trace lengths of tens

of

Figure 1.Map showing location of the Longmen Mountain fold-thrust belt,western Sichuan Basin,and study area (small box).Lines are reverse faults.Bar indicates dip and arrow marks slip direction.P =Pingluoba gas field;Q =Qiongxi gas field;B =Baimamiao gas field.

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kilometers.Most faults cut the Upper Triassic to the Upper Jurassic strata,but several cut Cenozoic strata.Stratigraphy and Sedimentology

Before the Middle Triassic,the western Sichuan Basin was dominated by shallow marine carbonate deposition.From the Late Triassic,the depression was filled with continental detrital deposits with a gross thickness of more than 10,000m (32,810ft).Of these deposits,the Upper Triassic Xujiahe For-mation is the primary gas-bearing unit and the pri-mary exploration target.The Upper Triassic Xujiahe Formation is sandstone mixed with mudstone and coal streaks (Figure 3).Facies include alluvial fan,river,lake,swamp,and delta,with a thickness of 1000to 4000m (3281–13,124ft).The Upper Tri-assic Xujiahe Formation can be divided into five members from bottom to top,of which the first member is chiefly black shale,the second member is chiefly fine-to medium-grained sandstone,the third member is dark-gray and black shale with dark-gray siltstone,the fourth member is quartz sand-stone with thin shale,and the fifth member is black

to gray shale,argillaceous siltstone,and sandstone with coal streaks.Reservoir Attributes

The deltaic sandstone of the second member of the Xujiahe Formation is the principal gas reser-voir.The fourth member is the secondary gas res-ervoir.The first,the third,and the fifth members are source rocks in the western Sichuan Basin.

The main reservoir lithology of the Upper Tri-assic Xujiahe Formation is thick fine-to medium-grained feldspathic sandstone and arkose.Other reservoirs are in feldspathic quartz sandstone,quartz sandstone,and feldspathic lithic sandstone and ar-kose.The thickness of sandstone is more than 70%of that of the gross stratum.The burial depth of the Upper Triassic Xujiahe Formation is more than 3000m (9843ft),whereas the reservoir thickness is 200to 400m (656–1312ft).

The physical properties of the tight-gas sand-stone reservoir are obtained from core analysis.The porosities are measured from 25×50–mm columnar samples using the kerosene saturation method.

The

Figure 2.Structural cross section based on surface geology and seismic data.Line location is shown in Figure 1.P1indicates a well.

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Microfracture Origins,Upper Triassic Sichuan Basin,China

gas permeabilities are measured by the steady-state method under nitrogen axial flow.During the test, the peripheral pressure of core sample is from2.5 to3MPa(362.5–435psi),the entrance pressure of nitrogen into core sample is more than0.2MPa (29psi),and the steady time is3min.According to an analysis of13,000rock samples from the Zhongba,Xinchang,Xiaoquan,Baima,Qiongxi, and Pingluoba structures,the porosity of the Up-per Triassic Xujiahe Formation ranges between2 and6%,averaging4%.Permeability is mainly less than0.1md,averaging0.028md.So,this forma-tion is a typical tight reservoir of low porosity and ultralow permeability.

According to the data from thin sections and the scanning electronic microscope,about three quar-ters of the reservoir pores are secondary,and primary ones are only one quarter.The types of pores include solution-related intragranular pores,solution-related intergranular pores,moldic pores,intercrystal pores in clay minerals,remnant intergranular pores,and microfractures.The reservoirs can be classified as fractured in that they produce despite having low porosity,small pores,complicated pore configura-tions,poor connectedness,high water saturation—normally60to70%—and strong anisotropy.

Microfractures are the main factors improving the storage as well as the permeability of these tight sandstones.For example,from Monte Carlo cal-culations(Howard,1990)and from thin-section data in the Qiongxi gas field,the average porosity that can be ascribed to microfractures is0.86%, but this is27.1%of the total porosity in these tight sandstones.The average sandstone

intragranular Figure3.Schematic stratigraphy,source rock,and reservoir in the western Sichuan Basin.

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and intergranular porosities are only 3.17%.The average permeabilities caused by microfractures are 4.72md,a value 10.9times the pore permeability in these tight https://www.wendangku.net/doc/2f16948626.html,ing core analysis data,the relationship between permeability and poros-ity is shown in Figure 4.When samples have no microfractures,the permeabilities of samples are less than 0.1md.Several samples have microfrac-tures,and their permeabilities can exceed 1md.

The fractures have an obvious sensitivity to stress (Smart et al.,2001;Zeng et al.,2007c).As the scale and permeability of the fracture increase,the stress sensitivity increases (Zeng and Li,2009),so fracture porosity and permeability at reservoir condition will be lower than that at surface condi-tions.The existence of overpressure in the tight-gas sandstones and partial filling in some microfractures will greatly weaken the change in microfracture po-rosity and permeability caused by subsurface con-ditions in the western Sichuan Basin.Production History and Characteristics The western Sichuan Basin was the first natural-gas –producing area in China.In historical records of ancient China,several shallow wells drilled at the study area (located in Qionglai County,east of Qiongxi gas field)produced small quantities of natural gas for boiling salt 1800yr ago.The first natural-gas –producing well deeper than 1000m (3280ft)was drilled in 1835.The first commercial gas field near Mianyang began production in the 1970s.Since then,more than 300exploration and

production wells have been drilled,and more than 20gas fields have been discovered and produced.

Natural gas in the western Sichuan Basin is mainly distributed in the tight sandstone and con-trolled by structures and fractures.Natural gas fields generally have abnormally high pressures.During the initial stages of development,the natural gas output of any single well can vary widely,for exam-ple,more than 200×104m 3per day (7.063mmcf gas/day)in some wells and less than 1×104m 3(0.35315mmcf gas/day)in others at Qiongxi gas field.Because of deep burial,high formation frac-ture pressure,and other reasons,hydraulic stimu-lation has not been universally used in the Upper Triassic tight-gas sandstones (Sun et al.,2008).Sand fracturing was used in only a few wells at the center of the western Sichuan Basin.Now,acid treatment to improve formation damage during drilling and well completion and production is the primary stimulation method in the Upper Triassic tight-gas sandstones.With production,the natural gas out-put and formation pressure decreased,and the wa-ter cut increased (Figure 5).In some gas fields with active edge-water drive,water was subsequently produced in gas wells (Zhong,2002).

