Jurassic high heat production granites associated with the Weddell Sea rift system, Antarctica.

first_imgThe distribution of heat flow in Antarctic continental crust is critical to understanding continental tectonics, ice sheet growth and subglacial hydrology. We identify a group of High Heat Production granites, intruded into upper crustal Palaeozoic metasedimentary sequences, which may contribute to locally high heat flow beneath the West Antarctic Ice Sheet. Four of the granite plutons are exposed above ice sheet level at Pagano Nunatak, Pirrit Hills, Nash Hills and Whitmore Mountains. A new Usingle bondPb zircon age from Pirrit Hills of 178.0 ± 3.5 Ma confirms earlier Rbsingle bondSr and Usingle bondPb dating and that the granites were emplaced approximately coincident with the first stage of Gondwana break-up and the developing Weddell rift, and ~ 5 m.y. after eruption of the Karoo-Ferrar large igneous province. Aerogeophysical data indicate that the plutons are distributed unevenly over 40,000 km2 with one intruded into the transtensional Pagano Shear Zone, while the others were emplaced within the more stable Ellsworth-Whitmore mountains continental block. The granites are weakly peraluminous A-types and have Th and U abundances up to 60.7 and 28.6 ppm respectively. Measured heat production of the granite samples is 2.96–9.06 μW/m3 (mean 5.35 W/m3), significantly higher than average upper continental crust and contemporaneous silicic rocks in the Antarctic Peninsula. Heat flow associated with the granite intrusions is predicted to be in the range 70–95 mW/m2 depending on the thickness of the high heat production granite layer and the regional heat flow value. Analysis of detrital zircon compositions and ages indicates that the high Th and U abundances are related to enrichment of the lower-mid crust that dates back to 200–299 Ma at the time of the formation of the Gondwanide fold belt and its post-orogenic collapse and extension.last_img read more

Listen To The Biscuits Get Spooky Performing At A Haunted Lodge Eighteen Years Ago Today [Full Audio]

first_imgBack in 1999 on this date, The Disco Biscuits were gearing up to hit the Brookdale Lodge in Brookdale, California. The Brookdale Lodge has gained notoriety as a hotspot for paranormal encounters, and during their performance eighteen years ago, The Disco Biscuits honored the space’s haunted vibes with a spooky and spacey night of their early music.To open the show, the banter kicking off the night posed these questions to the crowd, “In this set of Disco Biscuits music, we’re endeavoring to answer the age old question, can the ghosts, not only can they see you physically, but can they read your mind? Can they read your every thought as you run from them or try to make peace with them?” Following this, the band kicked off a twenty-two-minute “Magellan” followed by “Eulogy” before dropping into a fifty-minute jam sequence featuring “Basis For A Day” into “Shem-Rah Boo” to round out the four-song first set. In set two, the majority of the set was encompassed in a “Nughuffer” sandwich, before throwing it back to the show opener, “Magellan,” with the live debut of the song’s reprise.You can listen to pristine audio from that show below, courtesy of Rich Steele.last_img read more