Appraisal for the environment, weathering and provenance of Upper Cretaceous-Lower Tertiary shales, Western Desert, Egypt

The combination of the mineralogical and geochemical composition of shales is considered a key to decipher their environment evolution, weathering, climatic conditions, and provenance. The Upper Cretaceous-Lower Tertiary succession is extensively dispersed in Egypt. The present work is devoted to studying the Dakhla shales of (Maastrichtian- Danian), Duwi (Campanian) and Quseir (pre-Campanian) formations. Chemical and mineralogical analyses were conducted by using seven representative surface sections from Dakhla Oasis. Dakhla shales are dominates by Smectite and kaolinite. The average percentages of SiO2, Al2O3, CaO, MgO, Na2O and K2O are subordinate values. In contrast, Al2O3 contents of Dakhla shale, TiO2, P2O5 and Fe2O3, contents are relatively higher than common shale composition. The CIA and CIW high values due to clay minerals and the absence of feldspars. This is also confirmed by the smectite domination and subordinate kaolinite in these formations. The ICV values for Dakhla and Duwi shales are 0.59 and 0.74 (ICV < 1). The shale is mature and deposited in a quiescent environment. Whereas the ICV for Quseir shale is 1.24, it can be incidental that it is immature. The shale is wholly detrital and a product of moderate to intensive weathering. The provenance was constituted of granitic and basaltic source rocks, and the parent provenance is basalt. Consequently, the shale is deposited under fluvio-marine environments, and the prevailed condition was of alkaline chemical affinity probably passed through different environments varying from a fluvial, eolian and shallow marine.

The increase in non-marital childbearing and its link to educational expansion

The increase in non-marital childbearing has coincided with educational expansion, although non-marital childbirths are more common among the low-educated population. This article quantifies the contribution of changes in education-specific rates of non-marital childbearing and educational distribution of parents to increases in non-marital childbearing among Finnish first-time parents over the period 1970–2009. Using Finnish register data on first-time mothers ( N = 112,730) and fathers ( N = 108,812), the study decomposes changes in the proportion of non-marital first childbearing in pairwise comparisons of successive decades for four educational segments: low educated (International Standard Classification of Education (ISCED) 0–2), medium educated (ISCED 3–4), lower tertiary educated (ISCED 5–6) and upper tertiary educated (ISCED 7–8). The findings show that the increase in non-marital first-time births was mainly attributable to the large population of medium-educated women and men and the growing segment of lower tertiary-educated women. The highest proportion of non-marital first-time childbearing remained among the low-educated population, but diminishing group size meant their overall contribution was small. The growing upper tertiary-educated population increased its contribution to non-marital childbearing but still exhibited the lowest non-marital childbearing rates. We conclude that the medium-educated population merits increased scholarly attention for its important contribution to population-level changes.

Existence of new rock unit of pink dolomite within the Midland succession of Balanch area, Darchula, Far-Western Nepal

Geological setting and lithostratigraphy of Balanch area in the Darchula District, Far-western Nepal has been worked out with the aim to study the stratigraphy of the area. It has been found that the Bitule Dolomite developed in this area possibly represents the youngest rock unit of the Midland Group of the Nepal Lesser Himalaya. The Balanch area lies within the autochthonous zone of the Lesser Himalaya. The rock succession has been divided into six units: Bagadi Slate, Simar Talc Beds, Baril Dolomite, Tupkan Slate, Bitule Dolomite, and Balligad Sandstone. The Balligad Sandstone possibly belongs to the rock succession of Lower Tertiary whereas all other units belong to the Midland Group. From south to north, the area is characterized by the development of three tectonic zones. The southern zone is characterized by the development of oldest rock unit (Bagadi Slate) having NW to NE trend and dipping towards south and possibly thrusted over the middle zone. The middle zone is characterized by the development of the Simar Talc Beds, Baril Dolomite, and the Tupkan Slate, and also thrusted over rock succession of the northern zone, which is characterized by the development of the Bitule Dolomite and the Balligad Sandstone, the youngest rock units of the area. Geological setting and lithostratigraphy of Balanch area in the Darchula District, Far-western Nepal has been worked out with the aim to study the stratigraphy of the area. It has been found that the Bitule Dolomite developed in this area possibly represents the youngest rock unit of the Midland Group of the Nepal Lesser Himalaya. The Balanch area lies within the autochthonous zone of the Lesser Himalaya. The rock succession has been divided into six units: Bagadi Slate, Simar Talc Beds, Baril Dolomite, Tupkan Slate, Bitule Dolomite, and Balligad Sandstone. The Balligad Sandstone possibly belongs to the rock succession of Lower Tertiary whereas all other units belong to the Midland Group. From south to north, the area is characterized by the development of three tectonic zones. The southern zone is characterized by the development of oldest rock unit (Bagadi Slate) having NW to NE trend and dipping towards south and possibly thrusted over the middle zone. The middle zone is characterized by the development of the Simar Talc Beds, Baril Dolomite, and the Tupkan Slate, and also thrusted over rock succession of the northern zone, which is characterized by the development of the Bitule Dolomite and the Balligad Sandstone, the youngest rock units of the area.