Changes

! Regime || Class || Subclass || Family

! Regime || Class || Subclass || Family

|-

|-

| rowspan = 4 | ''Fluid-composition traps''; Result from a chemical property of the trapped oil or gas. || rowspan = 3 | ''Viscosity traps;'' Petroleum can be trapped by the presence of barriers created by highly [[Wikipedia:Viscosity|viscous]] oil ([[asphalt]], [[tar]]) or solid hydrocarbons ([[albertite]], [[gilsonite]], or [[grahamite]]). || ''Tar Seals'' || ''Bacterial degradation;'' Updip tar seal created by [[bacteria degradation]] of the hydrocarbons, preferentially removing the [[lighter fractions]].

| rowspan = 4 | ''Fluid-composition traps''; Result from a chemical property of the trapped oil or gas. || rowspan = 3 | ''[[Viscosity]] traps;'' Petroleum can be trapped by the presence of barriers created by highly viscous oil ([[asphalt]], [[tar]]) or solid hydrocarbons ([[albertite]], [[gilsonite]], or [[grahamite]]). || ''Tar Seals'' || ''Bacterial degradation;'' Updip tar seal created by [[bacteria degradation]] of the hydrocarbons, preferentially removing the [[lighter fractions]].

|-

|-

| colspan = 2 | ''Disseminated;'' Tar or asphalt fills the pores of [[shale]]s, [[sandstone]]s, or [[carbonate]]s. These traps are often called [[tar sands]], [[oil shale]]s, bituminous sandstones, or bituminous limestones.

| colspan = 2 | ''Disseminated;'' Tar or asphalt fills the pores of [[shale]]s, [[sandstone]]s, or [[carbonate]]s. These traps are often called [[tar sands]], [[oil shale]]s, bituminous sandstones, or bituminous limestones.

| colspan = 2 | ''Veins;'' The solid, essentially infusible form of petroleum is called [[pyrobitumen]]. It occurs in veins [[length::1 mm]] to [[length::8 m]] across and appears to have been injected or is a dead seepage.

| colspan = 2 | ''Veins;'' The solid, essentially infusible form of petroleum is called [[pyrobitumen]]. It occurs in veins [[length::1 mm]] to [[length::8 m]] across and appears to have been injected or is a dead seepage.

|-

|-

| colspan = 3 | ''Coal-bed methane;'' [[Coal bed]]s trap large volumes of [[Wikipedia:Methane|methane]], where most is [[Wikipedia:Adsorption|adsorbed]] onto internal surfaces of [[micropore]]s or along [[cleat face]]s. [[Coalification]] generates methane along with water, [[Wikipedia:Carbon dioxide|carbon dioxide]], and [[Wikipedia:Carbon monoxide|carbon monoxide]].

| colspan = 3 | ''[[Coal bed methane]];'' [[Coal]] beds trap large volumes of [[Wikipedia:Methane|methane]], where most is [[Wikipedia:Adsorption|adsorbed]] onto internal surfaces of [[micropore]]s or along [[cleat face]]s. [[Coalification]] generates methane along with water, [[Wikipedia:Carbon dioxide|carbon dioxide]], and [[Wikipedia:Carbon monoxide|carbon monoxide]].

|}

|}

[[Category:Traps, trap types, and the petroleum system]]  

[[Category:Traps, trap types, and the petroleum system]]  

[[Category:Classification of exploration traps]]

[[Category:Classification of exploration traps]]