A new artificial reef design for octopus (Octopus vulgaris cuvier, 1797) in the Aegean sea and preliminary results

The paleoenviromental conditions during the depositional interval of sapropel S1 in the northeastern Aegean (gravity core M-4, length 2.53 m; south Limnos basin) are studied based on quantitative micropaleontological (benthic and planktonic foraminifera) and geochemical (OC, δ13Corg) analyses. Special feature of core M-4 is the thickness of S1 layer (96 cm). Our study points that sapropelic layer S1a has been deposited in more dysoxic and warmer conditions in respect to S1b. Both primary productivity and preservation of organic material are more intense during the lower part of S1. An interruption of the sapropelic conditions at 8.0 Ka BP which is mainly characterized by the increase of agglutinated foraminiferal forms confirms both higher oxygen bottom conditions and freshwater input.

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Hemocyanin levels in Octopus vulgaris and the cuttlefish Sepia officinalis from the aegean sea

Comparative Biochemistry and Physiology Part A Physiology ◽

10.1016/0300-9629(88)90638-x ◽

1988 ◽

Vol 91 (3) ◽

pp. 581-585 ◽

Cited By ~ 13

Author(s):

N.M Senozan ◽

Ahmet Avinc ◽

Zehra Unver

Keyword(s):

Aegean Sea ◽

Octopus Vulgaris ◽

Sepia Officinalis

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A new VLF radio receiver in Greece for the detection of lower ionosphere anomalies before strong seismic events and the preliminary results for a strong (6.7 Mw) earthquake that occurred in Samos (Greece) on 30/10/2020.

10.5194/egusphere-egu21-12516 ◽

2021 ◽

Author(s):

Dimitrios Politis ◽

Stelios Potirakis ◽

Sagardweep Biswas ◽

Sudipta Sasmal ◽

Masashi Hayakawa

Keyword(s):

Fresnel Zone ◽

Focal Depth ◽

Lower Ionosphere ◽

Aegean Sea ◽

Propagation Path ◽

Radio Receiver ◽

Preliminary Results ◽

Amplitude Data ◽

Recorded Data ◽

The University

A new VLF/LF (10 - 47.5 kHz) radio receiver has recently been installed in the University of West Attica, in Athens (Greece), and has been operating in trial mode since April 2020 for the study of sub-ionospheric propagation variations, mainly aiming at the identification of possible earthquake (EQ) precursors or signatures of other extreme geophysical phenomena. The receiver is monitoring signals from a number of transmitters. Most of them are located in Europe, while some are located in Asia, Australia and North America. The recorded data (amplitude and phase) from this receiver are sampled at a rate of 1 sample per second. In this paper we present information about the new VLF/LF receiver as well as preliminary results concerning a very recent, strong (Mw = 6.7), shallow (focal depth = 12 km), EQ that occurred in Greece (epicenter located in the Aegean Sea, off-coast of the Samos island, close to the Greece-Turkey borders) on 30/10/2020, hereafter referred to as Samos&#8217; EQ. The subionospheric propagation data associated with two specific transmitters were analyzed. &#932;he first transmitter, with call sign TBB, is located in Denizk&#246;y (Turkey) and the location of Samos&#8217; EQ epicenter is within of 5th Fresnel zone of the corresponding propagation path. The second transmitter, with call sign ISR, is located in Negev (Israel) and the location of Samos&#8217; EQ epicenter is in close distance to the borders of the 5th Fresnel zone, so that, considering the magnitude of the specific EQ, the corresponding propagation path could possibly be disturbed. In this paper we present the analysis of the receiver&#8217;s amplitude data by means of the Terminator Time Method (TTM) in order to reveal any possible pre-seismic anomaly in the lower ionosphere. Our preliminary results show that there are indications for disturbance of the lower ionosphere a few days before the EQ occurrence.

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