Open AccessLithofacies Attributes of a Transgressive Carbonate System : The Middle Eocence Seeb Formation, Al Khoud Area, Muscat, Oman
Author(s) -
Osman Salad Hersi,
Abdulrahman Alharthy
Publication year - 2010
Publication title -
maǧallaẗ ǧāmiʿaẗ al-sulṭān qābūs li-l-ʿulūm/sultan qaboos university journal for science
Language(s) - English
Resource type - Journals
eISSN - 2414-536X
pISSN - 2308-3921
DOI - 10.24200/squjs.vol15iss0pp41-54
Subject(s) - geology , shoal , wackestone , grainstone , carbonate , transgressive , sedimentary rock , sedimentary depositional environment , sedimentary structures , sedimentology , foraminifera , deposition (geology) , paleontology , intertidal zone , geomorphology , geochemistry , carbonate rock , sediment , oceanography , benthic zone , structural basin , materials science , metallurgy
The Seeb Formation (Middle Eocene) is an about 600 m thick transgressive carbonate succession deposited in the Batina and Muscat coastal region of Oman. The formation consists of five informal, but distinct units, and their stacking architecture suggests a deepening-upward, shallow marine depositional setting. Unit I is characterized by cross-bedded, sandy, bioclastic packstones to grainstones deposited in a high energy beach-to-intertidal environment. Unit II consists of indistinctly bedded, nodular, bioclastic (mainly larger foraminifera) packstones and wackestones deposited in a logoonal lagoonal environment. Unit III is defined by medium to thickly bedded, bioclastic packestones to grainstones and subordinate, laterally confined conglomerates. Prominent sedimentary structures in Unit III include hummocky and swaly cross-stratificiation, erosional surfaces, dewatering-induced deformations and laterally amalgamating beds. This unit represents sub-tidal sand shoals deposited in a storm-dominated shelf (between the fair-weather wave-base and storm-base). Unit IV is extensively burrowed, nodular, bioclastic wackestone to rudstone which is similar to Unit II in many aspects. Unit IV was deposited on the basinward side of the Unit III sand shoals below the reach of the storm-generated waves and currents. The uppermost Unit V is characterized by poorly-cemented bioclastic (large foraminiferal) rudstones with clay and silt-size quartz matrix. Bioclasts are generally intact with no apparent reworking. Deposition of Unit V is also envisaged as a low-energy, outershelf environment.