Quaternary Research Articles

Contribution of stratigraphy to groundwater motion understanding in chalk: examples of karstogenic horizons of the Pointe de Caux, France

Abstract Chalk groundwater is the main renewable drinking water resource for many cities of the Paris–London Basin. Understanding karst groundwater motion enhancement appears to be a major issue in order to better protect drinking water, to define hydrogeological surveys and to explore the aquifer. In Normandy, the stratigraphy of chalk was investigated in the 1970s and 1980s but this newly developed stratigraphy was not introduced to hydrogeology where chalk aquifers are studied without considering the sequence boundaries and key event surfaces. Upper Normandy is a unique hydrogeological region where both stratigraphy and hydrogeology can be studied together. In this article we focus on field observations and their direct application to scientific theory. Eight hydrogeological surfaces, linked to sequence boundaries or key event surfaces, are identified. They increase porosity and permeability sufficiently to develop karstic features, hereafter called karstogenic horizons. These field observations lead us to propose a new stratified chalk groundwater model. Palaeokarsts and perched springs not aligned to the current base level can be explained from a geodynamic perspective. Global eustatism and regional uplift during the Quaternary Period have to be taken into account with the hydrogeological stratified model, as the controlling factors of the groundwater motion and the karstogenic horizon development. This theory will help hydrogeologists to determine the probability of encountering palaeokarsts above the piezometric level and thereby define well locations with a greater degree of confidence according to the karstogenic horizon drilled. Chemical studies may also be applied to show if this stratified model can enhance water quality by a new well design.

Application of Geoelectric Technique in Groundwater Protection of Quaternary Aquifer in Wadi El Natrun, Egypt

Qualitative and quantitative interpretations of the accessible geoelectrical resistivity data were conducted in the area located to the west of Nile Delta on both sides of the Cairo-Alexandria desert road, between latitudes 30.190816° and 30.745892° N and longitudes 29.797607° and 30.702070° E, in the northern Western Desert of Egypt. The study area is covered by thick sedimentary exposures ranging from the Miocene to the Quaternary period. Geological factors such as lithology and geological structures significantly influence the groundwater in the study area. The Quaternary, Pliocene, and Miocene eras make up the majority of strata in the study region that require water.
 The study conducted twenty-three vertical electrical resistivity soundings using the Schlumberger array to define the shallow subsurface geological inferences and investigate the possibilities of finding underground water accumulations and its contamination with clay lenses. The examination of the obtained electric resistivity values revealed the segmentation of the examined section into five geoelectrical units with lateral variations in thicknesses, lithologies, and features. The five geoelectrical units had different compositions, with the first surface unit consisting of silt clay and relatively high resistivity sands and gravels that have been altered laterally. After the surface unit, resistivity ranges from relatively modest to high. Intercalation of sand and clay occurs in the second unit, followed by lenses of relatively medium-resistance coarse sand and clay in the third and fourth units, possibly forming an aquifer, and finally relatively low-resistance sand and clay in the fifth unit.
 Due to the haphazard drilling of hundreds of water wells, significant hydrogeological and environmental issues, such as soil salinization, water head decline, and groundwater salinity deterioration, have occurred. These issues have attracted significant expenditures in the field of land reclamation, both on small and large-scale projects. The study area is divided into five main geoelectrical layers observed along this cross area, as follows:
 The first surface geoelectrical layer (layer A) is characterized by relatively high resistivity ranging from 8.21 to 595.3 Ohm.m. The thickness of this layer varies from 2.1 to 8.86 m. This layer represents the dry surface cover of the area and consists of gravel, sand, and silt clay.
 The second geoelectrical layer (layer B) represents the dry layer lying above the water-bearing formation. It generally consists of sand and clay intercalation. The resistivity of this layer varies from 3.49 to 91.18 Ohm.m, and the thickness of this layer ranges from 17.13 to 38.3 m.
 The third geoelectrical layer (layer C1) is the water-bearing formation that generally consists of coarse sand and clay. The resistivity of this layer varies from 4.41 to 37.5 Ohm.m, and the thickness ranges from 10.38 to 54 m.
 The fourth geoelectric layer (layer C2) represents the lower part of the water-bearing formation. It consists of clayey sand and clay. The resistivity of this layer varies from 1.83 to 30.1 Ohm.m, and the thickness ranges from 17.78 to 31.35 m.
 The last geoelectric layer (layer D) represents the lower layer of investigation, consisting mainly of clay. The resistivity of this layer is generally low, varying within a narrow range of 26.7-39.8 Ohm.m.
 Finally the current study highlights the necessity of conducting in-depth geomorphological assessment studies before developing new reclamation projects, in addition to soil and water assessment.

