Geology topics

Research about New Brunswick

Source-linked reports with geographic coverage including New Brunswick.

5 recordsLinked to original sources

USGS2019

Petrology and geochemistry of migrated hydrocarbons associated with the Albert Formation oil shale in New Brunswick, Canada

Samples of the Carboniferous oil shale of the Albert Formation in New Brunswick, Canada, were examined using reflected white and fluorescence light microscopy, Rock-Eval pyrolysis, and ICP-MS (for elements). The presence of fractured filled solid bitumen in contact with, and within the Albert Formation oil shale, particularly in fractures at the right angle to the bedding of oil shale indicated that migrated oil had enough force to overcome the tensil strength of oil shale matrix, and penetrating the oil shale. Migrating fluid also caused thermal alteration of the oil shale matrix, as evident by the presence primary bitumen and oil droplets. The evidence of oil migration included the presence of solid bitumen and crystalline carbonates in contact with the immature oil shale. The low permeability oil shale acted as a seal/aquitard and created a diagenetic ‘front’ by reducing/slowing the advance of migrating oil, resulting in the formation of a reaction zone. Oil droplets were found in this reaction zone. Albertite was the only solid bitumen reported in the Albert Mine area previously. However, the present study found that migrated solid bitumen consisted of both soluble solid bitumen types such as gilsonite and glance-pitch, and non-soluble solid bitumen such as wurtzilite and albertite. The high hydrocarbon yield of oil shales in the Albert Mine area was due to the presence of various solid bitumen types associated with the oil shale and possibly slight thermal alteration that the oil shale experienced when it came in contact with migrating oil. The variation of Th/K ratio and TOC (wt%) indicates that most of oil shales from the Albert Mine area and within the vicinity of oil migration have higher content of TOC (17-25 wt%) as compared to the other Albert oil shales ( TOC=<10 %). The oil shales examined in this study were immature to marginally mature and had a wide range of hydrocarbon yield (2-213 L/Tonne). The highest hydrocarbon yield range (66-199 L/Tonne) was associated with oil shale outcrop samples collected in the Albert Mine itself, where the oil shale was heavily impregnated by migrated solid bitumen.

New Brunswick↗

USGS2016

Pockmarks in Passamaquoddy Bay, New Brunswick, Canada

Pockmarks are seafloor depressions associated with fluid escape ( Judd & Hovland 2007 ). They proliferate in the muddy seafloors of coastal Gulf of Maine and Bay of Fundy, where they are associated with shallow natural gas likely of biogenic origin ( Ussler et al. 2003 ; Rogers et al. 2006 ; Wildish et al. 2008 ). In North America, shallow-water pockmark fields are not reported south of Long Island Sound, despite the abundance of gassy, muddy estuaries. The absence of pockmarks south of the limit of North American glaciation suggests that local and regional heterogeneities, possibly related to glacial or sea-level history or bedrock geology, influence pockmark field distribution. In shallow-water embayments, such as Passamaquoddy Bay, New Brunswick, pockmarks can be large (>200 m diameter) and number in the thousands.

