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Regional geochemical characterization of groundwaters in a bedrock aquifer in the Ottawa--St. Lawrence Lowlands of eastern Ontario has identified an iodine (I) anomaly, with values regularly exceeding 150 [micro]g/L and a maximum observed concentration of 10 812 [micro]g/L. The spatial distribution, enrichment mechanisms, and sources of I and organic matter were investigated using geochemical and isotopic data. High-I groundwaters (>150 [micro]g/L) are prevalent in Na-Cl-type groundwaters at low bedrock elevations in areas overlain by thick layers of glacial sediments. I is thought to be linked to massive muds in the glacial sediments overlying the aquifer, deposited during the postglacial incursion of the Champlain Sea 12-10 ka BP. Principal component analysis of I and 18 other chemical parameters revealed correlations among I, salinity, and indicators of microbial oxidation of organic matter, suggesting that the intrusion of saline pore waters affected by decomposition of organic matter such as marine phytoplankton in the massive muds is the dominant process controlling I enrichment in groundwater. [.sup.129]I/[.sup.127]I ratios in the pre-modern waters vary between near-marine values of 460 x [10.sup.-14] and 5 x [10.sup.-14], demonstrating that older allochthonous I derived from the surrounding Paleozoic sedimentary terrain also contributed to the I pool in the Champlain Sea basin. [.sup.14]C ages and [delta][.sup.13]C signatures for dissolved organic carbon in groundwater and disseminated organic carbon within the glaciomarine muds highlight an allochthonous source of terrestrial organic carbon predating the Champlain Sea incursion, likely transported via glacial meltwaters in tandem with I to the Champlain Sea basin. La caracterisation geochimique regionale des eaux souterraines dans un aquifere rocheux dans les Basses Terres de l'Outaouais et du Saint-Laurent de l'est de l'Ontario a fait ressortir une anomalie d'iode (I), avec des valeurs excedant regulierement 150 [micro]g/L et une concentration maximum observee de 10 812 [micro]g/L. La repartition spatiale, les mecanismes d'enrichissement et les sources d'I et de matiere organique ont ete examines en utilisant des donnees geochimiques et isotopiques. Des eaux souterraines riches en I (>150 [micro]g/L) sont courantes parmi les eaux souterraines de type Na-Cl a de faibles elevations dans le socle rocheux dans des zones sur lesquelles reposent d'epaisses couches de sediments glaciaires. L'I serait relie a des argiles massives dans les sediments glaciaires reposant sur l'aquifere, deposees durant l'incursion postglaciaire de la mer de Champlain il y a 12-10 ka BP. L'analyse en composantes principales de l'I et de 18 autres parametres chimiques revele des correlations entre l'I, la salinite et des indicateurs d'oxydation microbienne de la matiere organique qui donnent a penser que l'intrusion d'eaux interstitielles salines influencees par la decomposition de matiere organique comme du phytoplancton marin dans les argiles massives est le principal processus modulant l'enrichissement en I de l'eau souterraine. Les rapports [.sup.129]I/[.sup.127]I dans les eaux premodernes vont de 460 x [10.sup.-14] a 5 x [10.sup.-14], des valeurs quasi marines, ce qui demontre que de l'I allochtone plus ancien derive du terrain sedimentaire paleozoique environnant a aussi contribue au reservoir d'I dans le bassin de la mer de Champlain. Les ages [.sup.14]C et les signatures de [delta][.sup.13]C pour le carbone organique dissous dans l'eau souterraine et le carbone organique dissemine dans les argiles glaciomarines font ressortir la presence de carbone organique terrestre provenant d'une source allochtone plus ancienne que l'incursion de la mer de Champlain, vraisemblablement transporte de pair avec l'I dans le bassin de la mer de Champlain par des eaux de fonte glaciaires. [Traduit par la Redaction], Introduction Geochemical analysis of shallow groundwaters ( The phenomenon of I enrichment in groundwater affects many regions of the world, including Japan (Kashiwagi et al. 2006; Togo et al. 2016), [...]

