*6.1.4 FA4, pelagic/hemipelagic basin plane*

Hemipelagic/pelagic basin plain sediments of the Kolosh formation are very monotonous sequences of alternating thin sandstone, siltstone, mudstone, and hemipelagic silicified mudstones. These beds are associated with numerous intercalations of thin turbidity

#### **Figure 3.**

*Depositional model of the Kolosh Formation discusses the slope and basin plan with anatomy of submarine fan and lithofacies types. Ta-b-c-d-e are subdivisions of Bouma turbidity cycle.*

*Abnormal Ophiolite (Olivine/Pyroxene Rich) Sandstone NE Iraq: An Approach to the Origin… DOI: http://dx.doi.org/10.5772/intechopen.108333*

#### **Figure 4.**

*Schematic anatomy model shows subdivisions of the submarine fan and Bouma turbidity cycle; A. Bouma cycles subdivisions, Ta to Te e.g. Ta= pebbly to coarse-grained sandstone, Tb= laminated sandstone, Tc= cross-bedded sandstone, Td=very fine sandstone to siltstone, Te=mudstone/shale and position in the fan. And subdivisions of submarine fan; 1) canyon, 2) Mobile channels with wings, 3) fan fringe and abyssal plan B. Facies types in the slope and submarine fan; slump deposits, debris flows and deep sea floor cf. abyssal plain (adopted from Mutti [16]).*

lime mud beds and related slump units, which belong to quite distinct depositional settings [16, 30, 31, 42]. The carbonate mud/marl beds are derived from tectonically unstable flanking platforms (cf. around island arc) and include a variety of fine-grained distal turbidites facies rich in planktonic foraminifera and radiolarian fossils.

The basin plain sediments of the Kolosh formation are characterized by the following features:

The surfaces of the beds are even parallel regardless of the extent of exposures and turbidite beds are missing the base of Bouma cycles with predominant Tc-e divisions. The sandy and/or silty division of the turbidite beds are of thin parallel laminae (Td-division), which grades transitionally into turbiditic mudstone (Te-division) (**Figures 3** and **4**). Typically, the small-scale cross/wavy laminae of the current-ripple division (Tc) display low to very low angles and occur in well-developed climbing patterns. The basal portion (Tc) is fine to very fine sandstones. The turbidite beds are regularly alternating with thinner and bioturbated hemipelagic beds. Moreover, these beds contain distinctive assemblages of indicative benthic foraminifera of water depths in the range of 600–2000 m, as well as planktonic types [16].
