lower pleistocene
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2021 ◽  
Vol 21 (3) ◽  
pp. 299-310
Author(s):  
Duc Huy Trieu ◽  
Ngoc Thanh Tong ◽  
Van Lam Nguyen ◽  
Ba Quyen Pham ◽  
Dai Phuc Hoang ◽  
...  

Hanoi city has abundant groundwater, supplemented by the surface water (mainly Red River) all year round, and the extensive shallow aquifers, which are easily exploited by large-diameter wells. There always exists some open hydrogeological windows in the Red River area with an open structure; therefore, the groundwater has a strained hydraulic relationship with the Red River water system Along the Red River from Ba Vi to the end of Phu Xuyen district, there are nine regions with three types and four sub-types of different hydrogeological structures. In particular, the sub-type I-A of the groundwater has a tight hydraulic correlation with the Red River since the hydrogeological structure of the Red River bottom includes three aquifers: Holocene (qh), upper Pleistocene (qp2), and lower Pleistocene (qp1) that constructs a hydraulic system. The sub-type I-B is characterized by the hydrogeological structure at the Red River bottom, including the aquitard in Vinh Phuc and two aquifers qp2 and qp1, which form a hydraulic system. The sub-type II-A is distinguished by the fact that the Red River crosses the aquifer qh; there are no aquitards between the aquifer qh and qp2 to form a hydraulic system; the aquitard separates the aquifer qp1. The sub-type II-B is identified by the fact that the Red River crossing the aquifer qh; there is an aquitard between the aquifer qh and qp2; there are no aquitards between the aquifer qp2 and qp1 so that can create a hydraulic system. Type III has a solid existence of both aquifers and aquitards; thus, the hydraulic relationship between the Red River and the aquifers qp2 versus qp1 is inferior.


Author(s):  
Yaroslav Kravchuk ◽  
Vasyl Chalyk

The analysis of four stages of relief development is done, which created the corresponding complexes within the Solotvyno hollow. The main attention is paid to the morphostructural and morphosculptural features. The morphostructures of the third and fourth orders are distinguished. Among the elements of morphosculpture the main attention is paid to denudation and denudation-accumulative surfaces (Kycherska, Skrydeyska, Boronyavska). The role of the new technological movements in the formation of these surfaces and river valleys was rated. The second stage of the upper baden is associated with the retreat of the sea basin and the division of the land into mountains. The main features of the modern relief were formed in the Pliocene Pleistocene stage - a river network with a complex of terraces, denudation and denudation-accumulative surfaces, quest forms in the marginal zone. Age of the Kicherska denudation surface is pannon-pont. According to the palynological analysis, the estimated age of the Skrydei denudation-accumulative surface is upper pliocene-lower pleistocene. The age of the Boronyava surface is considered to be Eopleistocene, and pebbles of metamorphic rocks are present in its alluvium (up to 5%). In the modern period, newer differentiated tectonic movements have become more active, which have contributed to the active manifestation of exogenous processes: erosion, landslides, and halogen karst. Key words: denudation and denudation-accumulative surfaces; power of ancient alluvium; modern morphodynamic processes.


2021 ◽  
pp. 4-7
Author(s):  
M.Ya. Aghamammadova ◽  

Petroleum sediments in Azerbaijan have been researched and described by now in the form of complexes. Not only oil and gas deposits, but also the fields and accumulations of bitumen, bituminized rocks and oil shales are associated with these sediments. Furthermore, there are iodine, brom, the components of natural soda and so on in the oil, oil products and sediments as well. Alongside with it, a great amount of valuable metals present in the content of oil, produced water, bitumen and oil shales as an addition. This circumstance dictates the necessity of formation division of oil sediments. There are ten oil formations: Upper Pliocene-Lower Pleistocene, oil bearing-terrigenic; Middle Pliocene, oil-gas-bituminous-terrigenic; diatom-oil bearing-sand-clay; Miocene, oil-bituminous-sand-aleurite; Upper Oligocene-Miocene, oil bearing-terrigenic-carbonate; Eocene, oil bearing-clay-sand-marly; Upper Cretaceous, oil bearing-carbonate; Lower Cretaceous, oil bearing-terrigenic-carbonate; Upper Jurassic, oil bearing-sand-aleurite.


