摘要:

Concepts of cyclicity in geology have involved many famous protagonists in the history of Earth sciences. Early in this century, sophisticated theories of terrestrial rhythms had been formulated by such pioneers as T. C.Chamberlin[1909], R. T. ,Chamberlin[1914], Barrell [1917],Stille[1924],Joly[1925, 1930],Holmes[1926],Lull[1929],Schuchert[1932],Grabau[1940], and Umbgrove [1939a,b,1947] (see the review byWilliams[1981]). The physical chemistS. Arrhenius[1908] had also formulated a general hypothesis for cosmological origins of terrestrial phenomena.Khain[1964] later proposed resonances between terrestrial and cosmological rhythms, andMcCrea[1975] andWilliams[1975] summarized evidence of galactic correlations with glaciation.

ISSN:0002-8606    

DOI:10.1029/EO068i050p01651

年代:1987

数据来源: WILEY

摘要:

The sine circle map illustrates periodic patterns discussed in the main article (“The Periodic Structure of the Natural Record, and Nonlinear Dynamics”). These patterns are generated by a recursion algorithm that describes the iterations (ticking) of a nonlinear clock (for example, a clock driven by a nonlinear pendulum). The increments of arc swept out by a clock hand or pointer per unit time (per tick) in such a device, as shown schematically in Figure 1, are not linearly proportional to time; that is, they do not fall at equally spaced tick marks around the clock face. The circle map has served as a model for many complex systems of coupled oscillation in the literature; these systems include experimental studies of the damped driven pendulum, charge density waves in semiconductors, Josephson junctions (coupled superconductors), and Rayleigh‐Bénard convection “for example, Jensen et al., 198

ISSN:0002-8606    

DOI:10.1029/EO068i050p01656

年代:1987

数据来源: WILEY

摘要:

A new international research project will focus on the Cretaceous Period and its sedimentary rocks as a detailed record of global chemical and physical processes. The initiative has been proposed by a committee of the Global Sedimentary Geology Program (GSGP), which the International Union of Geological Sciences (IUGS) adopted in February 1987.Impetus for the new program, called Cretaceous Resources, Events, and Rhythms (CRER), grew out of a recognition of the unique climatic history of the Cretaceous Period (65–135 m.y. B.P.), a time when several marine trangressions left marine sediments covering much of the planet. The relatively complete stratigraphy of the period in many parts of the world offers the opportunity to examine 70 million years of climate change on a global scal

ISSN:0002-8606    

DOI:10.1029/EO068i050p01666-01

年代:1987

数据来源: WILEY

摘要:

Exhibits by manufacturers of instrumentation and equipment, book publishers, and programs of government agencies, along with other displays, will be located in the French Market Exhibit Hall. The exhibits will be open from Tuesday through Thursday from 8:30 A.M. to 4:3 0 P.M. Watch for further details to be published in a future issue ofEos.

ISSN:0002-8606    

DOI:10.1029/EO068i050p01674

年代:1987

数据来源: WILEY

ISSN:0002-8606    

DOI:10.1029/EO068i050p01677

年代:1987

数据来源: WILEY