Some information about the history of agriculture in the Fergana Valley in the Timurid era in "Boburnom"

The Fergana Valley, is a mountain range in Central Asia, one of the largest mountain ranges in Central Asia. It is surrounded by the Tianshan Mountains in the north and the Gissar Mountains in the south. Mainly in Uzbekistan, partly in Kyrgyzstan and Tajikistan. Most of it is triangular in shape, extending to the northern slopes of the Turkestan and Olay ridges, surrounded by the Qurama and Chatkal ridges in the northwest and the Fergana ridge in the northeast. In the west, a narrow corridor (8–10 km wide) is connected to the Tashkent-Mirzachul basin through the Khojand Gate. Uz. 300 km, width 60–120 km, widest area 170 km, area 22 thousand km. Its height is 330 m in the west and 1000 m in the east. Its general structure is elliptical (almond-shaped). It expands from west to east. The surface of the Fergana Valley is filled with alluvial and proluvial-alluvial sediments of the Quaternary period. The valley was curved in the Coal Age, and in the Middle Ages it was covered with sandy-loamy sediments. During the Cretaceous, there was a shallow sea. By the end of the Paleogene, it was completely dry. The ridges around the valley began to rise sharply in the alpine fold, but were again eroded during denudation. The seabed at the bottom of the valley is covered by continental deposits (300-400 m thick). The surface structure of the Fergana Valley can be divided into several stages (zones). The first stage of the relief occupies the central part of the valley and the lands up to the present headwaters of the Syrdarya at an altitude of 300-400 m. The slope of 200 km in this area is 80 m to the east, southeast and southwest. Accumulative rocks, marine lake deposits, and wind-blown rocks are common on marine deposits. This range includes sand dunes, lakes, and sandy hills.The second stage of the gorge consists of rocky areas (400–600 m) that cover a wide area of ​​rivers and streams. Quaternary alluvial deposits are common, encircling the valley like a ring. The third rung of the relief is the hill zone with a height of 600-1200 m. The Konibodom, Shursuv, Rishtan, Chimgan, Avval, and Muyan hills, which surround the Fergana Valley in the south, are composed of rocky deposits, and the Navkat and eastern hills are composed of lyoss and lyossized clay rocks; large rocky cliffs and cliffs are typical for the terrain. The southern slopes of the Namangan, Chuyet, and Pop hills in northern Fergana descend steeply toward the Syrdarya valley. The plains behind the hills are covered with alluvial rocks. The mountains that surround the valley begin in these accumulative plains. Zahiriddin Muhammad Bobur's book "Boburnoma" also provides information about the climate, geographical structure of the Fergana valley, agricultural products - fruit trees, melons and grains. It is one of the most important sources on the history of Amir Temur and the Temurids. This article describes the state of agricultural development in the Fergana Valley on the basis of information from the memoir "Boburnoma".

Dynamics of landslide processes within the Borisov Plateau of the East Manchurian Highlands

The activation of unfavorable exogenous processes within the Borisov Plateau of the East Manchurian Highlands (landslides, which are the leading ones in the area, karst processes, ravine formations, etc.) is determined by the specific geological structure of the territory, in which eluvial-deluvial formations of the Quaternary age participate in the upper part of the section. They intensively change their physical and mechanical properties when moistened in a typical coastal climate, which causes unfavorable processes and phenomena that lead to deformations of artificial structures and subgrade. The currently used standard and innovative anti-landslide protection structures do not give a positive effect due to the deep bedrock. Recommendations are given for the development of anti-landslide measures.

The Miocene deposits of the Cirò Basin in the evolution of the peri-Ionian region, eastern Calabria

The Cirò Basin is located in the north-eastern partion of Calabria, between the Ionian Sea and the Sila slopes. In this area, basin successions of the Neogene and Quaternary age overlap the Paleozoic metamorphic basement of the Sila Unit. In particular, there are units consisting of continental clastic facies and coastal facies that are the basis of the Tortonian-Messinian transgression. An accurate geological-structural survey, combined with sedimentological and stratigraphic analysis, has allowed to define the limits of the Cirò Basin and the stratigraphic relationships between the various outcropping Miocene deposits. Five distinct litofacies have been recognized, each of which contains both lateral and vertical variations.The main tectonic structures control the architecture and evolution of main Neogene basins of the Calabrian terranes. From the Neogene to the Quaternary, the history of orogenic building was mainly controlled by the activity of NW-SE oriented faults and shear zones characterised by left-trascurrent kinematics. Deformation is well evidenced in the tectono-sedimentary evolution of the wedge-top basins as well as in the retro-arc domain.

