Late Quaternary environments and events on the California Channel Islands
Johnson DL, Coleman D, Glassow MA, Greenwood R, Koeppen H, Walker PL. 1980. Late Quaternary environments and events on the California Channel Islands. Bulletin of the Ecological Society of America. 61(2; Program Issue):106-107
Evidence from alluvial stratigraphic sections on Santa Cruz, Santa Rosa and San Miguel Islands, and at Vandenberg on the California mainland illuminate new aspects of the late Pleistocene-Holocene environment of the coastal zone. The numerous oxidized and charcoal-associated fire areas of Santa Rosa Island, plus recently found equivalents on the other two islands and at Vandenberg, together with a refined radiocarbon chronology indicate that all three islands and the adjacent mainland experienced recurrent episodes of vegetation burning during at least the interval 40,000 to 10,000 radiocarbon years ago. Plant macrofossils and woody charcoal indicate that at least one coniferous element, Cupressus goveniana and probably Pinus radiata, Pseudotsuga and other conifers were affected by the burns, and comprised an important part of the terminal Pleistocene vegetation at least until about 10,800 years ago. Based on this and other evidence, the climate is inferred to have been a moist Mediterranean type, with more wintertime precipitation than at present. Stream channel alluviational episodes alternating with stable soil-forming periods characterized the island stream valleys during the late Pleistocene, and all of the Holocene until the last 1000 years when widespread valley entrenchment and terrace formation occurred.
- Type
- Journal Article
- Authors
- Johnson, D; Coleman, D; Glassow, Michael; Greenwood, R; Koeppen, H; Walker, Phillip
- Units
- CHIS
- Keywords
- CA, CA, Channel Islands National Park, Channel Islands National Park, Fossils, Paleontology, prehistoric plants, Quaternary, Santa Cruz Island, Santa Rosa Island, Stratigraphy