modern research physics

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In this research, based on spatial distribution and size of crystals, the role of physical processes affecting formation of the igneous rocks such as kinetics of crystallization (nucleation and growth of crystals), dynamics of magmatic systems (e.g. mixing and convection currents) and equilibrium processes such as textural coarsening are investigated.
To this end, the spatial distribution pattern (SDP) of plagioclase, amphibole and quartz crystals were quantified in the microdiorite-quartz diorites and results were combined with petrography to discuss the factors affecting plagioclase packing arrangements and physical processes operated during formation of these rocks. The study area is located in 120 Km southeast of Birjand. The 8 thin sections of rocks were processed and geometrical features e.g. length, width and centre of 3098 crystals were measured. Then, R values (a descriptive value) were measured using nearest neighbor distance method with BigR and ArcGIS software's and the data were plotted against porosity (modal abundance of other phases in igneous rocks.) Results show that crystals have clustered SDP. The degree of plagioclases clustering is different in sections with change of crystal sizes and shapes. The origin of crystal clusters is likely to involve heterogeneous nucleation, textural coarsening and overgrowth of crystals.

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Introduction and purpose : Chah-Savar-Agha quarry, the quarry which belongs to Neyriz marble quarries complex, is one of the important economical center in the Fars province. In recent years, some slumps and instabilities have occurred in this area and this phenomenon increases the importance of structural studies and investigation of tectonic stress specially insitu stresses. Therefore, the main purpose of this research is the investigation the role of tectonic structures such as joints, fractures, insitu stress phases and effects of them on instabilities of the northern slope.
Method :
By field studies and measurement the geometrical characteristics of the fractures, including dip and dip direction of joints, fillings and the number generations of filling, they are analysed by DIPS5.1 software to achieve the structural analysis and reach to the insitu stress phases.
Results :
According to the results, at least two insitu stress phases are acceptable in the area.
- Releasing stress phase : this stress phase with the South West- North East trend has caused the reactivation of some old joints and creation of some young fractures in the area. The releasing stress phase has been created by rapid extraction from the quarry.
- Local tensional phase :
Field observations have indicated that the Northern slope was creeping in the North East direction and this phenomenon has created the tensional stress phase with the East- West trend in the area and this stress phase has created some vertical fractures with the North-South trend also.
The creep mechanism in the Northern slope has been created by burden of debris which have been accumulated on the top of Northern slope.
Burden of these debris has created the vertical stress that has caused the creep mechanism upon a fracture with N152/50NE identity in the South East Strike.

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The Alut granitoid complex is located in the northwestern part of the Sanandaj–Sirjan zone. This complex comprises three main units i.e. monzogranite to granodiorite bodies (SiO2 = 65–77 wt %) which is widespread throughout the area, a quartz-diorite to tonalite unit (SiO2 = 52–63 wt %) exposed as two stocks and mylonitic granitoid scattered as separate outcrops through the area. NE-SW trending microquartz-diorite and NW-SE trending aplite dykes are also present in this complex. The quartz-diorite to tonalite unit has relatively high CaO,FeO, MgO, Al2O3 and low Rb/Sr, Sr/Y, and (La/Yb)N, which preclude an origin of variably fractionated mantle melts and favour a mafic lower crustal source. Dehydration melting of biotite-bearing metasedimentary sources at relatively low pressures is proposed for the origin of monzogranite to granodiorite unit. Geochemically this complex is metaluminous to slightly peraluminous, typical of I-type granites. It belongs to low K (and high K for some monzogranite samples) calc-alkaline series and displays the geochemical characteristics typical of volcanic arc plutons related to an active continental margin area (e.g. significant Nb, Ti, P and Sr depletion). Based on collected geochemical data, the Alut granitoids originated by partial melting of crustal protoliths having different compositions in a deformed active margin.

