scholarly journals Evidence of Unknown Paleo-Tsunami Events along the Alas Strait, West Sumbawa, Indonesia

Geosciences ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 46
Author(s):  
Bachtiar W. Mutaqin ◽  
Franck Lavigne ◽  
Patrick Wassmer ◽  
Martine Trautmann ◽  
Puncak Joyontono ◽  
...  
Keyword(s):  
Radiocarbon Dating ◽  
Pyroclastic Flows ◽  
Western Coast ◽  
Eastern Shore ◽  
Tsunami Deposits ◽  
The West ◽  
Marine Deposits ◽  
Sedimentary Records ◽  
The North ◽  
Large Earthquakes

Indonesia is exposed to earthquakes, volcanic activities, and associated tsunamis. This is particularly the case for Lombok and Sumbawa Islands in West Nusa Tenggara, where evidence of tsunamis is frequently observed in its coastal sedimentary record. If the 1815 CE Tambora eruption on Sumbawa Island generated a tsunami with well-identified traces on the surrounding islands, little is known about the consequences of the 1257 CE tremendous eruption of Samalas on the neighboring islands, and especially about the possible tsunamis generated in reason of a paucity of research on coastal sedimentary records in this area. However, on Lombok Island, the eruption of the Samalas volcano produced significant volumes of pyroclastic flows that entered the sea in the North and East of the island. These phenomena must have produced a tsunami that left their traces, especially on Sumbawa Island, whose western coastline is only 14 km away from Lombok’s eastern shore. Therefore, the main goal of this study is to investigate, find evidence, and determine the age of marine-origin sediments along the shore of the Alas Strait, Indonesia. We collected and analyzed samples of coral and seashells from marine deposits identified along the west coast of Sumbawa, i.e., in Belang Island and abandoned fishponds in Kiantar Village, in order to identify the sources and the occurrence period of these deposits events. Based on the radiocarbon dating of coral and seashell samples, we concluded that none of the identified marine deposits along the western coast of Sumbawa could be related chronologically to the 1257 CE eruption of Samalas. However, possible tsunami deposits located in Belang Island and abandoned fishponds in Kiantar Village yielded 4th century CE, 9th century CE, and 17th century CE. We also conclude that past large earthquakes triggered these tsunamis since no known volcanic eruption occurred near the Alas Strait at that time that may have triggered a tsunami.

Stratigraphy and timing of eolianite deposition on Rottnest Island, Western Australia

2003 ◽  
Vol 60 (2) ◽  
pp. 211-222 ◽  
Author(s):  
Paul J. Hearty
Keyword(s):  
North Atlantic ◽  
Late Quaternary ◽  
The West ◽  
Oxygen Isotope Stage ◽  
Amino Acid Racemization ◽  
Marine Deposits ◽  
The North ◽  
The North Atlantic ◽  
Radiometric Ages ◽  
Mis 5E

AbstractOver 100 whole-rock amino acid racemization (AAR) ratios from outcrops around Rottnest Island (32.0° S Latitude near Perth) indicate distinct pulses of eolian deposition during the late Quaternary. Whole-rock d-alloisoleucine/l-isoleucine (A/I) ratios from bioclastic carbonate deposits fall into three distinct modal classes or “aminozones.” The oldest, Aminozone E, averages 0.33 ± 0.04 (n = 21). Red palaeosol and thick calcrete generally cap the Aminozone E deposits. A younger Aminozone C averages 0.22 ± 0.03 (n = 63); comprising two submodes at 0.26 ± 0.01 (n = 14) and 0.21 ± 0.02 (n = 49). Multiple dune sets of this interval are interrupted by relatively weak, brown to tan “protosols.” A dense, dark brown rendzina palaeosol caps the Aminozone C succession. Ratios from Holocene dune and marine deposits (“Aminozone A”) center on 0.11 ± 0.02 (n = 15), comprising submodes of 0.13 ± 0.01 (9) and 0.09 ± 0.01 (6). Calibration of A/I averages from Aminozones E and A are provided by U/Th and 14C radiometric ages of 125,000 yr (marine oxygen isotope stage (MIS) 5e and 2000–6000 14C yr B.P. (MIS 1), respectively. The whole-rock A/I results support periodic deposition initiated during MIS 5e, continuing through MIS 5c, and then peaking at the end of MIS 5a, about 70,000–80,000 yr ago. Oceanographic evidence indicates the area was subjected to much colder conditions during MIS 2–4 (10,000 to 70,000 yr ago), greatly slowing the epimerization rate. Eolianite deposition resumed in the mid Holocene (∼6000 yr ago) up to the present. The A/I epimerization pathway constructed from Rottnest Island shows remarkable similarity to that of Bermuda in the North Atlantic (32° N Latitude). These findings suggest that, like Bermuda, the eolian activity on Rottnest occurred primarily during or shortly after interglacial highstands when the shoreline was near the present datum, rather than during glacial lowstands when the coastline was positioned 10–20 km to the west.

