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Mud volcano as a feature of emergence in Caspian Sea

Ghaderi Danial, Rahbani Maryam

Oceanologia

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2022

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No. 64 (3)

503--513

EN

An eruption occurred on Dashli Island, 75 km from Baku, on 4th of July 2021, at 21:51 local time. The island is known as the mud volcano and has a history of eruption. We suspected that mud volcano eruption causes emergence on this island. Thus, the effect of this 2021 eruption is investigated using a remote sensing technique. Processed Sentinel-1 and 2 images are employed for this aim. We considered pre- and post-eruption scenarios to evaluate the effect of this eruption on the island. Satellite image classification is used to calculate shoreline changes. Results show that Dashli Island with an area of about 8.55 ha before eruption is now expanded to about 21.8 ha (about 155% increase). The DInSAR method is used to estimate the ground displacement of the island. According to the results, a two-year-displacement before the eruption was between 0.18 and 0.2 m, while a five-month-displacement after the eruption is estimated to be between 0.32 and 0.4 m. Considering ground displacement pre- and post-eruption we estimated 62000 m3 land gaining, due to emergence. We concluded that mud volcano can be counted as a feature of emergence in Dashli Island

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3D subsoil reconstruction of a mud volcano in central Sicily by means of geophysical surveys

Grassi Sabrina, De Guidi Giorgio, Patti Graziano, Brighenti Fabio, Carnemolla Francesco, Imposa Sebastiano

Acta Geophysica

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2022

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Vol. 70, no 3

1083--1102

EN

The upwelling of fluids, subject to overpressure, along with discontinuities in the subsoil, causes the formation of geological structures known as mud volcanoes. These structures, very widespread in the world and in some cases located near inhabited centers, can represent a considerable risk factor for the population, as they can give rise to paroxysmal eruptions, even very violent. The assessment of the characteristics and structure of the subsoil of the areas affected by this phenomenon can prove to be a useful tool for risk mitigation. Non-invasive geophysical surveys were carried out in the area of the active cone of the Santa Barbara mud volcano in order to obtain a 3D characterization of the subsoil. Through the processing and integration of data derived from active and passive seismic surveys was obtained, a 3D model showing the seismostratigraphic subsoil structure. The electrical resistivity tomography surveys provided results comparable to those obtained from seismic surveys and supplied information on the perimetral areas of the mud volcano. The information obtained is useful to study the boundary conditions that influence short-scale activity. Furthermore, this study seeks to evaluate the possibility of using the proposed methodological approach for monitoring the variations that occur over time in the areas affected by mud volcanoes phenomenon.

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X-ray diffraction studies of onshore mud volcanoes in parts of the Upper Benue Trough, northeastern Nigeria

Musa Ojochenemi K., Kurowska Ewa E., Krzykawski Tomasz, Onimisi Jimoh A.

Geology, Geophysics and Environment

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2021

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Vol. 47, no. 4

203--216

EN

The mineralogical studies of clay from the onshore mud volcanoes discovered in parts of the Upper Benue Trough of Nigeria provide a clue about the geological formation from which the extruded mud originates. The study area is a part of the Cretaceous Upper Benue Trough filled with Early Cretaceous continental deposits and Late Cretaceous marine deposits, having a history of magmatism dating from the Albian to the Pleistocene. The study approach involves integrated inorganic geochemical analysis of the samples to reveal their composition and origin. The results of XRD analysis of the fresh clays from the mud volcano revealed the presence of quartz, kaolinite, and other clay minerals (illite-smectite), feldspars, and in a much lower quantities, other accessory minerals including muscovite, evaporites, calcite and dolomite, trona, barite, goethite. The saprolite samples are composed mainly of quartz, kaolinite, smectite-illite associations, and feldspars, traces of goethite, calcite, and evaporate minerals (sylvite, halite). The presence of calcite, dolomite, sylvite, and halite suggests the marine origin of the rocks, while trona mineral is a non-marine evaporate. The coexistence of these minerals in some of the analyzed samples suggests the deposition of sediments in a transitional environment of deposition. Traces of marine minerals are present in some of the samples but completely absent in others collected from another site. This suggests that the source rock formations from which the material originated are within the Upper Bima Sandstone interpreted as being deposited in a non-marine environment or the Yolde Formation, which is known as a transitional unit (transitional between the outcropping continental Upper Bima Sandstone and marine Pindiga Formation).

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Characterization of some selected mud volcanoes of southern Taiwan

Kumar A., Yang T.-H., Walia V., Sung Y.-C., Lee H.-F., Lin S.-J., Wen K.-L.

Acta Geophysica

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2018

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Vol. 66, no. 5

1257--1265

EN

In the present study, some mud volcanoes in Pingtung and Kaohsiung areas were selected. The selected mud volcanoes are located above the mud diaper system in southern Taiwan. Three different sampling techniques were used to collect samples in and around the said mud volcanoes. The results show that river water samples from different places fall on the meteoric line. Mud samples are found to be heavier in oxygen isotope while hydrogen isotope remains the same. Soil gas samples were also collected at the depth of 1 m and dissolved gases from the mud volcanic site (or nearby) were collected for gas chromatography analyses. Soil gas samples and dissolved gas from mud pool and groundwater were analyzed for radon concentration using RAD7 (solid-state nuclear track detector) bi-weekly. Long-term investigation will be needed to understand the relationship of mud volcanoes the eruption cycle with gas composition variations. It will also help to understand their relationship with tectonic activities in the region.

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Tectonic control on the distribution of onshore mud volcanoes in parts of the Upper Benue Trough, northeastern Nigeria

Musa O. K., Kurowska E. E., Schoeneich K., Alagbe S. A., Ayok J.

Contemporary Trends in Geoscience

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2016

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Vol. 5, iss. 1

28--45

EN

Onshore mud volcanoes are rare geological phenomena, which in Nigeria were reported for the first time few years ago in the Upper Benue Trough. In this study a detail geological mapping of the area of mud volcanoes occurrence was carried out, with the primary aim of defining their relationship, if any, to the structural geology there. The systematic field reconnaissance included field observations of the structural features, as well as analysis of the location and distribution of the onshore mud volcanoes, marking their locations on the topographic and geological maps, analysis of the aerial photographs and satellite images. The study area covered the central part of the Upper Benue Trough where the onshore mud volcanoes were found. The study area is the part of a sedimentary basin comprising Cretaceous clastic rocks that have been deformed intensively by a network of faults often embedded in the underlying Precambrian basement. This network of faults underwent a rejuvenation period from the Aptian to the Palaeocene. The most prominent tectonic structure in the study area is the NE – SW trending Kaltungo Fault Zone, however, there are other minor faults with N – S and NW – SE trends. This study shows that the mud volcanoes found in the study area are usually located near or within fault zones, within the outcropping Upper Cretaceous Yolde Formation and Upper Bima Sandstone, both of which were deformed by the Kaltungo faults, as well as by other minor faults. Worldwide, incidences of onshore mud volcano formation are usually attributed to areas of tectonic activity, rapid sedimentation or hydrocarbon occurrence. In this study, the interpretation of the field observations and mapping results, combined with information on the structural evolution of the study area and seismic pattern (very scarce), have led to the conclusion that the location of onshore mud volcanoes in the Upper Benue Trough, being located along the fault zones, is structurally controlled. The close relationship between mud volcano location and the structural framework of the area may be interpreted as one of several possible subsurface geological responses to present tectonic activity.