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The Pazanan oil field is located in Dezful embayment, 150 km south east of Ahvaz and south east of Aghajari oil field. Aghajari formation has formed surface outcrop and also the Asmari formation with 7 reservoir layers is the main reservoir rock in this oil field. In this research high fractured areas in the Pazanan oil field have been analyzed based on subsurface date and utilization of subsurface analyzes method. It seem to be the Pazanan oil anticline is an asymmetric fold with high dip in south west limb and the middle parts have been distinguished as areas with potential of fractures development with respect to longitudinal Curvature. Geometrics analysis of this structure indicate that south west limb in more parts and north east limb in middle parts have been distinguished as areas with high fractures density. Axial bending (longitudinal) of the Pazanan anticline is because of growth and propagation and combining of separate anticlines shear zone result of strike slip faults motion and old strike slip structures.

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Gabbroic stocks and dykes associated with Ophiolitic Basalts and peridotites are outcropped in the Sawlava town area. Sawlava ophiolite is part of Kurdistan Ophiolitic complex that located in sheared zone between high Zagros and northern Sanandaj-sirjan Zone. This study focused geochemistry and dating of granular and pegmatoid gabbros that due to closing to main recent fault (MRF) some part of them found milonitic fabric. Gabbros have 47.84 to 51.65 percent SiO2 and almost formed from tholeiitic magma. Labradorite plagioclase and diopside and augite clinopyroxens with Mg# of 83.90 to 88.90 respectivly are main minerals of gabbros. Based on geochemical and geotectonic diagrams, gabbros generated from slightly deplete magma which formed in back arc supra-subduction zone. U-Pb dating of zircons presents an average age of 38.3±1.3 Ma for gabbros. Late Eocene age from Sawlava gabbros and similar gabbros bodies related to ophiolites along Zagros suture, could indicate that neo-tethyan ocean closed after Eocene in the Kurdistan region.

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The study area is located to the south, west and north Esfahan province. this research is geochemical and petrographic study of Lower cretaceous dolomites. Five dolomite type have been identified.
The first type is very fine-fine crystalline dolomite formed in near surface conditions and in early stages of diagenesis, in tidal flat to lagoonal environments. The Sr content is high (2537ppm) and Fe (8861ppm) and Mn (852ppm) is low.
The second type is fine-medium-grained, subhedral to euhedral, crystalline dolomites. Compared to the first type, Sr content is lower and Fe and Mn content is higher. This type of dolomites is most likely formed in early burial diagenesis.
The third type is medium-coarse-grained, euhedral and subhedral, crystalline dolomite and show clear rim and cloudy center. Compared to the type1 and type2, this type of dolomite contains higher Fe and Mn and lower Sr. They are likely formed in deeper burial diagenesis and by dolomitization of earlier calcareous deposits or recrystalization of first- and second- type dolomites.
The medium-coarse-grained, crystalline dolomite fill in pores and fractures, and are called "four-type" in this study. This type of dolomite is likely formed during late diagenesis and under conditions of medium pressure and temperatures less than 60-80 °C. In this dolomite values of Fe and Mn increase from the fringes of pores and fractures to the center.
The fifth dolomite type is coarse, crystalline, saddle dolomite filling pores and fractures. This dolomite

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In the northern hillside of Central Alborz, in south Marzanabad, there are outcrops of basic volcanic rocks which attributed to Cretaceous time .In this study, effective processes on evolution of these volcanic rocks are surveyed to add on our knowledge about Mesozoic magmatisim in Central Alborz. Based on petrographical and geochemical studies, south Marzanabad basic rocks could be classified into 2 groups of basalt and andesite basalt. Geochemical diagrams imply that the magma nature is alkaline and generated in intracontinetal extensional environment. Microscopic studies, mineral chemical composition and the observed trends in geochemical diagrams of whole rocks, all are inline with fractional crystallization as a main magmatic process. Fractionation began with crystallization of olivine and pyroxene and minor plagioclase in basalts and continued with crystallization of clinopyroxene and plagioclase in andesite basalt. In addition to petrographical, mineralogical and chemical evidences, the occurrence of fractional crystallization process is confirmed by the geochemical modeling with Melts software which also let us to reconstruct the condition of fractionation process. Based on the fractional crystallization modeling in south Marzanabad basic volcanic rocks, basalts are generated by 40 percent of fractional crystallization from primary magma. Basaltic andesites also produced after the fractionation of basalts, during 70 percent fractional crystallization from the same magma. Olivine thermobarometric studies also confirm the accuracy of data which is obtained by the Melts software.