The Late Cenozoic evolution of the Aksu basin (Isparta Angle; SW Turkey). New insights

2011 ◽  
Vol 182 (2) ◽  
pp. 133-148 ◽  
Author(s):  
André Poisson ◽  
Fabienne Orszag-Sperber ◽  
Erdal Kosun ◽  
Maria-Angella Bassetti ◽  
Carla Müller ◽  
...  
Keyword(s):  
Coral Reefs ◽  
Normal Faults ◽  
The West ◽  
Shallow Marine ◽  
Northern Margin ◽  
Sea Level Fluctuations ◽  
Marine Deposits ◽  
The North ◽  
Sw Turkey ◽  
Isparta Angle

Abstract The Mio-Pliocene basins around the Antalya gulf in SW Turkey developed above the Tauric Mesozoic platforms on which the Antalya nappes had been thrusted (in Late Cretaceous-Paleocene times). The closure of the initial Isparta Angle during these events (E-W compression) initiated the N-S orientation of the main structural lines, which persisted later and explains the orientation of the Aksu basin in contrast with the E-W orientation of the eastern Neo-gene Mediterranean basins. The area, and all southwestern Turkey, became emergent at the end of the Oligocene and were the site of shallow-marine carbonate deposits in the Chattian-Aquitanian, giving way to the wide Lycian basin in Burdigalian-Langhian times. The progressive emplacement of the Lycian nappes from the north over this basin provoked first its subsidence and then its emersion when the nappes attained their final position over the Bey Daglari platform in Langhian times. Coinciding, or in response to the Lycian nappes emplacement, the Aksu basin was initiated as an elongated N-S graben which was filled by thick accumulations of terrestrial and marine deposits(including coral reefs), which derived from the erosion of the Lycian allochton and its basement (Langhian?, Serravallian and Tortonian times). The syn-sedimentary tectonics : reactivation of the normal faults along the west margin of the basin, the continuous uplift of the neighbouring continental areas (beginning of the Aksu thrust), governed the geometry of the basin. As a result and due to the uplift of its northern margin, the Aksu basin migrated towards the south and in Messinian times it was reduced to a narrow gulf along the eastern margin of which the Gebiz limestones were deposited as fringing coral reefs. The age of these limestones has been debated. Our new data allow us to attribute them to the Messinian. The drastic retreat of the sea at the end of this period, provoked the erosion of large parts of the Messinian deposits and the formation of deep canyons on land and under the sea down to the Antalya abyssal plain, in which evaporites were deposited. During the Zanclean transgression, the Eskiköy-Kargi canyon was filled by coarse clastics of a Gilbert delta derived from the northern continental area following a model well known elsewhere in the Mediterranean basins. Southward, shallow-marine sands and marls unconformably cover the remnants of the Messinian deposits and the emergent areas of the southern Antalya gulf. After Zanclean times (end of Pliocene?), the Aksu basin was deformed, due to the west-directed Aksu compressional event (end of the Aksu thrust). Quaternary terraces of the Aksu river at various altitudes, as well as the terraces of the Antalya tufa can be related to sea level fluctuations.

scholarly journals 4. Recent Observations on the direction of the Striæ on Rocks and Boulders.