MICROFRACTURE TYPES

Microfractures can be divided into three types based on the relation of fractures to grains.I identified intragranular microfractures,grain-edge microfrac-tures,and transgranular microfractures (Table 1

).

Figure 4.Relationship between the permeability and porosity from 472core samples in the Upper Triassic Xujiahe Formation,Qiongxi gas field.

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Microfracture Origins,Upper Triassic Sichuan Basin,China

Intragranular microfractures,lying entirely with-in grains,are mainly irregular arrays within quartz and cleavage fractures in feldspar.They are devel-oped within quartz or feldspar grains and typical-ly are found where grains contact one another.They do not cut through the edge of mineral grains (Figure 6).Intragranular microfractures have ap-ertures less than 10m m and lengths equal to or smaller than grain size but locally have high densi-ties (Figure 7).

Grain-edge microfractures are associated and may be coincident with the grain boundary.They are mainly distributed at boundaries between min-eral grains along linear contacts (Figure 6),so that they can also be called intergranular microfractures.Grain-edge microfractures are narrow and short,with the apertures less than 10m m (Figure 8),al-though where they have experienced dissolution,a few are as large as 20m m.The intragranular and grain-edge microfractures are not only important storage space of natural gas,but also are channels that link tiny pores and increase connectivity in otherwise ultralow-permeability reservoir rocks.

In contrast with grain-scale microfractures,the transgranular (traversing grain)microfractures are wider and longer.Length is not restricted by the size of mineral grains.These fractures commonly cut across several mineral grains (Figure 9).Their apertures are generally less than 40m m,with peak values of 10to 20m m,but they may be more than 40m m after being widened by dissolution.

According to analysis of thin sections from 29wells,almost all contain intragranular microfrac-tures and grain-edge microfractures.Intragranular microfractures and grain-edge microfractures have high densities but small scales.Their effects on per-meability can be expected to be small,but because of their abundance,they are the main

microfracture

Figure 5.The typical production graphs of a well in the Qiongxi gas field.

Table 1.The Characteristics of Different Microfracture Types in the Tight-Gas Sandstones Microfracture Type Intragranular Microfractures Grain-Edge Microfractures Transgranular Microfractures Distribution Within coarse grain (quartz,feldspar)by linear contact Along coarse grain boundary by linear contact Traverse some grains and debris Length Several tens of microns Several tens of microns From hundreds of microns to several centimeters Aperture <10m m

<10m m <40m m,mostly 10–20m m Origin

Diagenesis and tectonism

Diagenesis

Tectonism,diagenesis,and overpressure

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storage in these reservoirs.Porosity associated with these fractures is comparable in magnitude to that of the matrix pore system.Thin sections with trans-granular microfractures are less common,comprising only 16%of all thin sections.The average number of transgranular microfractures is 2.4cm –1in each thin section,and their average surface density is 0.42cm –1.The density of transgranular microfrac-tures is higher around faults and on the high parts of structures (fold hinges).

MICROFRACTURE TECTONIC ORIGIN Among the three types of microfractures,most of the transgranular microfractures are tectonic.These tectonic microfractures are present in most sand-stone rock types.They are partly filled with calcite or quartz.The tectonic microfractures are long and have a regular distribution (Figure 10)and are part of the same macrofracture populations that are associated with folds and thrusts.In addition,some intragranular microfractures are also related to tec-tonic compression.

The timing of fractures was deduced from fluid inclusion of quartz and calcite deposits in

the

Figure 6.Intragranular microfractures and grain-edge micro-fractures in thin section from Qiongxi gas field from a depth of 3514.5m (11,530.5ft).Transmitted light image.A =intragranular microfracture formed within a crushed quartz grain;B =grain-edge microfracture present along grain boundary.Red is the epoxy

resin.

Figure 7.Intragranular microfracture within quartz from scan-ning electron microscopy at the depth of 4232.9m (13,887.5ft)in Qiongxi gas field.Secondary electron image.A and arrow indicate pore space in the open

microfracture.Figure 8.Grain-edge microfracture (A)along boundary of quartz grain (G),secondary electron image,specimen from depth of 4107.5m (13,476ft),Qiongxi gas

field.

Figure 9.Traversing grain microfracture in thin section from Qiongxi gas field at a depth of 3373.1m (11,066.6ft).The orange-stained material is epoxy in the fracture pore space.

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Microfracture Origins,Upper Triassic Sichuan Basin,China

tectonic microfractures (Laubach and Diaz-Tushman,2009).Raman microprobe spectrometer analysis shows that fluid inclusions are trapped during quartz and calcite-cement precipitation,mostly in the microfractures.Fluid inclusions,distributed as a string of beads or an oriented group,may be rect-angular or irregular or triangular.Typical inclu-sions in samples are smaller than 0.1mm.Many are vapor and liquid,and their proportion ranges from 5to 8%.Using methods outlined by Roedder (1984),I measured fluid-inclusion homogenization temper-atures in five samples collected from the Qiongxi gas field (Figure 1).Fluid-inclusion assemblages in five samples have homogenization temperatures that range from 75to 186°C and salinities of about 2.9to 7.6wt.%NaCl eq.These homogenization values and salinities are close to the values of 85to 163°C and salinities of about 2.5to 9.3wt.%NaCl eq.in three samples collected from the Pingluoba gas field (Figure 1)and 93to 168°C and salinities of about 3.2to 6.9wt.%NaCl eq.in one sample collected from Baimamiao gas field (Figure 1)re-ported by Li et al.(2009)for vein-filling quartz (of unspecified relative fracture age).

According to overlapping relations of minerals in fractures,their fluid-inclusion analysis,and burial history,I deduce three crack-filling events,showing that tectonic microfractures mainly formed in three tectonic events (Figure 11).The first event was at

the end of the Triassic,with fluid-inclusion ho-mogenization temperatures approximately 70to 90°C.The second event was at the end of the Cre-taceous,with fluid-inclusion homogenization tem-peratures more than 130°C.The third event was at the end of the Neogene to early Pleistocene,with fluid-inclusion homogenization temperatures from approximately 100to 120°C.The timing of these events agrees with inferences from carbon-and oxygen-stable isotope analysis and quartz electron spin resonance analysis of cement deposits in tec-tonic macrofractures (Liao et al.,2002;Zhang,2005;Yu et al.,2006).

