Field Seasons: 1995-97

Methodology

A general record for each site was prepared which included site description, location, general environmental data, brief descriptions of artifact and feature types, and a sketch map. Petroglyphs were then individually numbered using removable masking tape. A petroglyph record was filled out, a scale drawing made, and photographs in both black and white and color were taken of each petroglyph. A videotape of one site, El Corozal Viejo (N-RIO-3) was produced.

Lighting conditions were often less than ideal for photography. A portable reflector was used extensively to direct sunlight at an oblique angle onto the petroglyph surface. Often this produced shadows that brought out fine details, particularly in badly eroded petroglyphs, enabling the sketcher to see details that might have been missed.

As one might expect, the sketches often brought out detail clearer than the photographs. Yet, this was not always the case. In fact, the photographs showed greater detail than the sketches in about 10% of the cases, especially after being scanned and the contrast enhanced in Photoshop.

After the fieldwork was completed, site record and petroglyph record information was entered into a computer database. All photographs were scanned, enhanced in Photoshop, and printed out for the report. All sketches and maps were inked. Forms, photographs, and computer discs with data and images were submitted in English and Spanish to the Department of Archaeological Research in Managua for archiving.

Sites Recorded

In the 1995 Field season, four sites were recorded. The greatest concentration of petroglyphs was noted at N-RIO-3, probably recorded by Haberland as Om-38. Located at the top and along the slopes of a ridge, the site contains 82 boulders with petroglyphs, six mortars, two metates and a light scatter of ceramics and chert lithics.

In 1996, a three person crew recorded six additional sites, containing 149 petroglyphs, mostly on land owned by the cooperative at the hacienda.

In 1997, the program was expanded to include volunteers. 20 volunteers participated in recording fifteen additional sites. The most impresive site, N-RIO-19, had an area greater than 180,000 square meters. The site contained 92 petroglyphs, over 30 house mounds, stone statuary fragments, and pottery from at least three different periods of occupation. This material is currently being studied in Managua.