WHY ARE THERE NO MAJOR Ni Cu SULFIDE DEPOSITS IN LARGE LAYERED MAFIC-ULTRAMAFIC INTRUSIONS?

Mafic - Ultramafic Rock Studies

Why large porphyry Cu deposits like high Sr/Y magmas?

Porphyry systems supply most copper and significant gold to our economy. Recent studies indicate that they are frequently associated with high Sr/Y magmatic rocks, but the meaning of this association remains elusive. Understanding the association between high Sr/Y magmatic rocks and porphyry-type deposits is essential to develop genetic models that can be used for exploration purposes. Here we ...

Possible Ni-rich Mafic-ultramafic Magmatic Sequence in the Columbia Hills: Evidence from the Spirit Rover

Introduction: The Spirit rover landed on geologic units of Hesperian age in Gusev Crater. The Columbia Hills rise above the surrounding plains materials, but orbital images show that the Columbia Hills are older [1, 2]. Spirit has recently descended the southeast slope of the Columbia Hills doing detailed measurements of a series of outcrops. The mineralogical and compositional data on these ro...

PRECAMBRIAN RESEARCH CENTER PROFESSIONAL WORKSHOP SERIES Field, Petrographic, and Mineralization Characteristics of Mafic Layered Intrusions

The Sonju Lake intrusion (SLI) is a 1200-m-thick, shallow-dipping, sheet-like intrusion that forms part of the Beaver Bay Complex (RI-58, Chapter 7). Although its exposed strike-length is only about 3 km (Fig. 3-1), the SLI has a distinctive aeromagnetic signature that can be traced for at least 20 km beneath a cover of glacial drift. The nearly constant width of its aeromagnetic anomaly sugges...

Why are there no insects in the open sea?

The air-filled tracheal respiratory system of insects prevents them from diving deeply in water. It is argued that this is the major factor in preventing insects from colonizing the open sea: they cannot descend sufficiently deeply in the daytime to escape being eaten by fish.