The Effect of Sandstone Composition on Distribution of Tafoni Landforms in the Aghajari Sandstone, Northwest of Masjed Soleyman, Iran

The Aghajari sandstone layers are located in the west of Zagros Mountains from several centimeters thicknesses to maximum 6 meters with carbonating content. Laboratory and fieldwork show high amount of carbonate content through sandstone layers and tafoni and honeycombs (THs) in early layers. In the study area three parameters have the most effective impactful factors in tafoni and honeycombs (THs) including matrix, carbonate content, and porosity. In this study result shows overlays of high ranges of CaCO3, porosity, and low matrix in the early layers (especially in A, B, C, D, and H layers) with tafoni and honeycombs (THs). Overall, we conclude that matrix and CaCO3 (carbonate clast including carbonate lithics, fragment fossils, and Pellet) and porosity have direct relationships and matrix reverse relationships with tafoni and honeycombs (THs) in the Aghajari sandstones layers.

Paleocurrents, Paleohydraulics, and Palaegeography of Miocene-Pliocene Siwalik Foreland Basin of India

Early Miocene-Pliocene Middle Siwalik Subgroup of Kuluchaur area, Uttarakhand, North India, comprises sheet-like, coarse to medium grained, cross bedded sandstone bodies and multistoreyed variegated mudstones. Paleocurrent study shows commonly unimodal and locally bimodal distribution and displays a high magnitude of resultant (R*=0.7337) oriented towards south-southwest (206° ± 42.27°). Palaeochannel morphological attributes suggest that the depositing river system was about 230 m wide and 4.5 m deep. These broad, shallow, and low sinuous channels with extensive flood plain flowed on a steeper slope (0.00043 degrees) with flow velocity of 60–140 cm/sec. It is visualized that the immature Middle Siwalik rocks were deposited by southward flowing braided rivers transverse to the Himalayas, predominantly in the form of overlapping alluvial fans similar to those depositing sediments at present in the Indo-Gangetic plains. Fairly consistent fluvial palaeoslopes, together with enormous thickness of sediments, are evidences of rapid subsidence of the basin. We conclude that the paleogeography of Indian subcontinent established at the onset of Miocene-Pliocene Siwalik sedimentation is continuing till today.

Rare Earths in Geological Formations of Central Region of the Dniester River Basin, Republic of Moldova

In the different varieties of crystalline basement of Archean and Proterozoic age and in Vendian (Ediacaran) basal layers of platform coverture in the Central Basin of the Dniester River were found relatively high concentrations of Lanthanum, Cerium, Yttrium, Ytterbium, and Scandium. Because the petrographic formations, which are genetic associated with RE elements in Dniester region are absent, the origin of these elements is unclear. At the same time, in the geological mapping, it was detect that geochemical aureoles of REE, found in the northern region of Republic of Moldova, are generated by accessory minerals monazite and zircon present in the rock of basement platform and fragments of crystalline rock in the composition of terrigenous formations from basal levels of sedimentary coverture. Probably mentioned minerals are brought from Ukrainian Crystalline Shield regions, in which are spread varieties of granitic rocks and alkaline pegmatite. It is not excluded that in these basal layers in the sedimentogenes processes and differentiation of detrital material to be formed the mechanic aureoles rich in monazite and zircon, which in turn can form significant concentrations of rare earths. To solve the perspective problem of detection of industrial mineral accumulations of RE in the central region of the Dniester River basin, it is necessary to conduct within this area detailed geological and geochemical research.

Trace Element Soil Quality Status of Mt. Cameroon Soils

The concentrations of Cu, Co, Zn, Ni, V, and Cr in topsoils at six sites located along the lower slopes of Mt. Cameroon were assessed for their potential toxicity to humans and the ecosystem. Soils were collected from horizons down to a depth of 70 cm and analysed for trace element concentration by ICP-MS technique. The Dutch soil quality standards which use %clay/silt and organic matter content to derive target values were used to assess the contamination levels of the soils. The content of these soils was also compared to the United Kingdom ICRCL “soil trigger” values. Zinc and Cu values were persistently below the normal value (A) and occurred in the lower elevation, the region of extreme weathering, while Cr and V values were above the intervention (C) values. The high content of Cr in common fertilisers poses a potential risk in toxicity in the higher elevations experiencing lower weathering rates, where soil Cr levels are elevated.

A Comparison of Maceral and Microlithotype Indices for Interpretation of Coals in the Samarinda Area, Lower Kutai Basin, Indonesia

Strata of the Middle Miocene Balikpapan Formation from the Lower Kutai basin are well exposed in a section near the Samarinda city, East Kalimantan, Indonesia. The succession is characterized by thick sandstone bodies alternating with shales and coal beds. A 250 m thick composite section of exposed sediments (not including the soil interval) was measured, from which 25 coal samples were collected. Petrographic, microlithotype, and maceral analyses were performed in order to determine the depositional environment of the Samarinda coals. In order to assess the development of paleomires, coal facies diagrams were obtained from microlithotype and maceral composition. According to the organic petrologic results, the Samarinda coals represent a highly degraded humodetrinite-rich group deposited from terrestrial into telmatic condition of peat formation with vegetation characteristics of highly degraded woody forest type evolved under alternate oxic to anoxic moor conditions. These formed with intermittent moderate to high flooding as the paleopeat environment shifted from mesotrophic to ombrotrophic.