New Brunswick↗

USGS2016

Greenhouse gas fluxes from salt marshes exposed to chronic nutrient enrichment

We assessed the impact of nutrient additions on greenhouse gas fluxes using dark static chambers in a microtidal and a macrotidal marsh along the coast of New Brunswick, Canada approximately monthly over a year. Both were experimentally fertilized for six years with varying levels of N and P. For unfertilized, N and NPK treatments, average yearly CO 2 emissions (which represent only respiration) at the microtidal marsh (13, 19, and 28 mmoles CO 2 m -2 hr -1 , respectively) were higher than at the macrotidal marsh (12, 15, and 19 mmoles m -2 hr -1 , respectively, with a flux under the additional high N/low P treatment of 21 mmoles m -2 hr -1 ). Response of CH 4 to fertilization was more variable. At the macrotidal marsh average yearly fluxes were 1.29, 1.26, and 0.77 μmol CH 4 m -2 hr -1 with control, N, and NPK treatments, respectively and 1.21 μmol m -2 hr -1 under high N/low P treatment. At the microtidal marsh CH 4 fluxes were 0.23, 0.16, and -0.24 μmol CH 4 m -2 hr -1 in control, N, and NPK and treatments, respectively. Fertilization changed soils from sinks to sources of N 2 O. Average yearly N 2 O fluxes at the macrotidal marsh were -0.07, 0.08, and 1.70, μmol N 2 O m -2 hr -1 in control, N, NPK and treatments, respectively and 0.35 μmol m -2 hr -1 under high N/low P treatment. For the control, N, and NPK treatments at the microtidal marsh N 2 O fluxes were -0.05, 0.30, and 0.52 μmol N 2 O m -2 hr -1 , respectively. Our results indicate that N 2 O fluxes are likely to vary with the source of pollutant nutrients but emissions will be lower if N is not accompanied by an adequate supply of P (e.g., atmospheric deposition vs sewage or agricultural runoff). With chronic fertilization the global warming potential of the increased N 2 O emissions may be enough to offset the global cooling potential of the C sequestered by salt marshes.

New Brunswick↗

USGS1996

Upper Lower Cambrian depositional sequence in Avalonian New Brunswick

The Hanford Brook Formation (emended) is a thin (up to 42+ m), upper Lower Cambrian depositional sequence that is unconformably bounded by the lower Lower Cambrian (Random Formation) and the middle Middle Cambrian (Fossil Brook Member of the Chamberlain's Brook Formation). These stratigraphic relationships of the trilobite-bearing Hanford Brook Formation indicate deposition on the Avalonian marginal platform in the Saint John, New Brunswick, region and provide more evidence for a uniform, latest Precambrian–Cambrian epeirogenic history and cover sequence in Avalon. The Hanford Brook Formation is a deepening–shoaling sequence with ( i ) lower, transgressive sandstone deposited in episodically high-energy environments (St. Martins Member, new); ( ii ) highstand–regressive, dysaerobic mudstone – fine-grained sandstone with volcanic ashes (Somerset Street Member, new); and ( iii ) upper, regressive, planar and hummocky cross-stratified sandstone (Long Island Member, new). Trilobites are common in the distal Somerset Street Member, and ostracodes and brachiopods dominate the St. Martins and Long Island members. Condensation of the St. Martins Member and absence of the Long Island Member where the Random Formation and Fossil Brook Member are thinnest suggest onlap of the Hanford Brook and pronounced, sub-Middle Cambrian erosion across epeirogenically active blocks in southern New Brunswick.

New Brunswick↗

USGS1996

Reconstructing the Avalon continent: Marginal to inner platform transition in the Cambrian of southern New Brunswick

A west to east, marginal to inner Avalonian platform transition, comparable to that in southeast Newfoundland and southern Britain, is present in the Cambrian of southern New Brunswick. The Saint John–Caton's Island–Hanford Brook area lay on the marginal platform, and its thick, uppermost Precambrian–lower Lower Cambrian is unconformably overlain by trilobite-bearing, upper Lower Cambrian. An inner platform remnant is preserved in the Cradle Brook outlier 60 km northeast of Saint John. In contrast to the marginal platform sequences, the Cradle Brook outlier has a very thin lower Lower Cambrian and has middle Lower Cambrian strata (Bonavista Group) not present on the marginal platform. The Cradle Brook Lower Cambrian closely resembles inner platform successions in eastern Massachusetts and Trinity and Placentia bays, southeast Newfoundland. A limestone with Camenella baltica Zone fossils on Cradle Brook seems to be the peritidal limestone cap of the subtrilobitic Lower Cambrian known in Avalonian North America (Fosters Point Formation) and England (Home Farm Member).

New Brunswick↗