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INTRODUCCION

INTRODUCCION

Magma is defined as a molten rock, which behaves as a viscous liquid generated multiple tectonic processes. The ascent to the fragile crust generates bodies of varying geometry. [[File:IMAGEN 1.png|thumbnail|Fig . 1. Types of magmatic bodies.]]

Magma is defined as a molten rock, which behaves as a viscous liquid generated multiple tectonic processes. The ascent to the fragile crust generates bodies of varying geometry (Fig 1). [[File:IMAGEN 1.png|thumbnail|Fig . 1. Types of magmatic bodies.]]

The morphology presented deployed such bodies depends on the viscosity, the amount of

The morphology presented deployed such bodies depends on the viscosity, the amount of

magma available, the list of regional efforts and magmas own composition. They can be

magma available, the list of regional efforts and magmas own composition. They can be

The focus of the article is aimed at magmatic bodies of small size (2-4 km in diameter and

The focus of the article is aimed at magmatic bodies of small size (2-4 km in diameter and

approximately 500 m thick) of laminar geometries and disposal consistent with available

approximately 500 m thick) of laminar geometries and disposal consistent with available

subhorizontal sedimentary rocks.  

subhorizontal sedimentary rocks(Fig 2).  

[[File:IMAGEN 2.png|thumbnail|Figure 2 : Schematic profile of the Neuquen Basin, province of Neuquen, Argentina , where you can see the site of lamellar bodies of Cenozoic age. Taken from Bermúdez & Delpino 2015.]]

[[File:IMAGEN 2.png|thumbnail|Figure 2 : Schematic profile of the Neuquen Basin, province of Neuquen, Argentina , where you can see the site of lamellar bodies of Cenozoic age. Taken from Bermúdez & Delpino 2015.]]

overcome the resistance of the rocks magma vertically looking for a new way of

overcome the resistance of the rocks magma vertically looking for a new way of

moving through a plane of weakness such as a stratigraphic unconformity,

moving through a plane of weakness such as a stratigraphic unconformity,

anisotropy of the medium as fault planes, hinges of folds, etc.

anisotropy of the medium as fault planes, hinges of folds, etc (Fig 3 and Fig 4).

[[File:IMAGEN 3.png|thumbnail|Figure 3: In this photograph the site of two sills can be seen in a bedrock (Vaca Muerta Fm). Right on the sector focuses it can be clearly seen intense fracturing of columnar pattern. Photo courtesy of Juan Spacapan.]]

[[File:IMAGEN 3.png|thumbnail|Figure 3: In this photograph the site of two sills can be seen in a bedrock (Vaca Muerta Fm). Right on the sector focuses it can be clearly seen intense fracturing of columnar pattern. Photo courtesy of Juan Spacapan.]]

Another important physical factor is the pore pressure. In porous sedimentary

Another important physical factor is the pore pressure. In porous sedimentary

reduced. This is why it can almost be deduced that the location of the intrusive

reduced. This is why it can almost be deduced that the location of the intrusive

within a sedimentary basin would be concentrated within shale formations (high

within a sedimentary basin would be concentrated within shale formations (high

porosity) with plenty of oil.

porosity) with plenty of oil (Fig 5 and Fig 6).

 

[[File:IMAGEN 5.png|thumbnail|Figure 5: Diagram relating the fluid pressure with the decrease in resistance of the country rock with increasing depth . Notice how the anisotropy of the medium magnify the value of T ( tensile stress) in the horizontal direction. Taken from Gressier et al 2010.]]

[[File:IMAGEN 5.png|thumbnail|Figure 5: Diagram relating the fluid pressure with the decrease in resistance of the country rock with increasing depth . Notice how the anisotropy of the medium magnify the value of T ( tensile stress) in the horizontal direction. Taken from Gressier et al 2010.]]

[[File:IMAGEN 6.png|thumbnail|Figure 6: experiment by Gressier et al 2010 made into a powder through diatomaceous saturated and unsaturated to simulate fluid through the sediment site. Magma was simulated with silicone caulk which behaves as an ideal Newtonian fluid. The conclusion of this experiment is that in a supersaturated fluid medium and the main effort horizontally oriented sill development is full.]]

