{"title":"in the Persian Gulf","authors":"Mr J W Jackson","doi":"10.2307/j.ctt1r33pxt.4","DOIUrl":"https://doi.org/10.2307/j.ctt1r33pxt.4","url":null,"abstract":"Some months ago I received from Dr. J. Cosmo Melvill a small box containing brachiopods from the Persian Gulf. These had been obtained by Mr. F. W. Townsend in the course of his dredgings for Mollusca in that region. The locality on the box containing the specimens is Dabai, which lies within the Persian Gulf on the N.W. coast of Oman. Its exact position is on the west side of the peninsula of Ruus El Jibal, on what is known as the Pirate Coast. Unfortunately, no particulars as to depth etc. accompanied the specimens. With the exception of the Mollusca and some Madreporarian corals very little appears to be known of the fauna of the Persian Gulf. The Mollusca have been ably dealt with in a series of papers by Messrs. Melvill and Standen*, and the corals were described in 1911 in a paper by Miss Ruth Harrison \"f, to which Professor S. J. Hickson added some further notes J. The discovery of Brachiopoda in the Persian Gulf is of very great interest, not only from the fact that these specimens are the first of the class to be recorded from this region — i. e., the N.W. corner of the Indian Ocean (including the Persian Gulf, Gulf of Oman, and Arabian Sea), — but more especially from the important bearing of these specimens on the subject of the relation of the fauna of the Persian Gulf to that of the Mediterranean Sea and Atlantic Ocean. Four specimens only were present in the box, one of which is a Terebratulina, the other three belonging to the genus Muhlfeldtia. All are dead empty shells, and a small quantity of greyish marl was present in the interior of one or two. Unfortunately , in the case of the Terebratulina, the brachidium, or loop, is broken, but the shell is otherwise quite perfect, both valves being present. In form and size it is very like a specimen of Terebratulina caput-serpentis figured by Fischer and Oehlert from the ' Talisman ' Expedition in the Lusitanian Subregion §. It has the same general outline and is cut off","PeriodicalId":55106,"journal":{"name":"Geoscience Canada","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68720516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Geoscience CanadaPub Date : 2022-12-17DOI: 10.12789/geocanj.2022.49.192
Tracy J. Webb
{"title":"The Last Billion Years: A Geological History of the Maritime Provinces of Canada","authors":"Tracy J. Webb","doi":"10.12789/geocanj.2022.49.192","DOIUrl":"https://doi.org/10.12789/geocanj.2022.49.192","url":null,"abstract":"","PeriodicalId":55106,"journal":{"name":"Geoscience Canada","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46631019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Geoscience CanadaPub Date : 2022-12-17DOI: 10.12789/geocanj.2022.49.191
J. Murphy, W. J. Collins, D. Archibald
{"title":"Logan Medallist 7. Appinite Complexes, Granitoid Batholiths and Crustal Growth: A Conceptual Model","authors":"J. Murphy, W. J. Collins, D. Archibald","doi":"10.12789/geocanj.2022.49.191","DOIUrl":"https://doi.org/10.12789/geocanj.2022.49.191","url":null,"abstract":"Appinite bodies are a suite of plutonic rocks, ranging from ultramafic to felsic in composition, that are characterized by idiomorphic hornblende as the dominant mafic mineral in all lithologies and by spectacularly diverse textures, including planar and linear magmatic fabrics, mafic pegmatites and widespread evidence of mingling between coeval mafic and felsic compositions. These features suggest crystallization from anomalously water-rich magma which, according to limited isotopic studies, has both mantle and meteoric components. Appinite bodies typically occur as small (~2 km diameter) complexes emplaced along the periphery of granitoid plutons and commonly adjacent to major deep crustal faults, which they preferentially exploit during their ascent. Several studies emphasize the relationship between intrusion of appinite, granitoid plutonism and termination of subduction. However, recent geochronological data suggest a more long-lived genetic relationship between appinite and granitoid magma generation and subduction.Appinite may represent aliquots of hydrous basaltic magma derived from variably fractionated mafic underplates that were originally emplaced during protracted subduction adjacent to the Moho, triggering generation of voluminous granitoid magma by partial melting in the overlying MASH zone. Hydrous mafic magma from this underplate may have ascended, accumulated, and differentiated at mid-to-upper crustal levels (ca. 3–6 kbar, 15 km depth) and crystallized under water-saturated conditions. The granitoid magma was emplaced in pulses when transient stresses activated favourably oriented structures which became conduits for magma transport. The ascent of late mafic magma, however, is impeded by the rheological barriers created by the structurally overlying granitoid magma bodies. Magma that forms appinite complexes evaded those rheological barriers because it preferentially exploited the deep crustal faults that bounded the plutonic system. In this scenario, appinite complexes may be a direct connection to the mafic underplate and so its most mafic components may provide insights into processes that generate granitoid batholiths and, more generally, into crustal growth in arc systems.","PeriodicalId":55106,"journal":{"name":"Geoscience Canada","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41402126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Geoscience CanadaPub Date : 2022-07-19DOI: 10.12789/geocanj.2022.49.190
