Thermal histories of sedimentary basins and compaction of sediments
Thermal models for sedimentary basins in two different tectonic settings are presented. The first applies to basins in extensional settings such as pull-apart basins or passive continental margins. These basins subside due to cooling of the underlying lithosphere after the initial rifting event. Heat flow may be very high initially but decreases with time as the lithosphere thickens. An analytic model is presented which predicts basin depth, strata depths, and sediment temperatures. A second model is developed to predict the thermal history of sediments in thrust belts. Immature sediments may be rapidly heated if buried beneath an advancing thrust sheet. The thrust plate acts as a thermal blanket, insulating the underlying sediments. An oil generation model, used in conjunction with the thermal model, shows that oil generation in the underlying sediments is greatly enhanced as a result of thrust plate emplacement. The petroleum maturation history of the Fossil Basin in the Idaho-Wyoming thrust belt is considered. Another important sedimentological problem concerns the compaction of sandstones. A one-dimensional model for the compaction of quartz arenites by pressure solution and precipitation is developed. Quartz grains are assumed to dissolve at highly stressed pore walls, thus reducing porosity. Important factors determining the porosity history are grain size, thermal gradient and sedimentation rate. The results compare well with data on primary porosity destruction in quartz arenites.
- OSTI ID:
- 5721028
- Country of Publication:
- United States
- Language:
- English
Similar Records
Sedimentary loading, lithospheric flexure and subduction initiation at passive margins
Geothermal regime and thermal history of the Llanos Basin, Columbia
Related Subjects
020200* -- Petroleum-- Reserves
Geology
& Exploration
58 GEOSCIENCES
580100 -- Geology & Hydrology-- (-1989)
580300 -- Mineralogy
Petrology
& Rock Mechanics-- (-1989)
CATAGENESIS
COMPACTING
ENERGY SOURCES
FEDERAL REGION VIII
FOSSIL FUELS
FUELS
GEOLOGIC STRUCTURES
MATHEMATICAL MODELS
MATURATION
NORTH AMERICA
PETROLEUM
ROCKS
SANDSTONES
SEDIMENTARY BASINS
SEDIMENTARY ROCKS
USA
WESTERN US OVERTHRUST BELT
WYOMING