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Tabriz plain with area of 869 square kilometers is a part of the Urmieh lake's catchment. The purpose of this study is to simulate the behavior of Tabriz aquifer against various stresses and determine the permissible level for the operation of the aquifer. To achieve the above objective the system dynamics simulation method has been used.
In this regard, the required information includes ground water resources data (wells, springs, qanat), sources and consumptions after analysis to eliminate defects was given to the VENSIM PLE+ software, and a dynamic simulation model was developed. Then by define the range of allowed water table fluctuations and the allocation of extracted water under these conditions, the allowable water level and safe yield of the aquifer was determined.
According to the obtained results in the six-year modeling period, the maximum amount of monthly and annual extraction without any damage from the aquifer is 12.70 and 152.45 million cubic meters respectively. The average of minimum and maximum allowable water table level during this period are 1317.35 and 1322.34 meters respectively.

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The granitoid intrusion trending NW-SE, is expose in the East of Zanjan, structurally located in the Alborz - Azarbaijan zone and Tarom sub-zone. Petrographic composition of the intrusion includes a range of monzogranite, quartz-monzonite, quartz-monzodiorite to monzodiorite and in fact shows monzonite series composition. The major rock forming minerals consist of K-feldspar, plagioclase, pyroxene (augite-diopside) and quartz. They show granular, intergranular, microgranular to porphyrytic-microgranular textures. The intrusion has metaliminus high-K calc-alkaline to shoshonitic and I-type affinity. Enclaves of the intrusion have micro-granular mafic and monzodiorite, quartz monzodiorite composition, which are fine-grained than their host rock and have micro-granular porphyritic texture. According to the petrographical and geochemical studies, the magma has originated from partial melting of metasomitised sub-continental lithospheric mantle due to fluids and/or partial melts that originated from subduction edge. According to Harker Diagrams seems that monzodiorite magmas differentiation Leads to monzonite Formation And finally the Crystallization and differentiation are monzogranite. Therefore Crystallization and differentiation are the most important processes controlling rock types in the monzonite series intrusion. Tectonic diagrams indicate a continental margin magmatic arc and syn-to-post collisional intra-arc extensional environment.

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Anbaran inlier is located at the NW of Namin city. In the inlier Pre-Paleozoic roks surrounded by young Eosen and Cretaceouse rocks.To interpret the inlier deformation and its evolution model, geometry as well as kinematic characteristic its major structurs analysed for the first time. For the faults kinematic, indicator, such as slickenside, fault associated folds and S-C structure were used. The results of analysis show that the major structurs of inlier are the Anbaran and RF1 fault at its Norht and South margins.The high angle Anbaran and RF1 faults cause thrusting of the Pre-Paleozoic Biandor and Soltanieh formation in the core of inlier over the Eocen volcanic units and Cretaceouce limeston respectively.This resulted in development of a pop-up structure that form the present morphology of the region .The fault high angele dip, and deposition of Cretaceous sediments on its hanging wall provide evidence for the fault inversion.therefor the RF1 fault is considered as the inverted anbaran fault backthrust.

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In the North of Bam city there were extensive volcanism and outcrops are basic and felsic volcanic rocks that crosscut by various dykes The volcanic rocks have sub alkaline and calc-alkaline to shoshonitic characteristic, however dykes are alkaline and potassic in nature. In the spider diagram all samples show enrichment in the LILEs and depletion and troughs in the HFSs elements that coincide with subduction related and upper crust rocks features. The studied samples represent enrichment in the LREE with various (La/Yb)N ratio and rhyolites show clear trough in Eu. According to geochemical features, studied rocks generated from different sources. Trachy andesy basalts and trachy andesites formed from 1-10% partial melting of metasomatized spinal lherzolite source. Dacitic magma generated from partial melting of mafic source in the lower crust while rhyolites formed from partial melting of metagreywacke source. The olivine basaltic and basaltic dykes generated from less than 1% and 3-5% partial melting of metasomatized garnet- spinel- bearing lherzolitic mantle source, respectively. Eocene volcanism in the Bam area has been occurred during subduction of Neo-Tethys oceanic crust beneath central Iran in the continental volcanic arc tectonic setting.

