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Line 47: − − The deposition of the Brae [[sandstone]] member represents the influx of large volumes of coarse clastic material into the [[South Viking Graben]] area and [[Brae area|Brae]] subarea during the [[Kimmeridgian]]–[[Tithonian]] [[synrift]] from the Fladen Ground Spur area to the west ([[:file:M115CH10FG03.jpg|Figure 3]], [[:file:M115CH10FG05.jpg|Figure 5]]). During this time, coarse conglomeratic point-sourced [[deep water|deep-water]] fan-apron [[sediment]]s were deposited along the margins of the Fladen Ground Spur forming the proximal Brae fans, which are the reservoir intervals in the South, Central, and North Brae fields as well as the “Trees fields” in Block 16/12 to the south (including Larch, Birch, and Sycamore) and the “T Block” (16/17) fields (Tiffany, Toni, and Thelma). These proximal fan-apron systems were the source of sand-rich turbidity currents that fed finer grained clastic material into the deeper parts of the basin-floor area resulting in the deposition of sand-rich lobe sediments present within the reservoir intervals in the Miller, Kingfisher, and East Brae fields<ref name=Rooksby1991 /><ref name=Garland1993 /><ref name=Branter2003>Branter, S., 2003, The East Brae Field, Blocks 16/03a, 16/03b, UK North Sea, in J. G. Gluyas and H. M. Hichens, eds., United Kingdom oil and gas fields commemorative millennium volume: Geological Society (London) Memoir 20, p. 191–197.</ref><ref name=Spenceandkreutz2003 /> ([[:file:M115CH10FG01.jpg|Figure 1]], [[:file:M115CH10FG05.jpg|Figure 5]]).
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The Upper [[Jurassic]] Brae [[sandstone]] member can be [[stratigraphy|stratigraphically]] subdivided into a number of sub-intervals or zones based on the recognition and correlation of maximum flooding surface [[shale]]s from biostratigraphy and well log data sets. Based on the Shell stratigraphic scheme, the Brae sandstone member is subdivided into the Brae 1 and Brae 2 zones and each zone can in turn be further subdivided into two discrete sandstone units ([[:file:M115CH10FG04.jpg|Figure 4]]).
The Upper [[Jurassic]] Brae [[sandstone]] member can be [[stratigraphy|stratigraphically]] subdivided into a number of sub-intervals or zones based on the recognition and correlation of maximum flooding surface [[shale]]s from biostratigraphy and well log data sets. Based on the Shell stratigraphic scheme, the Brae sandstone member is subdivided into the Brae 1 and Brae 2 zones and each zone can in turn be further subdivided into two discrete sandstone units ([[:file:M115CH10FG04.jpg|Figure 4]]).
The deposition of the Brae [[sandstone]] member represents the influx of large volumes of coarse clastic material into the [[South Viking Graben]] area and [[Brae area|Brae]] subarea during the [[Kimmeridgian]]–[[Tithonian]] [[synrift]] from the Fladen Ground Spur area to the west ([[:file:M115CH10FG03.jpg|Figure 3]], [[:file:M115CH10FG05.jpg|Figure 5]]). During this time, coarse conglomeratic point-sourced [[deep water|deep-water]] fan-apron [[sediment]]s were deposited along the margins of the Fladen Ground Spur forming the proximal Brae fans, which are the reservoir intervals in the South, Central, and North Brae fields as well as the “Trees fields” in Block 16/12 to the south (including Larch, Birch, and Sycamore) and the “T Block” (16/17) fields (Tiffany, Toni, and Thelma). These proximal fan-apron systems were the source of sand-rich turbidity currents that fed finer grained clastic material into the deeper parts of the basin-floor area resulting in the deposition of sand-rich lobe sediments present within the reservoir intervals in the Miller, Kingfisher, and East Brae fields<ref name=Rooksby1991 /><ref name=Garland1993 /><ref name=Branter2003>Branter, S., 2003, The East Brae Field, Blocks 16/03a, 16/03b, UK North Sea, in J. G. Gluyas and H. M. Hichens, eds., United Kingdom oil and gas fields commemorative millennium volume: Geological Society (London) Memoir 20, p. 191–197.</ref><ref name=Spenceandkreutz2003 /> ([[:file:M115CH10FG01.jpg|Figure 1]], [[:file:M115CH10FG05.jpg|Figure 5]]).
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file:M115CH10FG05.jpg|{{figure number|5}}Simplified schematic map showing the depositional extent of the (A) South Brae and (B) North Brae submarine fan lobes within the Brae depositional system. Note that the South Brae and North Brae submarine fans correspond to the Brae 2 and Brae 1 intervals, respectively. Modified from Turner and Connell<ref name=Turnerandconnell1991 /> and Spence and Kreutz<ref name=Spenceandkreutz2003 />.
file:M115CH10FG05.jpg|{{figure number|5}}Simplified schematic map showing the depositional extent of the (A) South Brae and (B) North Brae submarine fan lobes within the Brae depositional system. Note that the South Brae and North Brae submarine fans correspond to the Brae 2 and Brae 1 intervals, respectively. Modified from Turner and Connell<ref name=Turnerandconnell1991 /> and Spence and Kreutz<ref name=Spenceandkreutz2003 />.
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During periods of cessation of deposition of the Brae [[conglomerate]]s and sands along the margins of the Fladen Ground Spur, and more distal parts of the basin to the east and northeast, the deposition of organic-rich hemipelagic [[shale]]s occurred in an overall anoxic basin-floor environment resulting in the deposition of the Kimmeridge Clay Formation, with which the Brae reservoirs interfinger. The Kimmeridge Clay Formation [[source rock]] generated much of the [[hydrocarbon]]s that have accumulated in, and been produced from, the [[Brae area]] fields as well as providing top, base, and lateral [[seal]]s to the hydrocarbon accumulations.
During periods of cessation of deposition of the Brae [[conglomerate]]s and sands along the margins of the Fladen Ground Spur, and more distal parts of the basin to the east and northeast, the deposition of organic-rich hemipelagic [[shale]]s occurred in an overall anoxic basin-floor environment resulting in the deposition of the Kimmeridge Clay Formation, with which the Brae reservoirs interfinger. The Kimmeridge Clay Formation [[source rock]] generated much of the [[hydrocarbon]]s that have accumulated in, and been produced from, the [[Brae area]] fields as well as providing top, base, and lateral [[seal]]s to the hydrocarbon accumulations.