Accession Number:

AD0412368

Title:

Recent Carbonate Sedimentation on Alacran Beef, Yucatan, Mexico.

Descriptive Note:

Corporate Author:

NATIONAL ACADEMY OF SCIENCES-NATIONAL RESEARCH COUNCIL WASHINGTON DC

Personal Author(s):

• Hoskin, Charles Morris

Report Date:

1963-01-01

Pagination or Media Count:

160.0

Abstract:

Hard parts from marine organisms composed or aragonite and calcite, and a trace of siliceous particles from Recent surface sediments on Alacran Reef, a living coral continental shelf atoll in the Gulf of Mexico. These surface sediments are sands and silts which contain minor amounts of gravel and clay-size particles. Within the three major environments of the reef, the windward reef, the leeward reef, and the lagoon, the proportion of each size grade in the sediments is a reflection of the depositional environment coarse sediments accumulate in shallow, wave-washed areas, and fine sediments in deeper water. These three major environments have been subdivided into 19 biotopes, most of which are recognized by criteria of grain size and grain-type composition. Nearly all sub merged sediments are poorly sorted, and most are coarse-skewed andkurtic. The averaged sand fraction of Alacran Reef sediment is com posed of 35 Halimeda, 29 coral, 8 coralline algae, 8 mollusks, 6 foraminifers, 1 miscel laneous skeletal grains, 9 fecal pellets, and 4 aggregates, by volume. Coral grains are most abundant in sediment on the tops of lagoon pin nacle reefs. Author

Descriptors:

• *SEDIMENTATION
• *CARBONATE MINERALS
• MARINE GEOLOGY
• OCEANOGRAPHY
• CORAL REEFS
• PARTICLE SIZE
• STATISTICAL ANALYSIS
• GRAVEL
• SAND
• SILT
• CLAY
• ECOLOGY
• PETROLOGY

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE