000 02337nab a2200217 4500
005 20260520000317.0
008 260224s2014 xxu ing
041 _aInglés
245 0 0 _aThe concept of joint saturation and its application
260 _a
_b
_cnov. 2014
270 _a15/12/2014 ; 15/12/2014
300 _a17 p. ; 2347-2364
520 _aTranscripción del resumen del autor: Two of the major joint-driving mechanisms are joint-normal stretching and poroelastic shrinkage, and these lead to joint sets commonly associated with structural bending and natural hydraulic fracturing, respectively. Regardless of joint-driving mechanism, joint infilling is a nonhomogeneous Poisson process in the presence of stress shadows. Through probability modeling, we show that in all cases joint spacing is best fit with gamma distributions. The shape parameter of the best-fit gamma distribution to joint-spacing data is a quantitative means to assess the extent of saturation, which is represented in a new parameter, the joint-saturation ratio (JSR). To test the utility of JSR, we call upon published structural bending joint data (Elk Basin, Lilstock, and Rives plate-bending experiment). The shape parameters for these well-developed structural bending joints are equal to around three, corresponding to a JSR of approximately 30%. Using the same analysis on the spacing of natural hydraulic fractures collected from outcrops in the gas-prone Devonian sections of the Appalachian Basin, we find that natural hydraulic fractures differ in two aspects from structural bending joints. First, the joint spacing is proportional to bed thickness in bedded rocks but not in gas shale sections. Second, the joint saturation of natural hydraulic fractures is generally lower than in well-developed structural bending joints. Thus, the JSR is a means to distinguish the joint-driving mechanism and to represent joint-saturation level independent of bed thickness effects. It can be used to distinguish natural fractures from drilling-induced fractures and to improve the fracture-network modeling.
581 _a11
773 0 _tAAPG Bulletin
_g98
942 _cARTICULO
100 1 _aTan, Yunhui
_954305
100 1 _aJohnston, Thomas
_954306
100 1 _aEngelder, Terry
_944354
999 _c188709
_d188709