Statistical and descriptive reports Microphonetic on Talab-e-shadegan cores (Khuzestan Plain)

Description

Introduction According to systematic classification of animals and plants and with respect to uniformity rule of phenomena from past to now which can be compared to life conditions in old organize to modern relatives and with this analysis, we can explain recognition of old environments that total of non-lived paremeters in life frame of organism (organisms) and naturally it is between environment and organisms and much reactions. Because fossils have much amount from ecological condition in geological environments and it is advised for us. We should consider to paleoecology discussion. In these studies that morphology of hard parts in organisms are described according to their operation and each type of change is based on compatibility to environment of organism survive environment and a key for perception of changes from past to now. As it is characterized, important basic for ecology is based on assemblage. This reality that fossils are a symmetry for modern societies and only remnant for main society and it is a basic for paleocecology so if microphonetic information are combined to sedimentology reports and paleo-environment of organisms (paleoecology) is interpreted if sedimentary, chemical and physical parameters have stable changes and relation between species and environment temperature and or relation between number and distribution of organisms to energy amount (food chain). So each type of change in morphology of organisms are derived from change in environment and environmental pollution (Fursichf.t.i. 1995). This reality that fossils are from pair of modern organisms and only remnant of main society is base of paleoecology science so if microphonetic information is combined to sedimentary reports. Microphonetic report is represented by a small sample from activity of marine management in SI in this trend and based on foraminifera studies, present in two taken cores in Talab-e-shadeganand through studies of professor Bateman from Belgium GSI with cooperation of marine geology in GSI. In this survey, two cores are prepared by handy ougerand completely intact with length of 8*9 m and its sedimentary facieses is determined by sedimentologists that it is for correlation and certainty from sedimentary environments and introduced microfacies and some surveys on foraminifera in cores. 1.    Geographical position and geology of Talab-e-shadegan Fresh water in Talab-e-shadegan that its geographical position is shown in figure 1 and it is one of wetlands in Khuzestan plain which is under influence of Jarahi River. Khuzestan plain is to north Persian gulf that its area is regarded from shores of north western from Persian gulf and Imam Khomeini in summer of Khuzestan plain. This desert is formed in Holocene period and it is indicative of last glacial period related to Pliocene (fig 1). 2.    Sample preparation method At first, with doing of field operation which is done in Talab-e-shadegan region and with 2 prepared cores (fig 2), first core (B1) in length of 8m and with geographical position: X = 30˚ 34́ 47" N               Y = 48˚ 43́ 39" Was prepared and cores are transported to lab of sedimentology in marine manegement of GSI. Then some concepts were surveyed from total length of cores with regarding them from top (surface) to low (depth) and based on facies change, color, type, sedimentary type and other evidences is 16 numbers for sub sample. A part of that is as retaining evidences and other its part is for separation of foraminifer graded and analyzed that its stages is as follows: 1-    At first, sample is leached with amount of H2O2 so that organic material results in more cohesion of grains and if it is ruined from study aspect and it is not important. 2-    Then samples are leached to usual water in temperature of 60 inside of oven which is dried. 3-    After drying weighted sample, we should write sample weight that is completely weight of sample. 4-    Weighted samples in shaker screen which is equipped to two screens of 1mm with 65 microns and they are graded. Sedimentary grains are not suitable for these studies and it is bigger than 1mm and less than 63 micron and only grains are between 63 micron and 1 mm (fig 3). 5-    The sample should be weighted inside of oven in 60C which is indicative of total weight of sample again. 6-    After that, based on some experiences accidentally four departure methods are used and two parts of selective sample are as multiplied on each other and for this set, again operation is done in four parts so that amount of sample is as much as needed amount and finally an amount of sample should be separated inside of 300 foraminifera (fig 4). 7-    Selective sample is reweighted (suitable weight) and its volume is calculated by help of ruler, measurement and then volume tools.     3.    Foraminifera study method Preparation sample and division and distributed on Sinipick (fig 5) is poured and with number 300 samples are separated on special vitrites and or slide. Besides separation should be calculated based on their factors: A-    Depth of environment in foraminifera B-    Types of foraminifera C-    Identification of genus and various species A-   Depth of foramina Ferro Environment 1)    Benthic environment: includes all of parts in the sea floor from border to depths and life location in benthic organisms. These organisms are constant or some of them have low displacement and movement. 