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The purpose of this study is to describe fishermen's and managers' current awareness of International Maritime Organization (IMO) biofouling guidelines to improve biofouling management on all fishing vessel types in the northern Persian Gulf. A total of 234 in-depth and semi-structured interviews were conducted face-to-face with fishermen and managers using a random sampling technique from February to November 2021. Analyses of data indicated that the majority of industrial fishermen (87%) and all of managers were aware of the IMO biofouling guidelines, but traditional fishermen had a low level of awareness (38%) and they had also many problems such as increased cost, lack of training courses, lack of sufficient facilities for implementation of IMO biofouling guidelines. For industrial fishermen, literacy was a most effective variable on awareness of IMO guidelines (p ˂ 0.05, r = 1.62). As regulations to prevent invasions and the accumulation of biofouling in fishing gear and fleets, biofouling should be managed and evaluated, and also training should be provided to fishermen to clean the biofouling of fishing gear and fleets in accordance with IMO guidelines, as well as more monitoring by managers, environmentalists, the government, and policymakers. [ABSTRACT FROM AUTHOR]

The taxonomy of oysters along the northern coasts of the Persian Gulf and the Gulf of Oman is not well recognized. We present a phylogenetic analysis of oyster species in these regions. We combined morphological and molecular techniques to obtain the identity of oysters to the lowest taxonomic levels. Analysis of partial nucleotide sequences from mitochondrial cytochrome c oxidase subunit I (COI) was used for the phylogenetic evaluation. Based on our findings, Iranian samples nested within the genus Saccostrea and belonged to Saccostrea mordax and Saccostrea palmula clades. The shell morphology of the studied samples was variable, as in other rock oyster species. The examination of morphological features was in line with the molecular outcomes, but despite some similarities, Iranian S. palmula had well-developed and elongated chomata. The results also showed that S. mordax and S. palmula possessed significant relative abundance as dominant oysters in the Persian Gulf and the Gulf of Oman, respectively. Phylogenetic analysis revealed that Iranian samples of S. palmula formed a separate subclade from the Gulf of California and Panama samples, with large genetic distances (6–7%). Iranian specimens differed morphologically and genetically, suggesting that they could be a new species, although more research is needed. [ABSTRACT FROM AUTHOR]

In a comprehensive geochemical study, the genetic relationships among 14 samples of gas condensates from the Persian Gulf were investigated for the purpose of evaluating the respective source rocks in terms of both age and sedimentary paleoenvironment. Chemometric analysis was used for categorization and determination of a certitude range to determine the genetic type of the condensate families in the studied basin. The samples were collected from Late Permian – Triassic reservoirs (Dalan and Kangan formations) located in 6 gasfields (gas condensate) hosting some of Iran's most important gas/gas condensate reserves. Obtained by gas chromatography‐mass spectrometry (GC‐MS), a total of 16 biomarker parameters (10 maturity‐related parameters and 6 sedimentary environment‐related parameters) were used to evaluate the samples in terms of thermal maturity (and hence their positions in the maturity chart), the sedimentary environment of the source rock and the lithology. Application of Hierarchical Clustering Analysis (HCA) and Principal Component Analysis (PCA) to the collected data led to the categorization of the samples into three main genetic groups, I–III. Groups I and III were found to be located in the east and the west of the Persian Gulf, respectively, while Group II was developed between the two other groups. [ABSTRACT FROM AUTHOR]

In this study, sodium alginate was extracted from Sargassum algae, collected from coastal waters of Bushehr, Persian Gulf, Iran and used as a stabilizing and wrapping agent for CuO nanoparticles. The synthesized nanocomposite was characterized by some spectroscopic and microscopic techniques, such as IR, XRD, Uv–vis, BET, BJH, zeta potential, SEM, TEM, HR-TEM, and XPS. The antibacterial effects of the CuO–alginate nanocomposite against some bacteria, isolated from a burn wound, were evaluated. The results showed that this nanocomposite had better antibacterial effects than its components on Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 12600, Streptococcus pyogenes ATCC 19615, and Staphylococcus epidermidis ATCC 49461. Among these, Staphylococcus aureus ATCC 12600 was the most sensitive one to this nanocomposite, with the lowest minimum inhibitory concentration (2.08 mg mL−1) observed. Moreover, the synthesized nanocomposite showed good catalytic activity in the oxidative coupling of carboxylic acids with N,N-dialkylformamides toward the synthesis of amides. [ABSTRACT FROM AUTHOR]