[[File:IMAGEN 6.png|thumbnail|Figure 6: experiment by Gressier et al 2010 made into a powder through diatomaceous saturated and unsaturated to simulate fluid through the sediment site. Magma was simulated with silicone caulk which behaves as an ideal Newtonian fluid. The conclusion of this experiment is that in a supersaturated fluid medium and the main effort horizontally oriented sill development is full.]]

presumably has to do with three factors: pore pressure, level weakness is the bedrock

presumably has to do with three factors: pore pressure, level weakness is the bedrock

(being shale is less competent ) and plans anisotropy generated in the shales facilitate

(being shale is less competent ) and plans anisotropy generated in the shales facilitate

deflection of the levees that are rising from lower levels.

deflection of the levees that are rising from lower levels (Fig 7).

[[File:IMAGEN 7.png|thumbnail|Figure 7: Scheme of northern Neuquen basin where it can be seen as most sills are deployed in the Vaca Muerta Formation (hydrocarbon source rock).]]

[[File:IMAGEN 7.png|thumbnail|Figure 7: Scheme of northern Neuquen basin where it can be seen as most sills are deployed in the Vaca Muerta Formation (hydrocarbon source rock).]]

 Fracturing: as shown above for the location of magma is necessary to move adjacent

 Fracturing: as shown above for the location of magma is necessary to move adjacent

 Columnar or polygonal fractures: are generated by cooling and solidification of

 Columnar or polygonal fractures: are generated by cooling and solidification of

magma, where its volume is reduced contraction columnar cells formed orthogonal

magma, where its volume is reduced contraction columnar cells formed orthogonal

to the surface through which heat is lost.

to the surface through which heat is lost (Fig 8 and Fig 9).

[[File:IMAGEN 8.png|thumbnail|Figure 8: Scheme of columnar fractures. Taken from Bermúdez & Delpino 2015.]]

[[File:IMAGEN 8.png|thumbnail|Figure 8: Scheme of columnar fractures. Taken from Bermúdez & Delpino 2015.]]

[[File:IMAGEN 9.png|thumbnail|Figure 9: Variation of fracture patterns in a vertical section of a sill. Taken from Bermúdez & Delpino 2015.]]

[[File:IMAGEN 9.png|thumbnail|Figure 9: Variation of fracture patterns in a vertical section of a sill. Taken from Bermúdez & Delpino 2015.]]

• Folding: the movement of material not only produces fracturing but also the folding of

• Folding: the movement of material not only produces fracturing but also the folding of

the overlying material. These folds are important because they may constitute important

the overlying material. These folds are important because they may constitute important

reservoirs and traps, even exploited in several basins in the world.

reservoirs and traps, even exploited in several basins in the world (Fig 10).

[[File:IMAGEN 10.png|thumbnail|Figure 10: 2D seismic conducted northeast of Rockall basin, North Sea Norway. Observe normal faults as a product to accommodate the deformation of the fold. Taken from Hansen & Cartwright 2006.]]

[[File:IMAGEN 10.png|thumbnail|Figure 10: 2D seismic conducted northeast of Rockall basin, North Sea Norway. Observe normal faults as a product to accommodate the deformation of the fold. Taken from Hansen & Cartwright 2006.]]

• Thermal Maturity: the intrusion of magma of high temperatures (up to 1200 ° C) has a

• Thermal Maturity: the intrusion of magma of high temperatures (up to 1200 ° C) has a

thermal effect on the country rock can get to promote maturation of hydrocarbons when

thermal effect on the country rock can get to promote maturation of hydrocarbons when

diagenetic conditions are not optima.

diagenetic conditions are not optima (Fig 11).

[[File:IMAGEN 11.png|thumbnail|Figure 11: modeling of the distribution and direction of migration of oil and gas after the intrusion and cooling of a lacolito in the north of the Neuquen Basin and into the Vaca Muerta Fm province of Neuquen, Argentina ]]

[[File:IMAGEN 11.png|thumbnail|Figure 11: modeling of the distribution and direction of migration of oil and gas after the intrusion and cooling of a lacolito in the north of the Neuquen Basin and into the Vaca Muerta Fm province of Neuquen, Argentina ]]

to intense secondary patency generated both in the country rock and the same intrusive

to intense secondary patency generated both in the country rock and the same intrusive

given by fracturing the formation of stratigraphic traps as fold forced and effects thermal

given by fracturing the formation of stratigraphic traps as fold forced and effects thermal

maturity they produce hydrocarbons by high temperature.

maturity they produce hydrocarbons by high temperature (Fig 12,13 and 14).

[[File:IMAGEN 12.png|framed|left|Figure 12: first stage in the construction of a sill. The levels correspond to greenish mudstones ( E in very low resistance GPa) .]]

[[File:IMAGEN 12.png|framed|left|Figure 12: first stage in the construction of a sill. The levels correspond to greenish mudstones ( E in very low resistance GPa) .]]