Coupling 3D Geomechanics to Classical Petroleum System Simulation

Geomechanical models of classical petroleum system simulators are limited to 1D phenomenological laws relating porosity to vertical effective stress. In order to overcome this limitation, a 3D poromechanical model is integrated in the sedimentary basin simulation by applying an iterative coupling scheme between a conventional basin code and a mechanical finite element code. This paper presents the porous material constitutive law specifically devised to deal with basin modeling, together with essential aspects of the mechanical code implementation and explicit coupling workflow. The numerical procedure is first verified according to a semi-analytical solution and then compared to an implicit academic code. Finally, a 3D synthetic case demonstrates the importance of incorporating 3D geomechanics to basin simulation. The results show that tectonic compression may significantly contribute to overpressure development and natural fracturing of seal rocks, contrary to the standard procedures of petroleum system simulation which are unable to capture such effect

The Invisible Third. The Basque and Celtic Words for "Swallow"

In a keynote address at the XI. Fachtagung der Indogermanischen Gesellschaft, about possible non-Indo-European influence on the Celtic languages, Kim McCone drew attention to the similarity between the Insular Celtic, e.g. OIr fannall, W gwennol, and the Basque,i.e. enara, ain(h)- ara, words for 'swallow' (Lat hirundo). McCone reconstructs *waNilri or *weNrilri as preforms for the Insular Celtic words, and *(w)aiNala for Pre- Basque (McCone 2005,408-9).l This suggestion looks very attractive and suggestive and, if correct, would shed rare light on prehistoric linguistic relationships in Western Europe. In this article, I will examine the equation more closely and add a number of observations