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Abstract The Santos Basin (SB) is the main petroliferous basin in the Brazilian continental margin and one of the most studied marine areas in Brazil. However, historical data suggest that new efforts should be carried out to acquire quantitative biological data, especially in the deep sea, to establish the baseline of essential ocean variables in different ecosystems for future monitoring programs. The Brazilian energy company Petrobras planned and executed 24 oceanographic cruises over a period of 2 years to assess the benthic (SANSED cruise) and pelagic (SANAGU cruise) systems of the SB (356 days at sea in 2019 and 2021/2022). These efforts were part of the Santos Project, which comprised a comprehensive environmental study aimed at investigating benthic and pelagic variables to characterize ecology, biogeochemistry, thermohaline properties of water masses, and ocean circulation patterns, geomorphology, and sedimentology, as well as organic and inorganic chemistry. Here we present the detailed sampling designs and the field methods employed on board, during the SB scientific cruises. All sampling protocols were based on standardized approaches. For the benthos analyses, triplicate sediment samples were performed using a GOMEX-type box corer (0.25 m²) or a large modified Van Veen grab (0.75 m²) at 100 stations ranging from 25 to 2400 m depth. At each station, 25 geochemical and physico-chemical parameters were analyzed in addition to micro-, meio-, and macrofauna and living foraminifera samples. For the pelagic system, 60 stations were selected to investigate the plankton community, ranging in size from pico- to macroplankton, through vertical, horizontal, and oblique net hauls (20, 200, and 500 μm mesh size), as well as 25 biogeochemical parameters collected with an aid of a CTD-rosette sampler. Part of this scientific information also serves the Regional Environmental Characterization Project (PCR-BS) in support of Petrobras’ Santos Basin drilling licensing process led by the Brazilian Environmental Agency – IBAMA. This project contributes to the sustainable development of the SB, in line with the guidelines of the United Nations Decade of Ocean Science for Sustainable Development.

We have shown that the Paramagnetic Meissner Effect (PME) is directly associated with pinning, and not necessarily related to the presence of pi-junctions. Through the study of the magnetic properties of two-dimensional Josephson junction arrays (2D-JJA) in the present work we show that, among the systems exhibiting PME, only those with suffciently low dissipation and high capacitance will show dynamics reentrance. The concept of a critical state and its use in the interpretation of AC magnetization data in terms of a critical current density were introduced to derive the magnetic properties of hard type-II superconductors. In the critical state model proposed by Bean, flux lines penetrate into the sample and, due to the presence of disorder they give rise to a steady flux gradient. Here we show that in 2D-JJA this typical picture is valid only in short-range distances. For long-range distances, the picture of uniform flux fronts, as described by a critical state model, breaks down and the penetration of the magnetic field takes place through the growth of magnetic dendrites. De Gennes originally compared the slope of a pile of vortices to a sand-pile, with the slope being proportional to the local magnitude of the critical current. Dynamical properties of the sand-pile problem have attracted new attention since it consists of a marginally stable system displaying self-organized criticality (SOC). In this case, when a superconductor is in the Bean critical state, the addition of vortices occurs by increasing the external magnetic field. This procedure is analogous to the introduction of new grains to a sand-pile and is expected to produce an avalanche of grains of sand (or, equivalently, vortices) of all sizes to maintain a constant gradient in the grain (or, magnetic ux) density. We show in this work strong evidences pointing out that, for some specific conditions, magnetic field penetrates 2D-JJA in ux avalanches.

Index code	Element
ti	article title
au	author
kw	article keywords
subject	subject (title words, abstract and keywords)
ab	abstract
ta	journal short title (e.g. Cad. Saúde Pública)
journal_title	journal full title (e.g. Cadernos de Saúde Pública)
la	publication language code (e.g. pt - Portuguese, es - Spanish)
type	document type
pid	publication identifier
publication_year	publication year of publication
sponsor	sponsor
aff_country	country code of the author's affiliation
aff_institution	author affiliation institution
volume	article volume
issue	article issue
elocation	elocation
doi	DOI number
issn	journal ISSN
in	SciELO colection code (e.g. scl - Brasil, col - Colômbia)
use_license	article usage license code

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