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Deltas of the most important morphological units are a tremendous effect on agricultural activities, mining, coastal management and etc. Despite appropriate soil and water resources deltas, are influenced by environmental phenomena such as climate change and sea level changes. The effect of these changes will appear on physico-chemical, mineralogical deposits. This study was conducted to analyze the Karkheh delta depositional environments based on the chemical characteristics of ancient sediments. Depositional environments and locations of core were identified using digital data processing, geomorphology mapping and initial visit of the area. The coring was carried out with rotary drilling machine and continuously to a depth of ten meters in jofeir and Rofayeh. Among The cores, 20 samples were selected for mineralogical and chemical tests. Differences in chemical and mineralogical characteristics revealed at least three major discontinuities exist between sedimentary layers to a depth of 10 m. In addition, thickness and type of the sediment are not same conditions and it changes depending on the stability of depositional environments. Increasing of Mg / Ca, magnesium and salinity, and reducing of clay particles, show Sedimentary environments trend is toward dry conditions and high energy environments at depths from 10 to 5 meters. In contrast, the depth of 5 to 4 and 3 to 0 meter this trend towards more humid climate and low energy environments. Therefore, it is concluded that the depositional environment of the Karkheh River delta at the upper Holocene is not constant, and this has led to changes in the delta.

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The Almabulage complex is located in the Sanandaj-Sirjan structural zone, NW of Hamadan. This complex consists of low-grade metamorphic rocks, and two intrusions of felsic and mafic rocks. In this research, we have studied the mafic intrusion. The intrusion has ophitic, subophitic and inter-granular textures and is mainly composed of plagioclase, clinopyroxene, amphibole and minor amounts of K-feldspar, quartz and opaque minerals. Secondary minerals include epidote, chlorite and amphiboles formed in the rim of clinopyroxene. Clinopyroxene is of augite type, amphibole is tschermakite, plagioclase is in the range of andesine-labradorite, k-feldspar is anorthoclase and the opaque mineral is ilmenite. According to the bulk rock geochemistry and mineral chemistry of clinopyroxene, the mafic intrusion of the Almabulage complex has been crystallized from a calc-alkaline magma and is related to subduction area. The element Nb displays distinctive negative anomalies compared to the primitive mantle, which can suggest subduction-related magmatism. Emplacement temperatures and pressure of mafic rocks shown by pyroxene-amphibole thermometer and amphibole barometer indicate temperature and pressure ranges of 750 to 900 °C and 6 to 7 kbar, respectively.
Based on Sm/Yb and La/Sm rations, the parental melt of the mafic rocks of the Almabulage complex, derived from partial melting of garnet–spinel lherzolite. According to the bulk rock geochemistry and mineral chemistry of mafic rocks, the rocks formed in a subduction area during Late Jurassic-Early Cretaceous before the Neo-Tethys closure in Sanandaj- Sirjan zone.

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In this research, changes in structural geometry of thrusting of the Aghajari anticline on the Marun anticline in Dezful Embayment (SW Iran) have been studied based on seismic reflection data. These two anticlines have a NW –SE trends and thrusting of the Aghajari anticline on the Marun anticline is located in North of the study area. The Marun anticline with visible plunge is forming in the south of study area and 4 and 5 seismic profiles, and most of deformation is concentrated in Aghajari anticline. Also, Marun anticline has formed in the middle of the study area, but thrusts not formed in this part of anticline and maximum thrusting of Aghajari anticline on the Marun anticline is visible. There is a shallow thrust in south limb of two anticlines in northern part and an upper thrust from Gachsaran formation exposed from progressive deformation and finally a shallow thrust propagate to surface in both anticlines in the end of NW parts of study area and back thrusts separate from main shallow thrust in two anticlines. But unlike the Aghajari anticline, an upper thrust from Gachsaran formation propagates to surface with progressive deformation in the Marun anticline showing low depth of the Marun anticline.

