Child care demand and labor supply of young mothers over time
The paper uses panel data from the National Longitudinal Survey of Youth (United States) to analyze jointly fertility, employment, and child care decisions of young women over time.
Four holocene alluvial fills are present. Fill IV, the oldest and thickest, was deposited between 10 200 and 4 800 C 14 yr B.P.| Fill III has an age of about 3 000 C 14 yr B.P.| Fill II is younger than 2 100 and older than 900 C 14 yr B.P.| and Fill
I is younger than 900 C 14 yr B.P. Regional contemporaneity of valley alluviation in the eastcentral Great Plains suggests that climate has controlled long-term sediment storage in the South Loup River valley.
throughout the valley. Glacier cover was reduced to about half that of the last glacial maximum by at least 9 700 yr B.P. and to less than a tenth by at least 6 450 yr B.P. No unambiguous Younger Dryas moraines are present.
and McLean must also be considered younger than previously thought. The persistence of the Laurentide Ice Sheet margin on the central Labrador coast until 7 600 yr ago probably restricted the northward movement of early prehistoric people into northern
of ostracods, molluscs, and the dated moss all support a young deglacial scenario. The ice margin appears to have retreated into the southern Lake Agassiz basin after 12 000 yr B.P. and north of the Rossendale site by 11 000 B.P. About 10 000 yr B.P., following
of Coleogyne ramosissima (blackbrush), macrofossils of this shrub are only present in samples younger than 270 yr B.P. In order to measure changes more subtle than presence vs absence, macrofossil concentrations were quantified, and principal components
Near Summer Lake in southern Oregon, 54 tephra beds of late Quaternary age are exposed in pluvial lake sediments of lake Chewaucan. Seven of the tephra beds near the top can be correlated with tephra deposits younger than 117,000 yr at Mount St
an episode of mild climate in the middle Holocene prior to at least two intervals of glacier expansion: an older episode between 5100 and 3400 yr B.P., and a younger episode within the last 1000 yr.
and younger surfaces are developed mostly on Mesozoic and Cenozoic rocks, but more widely within the limits of the Andes zone. Tectonic uplift amplitudes are defined by measurements of planation surfaces distortions, shown at the applied map with isobases
An offlapping sequence of glacial and glacial-lacustrine sediments overlying bedrock is recognized in west-central Lake Superior that is progressively younger to the northeast. Four facies are recognized on the basis of geomorphologic and acoustic