P. Dimmell
{"title":"MINING COUNTRY — A History of Canada’s Mines and Miners","authors":"P. Dimmell","doi":"10.12789/geocanj.2022.49.190","DOIUrl":"https://doi.org/10.12789/geocanj.2022.49.190","url":null,"abstract":"","PeriodicalId":55106,"journal":{"name":"Geoscience Canada","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41838170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Geoscience CanadaPub Date : 2022-07-19DOI: 10.12789/geocanj.2022.49.187
De Wet van Rooyen
{"title":"Looking Back to Move Forward: Why Scientific Societies Should Contribute to Making our Science an Equitable, Safe, and Inclusive Space","authors":"De Wet van Rooyen","doi":"10.12789/geocanj.2022.49.187","DOIUrl":"https://doi.org/10.12789/geocanj.2022.49.187","url":null,"abstract":"","PeriodicalId":55106,"journal":{"name":"Geoscience Canada","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45271241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Geoscience CanadaPub Date : 2022-07-19DOI: 10.12789/geocanj.2022.49.189
A. Miall
{"title":"A Symposium in Honour of Gerard V. Middleton: GeoConvention, Calgary, June 21, 2022","authors":"A. Miall","doi":"10.12789/geocanj.2022.49.189","DOIUrl":"https://doi.org/10.12789/geocanj.2022.49.189","url":null,"abstract":"Gerard Middleton, Emeritus Professor at McMaster University, passed away on 2nd November 2021 at the age of 90. Gerry, as he was happy to be called, was one of the first geologists in Canada to “self-identify” as a sedimentologist, although he started his career as a paleontologist working on Devonian carbonate sediments. He arrived at McMaster University in 1955, and soon switched to sedimentary geochemistry, and then to the study of clastic sedimentary processes, a field that, at that time, could be said to have not even reached the stage of infancy. In the 1960s and 1970s Gerry made fundamental advances in our understanding of sediment transport and the identification, classification and interpretation of hydrodynamic sedimentary structures and sediment gravity flows (a term Gerry coined). Gerry retired in 1996, and a special issue of this journal (v. 24, #1, 1997), under the editorship of then editor Roger Macqueen, was dedicated to his lifetime contributions as researcher, author and editor. Gerard’s career and his substantial contributions to the progress of the geosciences in Canada are also expertly summarized in the obituary Bob Dalrymple and Janok Bhattacharya (2021) published in Geoscience Canada. We now have a certain perspective with which to look back on Gerry’s contributions to the science of sedimentology and assess their significance, and it is fair to say that he was at the centre of several of the most fundamental breakthroughs in our understanding of clastic sedimentary processes. The GeoConvention 2022 symposium was designed to focus on these developments, and the advances that have been made, based on his research, by his former students and associates, and by others who have benefited intellectually from his long-lasting influence. His many other contributions to the life and work of Canadian geoscience are ably summarized by Dalrymple and Bhattacharya (2021). John Southard, of MIT, was invited to present some opening remarks to the symposium from his office, via Zoom. His personal reminiscences of working with Gerry, and the research they initiated in the field of sediment hydraulics helped to put the history and development of the field into perspective, and we enjoyed some of the personal stories of two productive researchers working together to essentially create an entire new field of sedimentology. A truly successful research professor is one who can inspire students, and several of the speakers at this symposium (Dalrymple, Bhattacharya, Plint, Leckie and Arnott) were privileged to have been part of the large body of students who passed through the McMaster “school” of sedimentology in the 1970s, led by Gerry and his colleague, Roger Walker. Dalrymple was supervised by Gerry; Bhattacharya and Leckie by Walker; Plint was a post-doctoral fellow working with Roger Walker, and Arnott an undergraduate. For at least two decades, the 1970s and 1980s, the Middleton-Walker school was arguably one of the top two truly “world c","PeriodicalId":55106,"journal":{"name":"Geoscience Canada","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44176246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}