Trackline chart, bathymetric and seismic profiles acquired on R/V Lee Cruise 9-78-HW, near Hawaii

1979 ◽  
Author(s):  
William R. Normark ◽  
J.G. Moore ◽  
P.W. Lipman ◽  
J. D. Young
Keyword(s):  
Author(s):  
Homayoun Khoshravan ◽  
Homayoun Khoshravan

The main goal of the research is to analyze the global warming impact on Urmia lake vulnerabiliy and hazard. By the study of topographic maps, satellite images and field research, the various types of coasts were identified: mud flats, salt marshes, sandy or cliffed coasts, and islands. Moreover the interpretation of seismic profiles, has led to recognize so important morphological features in the lake bed, such as: erosive channels, colos, mud volcanoes, the raised sandy masses and under water mounts. The main results illustrate the variable morphological behavior of Urmia Lake in different parts of the lake.


2011 ◽  
Vol 3 (Special Issue) ◽  
pp. 1-7
Author(s):  
A. A. Prokofyev ◽  
O. L. Kuskov ◽  
V. A. Kronrod

2021 ◽  
Vol 11 (14) ◽  
pp. 6300
Author(s):  
Igor Smolyar ◽  
Daniel Smolyar

Patterns found among both living systems, such as fish scales, bones, and tree rings, and non-living systems, such as terrestrial and extraterrestrial dunes, microstructures of alloys, and geological seismic profiles, are comprised of anisotropic layers of different thicknesses and lengths. These layered patterns form a record of internal and external factors that regulate pattern formation in their various systems, making it potentially possible to recognize events in the formation history of these systems. In our previous work, we developed an empirical model (EM) of anisotropic layered patterns using an N-partite graph, denoted as G(N), and a Boolean function to formalize the layer structure. The concept of isotropic and anisotropic layers was presented and described in terms of the G(N) and Boolean function. The central element of the present work is the justification that arbitrary binary patterns are made up of such layers. It has been shown that within the frame of the proposed model, it is the isotropic and anisotropic layers themselves that are the building blocks of binary layered and arbitrary patterns; pixels play no role. This is why the EM can be used to describe the morphological characteristics of such patterns. We present the parameters disorder of layer structure, disorder of layer size, and pattern complexity to describe the degree of deviation of the structure and size of an arbitrary anisotropic pattern being studied from the structure and size of a layered isotropic analog. Experiments with arbitrary patterns, such as regular geometric figures, convex and concave polygons, contour maps, the shape of island coastlines, river meanders, historic texts, and artistic drawings are presented to illustrate the spectrum of problems that it may be possible to solve by applying the EM. The differences and similarities between the proposed and existing morphological characteristics of patterns has been discussed, as well as the pros and cons of the suggested method.


1990 ◽  
Vol 177 (1-3) ◽  
pp. 15-37 ◽  
Author(s):  
C. Bois ◽  
J.-P. Lefort ◽  
B. Le Gall ◽  
J.-C. Sibuet ◽  
O. Gariel ◽  
...  
Keyword(s):  

Geophysics ◽  
1992 ◽  
Vol 57 (4) ◽  
pp. 543-553 ◽  
Author(s):  
Christopher P. Ross

Amplitude versus offset (AVO) measurements for deep hydrocarbon‐bearing sands can be compromised when made in close proximity to a shallow salt piercement structure. Anomalous responses are observed, particularly on low acoustic impedance bright spots. CMP data from key seismic profiles traversing the bright spots do not show the expected Class 3 offset responses. On these CMPs, significant decrease of far trace energy is observed. CMP data from other seismic profiles off‐structure do exhibit the Class 3 offset responses, implying that structural complications may be interfering with the offset response. A synthetic AVO gather was generated using well log data, which supports the off‐structure Class 3 responses, further reinforcing the concept of structurally‐biased AVO responses. Acoustic, pseudo‐spectral modeling of the structure substantiates the misleading AVO response. Pseudo‐spectral modeling results suggest that signal degradation observed on the far offsets is caused by wavefield refraction—a shadow zone, where the known hydrocarbon‐bearing sands are not completely illuminated. Such shadow zones obscure the correct AVO response, which may have bearing on exploration and development.


2021 ◽  
Author(s):  
Alessandra Lanzoni ◽  
Anna Del Ben ◽  
Edy Forlin ◽  
Federica Donda ◽  
Massimo Zecchin

<p>The Adriatic basin represents one of several restricted basins located in the Mediterranean Area. It consists of the foreland of three different orogenic belts: the Dinarides to the East, active during the Eocene, the Southern Alps to the North, active since the Cretaceous time, and the Apennines to the West, active since the Paleogene. The Apennines had a primary role during the Messinian Salinity Crisis (MSC), conditioning the connection between the Adriatic basin, the Ionian basin, and the proto-Tyrrhenian basin. During the Messinian, the present Adriatic Sea was characterized by shallow water domains, where gypsum evaporites initially deposited and often successively incised or outcropped. </p><p>In the past 50 years, a massive dataset, composed of 2D multichannel seismic data and boreholes, was collected, covering almost the whole Adriatic basin in the Italian offshore. In this work, we interpreted the Plio-Quaternary base (PQb), based on available public datasets and on seismic profiles present in literature, which provided regional information from the northernmost Trieste Gulf (Northern Adriatic Sea) to the Otranto Channel (Southern Adriatic Sea). Here, we propose the PQb time-structural map, obtained by analyzing more than 600 seismic profiles. The PQb represents both the Messinian erosion and/or the top of the Messinian evaporites. It is characterized by a high-amplitude reflector, commonly called “horizon M” in the old literature. Principal findings concerning the Messinian event are summarized as below: </p><p>-The Northern Adriatic (Gulf of Trieste, Gulf of Venice, Po delta, Kvarner Area) reveals widespread channelized systems produced by the initial decrease of the sea level, followed by subaerial erosion, related to further sea level decrease. High-grade erosion involved the nearby Adriatic carbonate platform in the Croatian offshore, where deep valleys, filled with Last Messinian or post- Messinian sediments, cut through the limestones.</p><p>-The Central Adriatic (from the Po delta to the Gargano Promontory) displays a higher evaporites accumulation than the northern sector. Meanwhile, the Mid-Adriatic Ridge was already developing, along with the Apennine Chain, which was in a westernmost position. Erosional features in the deeper area are related to channelized systems, which followed the evaporites deposition. Meanwhile, also the Mid-Adriatic Ridge was affected by erosion.</p><p>-The Southern Adriatic (from the Gargano Promontory to the Otranto Channel) is characterized by the Mesozoic Apulia carbonate platform, covered by a thin Cenozoic sequence affected by subaerial erosion or non-deposition. The platform margin and the slope leading to the deepest South Adriatic basin, where a Messinian gypsum layer, also recorded in the Albanian and Croatian offshore, shows a lower level of upper erosion.</p><p>In general, we notice strongly variable thicknesses of the horizon M, which is related to submarine erosion (channels), subaerial erosion (discontinuous surfaces), non-deposition (possible unconformity), and tilting toward the surrounding chains (deepening horizons). In this work, we evaluate these different components from a regional point of view.  </p>


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