Oysters are widespread throughout the intertidal regions, and accurate identification and monitoring of their ecological status are still difficult due to their high level of plasticity. Anthropogenic activities facilitate oyster dispersal to new habitats through the shipping and elimination of existing barriers. In this study, a combination of morphological and molecular techniques was used to clarify the identity of an oyster species occurring along the Iranian coast of the Persian Gulf. Specimens were collected from the jetties of the ports and the rocky shores along the northern Persian Gulf. Oyster identification was carried out to the lowest possible taxonomic level based on shell morphology. The phylogenetic analysis was done using the cytochrome c oxidase subunit 1 (COI) fragments. Morphological results confirmed that studied samples belong to the genus Crassostrea and showed close to the Vietnamese (Crassostrea markushuberi) species. Molecular analysis reveals that species are a sister species to a clade containing Crassostrea zhanjiangensis and Crassostrea talonata. According to the relatively high genetic distances and lack of similarity in shell characteristics, the species is considered as distant sister species of C. zhanjiangensis and C. talonata. The results showed a non-native small size of oyster in the northern Persian Gulf, which might be a new species. The relative abundance of this species in the introduced location (Imam Khomeini port) may be linked to the high adaptation capability to the new environment. [ABSTRACT FROM AUTHOR]

A new species of the laelapid mite genus Gaeolaelaps Evans & Till, G. tuberculatussp. nov., is described from female specimens collected in soil and rotten leaves under citrus trees in Mazandaran province, northern Iran. Supplementary information on G. deinos (Zeman) is presented. Gaeolaelaps schusteri (Hirschmann) is redescribed based on the type specimens as well as additional specimens collected from the littoral zone of mangrove forests in Qeshm Island, in the eastern part of the Persian Gulf, southern Iran. [ABSTRACT FROM AUTHOR]

Rock typing and flow unit detection are more challenging in clastic reservoirs with a uniform pore system. An integrated workflow based on well logs, inverted seismic data and rock physics models is proposed and developed to address such challenges. The proposed workflow supplies a plausible reservoir model for further investigation and adds extra information. Then, this workflow has been implemented in order to define different rock types and flow units in an oilfield in the Persian Gulf, where some of these difficulties have been observed. Here, rock physics models have the leading role in our proposed workflow by providing a diagnostic framework in which we successfully differentiate three rock types with variant characteristics on the given wells. Furthermore, permeability and porosity are calculated using the available rock physics models to define several flow units. Then, we extend our investigation to the entire reservoir by means of simultaneous inversion and rock physics models. The outcomes of the study suggest that in sediments with homogeneous pore size distribution, other reservoir properties such as shale content and cementation (which have distinct effects on the elastic domain) can be used to identify rock types and flow units. These reservoir properties have more physical insights for modelling purposes and can be distinguished on seismic cube using proper rock physics models. The results illustrate that the studied reservoir mainly consists of rock type B, which is unconsolidated sands and has the characteristics of a reservoir for subsequent fluid flow unit analysis. In this regard, rock type B has been divided into six fluid units in which the first detected flow unit is considered as the cleanest unit and has the highest reservoir process speed about 4800 to 5000 mD. Here, reservoir quality decreases from flow unit 1 to flow unit 6. [ABSTRACT FROM AUTHOR]

