Compaction and Porosity Reduction in Carbonates: A Review of Observations, Theory, and Experiments

Abstract

1 heprtment of qeosienesD niversity of ysloD ox IHPRD HQIT ysloD xorwy 2 serreD niversit e qrenole s nd gxD f SQD QVHRI qrenoleD prne 3 hysis of qeologil roessesD niversity of ysloD ox IHRUD HQIT ysloD xorwy Abstract grontes re mjor sedimentry mterils found in mny upper lyers of the irth9s rustF nderstnding their omption ehviour is importnt for porosity predition in sedimentry sins nd to improve the knowledge out seling of tive fults t shllow depthsD where the fults rossEut limestone formtionsF sn rontesD s opE posed to siliilsti sedimentsD digenesis strts t shllow depths @<I kmA nd n ontriute to the formtion of mehnilly stle solid frmeworkF ertil stressD grin size nd ly ontent re the min prmeters inuening mehnil omptionF wehnil omption of unonsolidted ronte snds in lortory ours mostly t low stress nd is minly ontrolled y minerlogy nd initil pking of grinsF st n explin porosity redution down to out QH7F gonverselyD very little porosity loss @< I7A is otined y mehnil omption of emented roks under lortory ondiE tionsF sn sedimentry sinsD howeverD muh lower porosity vlues re usully enounE teredD down to zeroF qiven tht mehnil omption does not explin stisftorily porosity{depth trends oserved in sedimentry sinsD the eet of hemil omption on porosity must e onsideredF emong hemil mehnismsD pressure solution reep involves lol mss trnsfer y dissolutionD diusion nd preipittion proesses t the grin sleF uritil rk growth is lso uid ssisted proess ontriuting to grin frgmenttion nd omption y rerrngement of prtilesF ressure solution reep strin rte depends on grin sizeD porosityD pplied stressD uid hemistryD nd tempertureF ghemil omption y pressure solution reep eomes n eetive proess of porosity redution from less thn one kilometer of depthD s soon s uids re presentF he min prmeters ontrolling porosity loss then eome vertil stressD tempertureD diusive ow nd pore uid hemistryF foth mehnil nd hemil I omption n led to either pervsive omption or lolized deformtionF he efE fet of the dierent prmeters nnot esily e dierentited in oservtions of nturl smplesD s vrious deformtion proesses our nd intert simultneouslyF roweverD ontrol prmeters my e seprted in speilly designed theoretil studies nd lortory experimentsF o frD few experimentl studies hve een performed on pressure solution reep nd suritil rk growth in rontesF greep experiments on lite powder nd indenE ters experiments hve shown tht timeEdependent omption requires the presene of wterF iven though the dierent ontrolling prmeters were testedD no ler onsensus exists on the rte limiting step of deformtion ndD onsequentlyD on the reep lwF sndividul proesses leding to porosity loss in rontes re rther well identiedF roweverD their respetive importne during uril is still detedF iven t shllow uril @<I kmA hemil omption is needed to explin the gp etween porosity loss otined during experimentl mehnil omption nd porosityEdepth urves from sedimentry sinsF he present study reviews vrious proesses t work durE ing ronte omption nd synthesizes the urrent understnding on the respetive importne of ...

Stylolites in limestones: Barriers to fluid flow?

“…Stylolites are complex column-and-socket interdigitation features that form as a result of intergranular pressure solution (e.g., Nenna and Aydin, 2011;Croizé et al, 2013). They are a common product of strain localization in sedimentary rocks and can form laterally extensive, planar drapes (some stylolites are known to reach lengths of almost 1 km; Safaricz and Davison, 2005).…”

Fractional factorial design for studying uranium carbonate leaching of Tahaggart's ore

“…The interaction temperaturecarbonate dosage shows that at a high level of temperature, adding more carbonates promotes uranium recovery, while the inverse behavior was noticed at low temperature. This could be ascribed to enhanced kinetics of carbonates dissolution with temperature increase (Croizé et al, 2013). Extracting uranium from the ore matrix is selectively dividing uranium minerals between the solid and the leaching reagent.…”

Fundamental controls on fluid flow in carbonates: current workflows to emerging technologies

“…Efforts to learn more of the interplay between multiple processes during carbonate compaction, and the relative importance of thermodynamic and petrophysical and fluid parameters Croizé et al 2013), provide a way to strengthen model algorithms incorporating both strain rates and the formation and morphology of stylolites (Angheluta et al 2012). Combined experimental and outcrop observations have provided new insights into the role of multiscale heterogeneities in limestones in localizing stylolites and their influence on the distribution of pressure solution in the surrounding reservoir rock (Ebner et al 2010).…”

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