scholarly journals Reinterpretation of the Neogene sediments of the Bree Uplift, NE Belgium

2020 ◽  
Vol 23 (3-4) ◽  
Author(s):  
Rik HOUTHUYS ◽  
Johan MATTHIJS
Keyword(s):  
Tidal Basin ◽  
Marine Sand ◽  
Tectonically Active ◽  
Roer Valley Graben ◽  
Stratigraphic Position ◽  
Neogene Sediments ◽  
Geological Map ◽  
Sand Deposit ◽  
Seismic Sections ◽  
Drill Holes

The present geological map of the Flemish Region shows a small lens-shaped isolated outcrop of the Miocene Bolderberg, Diest and Kasterlee Formations, surrounded by younger formations, in an area that coincides with the tectonic Bree Uplift segment, on the southwestern border of the Roer Valley Graben in NE Limburg. The fault, bordering the segment at its SW side, had been interpreted to be tectonically active throughout the Neogene. Now, it is argued that an erroneous lithostratigraphic interpretation of the outcropping strata supported that view. Field observations of some of the outcrops and sampled drill holes show that the sediments do not belong to an Opitter member of the Bolderberg Formation, a Gruitrode Mill member of the Diest Formation and a Dorperberg member of the Kasterlee Formation, but most probably to the lower, latest Miocene or early Pliocene part of the Mol Formation and an unknown Pliocene marginal marine deposit not unlike and at about the stratigraphic position of the Poederlee Formation. That glauconiferous sand deposit, which has always been interpreted as consisting of two successive sedimentary cycles, is now accommodated in a single cycle, using the sedimentary model of deposition in a confined, backbarrier tidal basin subject to marine sand input and local stages of flow constriction and intraformational incision. Like already proposed by Rossa (1986) and Demyttenaere (1989), reprocessed seismic sections show only minor movements along the southwestern fault of the Bree Uplift since the Paleocene, and no inverse tectonic movements at all since the Middle Miocene.

scholarly journals The Diest Formation: a review of insights from the last decades

2020 ◽  
Vol 23 (3-4) ◽  
Author(s):  
RIK HOUTHUYS ◽  
RIEKO ADRIAENS ◽  
STIJN GOOLAERTS ◽  
Piet LAGA ◽  
STEPHEN LOUWYE ◽  
...  
Keyword(s):  
Driving Forces ◽  
Rhine River ◽  
Accommodation Space ◽  
Coastal Marine ◽  
Marine Sand ◽  
Roer Valley Graben ◽  
History Of ◽  
Dual Character ◽  
The 1960S ◽  
River Mouths

Research conducted since the 1960s on the upper Miocene Diest Formation in NE Belgium is reviewed and integrated. Their lithology unites the deposits of the glauconiferous Diest Sand in one formation, though biozones and internal sedimentary structures strongly suggest the formation may agglomerate the deposits of two separate, successive sedimentary cycles. The lowermost cycle is thought to have deposited the "Hageland Diest sand" during the early or middle Tortonian. It contains the Diest Sand in the main outcrop area in Hageland, Zuiderkempen and central Limburg, and probably also the Deurne Member near the city of Antwerpen. It furthermore includes the lower part of the Dessel Member in the central Kempen and in the Belgian part of the Roer Valley Graben (RVG). The Hageland Diest cycle represents the infill of a large tidal inlet tributary to the southern North Sea bight, then situated over the southern Netherlands and the Lower Rhine embayment. The Hageland Diest sand has the composition of a marine deposit, yet the confined area of occurrence and the presence of tens of metres deep incisions at the base, set it apart. The confinement of the embayment, strong tides and a steady supply of coastal‐marine sand are invoked as the main driving forces that resulted in the distinctive geometry and internal architecture of the unit. The upper cycle is associated with the "Kempen Diest sand", which is found in the subsurface of the RVG and the Noorderkempen. It has a late Tortonian to earliest Messinian age with progressively younger ages occurring to the NW. It encompasses the upper part of the Dessel Member and the overlying, coarser Diest Sand, and correlates to most or all of the thickly developed Diessen Formation in The Netherlands. It is the deposit of a prograding marine delta, containing both marine components and continental components fed by the palaeo‐Meuse/Rhine river mouths. Accommodation space kept increasing during deposition, due to subsidence of the deposition area, especially inside the RVG but also in the Noorderkempen. Although there is a fair consensus on the above, many concrete points about the geometry and depositional history of the Diest Formation and even a definitive decision on its single or dual character remain to be sorted out. In addition, this review excludes the Flemish Hills sand and the Gruitrode Member from the Diest Formation.

scholarly journals Upper Ordovician conodont biostratigraphy and revised lithostratigraphy and geological map, Akpatok Island, Ungava Bay, Nunavut

2018 ◽  
Vol 55 (1) ◽  
pp. 52-69 ◽  
Author(s):  
Shunxin Zhang
Keyword(s):  
Information Systems ◽  
Geographic Information Systems ◽  
Geographic Information ◽  
Field Observations ◽  
Limited Data ◽  
Upper Ordovician ◽  
Conodont Biostratigraphy ◽  
Stratigraphic Position ◽  
Geologic Map ◽  
Geological Map

Stratigraphic units exposed on Akpatok Island, Ungava Bay, Nunavut, were previously recognized as Boas River and Akpatok formations; their biostratigraphic ages and correlations, in particular the stratigraphic position and age of the organic rich “Boas River” Formation, were largely based on limited data. New detailed field observations have recognized three stratigraphic units, namely the Amadjuak, Akpatok, and Foster Bay formations, in which extensive microfossil sampling recovered over 22 000 conodont elements from 66 productive samples from both outcrops and rubble at over 20 localities in four areas. Four Upper Ordovician conodont zones and one unzoned interval are established for the three redefined formations: Belodina confluens and Oulodus velicuspis Interval zones are confined to the exposed Amadjuak Formation and correlated to Edenian and Maysvillian; Amorphognathus ordovicicus – Plegagnathus dartoni Concurrent-range Zone occurs with the Akpatok Formation and correlated to lower Richmondian; Rhipidognathus symmetricus Taxon-range Zone is retained in the Foster Bay Formation and correlated to upper Richmondian; and an “Unzoned Interval” is defined between the last two zones in the lower Foster Bay Formation. The conodont Amorphognathus ordovicicus occurs in both Akpatok and lower Foster Bay formations, and it is also recovered from the bituminous, argillaceous limestone rubble, based on which the stratigraphic position of the previously named “Boas River” Formation is most likely positioned within the lower Foster Bay Formation. The biostratigraphy and lithostratigraphy are combined with geographic information systems (GIS) to establish the thicknesses of the three formations and revise the geologic map of the island.

scholarly journals Subsurface structure of the Netherlands - results of recent onshore and offshore mapping

2006 ◽  
Vol 85 (4) ◽  
pp. 245-276 ◽  
Author(s):  
E.J.T. Duin ◽  
J.C. Doornenbal ◽  
R.H.B. Rijkers ◽  
J.W. Verbeek ◽  
Th.E. Wong
Keyword(s):  
The Netherlands ◽  
Cross Sections ◽  
Late Jurassic ◽  
Tectonic Setting ◽  
Tectonic Activity ◽  
Late Permian ◽  
Structural Elements ◽  
Depth Maps ◽  
Tectonically Active ◽  
Roer Valley Graben

AbstractThis paper presents depth maps for eight key horizons and seven thickness maps covering the onshore and offshore areas for the Late Permian to recent sedimentary section of the Netherlands. These maps, prepared in the context of a TNO regional mapping project, are supported by nine regional structural cross sections and a table summarizing the timing of tectonic activity from Carboniferous to recent. These new regional maps enable the delineation of various structural elements but also reveal the development of these elements through time with improved detail. Since the latest Carboniferous the tectonic setting of the Netherlands changed repeatedly. During successive tectonic phases several pre-existing structural elements were reactivated and new elements appeared. The various identified regional structural elements are grouped into six tectonically active periods: Late Carboniferous, Permian, Triassic, Late Jurassic, Late Cretaceous and Cenozoic. This study demonstrates that many structural elements and fault systems were repeatedly reactivated and that a clear distinction exists between long-lived elements, such as the Roer Valley Graben, and short-lived structural elements, such as the Terschelling Basin.

The oldest beaver from the Netherlands

2011 ◽  
Vol 90 (4) ◽  
pp. 311-314 ◽  
Author(s):  
W. Wessels ◽  
J. Frieling ◽  
R. Fraaije
Keyword(s):  
The Netherlands ◽  
North Sea ◽  
Castor Fiber ◽  
River Systems ◽  
Early Pliocene ◽  
The North ◽  
Marine Sand ◽  
The North Sea ◽  
Sand Deposit ◽  
Lower Molar

AbstractA lower molar of Castor fiber from the sandpit of Langenboom (the Netherlands) represents, so far, the oldest occurrence of a beaver in the North Sea Basin. Its presence in the marine sand deposit of the Langenboom Formation indicates that Castor fiber inhabited areas in or near the river systems of Rhine and Meuse in the Early Pliocene.

