Changes

==Data requirements==

==Data requirements==

Basic data requirements for facies analysis of subsurface rocks are listed in Table 1. Data associated with wells are most often used, but [[seismic data]], particularly [[3-D seismic: the data cube|three-dimensional data]], are becoming increasingly important in defining sandstone body geometries.<ref name=pt06r17>Brown, A. R., 1986 Interpretation of three-dimensional seismic data: [http://store.aapg.org/detail.aspx?id=1025 AAPG Memoir 42], 194 p.</ref>  Conventional core is perhaps the most diagnostic for sedimentological interpretation of vertical sequences (see [[Core description]]). However, wireline tools such as [[dipmeters]] and [[Borehole imaging devices|formation imaging devices]] can provide electrical images suitable for sedimentological interpretation with the added ability to determine [[paleocurrent]] directions in appropriate cases.

Basic data requirements for [[facies analysis]] of subsurface rocks are listed in Table 1. Data associated with wells are most often used, but [[seismic data]], particularly [[3-D seismic: the data cube|three-dimensional data]], are becoming increasingly important in defining sandstone body geometries.<ref name=pt06r17>Brown, A. R., 1986 Interpretation of three-dimensional seismic data: [http://store.aapg.org/detail.aspx?id=1025 AAPG Memoir 42], 194 p.</ref>  Conventional core is perhaps the most diagnostic for sedimentological interpretation of vertical sequences (see [[Core description]]). However, wireline tools such as [[dipmeters]] and [[Borehole imaging devices|formation imaging devices]] can provide electrical images suitable for sedimentological interpretation with the added ability to determine [[paleocurrent]] directions in appropriate cases.

{| class = "wikitable"

{| class = "wikitable"

===Lithofacies===

===Lithofacies===

One of the first steps in the facies analysis of a clastic reservoir is the description and interpretation of available conventional core.<ref name=pt06r119>Siemers, C. T., and R. W. Tillman, 1981, Recommendations for the proper handling of cores and sedimentological analysis of core sequences, in C. T. Siemers, R. W. Tillman, and C. R. Williamson, eds., Deep-Water Clastic Sediments—A Core Workshop: SEPM Core Workshop, n. 2, p. 20–44.</ref> An important result of [[core description]] is the subdivision of cores into ''lithofacies'', defined as subdivisions of a sedimentary sequence based on lithology, grain size, physical and biogenic sedimentary structures, and stratification that bear a direct relationship to the depositional processes that produced them. Lithofacies and lithofacies associations (groups of related lithofacies) are the basic units for the interpretation of depositional environments.

One of the first steps in the [[facies analysis]] of a clastic reservoir is the description and interpretation of available conventional core.<ref name=pt06r119>Siemers, C. T., and R. W. Tillman, 1981, Recommendations for the proper handling of cores and sedimentological analysis of core sequences, in C. T. Siemers, R. W. Tillman, and C. R. Williamson, eds., Deep-Water Clastic Sediments—A Core Workshop: SEPM Core Workshop, n. 2, p. 20–44.</ref> An important result of [[core description]] is the subdivision of cores into ''lithofacies'', defined as subdivisions of a sedimentary sequence based on lithology, grain size, physical and biogenic sedimentary structures, and stratification that bear a direct relationship to the depositional processes that produced them. Lithofacies and lithofacies associations (groups of related lithofacies) are the basic units for the interpretation of depositional environments.

===Depositional environments===

===Depositional environments===