OVERPRESSURE ORIGIN

I interpret some microfractures to be the result of overpressure because they are associated with veins filled with bitumen,and they may contain bitu-men themselves.A bitumen-filled microfracture generally is wide and short (Figure 12).Based on the geometry of these bitumen-filled microfractures,they are tensional veins,which are the products of tension stress,and the veins are perpendicular to the minimum principal stress direction.According to the tectonic environment,these special stress conditions are caused by the overpressure fluid,indicating that this area once experienced over-pressure (Wang et al.,2004a,b;Liu et al.,2005,2006).

According to analysis of formation mechanism of overpressure,burial history,and hydrocarbon generating in the western Sichuan Basin (Wang et al.,2004a,b),the overpressure began to form at the end of the Middle Jurassic.During the middle –Late Cretaceous,the maximum pressure coefficient was about 1.6to 2.1,which was 70to 90%of the upper strata static pressure.The existence of over-pressure can reduce the effective normal stress.This can be represented by a Mohr circle for stress that moves to the left,such that the minimum horizontal principal stress (s hmin )can be changed from posi-tive (compression stress)to negative (tensional stress)and can form the tensional microfractures filled with bitumen.Therefore,the tensional

fractures

Figure 10.Tectonic microfracture in thin section from Qiongxi gas field at depth of 3350.4m (10,992.1ft).A =the principal microfracture filled with bitumen;B =secondary microfractures parallel to the principal microfracture.

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can also indicate ancient overpressure in a sedi-mentary basin (Zeng et al.,2007d).

Cenozoic tectonic movements at the south of the western Sichuan Basin were intense,and the overpressures were released with fault activity and uplift as seals were breached.When pore-fluid pres-sure dropped to 60%of static pressure in the upper strata,the overpressure-related microfractures would close or could be filled with calcite (Figure 12).Thus,one can commonly see bitumen veins cut by calcite veins in the southern part of the western Sichuan Basin.According to fluid-inclusion anal-ysis from the Qiongxi gas field,the homogeniza-tion temperatures of these calcite veins are 110to 130°C,combined with paleogeothermal gradients and burial history analysis,the filling period for calcite veins was middle –late Neogene.This shows that overpressures were chiefly released in the middle –late Neogene,and the pressure coefficient after release was 1.2to 1.3.In contrast,at present,the stratum fluid-pressure coefficient in the west-ern Sichuan Basin is more than 1.5at the center,between Chengdu and Mianyang,and in the north,north of Mianyang.

DIAGENETIC ORIGIN

Microfractures are defined as diagenetic features that formed during physical diagenesis.Diagenetic fractures can be transgranular microfractures,intra-granular microfractures,and grain-edge microfrac-tures.Transgranular microfractures formed

during

Figure 11.Burial history,geotemperature history,and fluid-inclusion homogenization temperature of quartz and calcite deposits in the tectonic microfractures in the Upper Triassic tight-gas sandstones at the Qiongxi gas field (Q6well).Burial history was de-duced using compaction correction and regional denudation data.Geotemperature history was obtained by simulation using vitrinite reflectance data from Zhang et al.(2005).A =the first fracturing time from fluid-inclusion homogenization temperatures of 85to 93°C;B =the second fracturing time from fluid-inclusion homogenization temperatures of 130to 140°C;C =the third fracturing time from fluid-inclusion homog-enization temperatures of 106to

122°C.

Figure 12.Overpressure-related microfractures in thin section from the Qiongxi gas field at the depth of 3450.3m (11,319.9ft).A =bitumen;B =calcite.

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diagenesis are mainly present on the boundaries between sandstone and mudstone,parallel to the directional compaction fabric of platy minerals (and

thus parallel to bedding).They are especially well developed in argillaceous rocks (Figure 13).This type of diagenetic fracture commonly develops along microlayers,where layers bend,end,pinch,or branch,They are commonly filled with clay minerals.The intragranular microfractures and grain-edge micro-fractures are diagenetic fractures because they were formed during compaction.Grain-edge microfrac-tures commonly occurs together with intragranular microfractures.The more compacted the rock,the less debris is present in the rock;the rougher the grains that contact each other in a linear manner,the better the intragranular fractures and grain boundary fractures will be developed.The forma-tion of intragranular fractures is mainly related to intensive mechanical compaction.The formation of grain-edge microfractures is associated with in-tensive compaction and pressure solution.Accord-ing to diagenetic analysis,the time of formation of these diagenetic microfractures was mainly from the Late Triassic to Early Cretaceous (Figure 14

).

Figure 13.Diagenetic fracture along bedding plane and par-allel to platy minerals in thin section from the Qiongxi gas field at the depth of 3253.2m (10,673.2ft).A =solution pore along diagenetic

fracture.

Figure 14.Schematic map shows microfracturing sequences in the Upper Triassic Xujiahe Formation,western Sichuan Basin (modified from Zeng et al.,2007a).Data on paleotemperature,hydrocarbon generation,R 0(vitrinite reflectance),and porosity evolution come from Xu and Lin (1996)and Yang (2003).Data on the pressure coefficient come from Wang et al.(2004a,b)and Liu et al.(2005).Stress was measured by rock acoustic emission (AE)experiments (Ding and Shao,2001;Zeng et al.,2004).The AE experiment was conducted using a 4010series acoustic emission apparatus,a 300KN omnipotence compression machine,a strain transducer,and computers in the Geomechanical Opening Laboratory of Chinese Academy of Geological https://www.wendangku.net/doc/2f16948626.html,ed with permission from Earth Science –Journal of China University of Geosciences.

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DISCUSSION

Microfractures are commonly filled with quartz, calcite,bitumen,and clay minerals.Clay com-monly fills in diagenetic microfractures,bitumen is in overpressure-related microfractures,and quartz and calcite are in tectonic microfractures.Three crack-filling events in tectonic microfractures indicate that they were formed in three tectonic movements.

Therefore,the microfracturing sequences in the Upper Triassic Xujiahe Formation of the western Sichuan Basin can be divided as follows(Figure14). First,the diagenetic microfractures were formed under intensive diagenesis and were filled with clay minerals.Diagenesis analysis suggests that the for-mation time of diagenetic microfractures was from the Late Triassic to Early Cretaceous.Second,the tectonic microfractures formed in the Late Triassic, and they commonly filled with calcite deposits.Third, with strata reaching the greatest burial depth and generating overpressure in the Cretaceous,overpres-sures caused tensional microfractures filled with bi-tumen to form.Then,at the end of the Cretaceous, tectonic microfractures formed again because of compression and high fluid pressures;parts of these fractures filled with quartz.Finally,at the end of the Neogene–early Pleistocene,tectonic microfractures formed under intensive tectonic compression and a few microfractures were filled with calcite.