• Pristurus rupestris iranicus is assigned to candidate Species 3 of P. r. rupestris that was previously recorded from Arabia. • Iranian P. rupestris and candidate Species 3 form a single population. • P. r. iranicus should be synonymized with P. r. rupestris. • It is speculated that P. rupestris may have colonized Iran from Oman. Pristurus rupestris is a member of Semaphore geckos with a wide distribution range. Recently, 14 candidate species of P. rupestris rupestris have been identified in the Hajar Mountains (Arabia), yet the knowledge on the Iranian counterparts is limited. The present study elucidates the phylogenetic position of the Iranian P. rupestris and investigates the hypothesis on its historical colonization from Oman to Iran and the associated islands. Therefore, 20 Iranian specimens along with 115 individuals from Oman were examined using two mitochondrial genes including the Cytochrome b and the 12S ribosomal RNA. The molecular phylogenetic analyses revealed that the individuals collected from Iran are well nested within the candidate Species 3 of P. r. rupestris , demonstrating a single population with high gene flow. Additionally, the molecular analyses showed that the genetic diversity within the Iranian Blanford's Semaphore geckos is low and that the candidate Species 3 experienced a recent expansion approximately 17 thousand years ago (Kya). The historical demographic analyses (BSP) showed a mild increase in the effective population size between 15–20 Kya. These time estimations coincide with the Last Glacial Maximum, when the Persian Gulf was almost dry, reinforcing the hypothesis that the species might have colonized southern Iran from Oman through the Persian Gulf. In addition, we propose P. r. iranicus to be synonymized with P. r. rupestris. [ABSTRACT FROM AUTHOR]

The Coastal Fars and the Iranian part of the Persian Gulf are one of the largest natural gas provinces in Iran. More than 90 percent of the natural gases in these areas are found in Dalan (Upper Permian) and Kangan (Lower Triassic) carbonate rocks. In order to determine the origin of the natural gas in Iranian sector of Persian Gulf and Coastal Fars area, we collated 23 gas samples (7 samples from Kangan Fm. 12 samples from Upper Dalan and 4 samples from Lower Dalan) from 12 gas fields in the study area and analyzed chemical and isotopic composition. Based on molecular composition and isotope data, gas samples in the study area have the thermogenic origin. In the lower part of Dalan Formation, evidence of secondary process like thermochemical reduction of sulfate (TSR) is seen. The main part of hydrocarbon gases was generated during secondary cracking of paleo-oil in these reservoirs. Based on this study, lower Silurian organic-rich shales (Sarchahan Formation) with the 1–1.8 vitrinite reflectance, is the main source for the natural gas of southern Iran. [ABSTRACT FROM AUTHOR]

According to elemental analysis practiced on 47 samples from different locations in Persian Gulf, pelagic carbonate rocks constitute the dominant source rock while an increase is observed in amounts of evaporative facies in eastern regions and shale facies in southern regions. The isotope analysis reveals that there are three groups of source rocks in Persian Gulf; first are Asmari layers with an age of 95–97 million years, second is reservoir layer of Sarvak with an age of 105–107 million years estimated for its source rock, and third are numerous reservoir layers with source rock ages between 138 and 145 million years. [ABSTRACT FROM AUTHOR]

Shale and clay minerals as common constitute in the sandstones can be distributed in various scenarios which in turn can result in different reservoir and elastic properties. A new classification with distinct subclasses for clay distribution has been proposed based on the plausible configuration of shale/clay particles within the sandstone reservoirs. These subclasses give more quantitative insights into laminated, structural and dispersed clay scenarios by taking into account more details of the shale and clay microstructures. Some rock physics-based workflows were proposed and implemented on a real dataset to validate the given strategies to model different clay distribution types. These workflows can be used to generate a template in the elastic domain in order to differentiate various clay distributions. Accordingly, our dataset which was taken from a shaly sandstone in the Persian Gulf, was investigated in more details using the generated template for detecting different clay distribution types as well as observing different elastic and reservoir properties when clay distribution type is changed. We observed that there are four different classes (class I, II, III and IV) of properties with different trends in the crossplot of P-wave velocity versus porosity. Class I includes properties which their P-wave velocity increased when porosity is reduced. In contrast, class II includes properties which show a decreasing trend for P-wave velocity when porosity is reduced. Class III belongs to the properties with two different trends towards structural and dispersed clays. These properties do not follow the same trends for P-wave velocity changes versus porosity similar to classes I and II. However, when the given property decreases or increase by moving toward dispersed clay or structural clay, their P-wave may increase or decrease, respectively. Finally, class IV includes properties which their values do not show any particular trend within the given clay distribution types template. [Display omitted] • New topological classification for clay distribution based on plausible configuration of shale/clay particles. • Applicable in reservoir characterization workflows. • Several rock physics-based approaches proposed according to new classification. • A new rock physics template to differentiate various clay distribution. • Four different classes of reservoir and elastic properties of the rock as delineation attributes in sand-clay mixtures. [ABSTRACT FROM AUTHOR]

