Snowball Earth climate dynamics and Cryogenian geology–geobiology

Geological evidence indicates that grounded ice sheets reached sea level at all latitudes during the long‐lived Sturtian (717–659 Ma) and Marinoan (ca 645–635 Ma) glaciations. Combined U-­‐Pb and Re-­‐Os geochronology suggests that the Sturtian glacial onset and both terminations were globally synchronous. Geochemical data imply that atmospheric pCO2 was 102x modern at the Marinoan termination, consistent with Snowball Earth hysteresis. Sturtian glaciation followed the breakup of a tropical supercontinent, and its onset coincided with the equatorial emplacement of a large igneous province. Modeling shows that the small thermal inertia of a globally frozen surface reverses the annual-mean Hadley circulation, resulting in equatorial net sublimation and net deposition elsewhere. Oceanic ice thickens, forming a sea glacier that flows gravitationally toward the equator, sustained by the hydrologic cycle and by basal freeze-on and melting. Tropical ice sheets flow faster as CO2 rises, but lose mass and become sensitive to orbital forcing. Dust accumulation in the equatorial zone engenders supraglacial oligotrophic meltwater ecosystems, favorable for cyanobacteria and many eukaryotes. Meltwater flushing through moulins enables organic burial and submarine deposition of subaerially-­‐erupted volcanic ash. The subglacial ocean is turbulent and well­‐mixed, in response to geothermal heating and conductive heat loss through the ice cover, increasing with latitude. Cap carbonates, unique to Snowball Earth terminations, are products of intense weathering and ocean stratification. Whole-­ocean warming and ice-sheet forebulge collapse allow marine coastal inundations to progress long after ice-sheet disappearance. The evolutionary legacy of Snowball Earth is perceptible in fossils and living organisms

Cœlenterata : [a collection of journal articles chiefly on sponges]

Contents listingScanned from the original held in Rare Books & Special Collections, Barr Smith Library.A collection of articles and reprints of articles, chiefly on sponges, and chiefly relating to Australia, from various journals; but particularly those by Dr. R. von Lendenfeld as published in the Proceedings of the Linnean Society of New South Wales; all collected and bound together by Howchin

Tracts - Geology : [a collection of journal articles on geology]

Contents listingScanned from the original held Rare Books & Special Collections, Barr Smith Library.A collection of articles and reprints of articles on geology, chiefly relating to Australia, issued between 1864 and 1896, and from various journals; as collected and bound together by Professor Ralph Tate and bought by Howchin

Polyzoa tracts : [a collection of journal articles on Polyzoa]

Scanned from the original held in Rare Books & Special Collections, Barr Smith Library.Collective title supplied by cataloguer from former owner’s binding Includes bibliographical reference

Geology : [a collection of his journal articles on geology]

Walter Howchin’s articles on geology, 1879-1934 Collected articles, 1879-1934 Full contents listingA collection of articles and reprints of articles on geology, chiefly relating to Australia, issued between 1848 and 1905, and from various journals; as collected and bound together by Howchin

Native implements, Australia and Tasmania : [a collection of journal articles]

Contents listingScanned from the original held in Rare Books & Special Collections, Barr Smith Library.A collection of articles and reprints of articles on Aboriginal Australian native implements; all collected and bound together by Howchin

Note on the occurrence of casts of Radiolaria in Pre-Cambrian (?) rocks, South Australia

Volume: 21Start Page: 571End Page: 58