This facies consists of horizontally laminated fine-grained sandstones. This section, with 6 m thickness, is located in Darin section. This section represents semi-rounded, moderately sorted and semi-mature grains in size of 0.125 mm. These sandstones enjoy quartz arenite petrofacies (Figures 2(a)-(c)).

This facies contains flat diagonal classification and enjoys high frequency in the upper parts of this section. Diagonal layers have an angle between 10 to 13 degrees and can be found in either simply diagonal or mixed forms, accounting for deposits in aqueous environments with unidirectional and bidirectional flows [4] . The size

of grains is 0.3 to 2 mm. These sandstones comprise quartz arenite petrofacies (Figures 2(a)-(c)).

Sandstone facies (Sh), resulting from low and high speeds of water flow, includes flat parallel lamination as well as medium-fine grains, and is converted into other sandstone and mudstone facies [5] [6] . Regarding the grain size and the relationship between horizontal lamination and high-energy flows in fine-grain sandstones, one can attribute the formation of this facies to the high speed of water flow [7] . This facies is likely to be formed in the beach environment or in channel.

Sandstone facies (Sp) enjoys a flat diagonal classification, formed at low speed of water flow and due to the movement of ripples and two-dimensional megaripples [8] . Due to the diagonal floors, the facies Sp is developed in the intertidal zone while large-scale diagonal floors, affected by bars are formed in tidal channels [9] .

Beach facies indicate relatively high energy conditions in this sub-environment. Meanwhile, the presence of the iron oxide veins can be due to the large amount of solved oxygen, proving the shallowness of this environment. Therefore, one can conclude that this microfacies belongs to a sandy beach [10] [11] . Moreover, mature petrofacies to supermature quartzarenite confirm the high tidal current regimes [12] .

This microfacies is observed in grey thin-to-thick bedded limestones of Chili Formation. This microfacies mostly enjoys mudstone matrix and lacks compaction and pressure dissolution. It is noteworthy that only Bird’s-eye and Fenestral fabric pores and biological disturbance are recognized there and no other allochem was found [13] . Fenestral pores are usually found in all mudstones and used to determine the amount of porosity [14] . The mentioned conditions suggest that this microfacies is deposited in the upper part of lower intertidal sub-en- vironment (Figure 3).

Facies associated with upper intertidal zone are formed in dry and hot weather conditions.

Mudstone with fenestral fabric as well as biological disturbance, evaporative minerals and fenestral fabric pores suggest the deposition of microfacies in upper intertidal zone [15] . Lack of biological varieties in mudstone facies indicates lack of appropriate conditions for organisms’ growth [11] [16] [17] . Due to the intermediate environment of the facies Formation, their deposits are moved out of water regularly and irregularly and show certain characteristics. These types of evaporative minerals can be found in upper tidal zone of Texas and southern cost of Mediterranean [18] -[20] . The presence of these minerals indicates a medium-heat temperature of over 22 degree C and seasonal temperature of 35 degree C [4] . These facies resemble the carbonates of southern coasts of Persian Gulf [13] [21] . Intertidal environment facies mostly involve fenestral fabric and micro foraminifera [22] .

The most important and frequent allochem of this microfacies is pelecypoda (40%) with size of 1 mm. Also, the pellet found in these samples (15% - 25%) enjoys good sorting and roundness with size of 0.1 mm and is located in micrite ground. This microfacies belongs to dark grey thick bedded limestones (Figure 4(a)).

In this microfacies, intraclast (35%) has weak sorting but good roundness with size of 2 mm. Also, the pellet found in these samples (10%) enjoys weak sorting and semi-roundness with size of 0.1 mm. This microfacies is located in dark grey thin bedded limestones (Figure 4(b)).

Benthic foraminifer observed in this microfacies accounts for 60% of total samples and is of Globivalvulina-Staffellida type. Its grain size is 0.7 mm and enjoys weak sorting and roundness. The conditions in this microfacies are similar to those in microfacies C2 and are formed in the same environmental conditions, except that the Formation environment of microfacies C3 includes more energy. It is formed in limestones with grey shale and marl layers (Figure 4(c)).

This facies, consisting of skeletal particles such as benthic foraminifera which includes (Globivalvulina, Tuberitina, Earlindia. sp.), indicate 10% frequency and have the size of 0.2 mm. And pellet (35%) enjoys weak sorting and semi-roundness and its grains size is 0.1 mm. This microfacies can be found in grain thin-bedded nodular limestones and suggests a semi-restricted lagoon environment (Figure 4(d)).

This microfacies contains gastropoda particles (35%) and its size is 2 mm. Moreover, 20% intraclast and 5% echinoderm with weak sorting and roundness, and size of 0.3 mm are also observed in this microfacies. It is formed in limestones with grey shale and marl layers (Figure 4(e)).

This microfacies involve 45% spindle-shaped fusulinid in 3 mm size and 7% benthic foraminifera (of Dekerella

type) with weak sorting. This microfacies is formed in grey thin-bedded limestones (Figure 4(f)).

Some common characteristics among the microfacies of this group are the presence of lime between main grains and the presence of bioclasts, resulted from lagoon organisms, capable of living in a restricted or semi-restricted condition. The first common characteristic is a cause of tranquility in their Formation environment but the second one indicates high salinity in depositional environment of this group. The difference between microfacies of this group is due to the fabric type and their grain size [11] .