One of the giant hydrocarbon generation zones in Iran has been developed in the south of the Zagros Mountain Range (i.e., South Zagros), located between the South Zagros and the Persian Gulf in a foreland basin known for high levels of exploration uncertainties (due to the presence of complex structures, multiple source layers, and migration pathways). In this basin, the Permotriassic formations provide for the main reservoir strata, while the hydrocarbon content is deemed to be derived from the "hot shales" of the Silurian-Ordovician Sarchahan Formation, serving as source rock. As the focus of the present research, the Coastal Fars region is developed along the shores of southern Iran and hosts a number of gas reservoirs that have been increasingly discovered since 1970. Developed in the Permotriassic siliciclastics and carbonates of the Faraghan, Dalan, and Kangan Formations, gas reservoirs have made the Coastal Fars a hot zone for exploration and production activities. In this research, one 2D and five 1D models of the basin (at five exploration wells) were constructed to evaluate the maturity of the main Silurian-Ordovician source rock and further investigate the hydrocarbon charge, timing, migration pathways, and accumulation sites. The models were then utilized to investigate the relationship between the presence of multiple shale layers and hydrocarbon content of the reservoir at one of the studied wells using Rock-Eval analysis. This study showed that an uplift that happened after the hydrocarbon generation has led to a dry hole in the study area. The results indicated that the Sarchahan Formation is probably the main source rock across the region, according to previous researches in this area its organic contents were dated back to the late Ordovician rather than the Silurian. The shale intercalations across the reservoirs (Kangan and Upper Dalan), especially in the Khayam Field, were found to produce more than 90% of their hydrocarbon generation potential. No non-indigenous hydrocarbon was identified across the study area, implying that the entire hydrocarbon content was generated by the identified source rocks. Laboratory analysis indicated the presence of type II and type III kerogen at a local heat flow rate of about 65 mW/m2 since the Cretaceous. In total, the Sarchahan Formation was found to reach a maximum burial depth of 6 km, making it matured to overmatured all over the study area. • Source rock characterization based on rock-eval data. • 1D & 2D basin modeling in the Coastal Fars area. • Determination of charge timing. • Identification of migration routes, and accumulation sites in the petroleum system of the area. • Identification of pre-drill prospect areas. [ABSTRACT FROM AUTHOR]

Seismic inversion which is defined as the process of converting seismic boundary reflections into layer elastic properties plays a vital role in different methods of seismic reservoir characterization. It can be done through either deterministic or geostatistical approaches, and geostatistical inversion is the recommended approach for heterogeneous and complicated reservoir due to its capability in capturing the details of a reservoir with the associated uncertainties. However, a common issue with the geostatistical approach is generating a large number of realizations with the same probability which needs to be ranked based on some pre-defined criteria. This study applied a pre-stack geostatistical inversion on an offshore field in the Persian Gulf using a Bayesian framework to produce the joint posterior probability density function (PDF) of P-wave seismic impedance (I P) and S-wave seismic impedance (I S). This global PDF was then, decomposed into local ones at the trace locations using a sequential Gaussian simulation technique. Furthermore, these local PDFs were sampled and 250 realizations of I P and I S generated accordingly. These elastic properties were then converted into lithofacies, and were ranked based on the oil-producing volume lithofacies. Well log data showed a useful distinction of the oil sand lithofacies in the I P vs. V P /V S crossplot, and this domain was used to compute the PDFs for classifying lithofacies derived from the seismic inversion. Moreover, the oil lithofacies volumes were calculated, and the realizations were sorted to generate the probability of P10, P50 and P90 scenarios. Also, the probability of oil presence within the reservoir was computed using all of the classified realizations. • A common issue with geostatistical inversion is generating many realizations. • Oil facies volume is a proper criterion for realization ranking. • Different lithofacies are separated in acoustic impedance versus Vp/Vs crossplot. • Rock physics template improves the lithofacies probability density functions. • Getting away from well site reduces the oil probability due to uncertainties. [ABSTRACT FROM AUTHOR]