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The various species of Alveolina for biostratigraphy of Eocene sedimentary rocks are very important. In this research, the species of Alveolina  are reported for the first time in three cross sections: Chalonak, Kalaterood and East Beinabad. These sections are attributes to Early- Middle Eocene age. The 55 samples collected from Chalonak section and the thickness is reached to 245 m. In this section, four biozones are distinguished. They are following: Alveolina globula-Alveolina solida interval range zone, Alveolina solida-A .globosa interval range zone, Alveolina globusa total range  zone and  Alveolina aragonesis  total range zone. On the basis of index fossils such as  Alveolinana  avellana, A. aragonensis,A. globula, A. leupoldi, A. globusa, A. elliptica nutalli, A. rotundata, A. corbarica, A.solida, which are existing in these biozones, the age of this section is attributed to Early Eocene. Of course two species of Nummulites (Nummulites globulus, N. atacicus) and Cuvilierina valensis are determined in Chalonak section. The 80 samples are collected from Kalaterood section and the thickness is reached to 242 m. In this section, four biozones are distinguished. They are following: Alveolina solida- A. globosa interval range zone, Alveolina globosa total range zone, Alveolina aragonensis-A. canavarii interval range zone and A. canavarii total range zone. The several index fossils are found in this section following: Alveolina aragonensis, A. decipiens, A. Avellana, A. laxa, A. pasticillata, A. canavari, A . globosa and A. solida. The age of this section is Early Eocene.  The 150 samples are collected from East Binabad section and the thickness is reached to 900 m. In this section, four biozones are presented. They are Glomalveolina   lepidula – Alveolina solida interval rage zone. Alveolina elliptica nutali- Alveolina corbarica interval range zone, Alveolina corbarica total range zone and Alveolina ruetimeyeri-Alveolina levantina assemblage zone. There are several index fossils such as Alveolina corbarica, A. elliptica nuttalli, A.levantina,  A. roetimeyeri  and  A. decipiens, Glomalveolina lepidula. The age of this section is early Eocene.

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Marziyan granitic pluton is one of the numerous intrusive bodies in Sanandaj-Sirjan structural zone. The pluton is composed of locogranite, granite and granodiorite and its contact metamorphic rocks are consisting of cordierite and andalusite schist. Tourmaline and garnet bearing locogranite, aplite, pegmatite, mylonite and injected migmatite are exposed in the metamorphic halo. The major minerals include quartz, plagioclase, K-feldspar, biotite as well as muscovite, tourmaline and garnet. Structural studies indicate the presence of shear zones, especially in the southeastern parts with NNW-SSE trend. Four types of microstructures are present in the region 1) magmatic microstructures, 2) high temperature solid state microstructure, 3) low temperature solid state microstructure and 4) sub-mylonitic and mylonitic microstructure. All rocks of the region have been subjected to shear deformation which led the formation of S-C foliations and other sense of shear markers. The presence of asymmetric porphyroclasts and porphyroblast, biotite and feldspar kink bands, mica-fish mica and andalusite and domino and boudinaged structures of feldspar and tourmaline are evidences of ductile deformation in a contractional and dextral shear regime. All evidences indicate that high temperature solid state zones in greenschist facies to lower amphibolite conditions (300-500°C) have formed simultaneously with emplacement of granitic bodies. Low temperature solid state, sub-mylonitic and mylonitic zones developed following the emplacement of granitic bodies.

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Aliabad Damagh region in southern Hamadan, is located NW of Sanandaj Sirjan Zone. In this region, different metamorphic rocks with a variety of fabric elements are exposed. In this research, metamorphic rocks were investigated based on the microfabric and temperature. In the area deformation occurred along the temperature variations path. Three generations of foliation and four deformation phases are present in the region. Porphyroblasts growth in foliation and microfabric evidence reveal that deformation began during regional metamorphism, while mica and chlorite crystallized as post tectonic minerals compare to S₃ during retrograde metamorphism. The highest grade of this metamorphism is green schist to amphibolite facies.
Deformation elements in granite mylonite and metamorphic rocks in Aliabad Damagh region imply occurrence of regional metamorphism followed by a dynamic metamorphism which cause a widespread ductile shear zone. Deformation elements in carbonate mylonites, confirm the presence of a right lateral shear zone. Based on calcite twinning in mylonitize marbles the temperature of dynamic metamorphism is higher than 200 ˚C. Based on the effect of temperature on lithology, fabric and strain rate, the shear zone in Aliabad Damagh region is ductile to brittle.  