1857 ◽  
Vol 3 ◽  
pp. 121-122
Author(s):  
James Smith
Keyword(s):  
East Coast ◽  
Western Coast ◽  
Present Position ◽  
The West ◽  
Moving Force ◽  
The North ◽  
Erratic Block

Mr Smith of Jordanhill next read a paper on the direction of the striae on rocks and boulders in the West of Scotland.It had generally been supposed that the cause, whatever it was, which lodged the erratic block beds in their present position had proceeded from the north and west.This was true with respect to the basin of the Clyde and the east coast of Scotland; but on the western coast of Argyllshire, at Loch Crinan and Appin he had observed that the strike side (stoss seite) of the rocks pointed to the east, and the lee side (lee seite) to the west, shewing that, in these cases, the direction of the moving force was from east to west.

scholarly journals ‘The Wool Road’ of the Late Bronze Age: Cultural, Geographical, and Chronological Context

2021 ◽  
pp. 23-38
Author(s):  
Natal'ya Shishlina
Keyword(s):  
Eastern Europe ◽  
Bronze Age ◽  
Radiocarbon Dating ◽  
Innovative Technology ◽  
Northern Eurasia ◽  
The West ◽  
The North ◽  
Wool Textile ◽  
South Siberia ◽  
The Bronze Age

Innovative technologies for new products and consumption, a secondary product revolution, have dramatically changed the course of the Bronze Age economic transformations. Changes included introduction of an innovative technology of wool production and it’s spread among the Northern Eurasia population during 3000–2000 BC. Sophisticated methods of studying the ancient wool textile obtained from the Bronze Age sites of Northern Eurasia, i.e. technological analyses, radiocarbon dating, and the identification of the isotope signature preserved in the wool textile, made it possible not only to discuss the time the wool fiber appeared in the Bronze Age textile production and to determine the cultural context and areas but also to discuss a new hypothesis on the formation of so called Wool Road in early 2nd millennium BC – a route that connected the foothills, forest-steppe, and forest regions of Eastern Europe in the West and South Siberia and China in the East. The discovery of wool textiles and their radiocarbon dating clearly defines the spread of the innovative textile strategies out of the Near East from the South to the North, then from the North Caucasus Piedmont areas from the West to the East. The author suggests that one of the ways the wool textile spread to west was from the southern steppe region of Eastern Europe via the Black Sea steppes.

Petrographical Notes on the Rock-Specimens collected in the Little Island of Trinidad, S. Atlantic, by the Antarctic Expedition of 1839–43, under Sir James Clark Ross

1900 ◽  
Vol 12 (58) ◽  
pp. 317-323 ◽  
Author(s):  
G. T. Prior
Keyword(s):  
Atlantic Ocean ◽  
West Indies ◽  
South Atlantic Ocean ◽  
Western Coast ◽  
The West ◽  
The North ◽  
Antarctic Expedition ◽  
The Antarctic ◽  
North Western ◽  
Rock Specimens

The Little Island of Trinidad, as it is called to distinguish it from the larger island in the West Indies, is situated in the South Atlantic Ocean, about 700 miles off the coast of Brazil, in lat. 20°31' S. and long. 29°19' W.According to Ross, who in 1839 effeeted a landing on tile N.W. coast, the island is a mass of volcanic matter, the rocks of which it is composed assuming the most extraordinary shapes. The most remarkable of these are the Sugar Loaf Hill on the southern and the Nine-Pin Rock on the north-western coast.

scholarly journals Distribution of suspended matter off the western coast of the crimea under impact of the strong winds of various directions

2019 ◽  
pp. 74-88
Author(s):  
A. A. Aleskerovа ◽  
A. A. Kubryakov ◽  
Yu. N. Goryachkin ◽  
S. V. Stanichny ◽  
A. V. Garmashov
Keyword(s):  
Bottom Sediments ◽  
West Coast ◽  
Suspended Matter ◽  
Cold Water ◽  
Western Coast ◽  
Wave Impact ◽  
The West ◽  
The North ◽  
The Crimea ◽  
Strong Winds