Ecological Impacts of Anthropogenic Fire in Southwestern Ohio, USA, Documented from Public Land Survey Records from 1802 and 1803

Public Land Survey System (PLSS) data collected in 1802 and 1803 were analyzed to evaluate the impacts of anthropogenic fire on pre-Euro-American settlement plant communities within a 50,193 ha (194-square-mile) study area east of what is now Dayton, Ohio. Surveyor data were converted to digital point, line, and polygon files using ArcMap software and mapped with some interpolation based on contemporary GIS data layers including topography, soil moisture, soil type, and Quaternary geology. Sixty-one percent of the study area was covered with woody and non-woody plant communities that are known to be shaped and/or maintained by long-term exposure to surface fires of varying intensities and frequencies: oak-hickory forest, oak woodland, oak savanna, oak barrens, and mesic prairie. Prairies and barrens were concentrated adjacent to the corridors of the Mad River and the Little Miami River and their major tributaries, while oak woodlands were concentrated in adjacent uplands. Oak-sugar maple forest covered an additional 29% of the study area, a community that was interpreted to be pyrophilic oak forest transitioning to mesophytic/ pyrophobic forest in the long-term absence of fire.

Phylogeography of the Plateau Pika (Ochotona curzoniae) in Response to the Uplift of the Qinghai-Tibet Plateau

The evolution and current distribution of species on the Qinghai-Tibet Plateau have been significantly impacted by historical occurrences, including the uplift of the plateau and the Quaternary climate upheaval. As a remnant species, the plateau pika (Ochotona curzoniae) is a great model for researching historical events. In this study, 302 samples from 42 sample sites were utilized to analyze the impact of historical events on the evolution and distribution pattern of plateau pikas. The genetic diversity, patterns of differentiation, and historical dynamics of the plateau pika were investigated using molecular markers that included four mitochondrial genes (COI, D-loop, Cytb, and 12S rRNA) and three nuclear genes (GHR, IRBP, and RAG1). The results showed that: (1) The genetic diversity of the plateau pika was high in the Tibetan Plateau (Hd = 0.9997, π = 0.01205), and the plateau pika evolved into five lineages that occupied different geographical areas, with lineage 1 (Group 1) in the south of the Yarlung Zangbo River, lineage 2 (Group 2) in the hinterland of the plateau, lineage 3 (Group 3) in the northeastern part of the plateau, lineage 4 (Group 4) in the Hengduan Mountains, and lineage 5 (Group 5) in the eastern part of the plateau. (2) The gene flow among the five lineages was low, and the differentiation level was high (Nm < 0.25; Fst > 0.25), indicating that the geographical barriers between the five lineages, such as the Yarlung Zangbo River, the Qaidam-Ghuong-Guide Basin, and the Lancang River, effectively promoted the population differentiation of the plateau pika. (3) The plateau pika first spread from the Hengduan Mountains to the entire Qinghai-Tibet Plateau and then conducted small-scale migration and dispersal in several refuges across the plateau in response to climate changes during the glacial and interglacial periods. (4) Except for Group 1 and Group 4, all the other populations exhibited a rapid expansion between 0.06 and 0.01 Mya, but the expansion was considerably delayed or halted by the effects of climate change during the last glacial maximum (0.02 Mya). Overall, the plateau pika on the Qinghai-Tibet Plateau exhibits high genetic diversity, and topographic obstacles, including mountains, valleys, and basins, created by the uplift of the plateau and climatic changes since the Quaternary period have played an important role in the differentiation and historical dynamics of the plateau pika population.

Suitability of the Lower Zab River Sediments for Concrete Works / Southwest of Kirkuk - Northern Iraq