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Baladeh-Kojour earthquake of May 28^th, 2004 is one of the largest earthquakes in vicinity of Tehran, occurred in the northern part of the Alborz range. In this research, spatial variation of fractal parameters has been studied to estimate the seismic pattern of the study area. In order to draw the spatial variation maps, b-value, correlation dimension of epicentral and temporal distribution of earthquakes, D_e and D_t have been calculated for the data sets of before and after the mainshock, separately. The results show that before the earthquake, these parameters have low values in the eastern side of the mainshock epicenter. It seems that these low values before the earthquake may arise due to clusters of events with larger magnitude and small events after it. Seismic rate has decreased in the surroundings of the mainshock (seismic quiescence). After the mainshock, the lowest values of b-value and D_t is seen in the epicentral and western part of the mainshock. These low values are due to aftershock clustering and stress release, took placed just after the mainshock and during the aftershock sequence. Intensity increasing is observed in the shake map of earthquake. The D_e parameter is low after the mainshock occurrence. Low b-value and high D_e indicate high level of seismic activity in the region. The obtained results show the fractal parameters sensitivity to spatial and temporal clustering of earthquakes. Therefore, these parameters can be used as an indicator for seismic precursory patterns of major earthquakes.

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The present study aimed at identifying the nitrate transport in the groundwater of Lenjanat plain, Isfahan. Nitrate concentrations were measured seasonally and groundwater flow was modeled for nitrate transport simulation using MODFLOW and MT3DMS codes. The nitrate concentrations were compared with the human and livestock drinking water and irrigation water standards. The results show that nitrate concentrations are higher than the guidelines limits in groundwaters. The flow modeling reveals that the groundwater flow system of the study aquifer has been influenced by the aquifer hydrogeological characteristics. The falling watertable and reduce aquifer storage are due to the anthropogenic stresses on flow system. The transport model calibration and sensitivity analysis shows that nitrate leaching from agricultural land, first–order irreversible rate reaction, effective porosity and precipitation are the major factors affecting the entry and retention of nitrate in Lenjanat groundwater. Denitrification rate in the aquifer has been decreased due to high concentration of dissolved oxygen in groundwater and low extent of organic carbon. Half-life of nitrate in Lenjanat aquifer is more than 2.5 years. Nitrate transport in the aquifer is mainly by convection. Considering the calculated mass with transport model, the nitrogen leaching to groundwater of study area is 108 kg N ha^-1 yr^-1.

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Gabbroic bodies with NW-SE trend outcropped in the southwest of Sahneh in the north of Gamassiab River, W. Iran are part of Zagros ophiolite . This complex is separated from the other geological units by deep faults and cut by pyroxenitic dikes. The field evidences, petrographic, geochemical and mineral paragenesis of these rocks are completely different from the fresh and un-altered gabbroic rocks. Furthermore the high ratios of ¹⁴³Nd/¹⁴⁴Nd (0.512945-0.513021) and low ratios of ⁸⁷Sr/⁸⁶Sr (0.70334-0.70656) indicate the sub-oceanic depleted mantle source for the origin of these rocks. Low variation of ¹⁴³Nd/¹⁴⁴Nd ratios, increasing of ⁸⁷Sr/⁸⁶Sr ratios, decreasing of SiO₂ and increasing of CaO and Al₂O₃ mainly concludes the high reaction of gabbroic rocks with seawater. The pargenetic assemblages of altered gabbros are grossular/hydrogrossular, anderadite, epidote, idocrase (vesuvianite) and diopside. The mineral paragenesis reveals that the rodingitization was occurred by reaction of gabbroic bodies with high alkali water at a shallow depth