Twenty years of sedimentary change and diagenesis, Qatar Peninsula, Arabian Gulf

Conference · Fri Jan 01 00:00:00 EST 1988

OSTI ID:6083067

Shinn, E A

Re-examination in February 1986 of areas studied by the author in 1966 and 1967 revealed rapid rates of sedimentation and diagenesis along the east coast of the Qatar Peninsula. At Ras UmSa on the northeast side of Qatar, a series of chenier-like beaches and curved spits is building southward under the influence of longshore currents. Beach and spit growth increasingly protects the shoreline and allows tidal flats to form in their lee. As these spits accrete, they become armored on their lagoonal side by beachrock formation. In the last 20 years a spit approximately 1/2 km long has grown, and beachrock has already armored its recurved lagoonal side. At Umm Said on the southeast side of Qatar, seawardly accreting barchan dunes composed of quartz sand have built a 40-km long, 10-km wide sabkha as thick as 30 m. Aerial and ground photographs show that certain dunes near the seaward edge of the sabkha have migrated into the sea and have contributed to shoreline accretion. The observed rate of dune migration suggests that within approximately 100 years the remaining quartz sands are depleted and blown into the sea because there is no replenishment of the dune field. Subsequently, the area reverts to one of carbonate deposition. Fine-grained dolomite is presently precipitating in interstitial brines in the landwardmost portions of this unusual sabkha. In the geologic record, such a deposit would be an anomalous, porous and permeable, cross-bedded, linear, 30-m thick, dolomite-cemented sandstones body encased in carbonate sediments. A modern model such as the one at Umm Said can provide useful clues for determining the origin of similar deposits in ancient rocks.

• OSTI ID: 6083067
• Report Number(s): CONF-880301-
• Resource Relation: Conference: Annual meeting of the American Association of Petroleum Geologists, Houston, TX, USA, 20 Mar 1988
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
03 NATURAL GAS
ARABIAN SEA
PETROLEUM GEOLOGY
NATURAL GAS DEPOSITS
GEOLOGIC HISTORY
PETROLEUM DEPOSITS
BRINES
CARBONATE ROCKS
CATAGENESIS
COASTAL REGIONS
COASTAL WATERS
DOLOMITE
EXPLORATION
GEOLOGIC MODELS
GEOPHYSICS
ORIGIN
QATAR
RESERVOIR FLUIDS
RESERVOIR ROCK
SANDSTONES
SEDIMENTATION
ALKALINE EARTH METAL COMPOUNDS
ASIA
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CARBON COMPOUNDS
CARBONATE MINERALS
CARBONATES
FLUIDS
GEOLOGIC DEPOSITS
GEOLOGY
INDIAN OCEAN
MAGNESIUM CARBONATES
MAGNESIUM COMPOUNDS
MIDDLE EAST
MINERAL RESOURCES
MINERALS
OXYGEN COMPOUNDS
RESOURCES
ROCKS
SEAS
SEDIMENTARY ROCKS
SURFACE WATERS
020200* - Petroleum- Reserves
Geology
& Exploration
030200 - Natural Gas- Reserves
Geology
& Exploration