Understanding the Propagation of Nonuniform Corrosion on a Steel Surface Covered by Marine Sand

CORROSION ◽  
10.5006/3278 ◽  
2019 ◽  
Vol 75 (12) ◽  
pp. 1487-1501 ◽  
Author(s):  
Limin He ◽  
Yunze Xu ◽  
Xiaona Wang ◽  
Yi Huang
Keyword(s):  
Steel Surface ◽  
Pipeline Steel ◽  
Diffusion Path ◽  
Mineral Deposit ◽  
Concentration Difference ◽  
Marine Sand ◽  
Covered Area ◽  
Bare Steel ◽  
Sand Deposit ◽  
Deposit Layer

The corrosion progression of X65 pipeline steel, which was partly covered by a mineral deposit layer, was investigated in oxygen-containing artificial seawater using a multielectrode array (MEA) and electrical resistance method. Results show that the deposit covered area would act as the anodes due to the oxygen concentration difference between the bare steel area and deposit covered area. The most serious corrosion would occur at the bare steel area which was close to the sand deposit due to the diffusion of the cations from the deposit covered area to the bare steel area, leading to the decrease of local pH. Once the diffusion path between the bare steel area and the deposit covered area was blocked, the bare steel area would act as a constant cathode, resulting in the formation of a protective calcium carbonate layer on the bare steel surface.

scholarly journals THE CHARACTERISTIC OF COASTAL SUBSURFACE QUARTENARY SEDIMENT BASED ON GROUND PROBING RADAR (GPR) INTERPRETATION AND CORE DRILLING RESULT OF ANYER COAST, BANTEN PROVINCE

2016 ◽  
Vol 28 (2) ◽  
pp. 31
Author(s):  
Kris Budiono
Keyword(s):  
Standard Penetration Test ◽  
Spatial Filter ◽  
Core Drilling ◽  
Sediment Deposits ◽  
Volcanic Deposit ◽  
Uppermost Layer ◽  
Correlation Result ◽  
Geological Map ◽  
Sand Deposit ◽  
Shallow Water Sediment

The study of characteristic of subsurfase Quatenary sediment of Anyer coast have been done by using the data of Ground Probing Radar (GPR) image, Surfacial Geological map around the coast and the result of core drilling. The GPR equipment which was used are GSSI SIR 20 system and GSSI Sub Echo 40 MHz antennas. The GPR data image have been processed by using Radan GSSI software, Window NTIM version. The processing including Stacking, Spatial Filter, Migration and Decompolution. The interpretation of GPR image was done by using the principle of GPR stratigraphy through recoqnize to the internal and external reflector such as reflector configuration, continoutas, reflection, amplitude, etc, Furthermore the interpretation result of GPR image are correlated with the surfacial geological map and core drilling result that have been done by previous researscher. Besed on that correlation result, the characteristic of subsurface Quatenary deposits of study area can be divided into 5 unit mainly unit A, B, C, D and E. Unit A is the uppermost layer which is charactized by clay layer and coral reff fragments. Below the unit A they are unit B, C, and D wich were characterized by intercalation between sand and clay, sand deposit or sandstone, loose to dense. This condition is shown by the SPT (Standard Penetration Test) which have range between 10 to 50 blows per 15 Cm. Based on the characteristic of GPR image and sediment deposits of core drilling, these sediment deposits are interpreted as coastal and shallow water sediment deposits. Unit E is the lowermost layer which is interpreted as volcanic deposit. Keywords: subsurface quatenary sediment, ground propbing radar, core drilling, Anyer coast. Penelitian karakteristik sedimen bawah permukaan Kuarter di kawasan pantai Anyer telah dilakukan dengan mempergunakan data citra “ Ground Probing Radar”, geologi permukaan di sekitar kawasan pantai dan data hasil pemboran inti. Peralatan GPR yang dipergunakan adalah sistim SIR 20 GSSI dan antenna MLF 3200 GSSI.Data citra GPR telah diproses dengan mempergunakan perangkat lunak RADAN GSSI versi window NTIM. Pemrosesan terdiri dari “Stacking”, “Spatial Filter”, “Migration” dan “Decompolution”. Penafsiran Citra GPR dilakukan dengan mempergunakan prinsip Stratigrafi GPR melalui pengamatan terhadap internal dan eksternal reflector seperti konfigurasi reflector, kontinuitas, refleksi, amplitude dan lain-lain. Selanjutnya hasil penefsiran citra GPR ini dikorelasikan dengan peta geologi permukaan dan hasil pemboran inti yang telah dilakukan oleh peneliti terdahulu. Berdasarkan hasil korelasi tersebut karakteristik endapan Kuarter bawah permukaan daerah penelitian dapat dibagi menjadi 5 unit yaitu Unit A, B, C, D dan E. Unit A merupakan unit paling atas yang dicirikan lapisan lempung dan kerakal kerikil hasil rombakan koral. Unit B, C dan D berada di bawah ubit A yang merupakan endapan selang seling pasir dan lempung serta endapan pasir atau batu pasir bersifat urai sampai padat. Kondisi ini ditunjukan oleh hasil pengujian SPT(“Standard Penetration Test”) yang berkisar antara 10 sampai lebih dari 50 tumbukan per 15 Cm.Berdasarkan karakteristik fasies citra GPR dan endapan sedimen dari hasil pemboran inti, endapan sedimen tersebut ditafsirkan sebagai endapan pantai dan endapan laut dangkal Unit E merupakan lapisan paling bawah yang ditafsirkan sebagai endapan gunung api. Kata kunci: Sedimen Kuarter bawah permukaan,”Ground Probing Radar”, pemboran inti, pantai Anyer

