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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

2021

Vol. 47, no. 4

203--216

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).

Geologiczno-inżynierska ocena zwietrzelin gliniastych z południowej Polski

Roguski A.

Przegląd Geologiczny

2014

Vol. 62, nr 10/2

692--698

Weathered rocks occur in Poland e. g. on Lubelszczyzna and Holy Cross Mountains area, in Jura Krakowsko-Czêstochowska region, on Eastern Carpatian flysch and granitoids outcrops in Sudets Mountains. Weathered rocks are often foundation and therefore are subject of thorough and detailed geological and engineering studies. Field CPTU and FVT tests and physical laboratory research were conducted on weathered limestone from Zawiercie and sandstone from Kalwaria Zebrzydowska. These soils were classified as V and VI zone of weathering rock profile. Geomechanical parameters obtained from penetrations and laboratory tests shows a large variation what can be related to variability of their structure and lithology type in each zone of weathering rock profile. This property can give difficulties in formulating engineering and geological properties and delineate geotechnical zones.

Naturally occurring radionuclides and rare earth elements in weathered Japanese soil samples

Sahoo S., Hosoda M., Prasad G., Takahashi H., Sorimachi A., Ishikawa T., Tokonami S., Uchida S.

Acta Geophysica

2013

Vol. 61, no. 4

876--885

The activity concentrations of 226Ra and 228Ac in weathered Japanese soils from two selected prefectures have been measured using a γ-ray spectroscopy system with high purity germanium detector. The uranium, thorium, and rare earth elements (REEs) concentrations were determined from the same soil samples using inductively coupled plasma mass spectrometry (ICP-MS). For example, granitic rocks contain higher amounts of U, Th, and light REEs compared to other igneous rocks such as basalt and andesites. Therefore, it is necessary to understand the interaction between REEs and nature of soils since soils are complex heterogeneous mixture of organic and inorganic solids, water, and gases. In this paper, we will discuss about distribution pattern of 238U and 232Th along with REEs in soil samples of weathered acid rock (granite) collected from two prefectures of Japan: Hiroshima and Miyagi.