An Engineering study was carried out for five stations in the Lower Zab basin, southwest of Kirkuk, to determine the viability of the Quaternary age sediments for concrete works. The geotechnical evaluation results included that the coarse aggregate's grain size analysis is identical to the gradient class (63.0 mm) according to the [1] classification. As for the gradation of fine aggregate for the sediments of the study area, the results of the granular gradient of the samples after matching them with the limits of AASHTO specification showed that they are identical to the specification with slight differences on some sieves. The elongation and flatness tests showed that the highest percentage of the longitudinal shape is (19.2%) and flat-shaped particles is (28.8%), within permissible limits according to British standard [2], the specific gravity for coarse aggregate was between (2.60 - 2.64) and saturated specific gravity (2.61 - 2.65), and the values of specific weight for fine soil ranged from (2.72 - 2.64) which is suitable for use in concrete works. The results of the laboratory test of the durability tests - The Los Angeles test for the samples showed that the highest percentage for weight loss was (20%), which is suitable for use in the concrete according to the Iraqi standard [3], the results of the laboratory test for stability showed that the percentage of weight loss for coarse aggregate (gravel) by the effect of sodium sulfate solution and for the number of 5 cycles of the samples ranged between (8.3% - 4.1%), which is valid for use in concrete works according to the American specification [4]. The results of the resistance tests - the point load test for stations (S1, S3, S4) within the classification range of very strong - extremely strong, and the two stations (S2, S5) within the class strong - very strong - extremely strong compared to the classification of [5], and they are good for concrete works. It was found from the results of the chemical tests the gypsum content, organic matter content, Total soluble salts, and the sulfate content of the samples of the study area are suitable to for concrete works according to British Standard [6], which is suitable for concrete works, testing the compressive strength of concrete cubes ranged between (24.93 - 18.22 MPa) for age seven days and ranged between (33.02 - 29.76 MPa) for 28 days for reference mixture, Which is (4:2:1 by weight). According to the Iraqi standard specification [7], the compressive strength values of the samples are suitable for regular unreinforced concrete, and in comparison with [8] classification, it was apparent that the concrete produced is of moderate endurance. And suitable for concrete works According to [9].

Neotectonics and Geothermal potential of the East Anatolian Tectonic Block: A case study in Diyadin (Ağrı) geothermal field, NE Turkiye

The study area is Diyadin, which is situated 71 km ESE of Ağrı very close to the Turkish-Iranian State border. It is one of several type localities of promising geothermal fields in the Eastern Anatolia. The neotectonic regime and related structures are dominated by a strike-slip tectonic regime governed by a stress field in the Eastern Anatolia where the greatest principal stress (σ1) is operating in NNW direction (N22°W) while the least principal stress (σ3) is N68°E. This stress field state was proved once more by the tensor solution of the 12 June 2022 Akçift (Muradiye-Van) earthquake of Mw = 5.1. The strike-slip neotectonic regime started at the time of latest Pliocene-early Quaternary and then triggered the first occurrence of the fissure eruption along the NNW trending Kaletepe open fracture. This event was followed by the development of both the two-peaked Tendürek strato-shild volcano and the Diyadin geothermal field (DGF). The geothermal potential of the DGF is high and its most common manifestations are the active tectonic regime and related faults (extensional horse tail strucure), active volcanoes (Tendürek and Ağrı volcanoes), fumeroles, numerous hot water springs to artesian wells, widespread iron-rich alteration zones, actively 
 growing fissure-ridge travertines and the probable presence of the unroofed hypabyssal felsic to intermediate intrusions of Quaternary age at the roots and their near environs of the isolated Quaternary volcanoes in the Eastern Anatolia. In addition, some significant similarities and contrasts are seen between the DGF and the IGF when they are compared.

The possible region of the Late Miocene split of the sandfly subgenus Transphlebotomus Artemiev and the early late Neogene to late Quaternary dispersal of the ancestor of Phlebotomus mascittii Grassi

The distribution of the Mediterranean Transphlebotomus species shows a marked zoogeographical dichotomy in the sense that Phlebotomus mascittii has a wide range in Europe, and the other species are restricted to the East Mediterranean region. The study aimed to investigate how the Neogene to late Quaternary climatic-geographical alterations could influence the split of the sandfly subgenus Transphlebotomus and the speciation of Phlebotomus mascitti. For this purpose, the climatic suitability patterns of the species were modelled for seven Neogene and Quaternary periods and the divergence times of Transphlebotomus clades were estimated. The model results suggest that the common ancestor of the extant Mediterranean-European Transphlebotomus species could be adapted to the Late Miocene climate of Western and Central Europe. Phylogenetic results suggest that the speciation of Ph. mascittii started in the Tortonian period, plausibly related to the rise of the Dinaric land bridge. The Central and Eastern Paratethys Seas could have played an important role in the split of the ancestral Phlebotomus mascittii populations and other Transphlebotomus populations. These other species can be the descendants of ancient Transphlebotomus populations adapted to the hotter and drier climate of the areas south of the Central and Eastern Paratethys. Their divergence could be strongly linked to the formation of the Aegean trench and, later, the Messinian salinity crisis. The Pliocene climatic fluctuations could result in habitat loss of Transphlebotomus populations in Europe which was particularly significant during glacial maxima such as the Last Glacial Maximum.