Variations in Surface Textures of Quartz Sand using Electron Microscopy

1970 ◽  
Vol 28 ◽  
pp. 494-495
Author(s):  
Eugene J. Amaral
Keyword(s):  
Electron Microscopy ◽  
Glass Industry ◽  
Glass Slide ◽  
Distilled Water ◽  
Early Paleozoic ◽  
Secondary Effects ◽  
Surface Textures ◽  
High Silica ◽  
Sand Deposit ◽  
The U.S

Examination of sand grain surfaces from early Paleozoic sandstones by electron microscopy reveals a variety of secondary effects caused by rock-forming processes after final deposition of the sand. Detailed studies were conducted on both coarse (≥0.71mm) and fine (=0.25mm) fractions of St. Peter Sandstone, a widespread sand deposit underlying much of the U.S. Central Interior and used in the glass industry because of its remarkably high silica purity.The very friable sandstone was disaggregated and sieved to obtain the two size fractions, and then cleaned by boiling in HCl to remove any iron impurities and rinsed in distilled water. The sand grains were then partially embedded by sprinkling them onto a glass slide coated with a thin tacky layer of latex. Direct platinum shadowed carbon replicas were made of the exposed sand grain surfaces, and were separated by dissolution of the silica in HF acid.

Preparation of integrated circuits for TEM electromigration in situ studies

1986 ◽  
Vol 44 ◽  
pp. 882-883
Author(s):  
J. V. Maskowitz ◽  
W. E. Rhoden ◽  
D. R. Kitchen ◽  
R. E. Omlor ◽  
P. F. Lloyd
Keyword(s):  
Integrated Circuits ◽  
Crystallographic Orientation ◽  
Silicon Wafers ◽  
Minimum Size ◽  
Test Vehicle ◽  
In Situ Studies ◽  
Boron Doped ◽  
Doped Silicon ◽  
Drill Holes

The fabrication of the aluminum bridge test vehicle for use in the crystallographic studies of electromigration involves several photolithographic processes, some common, while others quite unique. It is most important to start with a clean wafer of known orientation. The wafers used are 7 mil thick boron doped silicon. The diameter of the wafer is 1.5 inches with a resistivity of 10-20 ohm-cm. The crystallographic orientation is (111).Initial attempts were made to both drill and laser holes in the silicon wafers then back fill with photoresist or mounting wax. A diamond tipped dentist burr was used to successfully drill holes in the wafer. This proved unacceptable in that the perimeter of the hole was cracked and chipped. Additionally, the minimum size hole realizable was > 300 μm. The drilled holes could not be arrayed on the wafer to any extent because the wafer would not stand up to the stress of multiple drilling.

Probabilistic evaluation of detection capability of eddy current testing to inspect pitting on a stainless steel clad using multiple signal features

2020 ◽  
Vol 64 (1-4) ◽  
pp. 47-55
Author(s):  
Takuma Tomizawa ◽  
Haicheng Song ◽  
Noritaka Yusa
Keyword(s):  
Stainless Steel ◽  
Eddy Current ◽  
Pressure Vessels ◽  
Eddy Current Testing ◽  
Probability Of Detection ◽  
Current Testing ◽  
Multiple Signal ◽  
Signal Features ◽  
Inner Surface ◽  
Drill Holes

This study proposes a probability of detection (POD) model to quantitatively evaluate the capability of eddy current testing to detect flaws on the inner surface of pressure vessels cladded by stainless steel and in the presence of high noise level. Welded plate samples with drill holes were prepared to simulate corrosion that typically appears on the inner surface of large-scale pressure vessels. The signals generated by the drill holes and the noise caused by the weld were examined using eddy current testing. A hit/miss-based POD model with multiple flaw parameters and multiple signal features was proposed to analyze the measured signals. It is shown that the proposed model is able to more reasonably characterize the detectability of eddy current signals compared to conventional models that consider a single signal feature.

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