(a.) Ancient; pertaining to the earliest period in geological history.
(n.) The earliest period in geological period, extending up to the Lower Silurian. It includes an Azoic age, previous to the appearance of life, and an Eozoic age, including the earliest forms of life.
Example Sentences:
(1) We formulate the following hypothesis: Life's origin may have occurred during the lower Archaean at a time when the environmental temperature was higher than it is at present.
(2) Hence, the occurrence of sulfate evaporites in Archaean sediments does not necessarily provide testimony of oxidation weathering on the ancient continents and, consequently, of the existence of an atmospheric oxygen reservoir.
(3) Incipient minor differentiation of the isotope pattersn notably of Archaean sulfates may be accounted for by photosynthetic sulfur bacteria rather than by sulfate reducers.
(4) (2) Isotopic evidence of dissimilatory sulfate reduction is first observed in the upper Archaean of the Aldan Shield, Siberia (approximately 3.0 x 10(9) yr) and in the Michipicoten and Woman River banded iron formations of Canada (2.75 x 10(9) yr).
(5) The presently available sedimentary sulfur isotope record for the Precambrian seems to allow the following conclusions: (1) In the Early Archaean, sedimentary delta 34S patterns attributable to bacteriogenic sulfate reduction are generally absent.
(6) (4) With the bulk of sulfate in the Archaean oceans probably produced by photosynthetic sulfur bacteria, the accumulation of SO4(2-) in the ancient seas must have preceded the buildup of appreciable steady state levels of free oxygen.
Laurentian
Definition:
(a.) Pertaining to, or near, the St. Lawrence River; as, the Laurentian hills.
Example Sentences:
(1) Police said Bain, 62, was from near Mont Tremblant, a small town in the Laurentian mountains about 80 miles north-west of Montreal.
(2) 142 second year university students from both Memorial University of Newfoundland (n = 81) and Laurentian University (n = 61) wrote their own signatures as they imagined the following people would do: (a) faculty member (high status) with high self-esteem, (b) faculty member (high status) with low self-esteem, (c) student (low status) with high self-esteem, and (d) student (low status) with low self-esteem.
(3) La Mauricie , Quebec Facebook Twitter Pinterest Breathtaking Laurentian forests of evergreens and hardwoods and 150 crystal-clear lakes make this the quintessential Canadian park experience.
(4) In response to this problem a longitudinal investigation, the Laurentian Study of Biomechanical Development, was launched and in this paper the effects of growth on selected segmental size and inertial parameters are reported for boys between the ages of 4 and 15 yr.
(5) Studies of radioactivity in the Laurentian Great Lakes are reviewed to evaluate the impact of radionuclide dissemination on the world's foremost freshwater aquatic ecosystem.
(6) For 25 secretaries employed at Laurentian University, scores on the MMPI Depression Scale, State-Trait Anxiety Questionnaire, Self-esteem Inventory, Jenkins Activity Survey, and Occupational Stress Questionnaires showed no significant change in behavior associated with occupational stress.
(7) Local media in Montreal identified Bain as the owner of a fishing camp on the shores of Lake Wade in La Conception , near Mont Tremblant in the Laurentian mountains.
(8) Epidemiological criteria were used to examine the influence of environmental contamination on reproductive success of lake trout (Salvelinus namaycush) in the Laurentian Great Lakes.
(9) Montreal police identified the gunman as Richard Henry Bain, 62, from Mont Tremblant, a small town in the Laurentian mountains about 80 miles north-west of Montreal.