Overpressure universally existed in the fold-thrust belts of foreland basins in central and west-ern China,such as the western Sichuan Basin,the northern Tarim Basin,and the southern Junnggar Basin(Xu et al.,2000;Wang et al.,2004a,b;Zeng and Liu,2006).Overpressure can have an impor-tant impact on fracture formation and hydrocarbon migration and accumulation.Besides undercom-paction and hydrocarbon generation,tectonic com-pression is the primary origin of overpressure in the fold-thrust belts of foreland basins in central and western China(Xu et al.,2000;Wang et al.,2004a, b;Zeng and Liu,2006).Under intense tectonic compression,the pore volume of rocks was reduced. Because of adequate sealing by gypsum salt or mudstone beds,the fluids could not be squeezed out,and most of the tectonic compression stress was borne by pore fluids.This caused a rapid rise of pore-fluid pressure and formed the overpressure in the foreland of the fold-thrust belt(Zeng and Liu, 2006).When the coefficient of pressure reaches 1.8,the minimum principal stress can change from compression to tension,and thereby tensional frac-tures can be formed in the fold-thrust belt of the foreland basin.In the extensional basin of eastern China,overpressure can also be formed by under-compaction and hydrocarbon generation(Hao and Dong,2001).Overpressure is also the main factor forming microfactures in mudstones.Therefore,frac-tured mudstone reservoirs generally are found near hydrocarbon source rocks in the extensional basin in eastern China(Zhi et al.,2004;Huang,2005).

Tectonic microfractures are well developed in all of the gas fields and are the principal type in the Upper Triassic tight-gas sandstones of the west-ern Sichuan Basin.The intensity of tectonic micro-fracture is controlled by structure and lithology. The tectonic microfracture are better developed in the hanging wall of thrusts and fine-grained sand-stone.For example,the density of tectonic micro-fractures(the total length of microfractures per unit area)from section data is more than0.5/cm–1in the fine-grained sandstones of the hanging wall of the south-north thrust,where the gas production is more than50×104m3/day(17.6575mmcf gas/ day)from a single well.Diagenetic microfractures are asymmetrically developed in different struc-tures and are relative to debris content and com-paction.The intragranular and grain-boundary frac-tures have wide-ranging distribution but small extent and size similar to that of the matrix pores and are a factor in storage of gas.Diagenetic micro-fractures distributed along the microbedding plane are discontinuous and closed under peripheral pres-sure,and so contribute little to production.Micro-fractures related to overpressure are short,have poor connectivity,and are almost always filled with bitumen and calcite,and so contribute little to production despite big apertures. CONCLUSIONS

Three types of microfractures,intragranular,grain-edge,and transgranular microfractures,developed

1822Microfracture Origins,Upper Triassic Sichuan Basin,China

in the tight-gas sandstones of the western Sichuan Basin.Microfracture formation reflects tectonism, overpressuring,and diagenetic processes(compac-tion and pressure solution).

Tectonic microfractures formed during three periods.The first was under the influence of north-west to southeast shortening that accompanied for-mation of the western Sichuan foreland basin at the end of the Triassic.The second was during resumed folding and thrusting at the end of the Cretaceous. The third was from the end of the Neogene to the early Pleistocene when shortening was greatest.

Tensional microfractures related to overpressure formed in the middle–Late Cretaceous when the maximum pressure coefficients were1.6to2.1.In the middle–late Neogene,the pressure coefficient after release was less than1.3because of fault ac-tivity and tectonic uplift at the south of the western Sichuan Basin.However,overpressure still existed in the central and northern parts of the western Sichuan Basin.The existence of overpressure re-duced effective stress,promoting opening-mode fracture growth.Because of overpressure,the stress state can be altered from compression to tension in the fold-thrust belt,and tension fractures can form in a compressional tectonic setting.The existence of tension fractures can also be used as an indicator of ancient overpressure in a sedimentary basin.

Diagenetic fractures formed from the Late Triassic,when the foreland basin of the western Sichuan Basin formed,to the Early Cretaceous. Under rapid sedimentation and intense compac-tion,intragranular microfractures formed because of the crushing of quartz grains and cleavage in feldspar.At the same time,under the influence of compaction and pressure solution,diagenetic trans-granular microfractures formed along the micro-bedding planes and are parallel to the directional fabric of platy minerals.

The intragranular and grain-boundary fractures are developed discretely at different structures, have small size and permeability,and are a major factor in storage of gas.Tectonic microfractures controlled by fold thrust and lithology are devel-oped at all of the gas fields and have the largest contribution to gas production.Diagenetic micro-fractures distributed along the microbedding plane and microfractures related to overpressure have little contribution to gas production. REFERENCES CITED

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The way常见用法

The way 的用法 Ⅰ常见用法： 1)the way+ that 2)the way + in which（最为正式的用法） 3)the way + 省略（最为自然的用法） 举例：I like the way in which he talks. I like the way that he talks. I like the way he talks. Ⅱ习惯用法： 在当代美国英语中，the way用作为副词的对格，“the way+ 从句”实际上相当于一个状语从句来修饰整个句子。 1)The way =as I am talking to you just the way I’d talk to my own child. He did not do it the way his friends did. Most fruits are naturally sweet and we can eat them just the way they are—all we have to do is to clean and peel them. 2）The way= according to the way/ judging from the way The way you answer the question, you are an excellent student. The way most people look at you, you’d think trash man is a monster. 3）The way =how/ how much No one can imagine the way he missed her. 4）The way =because

The way的用法及其含义(二)