The mechanisms of formation and distribution of total suspended matter (tsm) off the West Coast of Crimea under the influence of strong winds of various directions were investigated on the base of satellite data of medium and high resolution. The maximum tsm reaching the values of 200 mg / l was is observed during strong southern winds. In this case, the zone of high tsm is located at the western shelf of the Crimea limited by a 50 m isobath. The wave impact on resuspension of bottom sediments and the erosion of clay cliffs located on the west coast of Crimea lead to the formation of a large amount of tsm. After the storm, a northern alongshore current transfers tsm to the north. During northeast winds, the highest tsm are observed not near the coast, but in the seaward part of the shelf between 30 and 50 m isobaths. It is likely that turbulent mixing during such winds resuspense bottom sediments in shallow areas, which are further transported from the coast due to the offshore winds. The wind surge in this case leads to the formation of a band of clean cold water near the coast. A specific feature of the action of the northern and northwestern storms is the formation of a longshore jet stream along the western coast. The current occurs at the front of the upwelling zone. The stream transports the suspended matter offshore southward. The concentration of the suspended matter in this case is also much lower than when exposed to the southern winds, but it can reach a value of 3 mg/l.

Tectonic Criteria of Oil and GAS Potential at the Transitional Part of the Susha-sea Along the Western Coast of the South Caspian Depression

2021 ◽  
Author(s):  
Baylar Aslanov ◽  
Nurlan Jabizade ◽  
Arastun Khuduzadeh ◽  
Fidan Aslanzade
Keyword(s):  
Oil And Gas ◽  
Central Place ◽  
Western Coast ◽  
The South ◽  
The West ◽  
The North ◽  
Oil And Gas Fields ◽  
Caspian Depression ◽  
Offshore Oil And Gas ◽  
Gas Fields

Abstract The southern part of the South Caspian oil and gas Basin (SCB) is one of the main oil and gas producing regions in the central part of Eurasian continent. The large number of offshore oil and gas fields is located here, therefore the basin considered as a promising direction for the further perspective zones survey. The basin is located between the uneven-aged mountain structures of the Lesser and Greater Caucasus in the west, the Great Balkhan and Kopet-Dag in the east, the Talish and Elbrus ridges in the south. In the north, it is limited by a sub-latitudinal regional deep fault, which fixes the northern slope of the complex Absheron-Balkhan zone of uplifts, which is part of the South Kura and Western Turkmenistan depressions. Among the structural elements of the second order, the South Absheron depression, the complex Abikh swell and the Javadkhan-Natevan zone in the west should be noted; Turkmen terrace, Ogurchinskaya step and Chikishlyar-Fersmanovskaya-Weber-Western zone in the east (Fig. 1). The central place in the structure of the basin is occupied by the South Caspian Mega Depression (SCMD), in the most submerged part of which - the pre Elbrus Basin - the basement lies at a depth of about 25 km, and the sedimentary stratum, including Mesozoic, Cenozoic and Quaternary formations, is largely represented by the Pliocene - post-Pliocene sediments, reaching a total thickness of 8–10 km and more in the troughs (Fig. 2, 3).

scholarly journals Faulting and Folding of the Transgressive Surface Offshore Ventura Records Deformational Events in the Holocene

2021 ◽  
Vol 9 ◽  
Author(s):  
Hector Perea ◽  
Gülsen Ucarkus ◽  
Neal Driscoll ◽  
Graham Kent ◽  
Yuval Levy ◽  
...  
Keyword(s):  
Fault System ◽  
The West ◽  
The Holocene ◽  
Active Structures ◽  
The North ◽  
Transverse Ranges ◽  
Thrust System ◽  
Large Earthquakes ◽  
Age Estimates ◽  
The Last Glacial