Small and large algaes and foraminifers are observed in facies of euphotic zone, where the water depth and nutrients are low [23] -[25] .

Wackstone/packstone facies including foraminifera are formed in lagoon environment and foraminifera with porsolanuz wall are also formed in hypersaline environment [11] [17] [26] [27] . Another salient characteristic of this facies is biological disturbance, resulted from activity of infauna and points to the deposition of microfacies in a relatively calm environment with restricted water circulation and below the wave effect line. These microfacies are formed in shallower parts of lagoon under the low ambient conditions [4] [17] . The presence of microsteolites in this facies is due to lack of primary cementation, resulted from organisms’ activities [28] . These microfacies are formed in the deeper parts of lagoon under a low ambient condition. Since nutrients are limited in such conditions, sediment eaters’ activities rise and activities of various burrows including distinct and indistinct ones are resulted from activities of such organisms [29] . Such organisms mostly continue their life through grazing [30] . The fundamental characteristic of some lagoon facies is high percentage of pelloid, gastropoda, benthic foraminifera and intraclastics. Other elements including pelecypoda are also found in this facies, the presence of pelloid and gatropoda point to the Formation of this facies in shallower part of lagoon environment.

The most important allochem of this microfacies consists of echinoderm particles (50% - 60%) and is more frequent than other fossil fragments and its size ranges from 1 to 2 mm. Echinoderm fragments are place in sparite cement ground and enjoys microstilolite in their contact level. This facies belongs to thick bedded limestones with grey marl layers. These conditions reveal that this facies is formed in an environment with high energy (Figure 5(a)).

The allochems of this microfacies are of bryozoan type (70%) and highly rounded. Its size is 3 mm. Moreover, 5% echinoderm, 2% Ecinid, 2% benthic foraminifera, are seen there, among which benthic foraminifera contains Golobivalvulina. This facies belongs to thick bedded limestones with grey marl layers (Figure 5(b)).

This microfacies, consisted of low Permian pesodufusulinid, covers 80% of the facies and its size is 5 mm. This facies belongs to grey mid-to-thick bedded nodular limestones (Figure 5(c)).

This facies contains 30% echinoderm with 0.5 mm size, 15% intraclast with 0.2 mm size and rounded and sorted quartz in sand size. This facies belongs to grey thin-to-mid bedded limestones (Figure 5(d)).

This facies is covered by 40% ooid, 10% pellet and 5% bryozoa. The core of ooid is made of echinoderm, bryozoan and benthic fram. Moreover, the presence of twin elliptical ooids and lumps (some ooids in one) is of great importance. In this microfacies, due to the high-energy conditions, the ooid fragments are mostly spherical and elliptical and poorly sorted. This microfacies is mostly made of ooids of 0.2 - 0.5 mm. This facies is formed in a shoal submarine ridge due to the presence of ooids, crenoids rounded in the sparite ground and sorting of allochem. It belongs to dark grey and brown thin-bedded sandy limestones (Figure 5(e)).

The common characteristics of all bar facies is the lack of lime matrix among bar facies grains. This refers to the high rate of energy in their Formation environment. In other words, these facies are formed above wave effect line.

Ooid, bioclast and shoal bars facies are developed in platform margin sub-environment. Skeletal particles of organisms such as bryozoa and echinoderm are observed in slope zone and can lead to development of washed sand deposits in shoal and bars [11] [31] . This sub-environment separates lagoon sub-environment from open sea. The presence of sparite cement, ooids abundance, mid-to-well sorting and lack of lime in facies confirm an environment with high energy. Today, the same facies can be found in southern coasts of Persian Gulf and Bahamas at the depth of less than 5 m.

Ooids abundance and lack of mud matrix indicate high energy in depositional environment, in which waves and currents transfer the carbonates. Such depositions point to washed sand forming carbonate bars. The skeletal particles forming these sands are usually originated from open sea [11] .

Lack of micrite is the main cause of high energy in theses facies. Large size of these particles and their relative sorting are among factors determining high energy in this facies. In addition, small amount of Isopachous cement implies high deposit accumulation rate [32] . Lack of gravity cement is a sign of not moving out of water [11] [33] . One of the characteristics of some microfacies is the presence of oncoide, accounting for higher rate of energy in the environment than that of other facies.

This microfacies, involving muddy ground and lacking allochem, indicate a relatively high depth during the deposition in this microfacies. This microfacies is formed in grey mid-to-thin bedded nodular limestones (Figure 6(a)).

15% spiculite and 10% radiolaria in 0.1 - 0.2 mm are found in this microfacies. Spiculite is dispersed and no particular orientation is seen, and is mostly single-axis. Spiculite together with radiolarian in amuddy ground are among the most important components of deep and low-energy environment of open sea (Figure 6(b)).

30% fusulinid of 1 - 2 mm size and 10% echinoderm of 1 mm are observed in this microfacies. A small amount

of plleoid and intraclast is seen as well. This microfacies belongs to grey thin-bedded limestones (Figure 6(c)).

The presence of intergranular muddy matrix [1] , the abundance of spiculitic and radiolarian [17] , as well as the presence of echinoderm [11] . point to the formation of sediments in a low-energy and calm environment like open marine [11] [17] [34] . Regarding the presence of stenohline species such as echinoderm, these microfacies are formed in a moderately saline environment like open marine [17] [35] .