Braided stream reservoirs
Two types of river deposits commonly are excellent reservoirs - braided and meandering streams. Some of the world's larger sandstone reservoirs are composed of braided stream deposits. Much of the Prudhoe Bay field on Alaska's North Slope and the Stratfjord reservoirs in the Statfjord and Brent fields in the North Sea contain sands deposited by braided streams. Braided streams are complex networks of low-sinuosity channels that flow on alluvial plains with slopes greater than 1 1/2 to 2/sup 0/ (0.026 to 0.034 rad). Discharge through the channels is normally low, but during a year sporadic floods carry enormous volumes of water and sediments into the system. As existing channels are overloaded with deposits during a flood, new channels are cut and quickly filled with coarser debris. Repeated bar formation and branching of channels produces the network of braided channels. The water that spills over the channel banks spreads fine silt and clay particles that are then deposited in abandoned channels and on the plain. During geologic time, the stream complex may move its location back and forth across the width of a valley floor many times. As the streams move into a new area during a flood, the channels will generally cut into and erode away previous deposits of clay and silt from the valley floor but may leave remnants of thicker shale layers in abandoned stream channels.
- Research Organization:
- Richardson, Sangree and Sneider
- OSTI ID:
- 5537189
- Journal Information:
- J. Pet. Technol.; (United States), Journal Name: J. Pet. Technol.; (United States) Vol. 39:12; ISSN JPTJA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Use of a computer simulation model to analyze processes that created braided-stream deposits of Ivishak Formation, Prudhoe Bay Field, Alaska
Gwembe Coal Formation, Karoo Supergroup, Mid-Zambezi valley, southern Zambia; a fluvial plain environment
Related Subjects
020200* -- Petroleum-- Reserves
Geology
& Exploration
03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
ARCTIC OCEAN
ATLANTIC OCEAN
BAYS
BEAUFORT SEA
CLAYS
DEPOSITS
DISASTERS
EXPLORATION
FLOODS
GEOLOGIC DEPOSITS
HYDROLOGY
MINERAL RESOURCES
NATURAL GAS DEPOSITS
NORTH SEA
PETROLEUM DEPOSITS
PRUDHOE BAY
RESERVOIR ROCK
RESOURCES
ROCKS
SANDSTONES
SEAS
SEDIMENTARY ROCKS
SEDIMENTS
SHALES
SILT
SURFACE WATERS