EVOLUTION OF FLUVIAL TERRACES OF ALAKNANDA AND ITS TRIBUTARIES AND IMPRINTS OF NEOTECTONISAM IN UPPER GANGA BASIN, GARHWAL HIMALAYA, PARTS OF CHAMOLI TEHRI UTTAKASHI & PAURI DISTRICT UTTAR PRADESH (UTTRARKHAND) INDIA

The Geomorphological study in in Alaknanda and its tributaries Ganga basin Garhwal Himalya parts of Chamoli Tehri Uttarkashiand Pauri district Uttar Pradesh (Uttrarkhand with special reference to fluvial terraces has been studied . An area about 10000 Sq.kms in parts of QA sheet 53Jand 53 N on 1:1000000/ 1:50000 scale of has been covered. The area of Upper Ganga basin genetically comprised of terraces of three domains, viz. glacial, fluvio-glacial and fluvial which represent distinct environment of sedimentation of Pleistocene, late Pleistocene and Holocene time during Quaternary period. The glacial terraces are identified at an average elevation of 1150 m above m.s.l, the fluvio-glacial terraces at an average elevation of 975m above m.s.l, and fluvial terraces at an average elevation between 650 to 900 m above m.s.l, The area of Upper Ganga basin consists of Alaknanda,Bhagirathi,Bhilangna, Nandakini, Mandakini, Pindar, Dhauli- Ganga Bal- Ganga , Madhmeshwar Ganga and Berhi Ganga. Amidst these Alaknnda is trunk stream and other are tributaries. The Alaknanda is chracterised by six fluvial terraces followed by Bhagirathi with five terraces , Bhilangna Nandakini four terraces Mandakini /Pindar/Dhauli-Ganga /Balganga three terraces , Madhmshwar Ganga two terraces and Bberhi Ganga one terraces. The Badrinath temple is situated in glaciated trough valley of Alaknanda, which comprise of, four levels of the glacial terraces (lateral moraine), cirque moraine on mountain flanks and the terminal moraine at the base of valley. whereas Kedarnath in the upstream of Mandakini, where number of well developed cirques were identified on high mountain, they are mostly arm chair shaped hollows with a steep to vertical head walls, concave floor and a threshold, these cirques are noticed at an average height of about 4500 m. The Kedarnath temple is situated in glaciated trough valley on quaternary platform formed by coalescing of cirque, lateral moraine and terminal moraine. The-Himalayan thrust like Central thrust Srinagar thrust,, Alaknanda fault, Tons thrust show flattening dip suggesting that they lie at comparatively at shallow depth at short distance, down dip from their out crops, recent movements along the trace of these faults /thrust are not of high and longer magnitude but have considerably affected Quaternary terraces of glacial, fluvio-glacial and fluvial domain of Alaknanda and its tributaries. Beside drainage, river bed profile, landscape architect and over all morphogenetic expression of the area bears the impact of tectonic activity. The imprints of neotectonisam associated in the area indicate that these thrust /faults are active and have posed tectano-ecological problems, bears signatures of sinking of the area, mass wasting activities and neosiemic hazards. The study revealed that there is sharp curvilinear break in morphogenetic expression of the area In North of Wazri in Jamuna valley, North of Uttarkashi in Bhagirathi valley, around Tugnath and Chamoli and South of Joshimuth in Alaknanda valley, which appears to be due to horizontal movement of a sub - tectonic plates towards south, which is causative factor in dislocation in tectonic ecology of the area, it is matter of serious concerned and needs further attention.

Ground Water Quality Evaluation with Using WQI of Selected wells in Mandali Area, Diyala Governorate, East Iraq