The way的用法及其含义（二） 二、the way在句中的语法作用 the way在句中可以作主语、宾语或表语： 1.作主语 The way you are doing it is completely crazy.你这个干法简直发疯。 The way she puts on that accent really irritates me. 她故意操那种口音的样子实在令我恼火。The way she behaved towards him was utterly ruthless. 她对待他真是无情至极。 Words are important, but the way a person stands, folds his or her arms or moves his or her hands can also give us information about his or her feelings. 言语固然重要,但人的站姿,抱臂的方式和手势也回告诉我们他(她)的情感。 2.作宾语 I hate the way she stared at me.我讨厌她盯我看的样子。 We like the way that her hair hangs down.我们喜欢她的头发笔直地垂下来。 You could tell she was foreign by the way she was dressed. 从她的穿著就可以看出她是外国人。 She could not hide her amusement at the way he was dancing. 她见他跳舞的姿势，忍俊不禁。 3.作表语 This is the way the accident happened.这就是事故如何发生的。 Believe it or not, that's the way it is. 信不信由你, 反正事情就是这样。 That's the way I look at it, too. 我也是这么想。 That was the way minority nationalities were treated in old China. 那就是少数民族在旧中

(完整版)the的用法

定冠词the的用法： 定冠词the与指示代词this ,that同源,有“那(这)个”的意思,但较弱,可以和一个名词连用,来表示某个或某些特定的人或东西. (1)特指双方都明白的人或物 Take the medicine.把药吃了. (2)上文提到过的人或事 He bought a house.他买了幢房子. I've been to the house.我去过那幢房子. (3)指世界上独一无二的事物 the sun ,the sky ,the moon, the earth (4)单数名词连用表示一类事物 the dollar 美元 the fox 狐狸 或与形容词或分词连用,表示一类人 the rich 富人 the living 生者 (5)用在序数词和形容词最高级,及形容词等前面 Where do you live?你住在哪? I live on the second floor.我住在二楼. That's the very thing I've been looking for.那正是我要找的东西. (6)与复数名词连用,指整个群体 They are the teachers of this school.(指全体教师) They are teachers of this school.(指部分教师) (7)表示所有,相当于物主代词,用在表示身体部位的名词前 She caught me by the arm.她抓住了我的手臂. (8)用在某些有普通名词构成的国家名称,机关团体,阶级等专有名词前 the People's Republic of China 中华人民共和国 the United States 美国 (9)用在表示乐器的名词前 She plays the piano.她会弹钢琴. (10)用在姓氏的复数名词之前,表示一家人 the Greens 格林一家人(或格林夫妇) (11)用在惯用语中 in the day, in the morning... the day before yesterday, the next morning... in the sky... in the dark... in the end... on the whole, by the way...

“the way+从句”结构的意义及用法

“tｈｅwａｙ+从句”结构的意义及用法 首先让我们来看下面这个句子: Ｒead the foｌloｗｉnｇpassagｅａnd talkａbout ｉt wi ｔh your classmaｔes．Try tｏｔeｌl whaｔyｏu thiｎk ｏf Tom aｎd ｏｆｔhe ｗay the chiｌｄrenｔrｅated ｈim. 在这个句子中，ｔhe waｙ是先行词,后面是省略了关系副词that或in whｉch的定语从句。 下面我们将叙述“the ｗaｙ+从句”结构的用法。 1.tｈe wａy之后，引导定语从句的关系词是tｈat而不是hoｗ,因此，<<现代英语惯用法词典＞＞中所给出的下面两个句子是错误的：Ｔhｉs is ｔｈeｗayｈowｉtｈａppened. This is the way how he ａlwａｙs treats me. 2．在正式语体中,thaｔ可被in which所代替;在非正式语体中，ｔhat则往往省略。由此我们得到theｗay后接定语从句时的三种模式：1) tｈe ｗaｙ＋ｔhａt-从句２）the way +ｉn whiｃh－从句3) the ｗay +从句 例如：Ｔｈe way(in whiｃh ，thａt) ｔhｅｓｅｃomｒade ｓloｏｋａｔｐrobｌems is wrong．这些同志看问题的方法

不对。 Ｔｈｅｗａy(that ,ｉn ｗhiｃh)yoｕ’ｒe doinｇit is comple ｔeｌy crａzy.你这么个干法,简直发疯。 Wｅａdmiｒｅd him for thｅｗay ｉｎｗhｉch he fａｃeｓdiｆficultieｓ． Waｌlａｃe ａｎd Ｄarwiｎｇreed ｏn the way ｉｎwhi ｃh ｄｉfｆｅrｅnt forms ｏf life had ｂegｕn.华莱士和达尔文对不同类型的生物是如何起源的持相同的观点。 Thｉs is ｔｈe ｗaｙ（tｈａｔ) hｅdｉd it. I lｉkeｄｔhe waｙ(ｔhat) ｓｈeｏｒganized ｔhe ｍeetｉng． 3.theｗay(tｈat)有时可以与hｏw(作“如何”解）通用。例如： That’s tｈe ｗaｙ(tｈaｔ) shｅspoke. = Tｈat’s how shｅspoke.

way 用法

表示“方式”、“方法”，注意以下用法： 1.表示用某种方法或按某种方式，通常用介词in(此介词有时可省略)。如： Do it (in) your own way. 按你自己的方法做吧。 Please do not talk (in) that way. 请不要那样说。 2.表示做某事的方式或方法，其后可接不定式或of doing sth。 如： It’s the best way of studying [to study] English. 这是学习英语的最好方法。 There are different ways to do [of doing] it. 做这事有不同的办法。 3.其后通常可直接跟一个定语从句(不用任何引导词)，也可跟由that 或in which 引导的定语从句，但是其后的从句不能由how 来引导。如： 我不喜欢他说话的态度。 正：I don’t like the way he spoke. 正：I don’t like the way that he spoke. 正：I don’t like the way in which he spoke. 误：I don’t like the way how he spoke. 4.注意以下各句the way 的用法： That’s the way (=how) he spoke. 那就是他说话的方式。 Nobody else loves you the way(=as) I do. 没有人像我这样爱你。 The way (=According as) you are studying now, you won’tmake much progress. 根据你现在学习情况来看，你不会有多大的进步。 2007年陕西省高考英语中有这样一道单项填空题： ——I think he is taking an active part insocial work. ——I agree with you_____. A、in a way B、on the way C、by the way D、in the way 此题答案选A。要想弄清为什么选A，而不选其他几项，则要弄清选项中含way的四个短语的不同意义和用法，下面我们就对此作一归纳和小结。 一、in a way的用法 表示：在一定程度上，从某方面说。如： In a way he was right.在某种程度上他是对的。注：in a way也可说成in one way。 二、on the way的用法 1、表示：即将来(去)，就要来(去)。如： Spring is on the way.春天快到了。 I'd better be on my way soon.我最好还是快点儿走。 Radio forecasts said a sixth-grade wind was on the way.无线电预报说将有六级大风。 2、表示：在路上，在行进中。如： He stopped for breakfast on the way.他中途停下吃早点。 We had some good laughs on the way.我们在路上好好笑了一阵子。 3、表示：(婴儿)尚未出生。如： She has two children with another one on the way.她有两个孩子，现在还怀着一个。 She's got five children，and another one is on the way.她已经有5个孩子了，另一个又快生了。 三、by the way的用法