Identifying the offshore thrust faults of the Western Transverse Ranges that could produce large earthquakes and seafloor uplift is essential to assess potential geohazards for the region. The Western Transverse Ranges in southern California are an E-W trending fold-and-thrust system that extends offshore west of Ventura. Using a high-resolution seismic CHIRP dataset, we have identified the Last Glacial Transgressive Surface (LGTS) and two Holocene seismostratigraphic units. Deformation of the LGTS, together with onlapping packages that exhibit divergence and rotation across the active structures, provide evidence for three to four deformational events with vertical uplifts ranging from 1 to 10 m. Based on the depth of the LGTS and the Holocene sediment thickness, age estimates for the deformational events reveal a good correlation with the onshore paleoseismological results for the Ventura-Pitas Point fault and the Ventura-Avenue anticline. The observed deformation along the offshore segments of the Ventura-Pitas Point fault and Ventura-Avenue anticline trend diminishes toward the west. Farther north, the deformation along the offshore Red Mountain anticline also diminishes to the west with the shortening stepping north onto the Mesa-Rincon Creek fault system. These observations suggest that offshore deformation along the fault-fold structures moving westward is systematically stepping to the north toward the hinterland. The decrease in the amount of deformation along the frontal structures towards the west corresponds to an increase in deformation along the hinterland fold systems, which could result from a connection of the fault strands at depth. A connection at depth of the northward dipping thrusts to a regional master detachment may explain the apparent jump of the deformation moving west, from the Ventura-Pitas Point fault and the Ventura-Avenue anticline to the Red Mountain anticline, and then, from the Red Mountain anticline to the Mesa-Rincon Creek fold system. Finally, considering the maximum vertical uplift estimated for events on these structures (max ∼10 m), along with the potential of a common master detachment that may rupture in concert, this system could generate a large magnitude earthquake (>Mw 7.0) and a consequent tsunami.

The Whittier Narrows, California Earthquake of October 1, 1987—Seismology

1988 ◽  
Vol 4 (1) ◽  
pp. 43-53 ◽  
Author(s):  
L. Jones ◽  
E. Hauksson
Keyword(s):  
Los Angeles ◽  
Los Angeles Basin ◽  
The West ◽  
Northern Margin ◽  
The North ◽  
Rupture Area ◽  
Largest Aftershock ◽  
Large Earthquakes ◽  
East West ◽  
Strike Slip Movement

The October 1, 1987 Whittier Narrows earthquake ( ML = 5.9) was located at 34° 3.0′N, 118° 4.8′W, at the northwestern end of the Puente Hills. The sequence ruptured a small part, 4 km by 5 km, of a previously unidentified, buried, thrust fault that strikes east-west and dips 25° down to the north. This fault may be part of a large system of thrust faults extending across the entire east-west length of the northern margin of the Los Angeles basin. The focus of the mainshock is deep, at 14 ± 1 km. The largest aftershock ( ML = 5.3) produced mostly strike-slip movement on a steeply dipping, northwest plane, that bounds the mainshock rupture area to the west. Enhancement of the Los Angeles basin seismic network would facilitate investigation of the potential of these faults for moderate-sized or large earthquakes.

scholarly journals Circulação de ar na península de Tróia e costa da Galé

Finisterra ◽  
2012 ◽  
Vol 35 (70) ◽  
Author(s):  
Carlos Silva Neto
Keyword(s):  
High Frequency ◽  
Air Flow ◽  
Warm Water ◽  
Western Coast ◽  
The West ◽  
Wind Speeds ◽  
The North ◽  
North Wind ◽  
The Difference

AIR FLOW OVER THE TRÓIA PENINSULA AND THE COSTA DA GALÉ – In the summer, the Portuguese western coast is characterised by an evident dominance of north and northwest wind directions. Due the influence of the Arrábida mountain, the north wind suffers a deflection and blows from the west, southwest or even south over the Tróia Peninsula, where in the summer months there is a high frequency of wind directions between west and south. This deflection is much more frequent and better marked at night than at daylight. At daylight the strong north wind is channelled through a valley between Palmela hill and the Louro mountain and frequently blows over the Tróia Peninsula, in directions between north-northeast and north-northwest. At night, north and northwest wind speeds are generally lower and west and south winds blow all over the Tróia Peninsula towards Carvalhal, as result of the deflection caused by the Arrábida and Cabo Espichel. The wind directions between west and south, frequent at night on the Tróia Peninsula, are also intensified by the difference of temperature between the cool ocean and the warm water of the estuary.

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