2)    Pelagic environment: all of waters which embed from shores to depths and plankton organisms live there. These organisms are floating which is submerged in the water and marine flows can be displaced them. It is not said that plankton planktonic organisms for life, relatively calm environments and light penetration locations are preferred with sun light (30-60 m) and less in border parts that location of waves. B-   Types of foraminifera test Totally, test of Foraminifora is composed of materials into follow groups (kh. Khosro Tehrani, 1377): 1.     Pseudochitionous tests 2.     Aqglutineous tests 3.     Calcareous tests A-    Porcelaneous tests B-    Hyaline tests C-    Microgranular tests 4.     Siliceous tests Among introduced test, we pay to their survey that it is in recent in Persian Gulf area and they are: 1.     Sandy or agglutinuous test 2.     Calcareous test: which are considered among them into two hyaline and porcelainous tests. It is necessary that rests of tests are not observed in Persian Gulf (recent). 1.     A sandy or agglutineous test: this type of tests is as external grains and they are joined to secreted materials of pseudochitinous and or calcareous. Selection of external grains depends on present need and material abundance and finally animal life environment. These grains are as quartz grains, heavy minerals, clay and or calcareous grains, test of foraminifera. Radiolers, cocolithus, some fragments from mollusks and finally spicule of sponges. Some of foraminifera show special selection power such as Rhabdomina that it is only as quartzic color grains and or a genus and Marsipella which selects sponge spicule for formation of its test but other group is such as Astrohiza without smallest difference in some objects which are present in sea floor and they are stock to secretive material (fig 6). 2.     Calcareous test: most of foraminifera have a calcareous test. Although, it is in calcareous test of that little percent of Mg CO3, Al, Si but because it is major part of calcareous materials so it is major part of calcareous materials so it is named calcareous test. Calcareous test is seen in Persian gulf in recent and it is as follows: A.    Porcelaineous tests: Porcelaneous test is a calcareous test which has a porcelaneous view and it looks black to dark brown amber against to yellow light. Porcelaneous test is generally amorph and without any pores (fig 7) we can imply to miliolidae family from this type. Hyaline tests Wall of these tests are composed of some small prisms as calcite and its main axis is perpendicular to external surface of the crust. These tests are generally perforated and pores pass flow calcite middle that we can imply to rotalia. C. Calculation and identification of genus and various species Classification and identification of genus and various foraminifera based on complete information from test structural characteristics (chemical composition, test texture), test characteristics ( test shape, chamber lets, order and arrangement of chamberlets and …) are done as various stages in regression (sexual and asexual), type and long life and finally some changes which are occurred in various stages. It is necessary to remind that needed information about organism is mainly based on their hard parts (for example test in foraminifera). It is tried to say that some genus which have abundance majority in Talab-e-shadegan. It is necessary to mention that explains about microscopic . Pesudorotalia Order: Foraminifereida Sub over:Rotaliina Super family : Rotaliace Family: Rotaliidae Genus: Pseudorotalia trocospiral test has seen as umbilical surface to convex intensity and suture lines of chambers in shape of radial and flat area up to little convex and some chambers in shape of spiral near to each other. Test is from hyaline.   Asterorotalia   Order: Foraminifereida Sub over: Rotaliina. Super family : Roraliacea Family: Roraliidae. Genus: Asterorotalia Shape of test is trocospiral bio-convex with hyaline test and chambers are as spiral ones near to each other. Umbilical surface has more convexity around last torsion of teazles torsion.       Elphidium   Order: Foraminifereida Sub over: Rotaliina. Super family : Rotaliacea Family: Elphidiidea Genus: Elphidium Shape of planispiral test (flat torsion) and canals are observed completely. Calcareous and hyaline and has some pores. Umbilica is small and knot and suture line is relief and radial. Cribroelphdium   Order: Foraminifereida Sub ovder: Rotaliina Super family: Rotaliacea Family: Elphidiidea Genus: Cribroelphidium Shape of planispiral test is relief suture line and involute (covered chamber) and canals are seen and hyaline test is in surface of point and perforated test surface and suture lines in radial shape and Umbilica is big and knot and its aperture is composite. Nonionella   Order: Foraminifereida Sub order: Rotaliina Superfanily: Cassidulinacea Family: Nonionidae Genus: Nonionella