The way的用法及其含义(一)

The way的用法及其含义（一） 有这样一个句子：In 1770 the room was completed the way she wanted. 1770年，这间琥珀屋按照她的要求完成了。 the way在句中的语法作用是什么？其意义如何？在阅读时，学生经常会碰到一些含有the way 的句子，如：No one knows the way he invented the machine. He did not do the experiment the way his teacher told him.等等。他们对the way 的用法和含义比较模糊。在这几个句子中，the way之后的部分都是定语从句。第一句的意思是，“没人知道他是怎样发明这台机器的。”the way的意思相当于how；第二句的意思是，“他没有按照老师说的那样做实验。”the way 的意思相当于as。在In 1770 the room was completed the way she wanted.这句话中，the way也是as的含义。随着现代英语的发展，the way的用法已越来越普遍了。下面，我们从the way的语法作用和意义等方面做一考查和分析： 一、the way作先行词，后接定语从句 以下3种表达都是正确的。例如：“我喜欢她笑的样子。” 1. the way+ in which +从句 I like the way in which she smiles. 2. the way+ that +从句 I like the way that she smiles. 3. the way + 从句(省略了in which或that) I like the way she smiles. 又如：“火灾如何发生的，有好几种说法。” 1. There were several theories about the way in which the fire started. 2. There were several theories about the way that the fire started.

way 的用法

way 的用法 【语境展示】 1. Now I’ll show you how to do the experiment in a different way. 下面我来演示如何用一种不同的方法做这个实验。 2. The teacher had a strange way to make his classes lively and interesting. 这位老师有种奇怪的办法让他的课生动有趣。 3. Can you tell me the best way of working out this problem? 你能告诉我算出这道题的最好方法吗？ 4. I don’t know the way (that / in which) he helped her out. 我不知道他用什么方法帮助她摆脱困境的。 5. The way (that / which) he talked about to solve the problem was difficult to understand. 他所谈到的解决这个问题的方法难以理解。 6. I don’t like the way that / which is being widely used for saving water. 我不喜欢这种正在被广泛使用的节水方法。 7. They did not do it the way we do now. 他们以前的做法和我们现在不一样。 【归纳总结】 ●way作“方法，方式”讲时，如表示“以……方式”，前面常加介词in。如例1； ●way作“方法，方式”讲时，其后可接不定式to do sth.，也可接of doing sth. 作定语，表示做某事的方法。如例2，例3；

the-way-的用法讲解学习

t h e-w a y-的用法

The way 的用法 "the way+从句"结构在英语教科书中出现的频率较高, the way 是先行词, 其后是定语从句.它有三种表达形式:1) the way+that 2)the way+ in which 3)the way + 从句(省略了that或in which),在通常情况下, 用in which 引导的定语从句最为正式,用that的次之,而省略了关系代词that 或 in which 的, 反而显得更自然,最为常用.如下面三句话所示,其意义相同. I like the way in which he talks. I like the way that he talks. I like the way he talks. 一.在当代美国英语中,the way用作为副词的对格,"the way+从句"实际上相当于一个状语从句来修饰全句. the way=as 1)I'm talking to you just the way I'd talk to a boy of my own. 我和你说话就象和自己孩子说话一样. 2)He did not do it the way his friend did. 他没有象他朋友那样去做此事. 3)Most fruits are naturally sweet and we can eat them just the way they are ----all we have to do is clean or peel them . 大部分水果天然甜润,可以直接食用,我们只需要把他们清洗一下或去皮.

way的用法总结大全

way的用法总结大全 way的用法你知道多少，今天给大家带来way的用法，希望能够帮助到大家，下面就和大家分享，来欣赏一下吧。 way的用法总结大全 way的意思 n. 道路,方法,方向,某方面 adv. 远远地，大大地 way用法 way可以用作名词 way的基本意思是“路,道,街,径”,一般用来指具体的“路,道路”,也可指通向某地的“方向”“路线”或做某事所采用的手段,即“方式,方法”。way还可指“习俗,作风”“距离”“附近,周围”“某方面”等。 way作“方法,方式,手段”解时,前面常加介词in。如果way前有this, that等限定词,介词可省略,但如果放在句首,介词则不可省略。

way作“方式,方法”解时,其后可接of v -ing或to- v 作定语,也可接定语从句,引导从句的关系代词或关系副词常可省略。 way用作名词的用法例句 I am on my way to the grocery store.我正在去杂货店的路上。 We lost the way in the dark.我们在黑夜中迷路了。 He asked me the way to London.他问我去伦敦的路。 way可以用作副词 way用作副词时意思是“远远地,大大地”,通常指在程度或距离上有一定的差距。 way back表示“很久以前”。 way用作副词的用法例句 It seems like Im always way too busy with work.我工作总是太忙了。 His ideas were way ahead of his time.他的思想远远超越了他那个时代。 She finished the race way ahead of the other runners.她第一个跑到终点,远远领先于其他选手。 way用法例句

the_way的用法大全教案资料

t h e_w a y的用法大全

The way 在the way+从句中, the way 是先行词, 其后是定语从句.它有三种表达形式:1) the way+that 2)the way+ in which 3)the way + 从句(省略了that或in which),在通常情况下, 用in which 引导的定语从句最为正式,用that的次之,而省略了关系代词that 或 in which 的, 反而显得更自然,最为常用.如下面三句话所示,其意义相同. I like the way in which he talks. I like the way that he talks. I like the way he talks. 如果怕弄混淆，下面的可以不看了 另外，在当代美国英语中,the way用作为副词的对格,"the way+从句"实际上相当于一个状语从句来修饰全句. the way=as 1)I'm talking to you just the way I'd talk to a boy of my own. 我和你说话就象和自己孩子说话一样. 2)He did not do it the way his friend did. 他没有象他朋友那样去做此事. 3)Most fruits are naturally sweet and we can eat them just the way they are ----all we have to do is clean or peel them . 大部分水果天然甜润,可以直接食用,我们只需要把他们清洗一下或去皮. the way=according to the way/judging from the way 4)The way you answer the qquestions, you must be an excellent student. 从你回答就知道,你是一个优秀的学生. 5)The way most people look at you, you'd think a trashman was a monster. 从大多数人看你的目光中,你就知道垃圾工在他们眼里是怪物. the way=how/how much 6)I know where you are from by the way you pronounce my name. 从你叫我名字的音调中,我知道你哪里人. 7)No one can imaine the way he misses her. 人们很想想象他是多么想念她. the way=because 8) No wonder that girls looks down upon me, the way you encourage her. 难怪那姑娘看不起我, 原来是你怂恿的

