Page 128 - The Petroleum System From Source to Trap

122 Morse

M E A N D E R I N G

GRAVEl AND SAND
THIN, HIGHtY INTERCONNECTED SAND BODIES
LOW GRADIENT
SAND AND MUD
THICK, lOCALLY ISOLATED SAND BODIES

Figure 6.1. Fluvial depositional models. (A) Braided river system idealized vertical section with tabular cross beds formed by
mid-channel bars and trough cross beds formed by migrating megaripples on the channel floor. (B) Block diagram of a
braided river. (C) Meandering river system with laterally aggrading point bars, highly sinuous channels, and thick fine­
grained overbank deposits (after LeBlanc, 1972). (D) Meandering river idealized vertical section with fining-upward, cross­
bedded point bar sands, finely laminated sands and silts, and overbank silt and clay (after Cant, 1982). Lithology pattern:
solid black, silt and clay size; large to small dots, conglomerate to sand size; patterned lines, bedding and cross-bedded
sandstone; combs, climbing ripple deposits.

Table 6.1 . Fluvial and Alluvial Reservoirs

Location Thickness Depositional
Field Country Basin Age a Formation of Pay (m) Environment
Hassi R'Mel Algeria Tr Hassi er Alluvial sands,
R'mel Ss anastomosing channels
Sarir Libya Sirte K Nubian equiv Fluvial-alluvial
of Sarir Ss
Mess Ia Libya Sirte K Sarir Ss 300 Stacked braided
channels
Hassi Messaoud Algeria Camb Ra Ss 1 2 0 Blanket ss
Amal Libya Sirte Camb-Ord Amal Ss Continental ss
October Egypt Carb-K Nubia Ss 1 3 5 Stacked fluvial channels,
blanket ss
Snorre Norway Tr Lunde Ss Braided to meandering,
Statfjord wide, shifting channels,
alluvial plain, blanket ss
McArthur River U.S.A. (Alaska) Olig Hemlock Cgl- Alluvial-fluvial
Kenai Ss
Dom Joao Brazil LK Sergi Ss Fluvial
Carmopolis Brazil Muribeca Alluvial fan and plains
Argentina J Challaco Ss Alluvial fans and plains
•L, lower; Camb, Cambrian; Ord, Ordovician; Garb, Carboniferous; Tr, Triassic; J, Jurassic; K, Cretaceous; Olig, Oligocene.
bA, anticline; Up, unconformity pinchout; 81, tilted block; St. stratigraphic; D, domal; WrA, wrench anticline.
cv, verticl; Lt, lateral.