Groundwater is necessary to ensure the safety of Mandali's water supply. Groundwater samples were collected from various parts of the city for this study. Two aquifers have been identified: the first is a free bed made up of Quaternary deposits. The second is the primary bed that conveys water, belonging to the Bai Hassan Formation. Nineteen groundwater samples were collected from wells and examined for physicochemical parameters in the current study during October 2021. Samples were analyzed for main cations Ca2+, Mg2+, Na+, and K+; anions HCO3- , SO42- , Cl- and NO3-, pH, Electrical Conductivity, and Total Dissolved Solids. Results indicated that the Samples water is neutral to slightly alkaline. The TDS classifications show that the groundwater samples are classified as fresh to slightly fresh water. All water samples are severely mineralized, except sample W17 which is highly mineralized due to the water feeding from the deep aquifer of Bai Hassan formation. Dominant cation is Na+ followed by Ca2+, Mg2+ then K+, whereas dominant anion SO42 ̶ followed by Cl¯ then HCO3¯. The water type of 8 samples 42% is NaCl type, seven samples 37% is MgSO4 type, three samples 16% is Na2SO4 type, and 1 sample 5% is CaSO4. The diversity in water is because the sediments of the Quaternary age derived from neighboring formations such as Fatha and other formations. According to Piper's diagram, Groundwater samples are mostly earth alkaline water with an increased amount of alkali, high sulfate and chloride. The groundwater in the study area has a wide range of WQI ranging from excellent (W17) while classified as good water (W1, W3, W4, W5, W6, W7, W8, W9, W11, W12, W13, W14, W16, W18, W19) and classified as Poor water (W2, W10, W15) because of the high values of WQI values computed.

Stratigraphic Sequence and Structural Evolution of the Sana'a Basin

The stratigraphic sequence of the Sana'a basin ranges in age from Precambrian to Recent with some periods missing. Lithological outcrops of the Sana'a basin ranging in age from Jurassic to Quaternary, while the subsurface data reveals the occurrences of the Precambrian rocks. 
 Current research discusses the sedimentary and structural evolution of the Sana'a basin and indicates that significant tectonic phases occurred during the Jurassic, Cretaceous, Tertiary and Quaternary periods. Structural effects of these tectonic phases include uplift and subsidence for several times. However, the Sana'a basin formed during the Jurassic time under an inherited and reactivated structural control from the old N-S trend. Field studies indicate that the Sana'a basin was subjected to compression stage during the Paleocene time which resulted in the formation of an anticline with N-S axis, and then at the end of the Paleocene the area is affected by extensional faults to form half grabens such as Wadi Dhahr, and Haddah half grabens.
 During the Tertiary Sana'a area has been affected by huge of volcanic activities especially in the southern part of the Sana' a basin to form the Yemen Plateau, then the major tectonic trends were reactivated by extensional stage which coincided with the NS - NW and ENE - WSW trend. However, most of these faults and fractures are filled by volcanic dykes of different composition. In Quaternary time another volcanic activity has occurred to form a lot of plugs and cones intruded into the old rock units.

Neotectonics of the Sarıköy-Đnova and Çan-Bayramiç-Ezine fault zones: basin formation, age and Slip Rates, NW Anatolia-Turkey

he Sarıköy-Đnova and the Çan-Bayramiç-Ezine fault zones (SIFZ, ÇBEFZ) comprise the southern strand of the North Anatolian Fault System in the Biga Peninsula. They are located in the area between Sarıköy to northeast and the Dalyan settlement around Bozcaada in the North Aegean Sea to southwest. Both of the fault zones are active. This is evidenced by the 6 March 1737 (Ms =7.0) Đnova, 1st February 1809 Hurma (Ms = 6.1), and the 8 February 1826 Güllüce (Ms = 6.2) historical earthquakes resulted from these fault zones. Maximum lengths of fault segments comprising the SIFZ and the ÇBEFZ are 14 km and 15 km, respectively. Based on the maximum lengths of fault segments, the magnitude of the peak earthquakes to be originated from these faults are Mw = 6.3 and 6.6, respectively. Based on both the geological and geographic markers, the total right lateral offsets accumulated on the SIFZ and ÇBEFZ are 12 km and 20 km, respectively. These offset values imply to the slip rates of 4.6 mm/yr and 7.7 mm/yr, respectively. Five pull-apart basins were developed on both fault zones. These are the Sarıköy, Đnova, Kazabat, Çan and Ezine-Bayramiç basins. The first three of them are pure strike-slip pull-apart basins, while the type of the rest basins is superimposed. The angular unconformity between the nondeformed basin fill of Quaternary age and the folded to thrust-faulted basement rocks of pre-Quaternary age reveals strongly that the pull-apart basins have formed during the Quaternary time. This relationship also reveals that the commencement age of the strike-slip neotectonic regime and formation of associated fault zones are the Early Quaternary.