the way 的用法

The way 的用法 "the way+从句"结构在英语教科书中出现的频率较高, the way 是先行词, 其后是定语从句.它有三种表达形式:1) the way+that 2)the way+ in which 3)the way + 从句(省略了that或in which),在通常情况下, 用in which 引导的定语从句最为正式,用that的次之,而省略了关系代词that 或in which 的, 反而显得更自然,最为常用.如下面三句话所示,其意义相同. I like the way in which he talks. I like the way that he talks. I like the way he talks. 一.在当代美国英语中,the way用作为副词的对格,"the way+从句"实际上相当于一个状语从句来修饰全句. the way=as 1)I'm talking to you just the way I'd talk to a boy of my own. 我和你说话就象和自己孩子说话一样. 2)He did not do it the way his friend did. 他没有象他朋友那样去做此事. 3)Most fruits are naturally sweet and we can eat them just the way they are ----all we have to do is clean or peel them . 大部分水果天然甜润,可以直接食用,我们只需要把他们清洗一下或去皮.

the way=according to the way/judging from the way 4)The way you answer the qquestions, you must be an excellent student. 从你回答就知道,你是一个优秀的学生. 5)The way most people look at you, you'd think a trashman was a monster. 从大多数人看你的目光中,你就知道垃圾工在他们眼里是怪物. the way=how/how much 6)I know where you are from by the way you pronounce my name. 从你叫我名字的音调中,我知道你哪里人. 7)No one can imaine the way he misses her. 人们很想想象他是多么想念她. the way=because 8) No wonder that girls looks down upon me, the way you encourage her. 难怪那姑娘看不起我, 原来是你怂恿的 the way =while/when(表示对比) 9)From that day on, they walked into the classroom carrying defeat on their shoulders the way other students carried textbooks under their arms. 从那天起,其他同学是夹着书本来上课,而他们却带着"失败"的思想负担来上课.

The way的用法及其含义(三)

The way的用法及其含义（三） 三、the way的语义 1. the way=as（像） Please do it the way I’ve told you.请按照我告诉你的那样做。 I'm talking to you just the way I'd talk to a boy of my own.我和你说话就像和自己孩子说话一样。 Plant need water the way they need sun light. 植物需要水就像它们需要阳光一样。 2. the way=how（怎样，多么） No one can imagine the way he misses her.没人能够想象出他是多么想念她！ I want to find out the way a volcano has formed.我想弄清楚火山是怎样形成的。 He was filled with anger at the way he had been treated.他因遭受如此待遇而怒火满腔。That’s the way she speaks.她就是那样讲话的。 3. the way=according as （根据） The way you answer the questions, you must be an excellent student.从你回答问题来看，你一定是名优秀的学生。 The way most people look at you, you'd think a trash man was a monster.从大多数人看你的目光中,你就知道垃圾工在他们眼里是怪物。 The way I look at it, it’s not what you do that matters so much.依我看，重要的并不是你做什么。 I might have been his son the way he talked.根据他说话的样子，好像我是他的儿子一样。One would think these men owned the earth the way they behave.他们这样行动，人家竟会以为他们是地球的主人。

way的用法

一．Way：“方式”、“方法” 1.表示用某种方法或按某种方式 Do it (in) your own way. Please do not talk (in) that way. 2.表示做某事的方式或方法 It’s the best way of studying [to study] English.。 There are different ways to do [of doing] it. 3.其后通常可直接跟一个定语从句(不用任何引导词)，也可跟由that 或in which 引导的定语从句 正：I don’t like the way he spoke. I don’t like the way that he spoke. I don’t like the way in which he spoke.误：I don’t like the way how he spoke. 4. the way 的从句 That’s the way (=how) he spoke. I know where you are from by the way you pronounce my name. That was the way minority nationalities were treated in old China. Nobody else loves you the way(=as) I do. He did not do it the way his friend did. 二．固定搭配 1. In a/one way：In a way he was right. 2. In the way /get in one’s way I'm afraid your car is in the way， If you are not going to help，at least don't get in the way. You'll have to move－you're in my way. 3. in no way Theory can in no way be separated from practice. 4. On the way (to……) Let’s wait a few moments. He is on the way Spring is on the way. Radio forecasts said a sixth-grade wind was on the way. She has two children with another one on the way. 5. By the way By the way，do you know where Mary lives? 6. By way of Learn English by way of watching US TV series. 8. under way 1. Elbow one’s way He elbowed his way to the front of the queue. 2. shoulder one’s way 3. feel one‘s way 摸索着向前走；We couldn’t see anything in the cave, so we had to feel our way out 4. fight/force one’s way 突破。。。而前进The surrounded soldiers fought their way out. 5.. push/thrust one‘s way（在人群中）挤出一条路He pushed his way through the crowd. 6. wind one’s way 蜿蜒前进 7. lead the way 带路，领路；示范 8. lose one‘s way 迷失方向 9. clear the way 排除障碍，开路迷路 10. make one’s way 前进，行进The team slowly made their way through the jungle.

