@InProceedings{CabralVianGher:1991:GlChEf,
author = "Cabral, Alexandre Pereira and Vianna, Marcio Luiz and Gherardi,
Douglas Francisco Marcolino",
title = "Global Change Effects on Early Holocene Sedimentation of the
Brazilian Continental Shelf Determined from TM-LANDSAT 5 data of
the Seafloor",
booktitle = "Proceedings...",
year = "1991",
pages = "935--946",
organization = "International Symposium on Remote Sensing of Environment, 24.",
publisher = "ERIM",
address = "Ann Arbor",
keywords = "Meteorology, Remote Sensing--Brazil, Satellites, Brazilian
continental shelf, Global change effects, Holocene sedimentation,
Oceanography.",
abstract = "A study of the shaping of the seafloor morphology on the Brazilian
continental shelf probably caused by abrupt climatic changes in
the beginning of the Holocene is being made with the use of
TM-LANDSAT 5 Data. Special emphasis is given on analysis of an
ancient shoreface at 20m depth, correlated with abrupt global
climate change between 8000-10000 B.P., and on mapping of
sedimentary deposits, which were first described by TM-LANDSAT
imagery. The transport of a quatz sand deposit by unidirectional
currents through time will also be described, together with the
description of presentday active sandwave fields at the 20m
isobath. Two images were used (path/row 214/64 and 215/63, sites
at northeast Brazilian coast), corresponding to two dates: 1984
and 1989. Geometric correction, filter application (striping
minimization)and contrast enhancement were automatically
performed. A gray level slicing image classification technique was
conducted to obtain the preliminary bottom composition chart.
Field work included samples collection from the soft bottom and
beachrock reefs, in areas selected by examination of the final
image products. A Geographical Information System was used to
insert bathymetric and geological data into the analysis system.
The GIS products were registered with the thematic images. The
association of TM data, GIS products and field data helped in the
preliminary sedimentological characterization of the area. Five
bottom types were characterized: fine and coarse sand, coral/algal
bioherms, beachrock reefs and foliaceous algal fields. A
comparison between '84 and '89 images permit us to analyze the
migration pattern of the sand waves, along a five-year period.",
conference-location = "Rio de Janeiro, BR",
conference-year = "27-31 May 1991",
issn = "02755505",
label = "6306",
language = "en",
organisation = "ERIM",
targetfile = "INPE 6804.pdf",
urlaccessdate = "20 abr. 2024"
}