Correlation of Lower Silurian strata from the Michigan Upper Peninsula to Manitoulin Island

1981 ◽  
Vol 18 (5) ◽  
pp. 869-883 ◽  
Author(s):  
Markes E. Johnson

The same approach in using sea-level curves to refine time-rock correlations between widely separated regions also has an important application in resolving the tangle of dual stratigraphic nomenclature that often develops in neighboring regions divided by political boundaries. A good example is the Lower Silurian of the Michigan Upper Peninsula and Manitoulin Island, Ontario. Four peaks in sea-level fluctuation are recorded in both areas by coeval pentamerid communities stratigraphically intermixed with coral–algal and ostracode–vermiform communities indicative of shallower water conditions. Despite many similarities between the rock units containing these fossil communities, most are identified by different formation names on opposite sides of the U.S.–Canadian border. This study details the eastward thinning of strata across the boundary area. The Cordell dolomite of Michigan is extended to Manitoulin Island, but not the underlying Schoolcraft dolomite, due to the pinching out of beds that define its upper and lower contacts. The Fossil Hill Formation of Manitoulin Island is accordingly reduced but retained even though it contains some of the other subformational units represented in the Schoolcraft. Facies relationships between the Michigan Hendricks dolomite and its correlative Mindemoya and St. Edmund Formations argue for their valid maintenance. The relationship between the Byron and Wingfield Formations is less clear. Probably the Dyer Bay Formation should be extended to Michigan in place of the Lime Island dolomite.

1982 ◽  
Vol 19 (5) ◽  
pp. 962-974 ◽  
Author(s):  
Valerie R. Colville ◽  
Markes E. Johnson

Paleobathymetric interpretation of strata from the Bruce Peninsula and Lake Timiskaming District of Ontario shows strong correlations with data from the Michigan Upper Peninsula and Ontario's Manitoulin Island. Three to four cycles of fluctuating sea level occurred during Early Silurian (Llandoverian) time throughout much of the northern Great Lakes area, and involved the highly regular replacement of ostracode–vermiform, coral–algal, and pentamerid communities by one another. Although exposure is more limited than on Manitoulin Island or the Michigan Upper Peninsula, important clues regarding Early Silurian geography are found in strata of the Bruce Peninsula and Lake Timiskaming District. Continued thinning of stratigraphic units and an increased incidence of disconformities from north to south on the Bruce Peninsula suggest the episodic rise of the Algonquin Arch farther to the south and west. Contrary to earlier paleogeographic reconstructions, the patterns of community changeovers preserved in the Silurian outlier of the Lake Timiskaming District indicate a persistent, open connection between the seas of the northern Great Lakes area and the Hudson Bay Lowlands. This interpretation is more in keeping with recent paleontologic work on faunal distributions.


Author(s):  
Lital Levy

A Palestinian-Israeli poet declares a new state whose language, “Homelandic,” is a combination of Arabic and Hebrew. A Jewish-Israeli author imagines a “language plague” that infects young Hebrew speakers with old world accents, and sends the narrator in search of his Arabic heritage. This book brings together such startling visions to offer the first in-depth study of the relationship between Hebrew and Arabic in the literature and culture of Israel/Palestine. More than that, the book presents a captivating portrait of the literary imagination's power to transgress political boundaries and transform ideas about language and belonging. Blending history and literature, the book traces the interwoven life of Arabic and Hebrew in Israel/Palestine from the turn of the twentieth century to the present, exposing the two languages' intimate entanglements in contemporary works of prose, poetry, film, and visual art by both Palestinian and Jewish citizens of Israel. In a context where intense political and social pressures work to identify Jews with Hebrew and Palestinians with Arabic, the book finds writers who have boldly crossed over this divide to create literature in the language of their “other,” as well as writers who bring the two languages into dialogue to rewrite them from within. Exploring such acts of poetic trespass, the book introduces new readings of canonical and lesser-known authors, including Emile Habiby, Hayyim Nahman Bialik, Anton Shammas, Saul Tchernichowsky, Samir Naqqash, Ronit Matalon, Salman Masalha, A. B. Yehoshua, and Almog Behar. By revealing uncommon visions of what it means to write in Arabic and Hebrew, the book will change the way we understand literature and culture in the shadow of the Israeli–Palestinian conflict.


