The Geomorphological Settings of the Amazon Muddy Coastal Zone: an overview from remote sensing and field ancillary data Pedro Walfir M. Souza Filho Universidade Federal do Pará, Centro de Geociências Centro de Geociências Laboratório de Análise de Imagens do Trópico Úmido

Geologic approach Tectonic, physiographic, geomorphologic, sedimentologic, climatic and oceanographic information from the Amazon coastal zone were reviewed focusing on the factors leading to recognize different geomorphological settings of the Amazon coastal zone

Physiographic aspects Low relief Wide coastal plain and continental shelf High drainage density © 2000 USGS

The control of structural framework on coastal geomorphological setting Morphostructural settings: -Guyana coast -Amapá coast -Marajó island - Pará/ Maranhão coast Gorini & Brian, 1976

Sedimentary environments: coastal zone and continental shelf

Geomorphological Settings of the Amazon Muddy Coastal Zone Souza Filho & Prost, 2002

Sector I: Guyana Coast - Muddy Capes Geomorphological Investigation from ERS-1 Erosional Interbank and Depositional Mud Bank Zone in French Guiana KourouCSG Salut Islands N ERS-1 image © European Space Agency, 1992 Avicennia sp. Mangrove Mud Banks Erosional Interbank Depositional Mud Bank

Sector I: Amapá Coast Muddy Capes and Fringed Mangroves Cunani Estuarine Mouth - Amapá ERS-1 image © ESA, March Mud bank Beach ridge Marsh Beach ridge Mud bank N Orange and Cassiporé capes - Amapá JERS-1 image © NASDA, Oct

Sector II: Lake region and Marajó Island Wet grassland Franco Island, Gurijuba Channel- Amapá ERS-1 image © ESA, 1992 Emerged mud banks Submerged mud banks Grassland Emerged mud bank Grassland Gurijuba channel Franco Island N Lakes region - Amapá JERS-1 image © NASDA, Oct

Sector III: Marajó Island Wet grassland Wet-grass land - Marajó JERS-1 image © NASDA, Oct

Sector IV: Pará - Maranhão Coast Macrotidal Mangrove N ERS-1 image © ESA, 1992 Northeastern Pará State Coastal Plateau Mangroves Savannah Dune-Beach ridge Ebb-tidal delta

Muddy Coast: processes in different spatial scale

Mangrove coast km2 Souza Filho & Lara, in press

Geomorfological Investigation Based on RADARSAT and Landsat TM Integrated Product Bragança Mangrove Coast - Pará Coastal Features a = intertidal mangroves b = supratidal mangrove c = deforested mangrove d = regenerated mangrove e = inner salt marsh f = outer salt marsh g = chenier sand ridge h = barrier-dune beach ridge, i = ebb-tidal delta j = tidal sandflat k = submerse sandy bank l = tidal estuarine channel 82% muddy environments

Geomorfological Investigation...

Geomorphological Map from SPC-SAR Integrated Product Different muddy coastal sedimentary environments

Muddy Coast: processes in different time scale

Stratigraphic evolution of the Bragança Coastal Plain What happened 2,100 years ago? Sandy coast  Muddy coast

Medium-Term Shoreline Changes from Airborne (GEMS, 1972) and Spaceborne (RADARSAT, 1998) SAR 10 km A B C RADARSAT image: 1998 GEMS 1000 vector: 1972 Shoreline change: A = ; B = ; C =  28m

Medium-Term Shoreline Changes... Erosive shoreline Progradational shoreline RADARSAT image © Canadian Space Agency, 1998

Shoreline change evaluation ( ) Which are the main processes that control erosion/accretion along the time?

Shallow Water Morphology and Coastal Processes from RADARSAT-1. RADARSAT image © Canadian Space Agency, 1998

Summary of Coastal Studies on Amazon Region ú Distinct remote sensing systems with different configurations have provided high quality data for muddy coastal features identification in wet tropical environments. ú The effective applicability of the remote sensing technology depends on the understanding of radar and optical RS fundamentals, digital image processing, field investigations and the knowledge about the discipline vs. application involved. ú SAR data will provide to geoscientist a powerful terrain visualization of the coastal geomorphological units, which can not be acquired from field observations alone. ú This lecture has shown the importance of using remote sensing as a fundamental tool for mapping and monitoring purposes in moist tropical coastal environments of the Amazon region. ú Geomorphologic, stratigraphic and oceanographic processes must be understood on different time and spatial scale. How we can do this?

The great objective of many generations is: Try to understand what is going on Amazon muddy coast?