Abstract The Allchar Au-As-Sb-Tl deposit is situated in the western part of the Vardar zone, the main suture zone along the contact between the Adriatic and the Eurasian tectonic plates. It is spatially and temporally associated with a Pliocene (~5 Ma) postcollisional high-K calc-alkaline to shoshonitic volcano-plutonic center. The Allchar deposit shares many distinctive features with Carlin-type gold deposits in Nevada, including its location near a terrain-bounding fault in an area of low-magnitude extension and intense magmatism. The mineralization is mostly hosted in calcareous sedimentary rocks at intersections of high-angle faults in permeable stratigraphy. The alteration types (carbonate dissolution, silicification, and argillization), ore mineralogy (auriferous arsenian pyrite and marcasite, stibnite, realgar, orpiment, and lorandite), high Au/Ag ratios, and low base metal contents are also typical of Carlin-type gold deposits in Nevada. However, the Allchar deposit differs from Nevada Carlin-type gold deposits as follows: it is an isolated Au prospect with a close spatial and temporal relationship to a shoshonitic volcano-plutonic center in a mineral belt dominated by intrusion-related Cu-Au porphyry, skarn, and hydrothermal polymetallic deposits. The deposit is clearly zoned (proximal Au-Sb to distal As-Tl), it has a significantly higher Tl content, trace elements in pyrite and marcasite are homogeneously distributed, and synore dolomitization is a widespread alteration type. Gold mineralization is most abundant in the southern part of the deposit. It occurs mostly as invisible Au in disseminated pyrite or marcasite and as rare native Au grains. Gold mineralization is accompanied by intense decarbonatization and silicification. Fluid inclusions and the hydrothermal alteration mineral assemblage indicate that Au was deposited from hot (>200°C), saline (up to ~21 wt % NaCl equiv), moderately acidic (pH <5) fluids that carried traces of magmatic H 2 S and CO 2 . In the calcareous host rocks, mixing of such fluids with cool, dilute, near-neutral groundwater triggered deposition of Au and Fe sulfides. In Tertiary tuff, isocon analysis shows that sulfidation of preexisting Fe minerals was a critical factor for deposition of Au and Fe sulfides. Antimony mineralization prevails in the central part of the deposit, and it is mostly associated with dark-gray to black jasperoid. Stibnite, the most common Sb mineral in the Allchar deposit, occurs as fine-grained disseminations in jasperoid and as fine- to coarsely crystalline masses that fill vugs and fracture zones lined with drusy quartz. Fluid inclusions entrapped by stibnite-bearing jasperoid, quartz, and calcite crystals suggest that stibnite was deposited from more dilute and cooled fluids (aqueous-carbonic fluid inclusions: 6.0–3.5 wt % NaCl equiv, T h = 102°−125°C; aqueous fluid inclusions: 14.5 and 17.1 wt % NaCl equiv, T h = 120°−165°C). In contrast to stibnite, As sulfides (orpiment and realgar) and Tl mineralization are associated with argillic alteration. Fluid inclusions hosted by realgar, orpiment, dolomite, and lorandite record deposition from more dilute (2.6–6.9 wt % NaCl equiv) and relatively cold fluids (T H = 120°−152°C) enriched in K. Isocon diagrams show a tight link between Tl and the low-temperature argillic alteration as well as a significant correlation between Tl and K. The spatial relationship of Tl mineralization with dolomite suggests that Tl deposition was also promoted by neutralization of acidic fluids. The δ D and δ 18 O data obtained from gangue minerals and fluid inclusions indicate that magmatic fluid mixed with exchanged meteoric water at deep levels and with unexchanged meteoric water at shallow levels in the system. The δ 13 C and δ 18 O values of carbonate minerals and extracted fluid inclusions suggest mixing of carbonate rock buffered fluids with magmatic and atmospheric CO 2 . The sulfur isotope values of early disseminated pyrite and marcasite show that H 2 S was initially derived from diagenetic pyrite in sedimentary rocks. In contrast, Sb and As mineralization indicate a strong input of magmatic H 2 S during the main mineralization stage. Late-stage botryoidal pyrite and marcasite are depleted in 34 S, which indicates a diminishing magmatic influence and predominance of sulfur from sedimentary sources during the late-mineralization stage. Fractionation of isotopically light sulfide species from isotopically heavy sulfates due to oxidation under increased oxygen fugacity cannot be excluded.

Abstract: The total throw across a fault zone may not occur entirely on a single fault strand but may be distributed onto several strands or may be accommodated by distributed deformation within or adjacent to the fault zone. Here we conduct a quantitative analysis of the partitioning of throw into three components, the throw accommodated by: (a) the largest fault strand; (b) subsidiary faults; and (c) continuous deformation in the form of bed rotation in sympathy with the fault downthrow direction. This analysis is applied to seven seismic-scale fault zones at outcrop resolution (maximum throw 50 m) that were mapped over a four-year period during open-cast lignite mining within the late Miocene–Pliocene Ptolemais Basin, West Macedonia, Greece. The analysis shows that the fault zones offsetting the lignite–marl sequence are more localized at higher throws with progressively more of the total throw accommodated by the largest fault strand. Normal drag, which can account for up to 12 m of the total throw, accommodates a lower proportion of the total throw on larger faults. It appears that initial fault segmentation is the main control on the degree of, and spatial variation in, fault throw partitioning. Gold Open Access: This article is published under the terms of the CC-BY 3.0 license

Clear Lake core CL-73-4 records fluctuating abundances of oak pollen during the last glacial/interglacial cycle that correlate remarkably well with fluctuations in extensive pollen records from Grande Pile in France and Tenaghi Phillipon in Macedonia, as well as with the oxygen-isotope records from deep-sea cores. The record correlates less closely with other extensive records, including those for Lake Biwa, Japan, and Sabana de Bogotá, Colombia. Correlation of the record with the early Weichselian climatic sequence of northwestern Europe is excellent; both sequences show a series of five cryomer/thermomer fluctuations between the end of the last interglaciation (Eemian/Konocti, which is correlated here with the end of marine oxygen-isotope Stage 5e) and the onset of full continental glaciation at the end of Stage 5a. The fluctuations correlate both in their relative durations and in their relative amplitudes. The Clear Lake record also correlates with various North American sequences. The Sangamon interval of the mid-continent area correlates with the entire Konocti thermomer and early Pomo cryomer interval, and correlations with the glacial sequences of the Sierra Nevada and Rocky Mountains suggest that some Tahoe, Mono Basin, and Bull Lake moraines may be of Sangamon age. The proposed correlations of the Clear Lake record with other sequences have not been proved. The overall impression, however, is one of remarkable consistency, and it is likely that further work will provide more evidence in support of the sequence of five cryomer/thermomer cycles between the end of the last interglacial period and the onset of full glacial conditions about 70,000 years ago. This sequence is much more complicated than has been generally recognized, although parts of it have been known for many years. The sequence, which has now been found in several widely separated areas, should no longer be ignored.