11000 BCFirst foragers?
6000 BC-800 BCHunter-gatherers
490Basketmaker farming begins
500Turquoise beads and pendants appear; offerings in great kivas (sites 29SJ423, Shabik' eshchee Village)
600-800La Plata Black-on-White ceramic
700Population of Chaco Canyon between 100-200 people
800-900Builders use piñon, juniper, and cottonwood trees that grew close by
850-925Large construction projects. (Plog)
875-1040Red Mesa Black-on-White ceramics
900-1150Large buildings, mounds, roadways, great kivas, and tri-walled structures are built throughout the
San Juan Basin.
900-1125Construction of Penasco Blanco
900Emergence of the Chaco Anasazi
900Chetro Ketl pueblo begun
900-1025Chaco Wash in erosional cycle and cut a paleo-channel.
925-1130Stable environmental conditions favorable to dry farming throughout the
Colorado Plateau. Human populations also stable.
950Keet Seel, second largest cliff dwelling. is inhabited
950Nonlocal
ponderosa is the dominant beam timber;
spruce and
fir increase
960-1020Unpredictable rainfall. Little building at
Pueblo Bonito 1000Chaco phenomenon.
1000-1075Great House construction, and roads expanded (Plog). The first usage of chocolate further than central Mexico was first used in ceramic cylinders for rituals.
1000-1140Escavada Black-on-White ceramics
1025-1090Depositional period during which time the paleo-channel was filling. There is some historical, anecdotal evidence that the inhabitants of Chaco Canyon may have constructed a dam at the west end of the canyon.
1030Chacoans seek trees at higher altitudes
1040Increased rainfall
1040-1050Building resumes at Old Bonito.
Pueblo Bonito construction stage II
1050-1070Pueblo Bonito becomes more complex. Pueblo Bonito construction stage III
1050Imports of copper bells,
Macaws, and shells (origin unknown)
1054~July 4 - Cliff painting near Penasco Blanco consisting of three symbols: a large star, a crescent moon, and a handprint, may portray the sighting of
SN 1054, the Crab Nebula
supernova.
1064, 1066Sunset Crater volcanic eruptions; volcanic debris blankets Jemez Mountains and Bandelier area.
1080-1100Great North Road construction.
1080Salmon Ruin established.
1080Construction of
Pueblo Alto begins.
1090Drought
1075-1123Pueblo Bonito constructed at Chaco.
?Five astronomical observatories are built
1100Peak of Chaco culture.
1100-1104Tree felling at Pueblo del Arroyo
1106-1125Aztec Ruins built.
1130Pueblo Bonito is four stories tall and contains 800 rooms
1130-1180Fifty-year drought in the Southwest. Rain and snow cease to fall. Alluvial groundwater declines, floodplain erosion occurs. Dry-farming zone reduced, crop production potential decreased. Severe arroyo cutting and depression of alluvial groundwater. Severe environmental stress.
1140–1150Collapse of the Ancestral Puebloan culture at Chaco Canyon.
1150Great Houses empty
1180Sunset Crater erupts for the second time.
1539Marcos de Niza erroneously describes the pueblo of Háwikuh as the Seven Cities of Gold.
1680-1692The
Pueblo Revolt of the Pueblo people against Spanish colonists in the New Spain province.
1774Don
Bernardo de Miera y Pacheco identifies the Chaco Canyon area as "Chaca" on a map. The term, a Spanish translation of a Navajo word, is thought to be the origin for "Chacra Mesa" and "Chaco".
1844Josiah Gregg refers to the Chaco pueblos in his book
Commerce of the Prairies, making its first appearance in popular culture.
1849Lt.
James H. Simpson leads the Washington Expedition, a military reconnaissance team which surveys Navajo lands and records cultural sites in Chaco Canyon. Illustrations created by the Kern brothers are included in a government report.
1877Artist and photographer
William Henry Jackson participates in the Hayden Survey of the Western United States, producing maps of Chaco Canyon, but no photographs due to technical problems.
1888Richard Wetherill and Charlie Mason find the
Cliff Palace, Spruce Tree House and Square Tower House.Chaco Canyon is surveyed and photographed by Victor and
Cosmos Mindeleff of the
Bureau of American Ethnology1896Richard Wetherill begins excavating Chaco Canyon
1896-1899George H. Pepper from the
American Museum of Natural History leads the
Hyde Exploring Expedition in excavating Pueblo Bonito
1901General Land Office special agent S. J. Holsinger recommends creating a national park to preserve archaeological sites in Chaco Canyon
1907Chaco Canyon National Monument is established.
1928-1929American astronomer and University of Arizona professor A. E. Douglass participates in a National Geographic Society research project exploring Chaco Canyon. Using his newly invented technique of
dendrochronology, Douglass dates Chetro Ketl and dozens of Chacoan sitesExpedition under Neil Merton Judd to collect dendrochronological specimens to date habitation of Chaco Canyon
1937A
Civilian Conservation Corps of Navajo stonemasons repairs Chacoan buildings in Chaco Canyon. A previous group built soil conservation devices, planted trees, and improved roads and trails.
1941Heavy rains cause Threatening Rock to fall, destroying ~60 rooms at Pueblo Bonito.
1960Floors excavated at Una Vida
1971-1982The Chaco Project, conducted by the
National Park Service and the
University of New Mexico, surveys and excavates Chaco Canyon
1976-1978Fourteen rooms at Pueblo Alto excavated by the Chaco Project
1980Chaco Canyon National Monument is renamed Chaco Culture National Historical Park with 13,000 acres (53 km²) added. The Chaco Culture Archaeological Protection Site program is created to protect Chacoan sites.
1982NASA's Thermal Infrared Multispectral Scanner (TIMS) detects over 200 miles of a prehistoric (AD 900 or 1000) road system in Chaco Canyon, as well as walls, buildings, and agricultural fields.
1983Dean and Warren estimate 200,000 trees were used to build great houses.
1987Chaco Culture National Historical Park is designated a UNESCO World Heritage Site.
2001Two-thirds of large roof timbers traced to Chuska Mountains and one-third to San Mateo Mountains.