Groundwater control for construction projects in chalk

Abstract Construction excavations and tunnels in chalk can encounter groundwater challenges, including high water flow rates, instability of excavations in weathered chalk and basal instability in overlying aquitards caused by high groundwater pressures in deeper chalk aquifers. In hydrogeological settings where the chalk has been exposed to periglacial weathering during the Quaternary Period the upper zones may be degraded to structureless chalk which can potentially be of very low hydraulic conductivity (putty chalk) or very high hydraulic conductivity (chalk bearings). In deeper, structured chalk groundwater flow tends to be concentrated along fissures associated with pre-existing geological structures such as bedding planes, flint beds or faults. A range of groundwater control strategies can be deployed, including open pumping, pre-drainage pumping, shallow and deep cut-off walls, ground treatment and, for tunnels and shafts, application of fluid counter pressures to exclude groundwater. The strategy appropriate to a given site must be selected based on a thorough understanding of the hydrogeological setting and chalk weathering profile. This requires a ground investigation of appropriate scope, using suitable techniques to characterize the chalk. Borehole geophysics can play a key role in identifying discrete zones of inflow.

Resistivity and Density Structure of Limboto Lake—Pentadio, Gorontalo, Indonesia Based on Magnetotelluric and Gravity Data

Limboto Lake—Pentadio area is located in the province of Gorontalo on the northern arm of Sulawesi Island, Indonesia, which experienced a tectonic process from the Sula Platform collision in the mid-Miocene. This tectonic process led to the westward subduction of the early Miocene and post-collision rifting and uplifting of the arc and subduction along the North Sulawesi Trench during the Late Miocene to the Quaternary periods. The rifting process of the North Sulawesi arc resulted in the formation of the Gorontalo graben zone in the W–E direction. There are geothermal surface manifestations near Limboto Lake, such as hot spring complexes, with temperatures ranging from 74.8 °C to 78.5 °C. To understand the geological structure and prospective geothermal characteristics beneath the investigated area, we performed integrated magnetotelluric and gravity surveys. The preferred 3D resistivity model confirmed the presence of a fault system and a graben system that was filled with conductive bodies (~1–15 Ωm) corresponding to alluvium deposits. This result was in accordance with the 2D density model inferred from the gravity data, where a low-density value indicates the presence of a graben zone. The conceptual model of Limboto Lake—Pentadio was constructed using the information from the MT and gravity results, and from the geological study. The conceptual model illustrates the geothermal system in Limboto Lake—Pentadio, which is controlled by the fault system and the Gorontalo graben system.

Age and Origin of Fluvial Deposits in the Vistula River Valley Near Tarnobrzeg (Sandomierz Basin, Poland): Insights from Sediment Dating and Analysis

Abstract The present research aimed to determine the age and origin of a 4-m sequence of fluvial deposits located in Siedleszczany on the western side of the Tarnobrzeg Monadnock in the Vistula River valley. Initially, these deposits were thought to be sediments of the overflood (Vistulian) terrace. The study revealed that the sand deposits are relatively young Late Holocene sediments, spanning from the 8th century AD to the 15th–16th centuries AD, and the organic material originated from erosion of older Holocene deposits of various ages. This finding was supported by palynological analysis, which identified, besides Holocene pollen grains, also those from Late Glacial and other Quaternary periods, and even from pre-Quaternary ones. Extreme floods in the Vistula valley may be specified as the origin of the sandy sediments in Siedleszczany. Similar large floods occurred in the past when ice jams blocked the main riverbed, leading to the formation of overflow channels. These floods caused rapid erosion of the flood-plain and deposition of sandy sediments in the sheltered marginal areas of the valley, away from high-velocity flood flows. As a result, the fluvial deposits in Siedleszczany, in the Vistula valley, resemble palaeoflood slackwater deposits observed in various regions worldwide.

ЗАГАЛЬНА ГЕОЛОГІЧНА ІСТОРІЯ ЯК ОСНОВА ЄДИНОЇ СТРАТИГРАФІЧНОЇ ШКАЛИ ДОКЕМБРІЙСЬКИХ ПОРІД ПЕРШОТРАВНЕВОГО ТА ГАННІВСЬКОГО РОДОВИЩ КРИВОРІЗЬКОГО ЗАЛІЗОРУДНОГО БАСЕЙНУ

