Research Article

The Exquisite Comparison of Shale Mineralogical-Geochemical Characteristics between Chang 7 Member and Chang 9 Member in Yanchang Formation, Ordos Basin

Table 2

Mineralogy of 60 Yanchang shale samples.

NumberDepth (m)Member/SMKaoliniteChloriteIlliteIllite/smectite mixed layerIllite/smectite mixed layer ratioClay mineralsQuartzK-feldsparPlagioclaseCalciteDolomitePyriteSiderite

11609.95C7-2SM0372736155530780000
21613.1C7-2SM0312445156522760000
31620.01C7-2SM010315915313171204150
41201.47C7-2SM0292843154836880000
51203.47C7-2SM0182854155429860300
61209.42C7-2SM0192655155133790000
71212.53C7-2SM01329581540288190023
81451.1C7-2SM10162549155727560050
91452.37C7-2SM16183630155726590030
101454.42C7-2SM9102655156323770000
111455C7-2SM02324531548285710020
121457.04C7-2SM0192457205629750003
131139.1C7-2SM081280155330780020
141145.2C7-2SM4931137204837280302
151146.16C7-2SM4318752045362100304
161152.35C7-2SM10132156155730760000
171155.45C7-2SM151622471539296900170
181443.77C7-2SM01726571551263401600
191446.15C7-2SM01627571543358100040
201447.28C7-2SM0232453204531965040
211449.49C7-2SM01226621537317900160
221511.17C7-2SM0142957155923580050
231516.86C7-2SM0182161155630680000
241518.62C7-2SM02525501555296100000
251519.55C7-2SM0252352155130650080
261608.98C7-3SM9221681544180430031
271609.18C7-3SM94226515512241010012
281611.42C7-3SM7724621550223141019
291611.46C7-3SM8817671550183710813
301613.08C7-3SM4523681550220830215
311613.68C7-3SM0102268155030083018
321619.02C7-3SM12187915421311216223
331620.38C7-3SM0521741549252152043
341621.45C7-3SM2421731539283173028
351386.54C7-3SM042076154319495929
361386.58C7-3SM042373154620496339
371388.2C7-3SM0723701550225131027
381392.02C7-3SM05247115482431400011
391392.46C7-3SM0624701548272113027
401399.05C7-3SM0722711556232120034
411399.08C7-3SM0822701550280160024
421399.37C7-3SM07227115432501720130
431750.3C9M01127621544363113030
441755.28C9M0223048155339060020
451753.25C9M015275815413001405100
461754.43C9M111088154546020610
471360C9M0233938154342280320
481362.17C9M0183547154737082240
491364.02C9M01518671544410123000
501365.15C9M02528471540470103000
511603.35C9M01731521544362130230
521603.73C9M072568154240191610
531604.16C9M01723601552294110040
541604.66C9M01622621541354123050
551597.2C9M0243244104936080340
561663.39C9M0192556156423560020
571667.36C9M0152065155533090030
581668.27C9M01625591548323113030
591671.39C9M01021691555320100030
601671.89C9M01533521545380140030

Note: SM means submember. Unit of mineral composition is percentage (%). The percentage of types of clay minerals (e.g., kaolinite and illite) is relative to the clay mineral section rather than the whole rock.