the way的用法大全

在the way+从句中, the way 是先行词, 其后是定语从句.它有三种表达形式:1) the way+that 2)the way+ in which 3)the way + 从句(省略了that或in which),在通常情况下, 用in which 引导的定语从句最为正式,用that的次之,而省略了关系代词that 或in which 的, 反而显得更自然,最为常用.如下面三句话所示,其意义相同. I like the way in which he talks. I like the way that he talks. I like the way he talks. 如果怕弄混淆，下面的可以不看了 另外，在当代美国英语中,the way用作为副词的对格,"the way+从句"实际上相当于一个状语从句来修饰全句. the way=as 1)I'm talking to you just the way I'd talk to a boy of my own. 我和你说话就象和自己孩子说话一样. 2)He did not do it the way his friend did. 他没有象他朋友那样去做此事. 3)Most fruits are naturally sweet and we can eat them just the way they are ----all we have to do is clean or peel them . 大部分水果天然甜润,可以直接食用,我们只需要把他们清洗一下或去皮. the way=according to the way/judging from the way 4)The way you answer the qquestions, you must be an excellent student. 从你回答就知道,你是一个优秀的学生. 5)The way most people look at you, you'd think a trashman was a monster. 从大多数人看你的目光中,你就知道垃圾工在他们眼里是怪物. the way=how/how much 6)I know where you are from by the way you pronounce my name. 从你叫我名字的音调中,我知道你哪里人. 7)No one can imaine the way he misses her. 人们很想想象他是多么想念她. the way=because 8) No wonder that girls looks down upon me, the way you encourage her. 难怪那姑娘看不起我, 原来是你怂恿的 the way =while/when(表示对比) 9)From that day on, they walked into the classroom carrying defeat on their shoulders the way other students carried textbooks under their arms.

“the-way+从句”结构的意义及用法知识讲解

“the way+从句”结构的意义及用法 首先让我们来看下面这个句子： Read the following passage and talk about it with your classmates. Try to tell what you think of Tom and of the way the children treated him. 在这个句子中，the way是先行词，后面是省略了关系副词that 或in which的定语从句。 下面我们将叙述“the way+从句”结构的用法。 1．the way之后，引导定语从句的关系词是that而不是how,因此，<<现代英语惯用法词典>>中所给出的下面两个句子是错误的：This is the way how it happened. This is the way how he always treats me. 2. 在正式语体中，that可被in which所代替；在非正式语体中，that则往往省略。由此我们得到the way后接定语从句时的三种模式：1) the way +that-从句2) the way +in which-从句3) the way +从句 例如：The way(in which ,that) these comrades look at problems is wrong.这些同志看问题的方法不对。

The way(that ,in which)you’re doing it is completely crazy.你这么个干法，简直发疯。 We admired him for the way in which he faces difficulties. Wallace and Darwin greed on the way in which different forms of life had begun.华莱士和达尔文对不同类型的生物是如何起源的持相同的观点。 This is the way (that) he did it. I liked the way (that) she organized the meeting. 3.the way(that)有时可以与how(作“如何”解)通用。例如： That’s the way (that) she spoke. = That’s how she spoke. I should like to know the way/how you learned to master the fundamental technique within so short a time. 4．the way的其它用法：以上我们讲的都是用作先行词的the way，下面我们将叙述它的一些用法。

定冠词the的12种用法

定冠词the的12种用法 定冠词the 的12 种用法，全知道?快来一起学习吧。下面就和大家分享，来欣赏一下吧。 定冠词the 的12 种用法，全知道? 定冠词the用在各种名词前面，目的是对这个名词做个记号，表示它的特指属性。所以在词汇表中，定冠词the 的词义是“这个，那个，这些，那些”，可见，the 即可以放在可数名词前，也可以修饰不可数名词，the 后面的名词可以是单数，也可以是复数。 定冠词的基本用法： (1) 表示对某人、某物进行特指，所谓的特指就是“不是别的，就是那个!”如： The girl with a red cap is Susan. 戴了个红帽子的女孩是苏珊。 (2) 一旦用到the，表示谈话的俩人都知道说的谁、说的啥。如：

The dog is sick. 狗狗病了。(双方都知道是哪一只狗) (3) 前面提到过的，后文又提到。如： There is a cat in the tree.Thecat is black. 树上有一只猫，猫是黑色的。 (4) 表示世界上唯一的事物。如： The Great Wall is a wonder.万里长城是个奇迹。(5) 方位名词前。如： thenorth of the Yangtze River 长江以北地区 (6) 在序数词和形容词最高级的前面。如： Who is the first?谁第一个? Sam is the tallest.山姆最高。 但是不能认为，最高级前必须加the，如： My best friend. 我最好的朋友。 (7) 在乐器前。如： play the flute 吹笛子

Way的用法

Way用法 A:I think you should phone Jenny and say sorry to her. B:_______. It was her fault. A. No way B. Not possible C. No chance D. Not at all 说明：正确答案是A. No way，意思是“别想！没门！决不！” 我认为你应该打电话给珍妮并向她道歉。 没门！这是她的错。 再看两个关于no way的例句： （1）Give up our tea break? NO way! 让我们放弃喝茶的休息时间？没门儿！ （2）No way will I go on working for that boss. 我决不再给那个老板干了。 way一词含义丰富，由它构成的短语用法也很灵活。为了便于同学们掌握和用好它，现结合实例将其用法归纳如下： 一、way的含义 1. 路线

He asked me the way to London. 他问我去伦敦的路。 We had to pick our way along the muddy track. 我们不得不在泥泞的小道上择路而行。 2. （沿某）方向 Look this way, please. 请往这边看。 Kindly step this way, ladies and gentlemen. 女士们、先生们，请这边走。 Look both ways before crossing the road. 过马路前向两边看一看。 Make sure that the sign is right way up. 一定要把符号的上下弄对。 3. 道、路、街，常用以构成复合词 a highway（公路），a waterway（水路），a railway（铁路），wayside（路边）

way与time的特殊用法

way/time的特殊用法 1、当先行词是way意思为”方式.方法”的时候,引导定语从句的关系词有下列3种形式： Way在从句中做宾语 The way that / which he explained to us is quite simple. Way在从句中做状语 The way t hat /in which he explained the sentence to us is quite simple. 2、当先行词是time时,若time表示次数时,应用关系代词that引导定语从句,that可以省略; 若time表示”一段时间”讲时,应用关系副词when或介词at/during + which引导定语从句 1.Is this factory _______ we visited last year? 2.Is this the factory-------we visited last year? A. where B in which C the one D which 3. This is the last time _________ I shall give you a lesson. A. when B that C which D in which 4.I don’t like the way ________ you laugh at her. A . that B on which C which D as 5.He didn’t understand the wa y ________ I worked out the problem. A which B in which C where D what 6.I could hardly remember how many times----I’ve failed. A that B which C in which D when 7.This is the second time--------the president has visited the country. A which B where C that D in which 8.This was at a time------there were no televisions, no computers or radios. A what B when C which D that