Tesis
Determinación de los índices de fragilidad y fracturabilidad para definir intervalos a disparar en la formación pimienta en un pozo al Noroeste del Estado de Nuevo León.
Fecha
2017-12-11Registro en:
Coutiño Miranda, Carlos. (2016). Determinación de los índices de fragilidad y fracturabilidad para definir intervalos a disparar en la formación pimienta en un pozo al Noroeste del Estado de Nuevo León. . (Maestría en Geociencias y Administración de Recursos Naturales). Instituto Politécnico
Nacional, Sección de Estudios de Posgrado e Investigación, Escuela Superior de Ingeniería y
Arquitectura, Unidad Ticomán. México.
Autor
Coutiño Miranda, Carlos
Institución
Resumen
La Formación Pimienta actualmente en México ha adquirido gran interés debido a su potencial de producción de hidrocarburos. Esta Formación se ha clasificado como shale o lutita en español, aunque las pruebas de difracción de rayos x nos indican que la matriz es caliza, por la muy baja permeabilidad de la formación se estudia como lutita, ya que los sedimentos son del tamaño de la arcilla.
El desarrollo de yacimientos de lutita requiere el estudio de propiedades que en los yacimientos no convencionales no se toman en cuenta, por lo tanto en este trabajo se estudian esas propiedades las cuales son el contenido de carbón orgánico, mineralogía, propiedades elásticas y propiedades de resistencia de la roca. ABSTRACT
The Pimienta Play in Mexico nowadays has become so interesting due to its potential to
produce hydrocarbons. This play has classified like shale, although the x ray diffraction test
point us that the limestone is the matrix, because of the low permeability this play is
investigating like shale, since the sediments sizes are similar to clay sediments.
To develop shale reservoirs is required to study properties that in conventional reservoirs is
not required, therefore in this paper are analyzed those properties which are total organic
carbon, mineralogy, elastic properties and rock strength properties. These properties was
obtained from log well correlations and the accuracy of these correlation was analyzed whit
vertical well core plug laboratory tests.
Many brittleness index based in different rock properties were studied, the models were
applied whit laboratory test and some whit logs of vertical well. The fracability index was
other concept studied which uses brittleness index, release strain energy and fracture
toughness, this model was calculated from logs of vertical well.
The results of the different brittleness models were analyzed regarding mineralogy and
compared to each other and it concluded that the brittleness index model proposed by
Rickman could undervalue or overvalue the brittliness. Three brittleness models calculated
whit different rock properties have similar trend and are logical regarding mineralogy.
The fracability index was analyzed in the vertical well and was noted that it not always
increases where brittleness increases, because of the release strain energy and fracture
toughness not always follow the brittleness index trend, so that not always an interval whit
high brittleness index would has a high fracability index.
Due to the compressional and shear transit time logs in horizontal well were not available,
neural network technique was applied to generate them onset the available logs of
horizontal well. First, neural network was applied in Pimienta Play whit the logs of vertical
well, the output values of neural network were compared regarding the real values of
compressional and shear transit time and then coefficient R2 was obtained to guarantee
the reliability of output logs.
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Once that the transit time of horizontal well were obtained, the elastic properties and rock
strength properties were calculated onset the correlation that shown the best performance
in the vertical well. The brittleness and fracturability index models were calculated and
analyzed and then was chosen a model to determine the intervals to penetrate.
Finally the best intervals to perforate was determined in the horizontal well by means of an
integral analysis of fracability index, minimum horizontal stress and clay volume.