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General geology
Published in M.L. Jeremic, Rock Mechanics in Salt Mining, 2020
The chloride facies in the Tuzla basin, former Yugoslavia, originated in small, shallow basins with salt solutions located on the periphery of Pannonian Sea – Paratetis. The evaporite-bearing strata were deposited 18 million years ago during a marine regression (salt facies), and marine transgression (marl, claystone, dolostone). The evaporite-bearing strata are called the ‘banded series’ (Figure 1.4.4). It is not clear, however, if deposition of evaporites occurred in a marine lagoon or salty lakes, but it is certain that at this time and in this region the climate varied from moderate tropical to aerial which facilitated the deposition of the chloride salts facies in the beds with a thickness over 30 m. Further sedimentation of marine sediments (Tortonian) formed a thick and protective cover over the halite deposits. The original salt deposits experienced chemical alteration (solution of salt minerals) and mechanical alteration (folding and multiplication of original beds)16.
Diastrophism
Published in Richard J. Chorley, Stanley A. Schumm, David E. Sugden, Geomorphology, 2019
Richard J. Chorley, Stanley A. Schumm, David E. Sugden
The greater protuberance of the zones of spreading during their more active phase has the effect of decreasing the capacity of the ocean basins and creating a tendency for a eustatic rise of sea level. Provided that this is not accompanied by widespread orogeny – which it may be – this will lead to a marine transgression of the continental edges and a greater depth of coastal water in which a greater rate of sedimentation can occur. These sedimentary wedges along the more stable ‘trailing’ continental margins form one type of downbuckling, the paraliageosyncline (coastal geosyncline) (see Figure 5.18B). Subsidence along these zones was probably initiated by the foundering of the raw continental edge following its original fracture and this may have been aided subsequently by the thermal contraction of the lithosphere as it moved away from the hot zone of spreading, but it is probable that continued subsidence along paraliageosynclines has been assisted by the thicknesses of sediments laid down, particularly during the transgressive phases. Continued subsidence may eventually so thin and weaken the lithospheric plate that failure, subduction and cordilleran type orogeny may result.
The impact of climate transitions on the radionuclide transport through a sedimentary aquifer
Published in Jude Cobbing, Shafick Adams, Ingrid Dennis, Kornelius Riemann, Assessing and Managing Groundwater in Different Environments, 2013
Judith Flügge, Madlen Stockmann, Anke Schneider, Ulrich Noseck
Quaternary sea-level oscillations can be regarded as a result of the Milankovitch cycles and hence are dependent on the global ice volume (Imbrie et al., 1984). In Northern Germany, the sea-level variations amounted to several decametres up to ca. 120 m in the course of the past 18 000 years (Streif, 2004). Several Quaternary North Sea transgressions are recorded for Northern Germany. In the geological past, periods of seawater inundation in Northern Germany persisted for a few thousand years only (Streif, 2004). The maximum extension of the Quaternary marine transgressions occurred during the Holstein Warm Stage, which lasted from 335 000 to 330 000 years Before Present (BP). The marine transgression occurred in the form of a single, uninterrupted sea-level rise with an average rising rate of 1 m per 100 years (Streif, 2004). This led to a local sea-level rise of more than 50 m (Streif, 2004) up to ca. 65 m (Linke et al., 1985), while the global sea-level rise amounted to more than 100 m (Rohling et al., 1998). The sea-level high-stand persisted for ca. 5 000 years.
Metal(loid)s as Hydrologic Tracers for Particle Transport via Fluvial Processes from the Yellow Pine Mine and Mill in an Arid Environment of Southern Nevada, USA
Published in Soil and Sediment Contamination: An International Journal, 2023
Douglas B Sims, Andressa C Buch, Amanda C Hudson, Mark Garner, John E Keller, Desta Woldetsadik, Paul McBurnett, Kazumasa Lindley, Tshivute Iipinge, Mouloud Ait Mechedal, Jennifer Arostegui, Ryan A. Busch, Liliauna E Beckstrom, Joseph J. Piacentini
Geological units exposed in the Goodsprings Quadrangle include a wide variety of unconsolidated alluvial deposits, intrusive igneous rocks, and surface lavas sitting on Paleozoic and Mesozoic consolidated rocks. The basement rock in this area consists of Precambrian granite and gneiss with orthoclase crystals in a dark biotite matrix (Hewett 1931). Directly overlying this bedrock are members of the Tonto Group, a series of sedimentary rocks that make up the basal sequence of Cambrian-age strata exposed in the sides of the Grand Canyon. The bottom member is the Tapeats sandstone, which is overlain by the Bright Angel Shale, a green and purple-red siltstone and shale interbedded with sandstone (Rose 2006). The third member of this Group, the Muav Limestone, is absent in the Goodsprings area (Hewett 1931). This sequence of rocks (sandstone – shale – limestone) indicates a marine transgression as sea level rose resulting in coastal flooding (Rose 2006). These units are not exposed at the surface within this Quadrangle (Hewett 1931).
Tephrostratigraphic constraints on sedimentation and tectonism in the Whanganui Basin, New Zealand
Published in New Zealand Journal of Geology and Geophysics, 2020
Callum Rees, Julie Palmer, Alan Palmer
The first influx of fluvial conglomerate within the Whanganui Basin between the Whanganui and Rangitikei rivers does not occur until Toms Conglomerate, Shakespeare Group (c. 0.6 Ma); whilst in the Oroua Valley, we have evidence for influxes as early as c. 1.6 Ma (Figure 8). This trend is confirmed in the Pohangina Valley, where a change to non-marine sedimentation occurs at c. 1.6 Ma. We suggest progressive influxes of coarse greywacke detritus were intermittently prograding southwestwards into the Whanganui Basin during sea level low stands, likely forming an alluvial plain about the emergent base of the paleo-axial ranges. Low stand periods being characterised by a lowering of the tree line in the ranges, increased mechanical breakdown and erosion, overloading of river headwaters with detritus and fluvial aggradation (Palmer and Pillans 1996). Incision of the Whanganui Basin fill occurred during marine transgression, as the climate warmed, erosion rates lowered in headwater catchments and paleo-rivers formed localised valleys that retreated landward as sea level continued to rise. Substantial erosion and reworking is evidenced by common rip up clasts, channel cut and fill and erosive contacts (Figure 6). Progressive flooding of the eastern basin margin during marine transgression and high stand infilled local valley systems, such that they were transient, short-lived features on a shallow gradient coastline. Heterolithic deposition occurred within coastal plain to marginal margin environments, including common back swamp environments where preservation of organic matter and tephra-fall beds occurred (Figure 4F).
Geological field guides as educational tools: the Coorong, South Australia
Published in Australian Journal of Earth Sciences, 2019
Sea level curve for the past 130,000 years, in relation to Marine Isotope Stages 1 to 5, derived from observations of flights of coral terraces on the uplifting Huon Peninsula, Papua New Guinea; adapted from Lambeck and Chappell (2001). The thickness of the line of the curve is an expression of the degree of uncertainty of the calculated sea-levels. Numbers 1 to 5 refer to episodes of time (stages) defined by marine oxygen isotopes. The Last Glacial Maximum, when sea level was about 120 m lower than at present, is shown within Stage 2. The Last Interglacial warm period (within Stage 5) occurred about 130,000 to 120,000 years ago, when sea level was about 2 m higher than at present. The present interglacial warm period (Stage 1) has existed for little more than the past 10 000 years. The rapid rise in sea level during the transition from Stage 2 to Stage 1 is known as the Postglacial Marine Transgression. The last 10,000 years (approximately) constitutes the Holocene Epoch.