Lake Titicaca

LAKE TITICACA DRILLING PROJECT

Lake Titicaca in Bolivia and Peru contains one of the most significant climatic archives in South America. It has been identified as one of the primary sites for completion of the Pole-Equator-Pole paleoclimatic transect of the Western Hemisphere. Lake Titicaca is the only large, deep freshwater lake in South America. In 2001, DOSECC cored three sites in Lake Titicaca using the GLAD800. During this project, we collected a total of 593.6 m of core. The deepest hole was 139 m of sediment with a water depth of 232 m.

Lake Titicaca is located at 3810 m in the Andes and is bordered by cordillera that reach over 6000 m to the east and west. Although these mountains support modern alpine glaciers, during prior phases of major glaciation (e.g. the last glacial maximum, or ~21,000 yr BP) the lake was not covered by glaciers and consequently contains a long record of glaciation and climate change in the tropical Andes. Scientists have split and described the drill cores, which come from three sites in the lake, at LacCore (University of Minnesota), the US national repository for lake cores.

Sediment cores were sampled from the three sites at a 20 cm resolution, and in some cases at a higher spatial resolution, for a total of ~1800 samples. Analyses that are currently underway include total organic carbon, total inorganic carbon, detrital grain size, diatom analysis, biogenic silica, stable isotopes of the organic carbon and carbonate, and geochemical characterization of volcanic ashes in the sediment cores. Scientists have obtained ~75 AMS radiocarbon dates from the drill cores and they have pending Ar/Ar analyses of the volcanic ashes to provide an absolute chronology beyond the range of radiocarbon. The sediment records clearly show the last glacial cycle in the Andes, significant lake level variations, and hydrologic changes that reflect the strength of tropical hydrologic cycling in the late Quaternary.

ADDITIONAL INFORMATION ABOUT THE PROJECT

Drilling Project - April 26, 2001 to May 24, 2001

Principal Investigators: Dr. Paul Baker, Duke University; Dr. Geoffrey Seltzer, Syracuse University; and Dr. Sherilyn Fritz, University of Nebraska.

Project Funding Sponsors: National Science Foundation (NSF) and International Continental Drilling Program (ICDP).

Website Links relating to Lake Titicaca Drilling:

ICDP Website
GEOTIMES Article, Dec. 2001
Dr. Paul Baker
ODP Newsletter
Lake Titicaca - Geology, History, Biology
Duke News Service

	Measurements in Meters
Hole ID	Cored (length)	Recovered (length)	% Recovered	Water Depth	Max Hole Depth (from lake surface)	Depth Penetrated
1A	53.03	45.01	85%	142	196.62	54.62
1B	59.13	44.57	75%	142	215.36	73.36
2A	63	58.5	93%	232	293	61
2B	139.26	140.61	101%	232	365.7	133.7
2C	70.13	78.36	112%	232	355.13	66.13
3A	134.41	112.59	84%	40	166.68	126.68
3B	121.88	113.96	94%	40	163.17	123.17