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M. Stuiver

Publications and source records attributed to M. Stuiver.

7 recordsLinked to original sources
USGS1995

Radiocarbon evidence for extensive plate-boundary rupture about 300 years ago at the Cascadia subduction zone

The Cascadia subduction zone, a region of converging tectonic plates along the Pacific coast of North America, has a geological history of very large plate-boundary earthquakes1,2, but no such earthquakes have struck this region since Euro-American settlement about 150 years ago. Geophysical estimates of the moment magnitudes (Mw) of the largest such earthquakes range from 8 (ref. 3).to 91/2 (ref. 4). Radiocarbon dating of earthquake-killed vegetation can set upper bounds on earthquake size by constraining the length of plate boundary that ruptured in individual earthquakes. Such dating has shown that the most recent rupture, or series of ruptures, extended at least 55 km along the Washington coast within a period of a few decades about 300 years ago5. Here we report 85 new 14C ages, which suggest that this most recent rupture (or series) extended at least 900 km between southern British Columbia and northern California. By comparing the 14C ages with written records of the past 150 years, we conclude that a single magnitude 9 earthquake, or a series of lesser earthquakes, ruptured most of the length of the Cascadia subduction zone between the late 1600s and early 1800s, and probably in the early 1700s.

California, Oregon, Washington↗
USGS1995

Large arctic temperature change at the Wisconsin-Holocene glacial transition

Analysis of borehole temperature and Greenland Ice Sheet Project II ice-core isotopic composition reveals that the warming from average glacial conditions to the Holocene in central Greenland was large, approximately 15°C. This is at least three times the coincident temperature change in the tropics and mid-latitudes. The coldest periods of the last glacial were probably 21°C colder than at present over the Greenland ice sheet.

Science↗
USGS1991

Radiocarbon test of earthquake magnitude at the Cascadia subduction zone

The Cascadia subduction zone, which extends along the northern Pacific coast of North America, might produce earthquakes of magnitude 8 or 9 ('great' earthquakes) even though it has not done so during the past 200 years of European observation 1–7 . Much of the evidence for past Cascadia earthquakes comes from former meadows and forests that became tidal mudflats owing to abrupt tectonic subsidence in the past 5,000 years 2,3,6,7 . If due to a great earthquake, such subsidence should have extended along more than 100 km of the coast 2 . Here we investigate the extent of coastal subsidence that might have been caused by a single earthquake, through high-precision radiocarbon dating of coastal trees that abruptly subsided into the intertidal zone. The ages leave the great-earthquake hypothesis intact by limiting to a few decades the discordance, if any, in the most recent subsidence of two areas 55 km apart along the Washington coast. This subsidence probably occurred about 300 years ago.

California, Oregon, Washington↗
USGS1988

The radiocarbon budget for Mono Lake: An unsolved mystery

Since 1957 the 14 C/C ratio of the dissolved inorganic carbon in Mono Lake has risen by about 60‰. The magnitude of this increase is about four times larger than that expected from the invasion of bomb-produced 14 C from the atmosphere. We have eliminated the following explanations: (1) measurement error, (2) an unusually high physical exchange rate for non-reactive gases, (3) inorganic enhancement of the CO 2 exchange rate, and (4) biological enhancement of the CO 2 exchange rate. Clandestine disposal of waste radiocarbon remains a dark-horse explanation. In the course of our investigations we have uncovered evidence for at least one episodic input of radiocarbon-free carbon to the lake over the last 1000 years. We speculate that this injection was related to a hydrothermal event resulting from sublacustrine volcanic activity.

Earth and Planetary Science Letters↗
USGS1981

Comparison of uranium-series, radiocarbon, and amino acid data from marine molluscs, Baffin Island, Arctic Canada

Uranium-series and 14 C dates and the extent of amino acid racemization are reported for 24 marine shell samples from three areas of Baffin Island, Arctic Canada. When the radiometric dates are plotted against the ratio of D-alloisoleucene:L-isoleucene in the shells, five broad age groups are recognized. The uranium-series data indicate that 231 Pa is incompletely retained in most fossil shells and that 230 Th is lost from some of the samples. Therefore, their apparent ages are minimum. However, a few dated samples in each group have yielded useful age results, and the minimum ages of the five groups of samples are estimated as 7,000 to 11,000, ≥ 70,000, ≥ 136,000, ≥ 190,000, and > 300,000 yr. Calculated integrated thermal histories based on the epimerization reaction in the mollusc Hiatella arctica Linné give paleotemperature estimates of around −5 °C, compared to the present mean annual air temperature of about −11 °C.

Baffin Island↗
USGS1969

Florida submergence curve revised: Its relation to coastal sedimentation rates

New data substantiate as well as modify the south Florida submergence curve, which indicates that eustatic sea level has risen continuously, although at a generally decreasing rate, during the last 6500 to 7000 sidereal years (5500 standard radiocarbon years) to reach its present position. Accumulation rates of coastal deposits are similar to the rate of sea-level rise, thus supporting the generalization that submergence rates largely determine as well as limit rates of coastal sedimentation in lagoonal and estuarine areas.

Florida↗