Porewater extractions and acid leachates of rock core from a 250 m thick sequence of low-permeability Ordovician-age shales and limestones, on the eastern flank of the Michigan Basin, were analysed for strontium isotope ratios in an attempt to infer porewater ages from observed [.sup.87]Sr/[.sup.86]Sr enrichments. The porewaters originated as Ordovician seawater, which subsequently mixed with evaporated Silurian seawater infiltrating from above, and, to some extent, with a deep brine--with an enriched [.sup.87]Sr/[.sup.86]Sr signature--from the underlying crystalline shield or deep basin. The porewater [.sup.87]Sr/[.sup.86]Sr ratios are more radiogenic than contemporaneous seawater but show no obvious correlation to those leached from the solid rock phases. Accepting that the initial [.sup.87]Sr/[.sup.86]Sr signatures in porewaters were dominated by Late Silurian brine, potentially with an additional deep brine component, the excess of radiogenic [.sup.87]Sr appears to represent ingrowth from [.sup.87]Rb decay over a time span of some 420 million years, approaching the depositional age of the rocks. Similarly, Rb/Sr errochron ages of acid leachates of solid phases, and the calculated initial [.sup.87]Sr/[.sup.86]Sr isotopic ratios, are consistent with a proposition that the calcites inherited their Sr from Ordovician seawater and were dolomitized shortly afterwards by infiltrating Mg-enriched evaporative brine, indicating long-term conservative behaviour for the enclosing carbonate rocks. The errochron for leachates from (alumino)silicates yields a high initial [.sup.87]Sr/[.sup.86]Sr, but with an errochron age of about 340 [+ or -] 48 Ma, likely owing to variable admixtures of diagenetic illite in the shales. Overall, the data provide evidence for a stable hydrologic regime since Paleozoic time. Des extractions d'eau interstitielle et de lixiviats acides de carottes de roches d'une sequence de 250 m d'epaisseur de shales et calcaires ordoviciens de faible permeabilite sur le flanc est du bassin du Michigan ont ete analysees pour en determiner les rapports d'isotopes du strontium, dans le but d'inferer les ages des eaux interstitielles sur la base de l'enrichissement observe en [.sup.87]Sr/[.sup.86]Sr. Les eaux interstitielles etaient a l'origine de l'eau de mer ordovicienne qui s'est ensuite melangee avec de l'eau de mer silurienne evaporee s'infiltrant par le haut et, dans une certaine mesure, avec une saumure profonde--caracterisee une signature en [.sup.87]Sr/[.sup.86]Sr enrichie--provenant du bouclier cristallin ou bassin profond sous-jacent. Les rapports [.sup.87]Sr/[.sup.86]Sr des eaux interstitielles sont plus radiogeniques que ceux de l'eau de mer contemporaine, mais ne presentent aucune correlation evidente avec les eaux lixiviees des phases solides des roches. En presumant que les signatures initiales de [.sup.87]Sr/[.sup.86]Sr dans les eaux interstitielles etaient dominees par des saumures d'age silurien tardif et, eventuellement, par une autre composante de saumure profonde, l'excedent de[.sup.87]Sr radiogenique semble representerle resultatde ladecomposition du[.sup.87]Rb sur une periode dequelque 420 millions d'annees, s'approchant de l'age du depot des roches. De meme, les ages erreurchrones de lixiviats acides issus de phases solides et les rapports [.sup.87]Sr/[.sup.86]Sr initiaux calcules concordent avec la proposition voulant que les calcites aient herite leur Sr d'eau de mer ordovicienne et ont ete dolomitisees peu apres par une saumure issue de l'evaporation enrichie en Mg, ce qui temoigne d'un comportement conservateur a long terme des roches carbonatees encaissantes. L'errochrone pour les lixiviats d'(alumino)silicates donne un [.sup.87]Sr/[.sup.86]Sr initial eleve, mais avec un age errochrone d'environ 340 [+ or -] 48 Ma, decoulant probablement de degres variables de melange d'illite diagenetique dans les shales. Globalement, les donnees offrent des preuves d'un regime hydrologique stable depuis le Paleozoique. [Traduit par la Redaction], Introduction A 400 m thick Upper Ordovician sedimentary sequence of shale (200 m) and underlying carbonate (200 m) situated on the eastern flank of the Michigan Basin comprise an aquiclude [...]

The use of fire as an offensive and defensive weapon on the colonial frontier in Australia has received little scholarly attention. This article aims to build on insights from current historiography about the customary use of fire by Aboriginal peoples within the borders of Victoria, Australia. Specifically, our aim is to highlight the historically significant role Aboriginal peoples' use of fire played in resisting the colonists in Victoria during the colonial period. By closely scrutinising documentary records it is possible to demonstrate that Aboriginal people used fire, both offensively and defensively, against the colonists. [ABSTRACT FROM AUTHOR]

The principal purpose of this study was to gain a greater understanding of the utilitarian and symbolic significance of koalas for Aboriginal communities in Queensland, Australia as recorded by colonists during the early period of colonization and the early twentieth century. It does this primarily through a close examination of the nineteenth-century and early twentieth-century archival records and contemporary publications that relate to Queensland Aboriginal peoples' associations with koalas. This paper is the third in a series investigating the historic and cultural importance of the koala according to the location in Australia. It likewise employs the historical method approach, which relies on identifying historical sources, evaluating their relative authority, and combining their testimony appropriately in order to construct an accurate and reliable picture of past events and environments. Through a critique of the published historical sources, the distribution of and the etymology of "koala" are briefly discussed before an examination is made of the animal's spiritual importance, associated cultural traditions, and simultaneous utilitarian role. Mirroring previous studies published by the authors on Victoria and New South Wales, we confirm that the predominately non-Aboriginal historical records reveal that koalas were hunted for food and their skin in some Queensland regions. It shall be seen that the ethno-historical records are inconclusive about the koala's distribution in Queensland, whether they were hunted across all of the state at the point of colonization and whether they were considered an integral food source in some regions. Furthermore, this study demonstrates that the extent to which they were used varied across regions and between language groups and was subject to certain rules, and that their spiritual significance can be traced directly to epic creation stories. The implications of this paper are consistent with the earlier New South Wales and Victorian studies: regional variations exist in Queensland in relation to the (pre-colonial, colonial and post-colonial) historic relationship between Aboriginal communities and koalas and that close consultation with Aboriginal communities needs to be taken into consideration when planning conservation measures relating to koalas. [ABSTRACT FROM AUTHOR]