2021 ◽  
Author(s):  
Ypermachia Dimitriou ◽  
Penelope Papadopoulou ◽  
Maria Kolendrianou ◽  
Maria Tsoni ◽  
George Iliopoulos

<p>The genus Cyprideis is one of the most widespread ostracod representative of the Pleistocene brackish palaeoenvironments. Especially <em>Cyprideis torosa </em>is often found in great numbers and even in monospecific taphocoenoses and for this reason its study is very useful for palaeoenvironmental reconstructions.  The identification of different species of Cyprideis is often complicated and needs careful morphology inspection. This becomes even more difficult in the case of endemic species which present significant similarities with each other.  In this work, we have studied and analyzed several  Cyprideis species (<em>C.torosa, C. frydaci, C.dictyoti, C. pannonica, C. elisabeta, C. seminulum, C. heterostigma</em>) deriving from brackish palaeoenvironments of a Lower Pleistocene marl sequence in Sousaki Basin (Northeastern Corinth Graben, Greece). More specifically size measurements and geometric morphometrics (lateral valve outline of both right and left valves as well as females and males) were used in order to attest the similarities and dissimilarities between the different species and draw conclusions about their origin.  According to the valve outline and the multivariate analysis a close relationship between the valve shape of all Cyprideis species can be noticed. <em>C. torosa</em> is commonly grouped with <em>C. pannonica</em> except in the male right valve where the two species show some differences.  The endemic species <em>C. frydaci</em> and <em>C. dictyoti</em> can be identified by the differences in the right valve of the male and female respectively.  The other species could not be substantially differentiated using just the outline analysis which possibly denotes their common genetic origin.  The valve outline has proved to be a very useful character for recognizing the different species especially when the two valves of both females and males are considered. More analyses of representative species of Miocene and Pliocene Cyprideis are needed in order to establish their phylogenetic relationships and draw conclusions about their common ancestor.</p>


2021 ◽  
Author(s):  
Martin J. Head ◽  
Philip L. Gibbard ◽  
Jan Zalasiewicz

<p>The Holocene and Pleistocene series/epochs have each long been divided into Early, Middle and Late subseries/subepochs, although their formalization had been complicated by the hitherto absence of this rank from the International Chronostratigraphic Chart.  On 14th June 2018, the Holocene was formally subdivided into the Greenlandian, Northgrippian and Meghalayan stages/ages and their corresponding Lower/Early, Middle, Upper/Late subseries/subepochs, each defined by a Global Boundary Stratotype Section and Point (GSSP). The GSSP for the lowermost stage, the Greenlandian, is that of the Holocene as previously defined in the NGRIP2 Greenland ice core, and dated at 11,700 yr b2k (before 2000 CE). The GSSP for the Northgrippian is in the NGRIP1 Greenland ice core, and dated at 8236 yr b2k, whereas that for the Meghalayan is located in a speleothem from Mawmluh Cave, Meghalaya, northeast India with a date of 4250 yr b2k (Walker et al., 2018).  The Pleistocene Series/Epoch of the Quaternary System/Period has been divided unofficially into three subseries/subepochs since at least the 1870s.  On 30th January 2020, two proposals were ratified: 1) the Lower Pleistocene Subseries, comprising the Gelasian Stage and the superjacent Calabrian Stage, with a base defined by the GSSP for the Gelasian Stage, the Pleistocene Series, and the Quaternary System, and currently dated at 2.58 Ma; and 2) the term Upper Pleistocene, at the rank of subseries, with a base currently undefined but provisionally dated at ~129 ka.  The Middle Pleistocene and its corresponding Chibanian Stage/Age had meanwhile been formalized on January 17, 2020 with a GSSP in the Chiba section, Japan.  The GSSP is placed 1.1 m below the directional midpoint of the Matuyama–Brunhes Chron boundary, at the base of a regional lithostratigraphic marker, the Ontake-Byakubi-E tephra bed, in the Chiba section. The GSSP has an astronomical age of 774.1 ka and is placed just below the top of Marine Isotope Substage 19c.  These ratifications nominally complete the official division of the Quaternary into subseries/subepochs, although the Upper Pleistocene and its corresponding stage remain to be defined by GSSP.  The Anthropocene is currently an unofficial unit, while analysis of potential candidate GSSP locations is progressing in preparation for a formalization proposal.  If approved, it would terminate the Holocene at around the year 1952, assuming it is defined at series/epoch rank.</p><p>Head, M.J., Pillans, B., and Zalasiewicz, J.A., in press. Formal ratification of subseries/subepochs for the Pleistocene Series/Epoch of the Quaternary System/Period. Episodes</p><p>Suganuma, Y., Okada, M., Head, M.J., et al., in press. Formal ratification of the Global Boundary Stratotype Section and Point (GSSP) for the Chibanian Stage and Middle Pleistocene Subseries of the Quaternary System: the Chiba Section, Japan.  Episodes</p><p>Walker, M., Head, M.J., Berkelhammer, M. et al., 2018.  Formal ratification of the subdivision of the Holocene Series/Epoch (Quaternary System/Period): two new Global Boundary Stratotype Sections and Points (GSSPs) and three new stages/subseries. Episodes 41(4): 213–223. </p>


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