Hannivske deposit of poor magnetite ores is part of the Kryvyi Rih iron ore basin. The deposit is located in the southern part of the Eastern-Hannivka belt at the Northern iron ore district of Kryvbas. Two sets of rocks are involved in the geological structure of the Hannivske deposit: crystalline rocks of the Archaean and Proterozoic, as well as rocks of the Cenozoic sedimentary cover. Archean rocks are represented by plagiogranites and plagiomigmatites of the Dnipropetrovsk Complex (AR2dn) and amphibolites of the Konkska Series (AR3kn). The Proterozoic complex of rocks is formed by the Kryvyi Rih Series (PP1kr), which is divided into five Formations (from bottom to top): Novokryvorizka (PR1nk), Skelyuvatska (PR1sk), Saksaganska (PR1sx), Gdantsivska (PR1gd) and Gleyuvatska (PR1gl). The productive stratum of the Hannivske deposit is the overlying pack of the first ferrous horizon of the Saksaganska Formation of the Kryvyi Rih Series, which, according to the generally accepted stratigraphic scheme of Kryvbas, corresponds to the fifth-sixth ferrous horizon of Saksaganska Formation of Kryvyi Rih Series. Crystalline rocks of the Archaean and Proterozoic are covered by a layer of sedimentary rocks of the Cenozoic: Paleogene (P), Neogene (N) and Quaternary (Q) periods. In the southern part, the Eastern-Hannivka belt (Hannivske deposit) connects with the Pervomayka deposit by a series of numerous sublatitudinal and diagonal faults. In the north-northwest direction, there is a gradual decrease in thickness and wedging of the Eastern-Hannivka belt, including the iron ore stratum. Metasomatic processes in their intense display are observed in the productive stratum of the Hannivske deposit locally, but a significant part of it is covered by weak metasomatic changes. A feature of metasomatic processes was the formation of metasomatic bodies along linear tectonically weakened zones or at their intersection nodes. Multi-stage formation of the Hannivske deposit, active display of various geological processes in the productive and containing stratums (sedimentation, metamorphism, tectogenesis, metasomatosis, hydrothermal, astroblemic phenomena, syngenetic and epigenetic magmatism, hypergenesis, etc.) determined the mineralogical and chemical diversity of the Hannivske deposit ores, the presence in its productive and capacious layers, the manifestation of many metallic and non-metallic minerals, the formation of a complex mineral and raw material base of the deposit.

Testing the Applicability of Quartz and Feldspar for Luminescence Dating of Pleistocene Alluvial Sediments in the Tatra Mountain Foothills, Slovakia

Abstract Luminescence dating is a widely used method in combination with sedimentological analysis for reconstructing the landscape development of the Quaternary period. In this study, quartz and K-feldspar measurements were used to evaluate the luminescence characteristics with the aim of dating the deposits. The sediments were sampled from an abandoned gravel pit in the Biely Váh valley and eight sites in the lower part of the Velická dolina valley, High Tatra Mountains, Slovakia. Optically stimulated luminescence (OSL) showed that quartz had an unstable weak signal, and standard single aliquot regeneration (SAR) dose estimates were unreliable, as were doses from pulsed OSL and differential OSL. Infrared (IR50) and post-IR IR225 stimulation (pIRIR225) signals from K-feldspar grains, on the other hand, gave stronger signals but were, to various extents, influenced by incomplete bleaching, fading and uncertainty due to high (>2D0) doses. We find the uncorrected pIRIR225 ages most reliable, though modern analogues indicate that there may be significant residual from incomplete bleaching for some of the samples. The results of the luminescence analyses, ages and sedimentology are put in the context of landscape dynamics and compared to the known glacial history of the Tatra Mountains.

Evidence for surface rupture of the 1939 Erzincan earthquake based on field data and paleoseismology on the Ezinepazarı Fault (North Anatolian Fault Zone, Central Anatolia)

The Ezinepazarı Fault (EPF) is an active segment that restricts the Niksar Basin in the central part of the North Anatolian Fault Zone and has been the source of the devastating Mw 8.0 earthquake in the last 100 years. Traces of the surface rupture of the EPF, which occurred in AD 1939, can still be observed in the field today as a right-lateral strike-slip character. While paleoseismological studies were mostly focused on the western part of the North Anatolian Fault Zone (NAFZ) in previous studies, the studies on the central and eastern parts of the NAFZ are rarely addressed. In this context, trench-based paleoseismology studies were carried out on the surface rupture traces in order to determine both historical/prehistoric earthquakes caused by the fault and the Quaternary period characteristics of the EPF. According to the data obtained, at least two historical earthquake activities have been detected besides the last 1939 earthquake on the EPF. Accordingly, the first and second events occurred in E1: 5871 ± 2300 BP and E2: 1651 ± 128 BP, respectively. When the determined data are compared with the historical earthquake catalogs, it is concluded that Event 2 (E2) can be correlated with the AD 343 Niksar earthquake; thus, the EPF has an irregular earthquake recurrence interval.