2007 ◽  
Vol 37 (2) ◽  
pp. 338-358 ◽  
Author(s):  
Ichiro Fukumori ◽  
Dimitris Menemenlis ◽  
Tong Lee

Abstract A new basin-wide oscillation of the Mediterranean Sea is identified and analyzed using sea level observations from the Ocean Topography Experiment (TOPEX)/Poseidon satellite altimeter and a numerical ocean circulation model. More than 50% of the large-scale, nontidal, and non-pressure-driven variance of sea level can be attributed to this oscillation, which is nearly uniform in phase and amplitude across the entire basin. The oscillation has periods ranging from 10 days to several years and has a magnitude as large as 10 cm. The model suggests that the fluctuations are driven by winds at the Strait of Gibraltar and its neighboring region, including the Alboran Sea and a part of the Atlantic Ocean immediately to the west of the strait. Winds in this region force a net mass flux through the Strait of Gibraltar to which the Mediterranean Sea adjusts almost uniformly across its entire basin with depth-independent pressure perturbations. The wind-driven response can be explained in part by wind setup; a near-stationary balance is established between the along-strait wind in this forcing region and the sea level difference between the Mediterranean Sea and the Atlantic Ocean. The amplitude of this basin-wide wind-driven sea level fluctuation is inversely proportional to the setup region’s depth but is insensitive to its width including that of Gibraltar Strait. The wind-driven fluctuation is coherent with atmospheric pressure over the basin and contributes to the apparent deviation of the Mediterranean Sea from an inverse barometer response.


Author(s):  
Д.П. Ковалев ◽  
П.Д. Ковалев ◽  
А.С. Борисов

В работе рассмотрены особенности колебаний пришвартованного судна для основных портов Сахалинской области, поскольку качка судна у причала может представлять опасность и приводить к повреждению судна или швартовых линий. По данным натурных измерений морского волнения в портовых бухтах рассчитаны спектры колебаний уровня и определены периоды существующих в них волн для диапазона периодов от 2 с до 30 минут. Произведен расчет периодов собственных колебаний (качки) двух типов судов, преимущественно швартующихся в портах. С учетом полученных результатов выполнено моделирование движения судов при волнении как динамической с системы внешним возбуждающим воздействием на основе дифференциального уравнения второго порядка. Показано влияние коэффициента вязкого демпфирования и жесткости швартовых на реакцию динамической системы без удара о причал и для режима ударного осциллятора. Установлено, что в случае прихода в район порта Корсаков длинноволновой зыби движения судна могут переходить в хаотические. The paper considers the peculiarities of moored vessel oscillations for the main ports of the Sakhalin region, since the pitching of the vessel at the berth can be dangerous and lead to damages of the vessel or mooring lines. Spectra of sea level fluctuations and periods of waves in port bays were calculated using sea level fluctuation measurements obtained in the range from 2 seconds to 30 minutes. Calculations of resonance periods (pitching) of two types of vessels mainly moored in ports were done. Taking into consideration these results the simulation of the vessel movement in waves as a dynamic system with an external excitation was performed on the base of second-order differential equation. The influence of viscous damping coefficient and mooring stiffness on the response of the dynamic system is shown for two cases: for system without impact and for the impact oscillator mode. It is established that in the event of a long-wave swell coming to the Korsakov port area, the vessels movements may become chaotic.


2004 ◽  
Vol 202 ◽  
pp. 401-414 ◽  
Author(s):  
C. X. Li ◽  
V. Ivanov ◽  
D. D. Fan ◽  
V. Korotaev ◽  
S. Y. Yang ◽  
...  

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