The origin of overpressure in 'old' sedimentary basins: an example from the Cooper Basin, Australia

Overpressure in ‘old’ sedimentary basins that have not undergone rapid, recent sedimentation cannot be easily explained using traditional burial‐driven mechanisms. The last significant burial event in the Cooper Basin, Australia, was the Late Cretaceous deposition of the Winton Formation (98.5–90 Ma). Maximum temperature in the basin was attained during the Late Cretaceous, with cooling beginning prior to 75 Ma. Hence, overpressure related to rapid burial or palaeomaximum temperatures (e.g. hydrocarbon generation) must have developed prior to 75 Ma. Retaining overpressure for 75 Ma in ‘old’ basins such as the Cooper Basin requires extremely low seal permeabilities. An alternative explanation is that overpressure in the Cooper Basin has been generated because of an increase in mean stress associated with an increase in horizontal compressive stress since Late Cretaceous times. Structural observations and contemporary stress data indicate that there has been an increase in mean stress of approximately 50 MPa between Late Cretaceous times to that presently measured at 3780 m. The largest measured overpressure in the Cooper Basin is 14.5 MPa at 3780 m in the Kirby 1 well. Hence, disequilibrium compaction driven by increasing mean stress can explain the magnitude of the observed overpressure in the Cooper Basin. Increases in mean stress (tectonic loading) may be a feasible mechanism for overpressure generation in other ‘old’ basins that have undergone a recent increase in horizontal stress (e.g. Anadarko Basin).     

Folk-Tales of the Aborigines of New South Wales

THE WITCH-CULT IN WESTERN EUROPE. A STUDY IN ANTHROPOLOGY. MARGARET ALICE MURRAY. Oxford: at the Clarendon Press. 1921. Pp. 303. Price 16s. Reviewed by W. R. Halliday.

THE SEMA NAGAS. By J. H. HUTTON, C.I. E., M.A., I.C.S. Published by direction of the Assam Administration. London : Macmillan &; Co. 1921. Price 40s. net. Reviewed by A. C. Haddon.

ANCIENT TALES FROM MANY LANDS : A COLLECTION OF FOLK STORIES. By R. M. FLEMING. With an Introduction by H. J. FLEURE, D.Sc. London: Benn Bros. 1922. Price 10s. 6d. Reviewed by A. Hingston Quiggin.

ASPECTS OF ANCIENT INDIAN POLITY. By NARENDRA NATH LAW, M.A., B.L. ; with a Foreword by ARTHUR BERRIEDALE KEITH, D.C.L., D.Litt. Oxford University Press. London: Milford. Reviewed by H. A. Rose.     

A Note on Medieval Peasant Demography

Abstract

The deed and mortgage registries of the late nineteenth and early twentieth centuries provide a revealing glimpse into the property and power relations of a community. Who owned what? Who was in a position to broker land deals or liens against property? Who accumulated land, and from whom did they acquire it? Consequently, property records are essential elements for understanding the spatial and relational aspects of property holding, especially in rural areas where other sources, such as city directories or fire insurance maps, are not available. Drawing upon her research of African American landowners in Georgia, the author discusses the basics of deeds and mortgages. She describes likely findings in land records and defines common terms and practices. She argucs that the practice of identifying the race of a grantor or grantee, using (col) or less frequently C. P. to denote skin color, varied over time and by locality. Reasons for this practice are discussed and some interpretive rules are offered that may help identify the deeds and mortgages of African Americans when skin color is not noted.     

Death in the sun: the bioarchaeology of an early post-medieval hospital in Gibraltar

SUMMARY: In 2014, during construction work at the ex-Civil Hospital in Gibraltar, excavations led by the Gibraltar Museum revealed a major, previously unknown burial ground containing more than 200 skeletons. We present the historical, archaeological and radiometric dating evidence from the site alongside the results of initial osteological analyses. The data indicate that the burials pertain to an earlier 16th-century Spanish hospice, and therefore stand to offer new insights into the functioning of this early modern hospital and the health and movements of people at a time of incipient globalization.     

RECENT POPULATION TRENDS IN THE USSR

Pending the publication of new Soviet population data based on the 1979 census, to be hald next January, the author reviews population trends in the 1970's. After a steady decline through much of the Soviet period, birth rates and death rates have stabilized for the country as a whole, although marked regional differences continue. An unexplained rise in infant mortality and an apparent reduction of life expectancy have led to the suppression of data in these areas. No ready explanation is found for a recent increase in female fertility and age-specific death rates. Abnormalities in the age-sex structure, resulting from past population catastrophes, continue to persist and indicate future labor shortages. Geographical differences in population growth rates, resulting from differential rates of natural increase and migration, are analyzed. Urbanization, a typical phenomenon of the Soviet period, continues apace, with the biggest increases in large cities despite a policy designed to discourage big-city growth. A crucial question is the optimal disposition of the growing labor pool in the Central Asian region-whether to foster local employment or encourage migration from Central Asia to labor deficit areas elsewhere in the Soviet Union.     

MAN-INDUCED CHANGES IN OVERALL RUNOFF IN THE ARAL SEA BASIN

The article examines the prospects of using runoff characteristics and changes in runoff composition as a basis for predicting environmental modification. The technique is employed to assess changes in the circulation of matter that are taking place in the drainage basin of the Aral Sea as a result of the intensification of irrigation. Overall runoff, including its liquid, solid (suspended sediment) and chemical phases, is analyzed in connection with a shift in the deposition of material from the Aral Sea to the irrigated plains.     

PANEL ON THE SOVIET UNION IN THE YEAR 2000

A panel of geographers debates possible future developments in the Soviet Union in regional and environmental policy, water resource management, agriculture, industry, energy, population, urban growth and planning, transportation, and foreign trade. The present emphasis on modernization of existing plant capacity in cities of the western, more heavily settled regions of the USSR seems destined to continue, although it will be constrained by a growing shortage of industrial labor, declining terms of trade and resource oversupply in increasingly competitive export markets, and the continued resistance of Central Asian populations to urbanization and industrial employment.     

Domains and the Intercultural: Understanding Aboriginal and Missionary Engagement at the Mornington Island Mission,Gulf of Carpentaria,Australia from 1914 to 1942

The Mornington Island Mission in the Gulf of Carpentaria, Australia, was a site of historical engagement between Aboriginal people and missionaries. In this paper, we apply the theoretical concepts of “domains” and the “intercultural” to the investigation of this engagement between 1914 and 1942, when the mission was overseen by the Reverend Robert Wilson. Through the examination of the removal of Aboriginal children, the establishment of a mission compound and Aboriginal camp and the inclusion of Aboriginal adults into the mission compound through production and economy, we show how mutually constituted domains operated. At the same time, the interaction between Aboriginal adults and children with missionaries within these domains was increasingly intercultural in nature. Thus, both “domains” and the “intercultural” are shown to have relevance to the historical case study.