persistence and predictions of the remarkable warm anomaly in the northeastern pacific ocean during 2014 16 abstractin this work the evolution and prediction of the persistent and remarkable warm sea surface temperature anomaly ssta in the northeastern pacific during october 2013 june 2016 are examined based on experiments with an atmospheric model the possible contribution of sstas in different ocean basins to the atmospheric circulation anomalies is identified further through verifying the real time forecasts current capabilities in predicting such an extreme warm event with a state of the art coupled general circulation model are assessed during the long lasting warm event there were two warm maxima in the area averaged ssta around january 2014 and july 2015 respectively the warm anomaly originated at the oceanic surface and propagated downward and reached about 300 m model experiments forced by observed sst suggest that the long persistence of the atmospheric anomalies in the northeastern pacific as a whole may be partially explained by sst forcing particularly in the tropical pacific ocean ass

anatomy of north pacific decadal variability abstract a systematic analysis of north pacific decadal variability in a full physics coupled ocean atmosphere model is executed the model is an updated and improved version of the coupled model studied by latif and barnett evidence is sought for determining the details of the mechanism responsible for the enhanced variance of some variables at 20 30 yr timescales the possible mechanisms include a midlatitude gyre ocean atmosphere feedback loop stochastic forcing remote forcing or sampling error decadal variability in the model is expressed most prominently in anomalies of upper ocean streamfunction sea surface temperature sst and latent surface heat flux in the kuroshio oyashio extension koe region off japan the decadal signal off japan is initiated by changes in strength and position of the aleutian low the atmospheric perturbations excite sst anomalies in the central and eastern north pacific with opposing signs and canonical structure the atmospheric perturbations also change the ekm

source rock evaluation of middle jurassic coals northeast greenland by artificial maturation aspects of petroleum generation from coal paralic liptinite enriched coals and carbonaceous mudstones in northeast greenland constitute potential highly oil prone source rocks whereas the humic coals may be marginal source rocks the liptinite rich coals are dominated by resinite or fluorescing amorphous organic matter and alginite resulting in hydrogen index hi values generally above 300 and reaching up to 728 during artificial maturation up to 330 degreesc 72 hr the coals follow the maturation paths of kerogen types i and ii on an hi vs tmax diagram and calculations show that upon passage through the oil window roughly 85 of their generation potential is realized activation energy ea distributions with prominent principal ea values centered around 60 62 kcal mole and frequency factors from 5 855 x 1015 s 1 to 3 249 x 1016 s 1 strongly influence the generation characteristics from 300 to 330 degreesc 72 hr artificial maturation important changes include marked loss of liptinite fluorescence and increase in resinite reflectance small change in tmax significant decrease in hi pronounced increase in extract yields increased generation of saturates and generation of labile bitumen with low ea values these observations indicate significant bitumen petroleum formation from the coals during a relatively narrow temperature range which together with the petrographic composition may facilitate expulsion of a waxy crude oil the coals demonstrate that under certain depositional conditions highly prolific coal source rocks can form with the capacity not only to generate but also to expel liquid petroleum begin page 234

immature condensate from southeastern mediterranean coastal plain israel a highly unsaturated sulfur rich naphthenic condensate was discovered in association with dry biogenic gas in the upper tertiary of the southeastern mediterranean coastal plain of israel geologic and geochemical evidence suggests that this condensate was generated in thermally immature rocks similar material has been reported from the upper tertiary of the western mediterranean we suggest that the immature condensates were formed from resin rich terrestrially derived organic matter under an equivalent thermal regime marine material derived primarily from algae and bacteria will produce heavy crude rich in asphaltenes

atlantic multidecadal oscillation and northern hemisphere s climate variability proxy and instrumental records reflect a quasi cyclic 50 80 year climate signal across the northern hemisphere with particular presence in the north atlantic modeling studies rationalize this variability in terms of intrinsic dynamics of the atlantic meridional overturning circulation influencing distribution of sea surface temperature anomalies in the atlantic ocean hence the name atlantic multidecadal oscillation amo by analyzing a lagged covariance structure of a network of climate indices this study details the amo signal propagation throughout the northern hemisphere via a sequence of atmospheric and lagged oceanic teleconnections which the authors term the stadium wave initial changes in the north atlantic temperature anomaly associated with amo culminate in an oppositely signed hemispheric signal about 30 years later furthermore shorter term interannual to interdecadal climate variability alters character according to polarity of the stadium wave induced prevailing hemispheric climate regime ongoing research suggests mutual interaction between shorter term variability and the stadium wave with indication of ensuing modifications of multidecadal variability within the atlantic sector results presented here support the hypothesis that amo plays a significant role in hemispheric and by inference global climate variability with implications for climate change attribution and prediction

unusual resinite rich coals found in northeastern greenland and along the norwegian coast petrographic and geochemical composition abstract middle jurassic coals unusually rich in resinite liptinite are known in northeastern greenland from a few outcrops and from several erratic pieces in addition since the mid 1800 s a number of loose pieces of resinite rich coal the so called kvaefjord coal have been found along the norwegian coast in or close to the shore zone in places where it would have been impossible for the coal to originate from passing ships this study presents a comprehensive organic petrographic and geochemical investigation of two new pieces of resinite rich coal found on store koldewey in northeastern greenland a resinite rich core sample from the norwegian island andoya and two pieces of the norwegian kvaefjord coal the coals are thermally immature and contain an extraordinary high content of liptinite and in particular resinite 34 2 93 6 vol the two coal pieces from store koldewey and the core sample from andoya are compositionally comparable to the resinite liptinite rich middle jurassic coals that crop out on hochstetter forland and kuhn o in northeastern greenland the two loose pieces of kvaefjord coal are exceptionally rich in resinite and appear to be slightly different from the other coals albeit they are compositionally related the documentation of in situ resinite liptinite rich coals on andoya and the finding of loose pieces along the atlantic coast of norway indicate that formation of these unusual coals occurred regionally in the pre rift north atlantic region probably in peat forming mires with a yet unknown strongly resin producing vegetation established at the margins of a gradually northward prograding embayment formed during middle jurassic rifting between greenland and norway the unique maceral composition makes the coals excellent potential petroleum source rocks with hi values 400 mg hc g toc but the sketchy knowledge of the regional distribution of the coals combined with the probably restricted areal extent of the coal deposits limits their significance as an additional source rock in the north atlantic area

a reappraisal of kerogen formation abstract comparative microscopical and chemical studies of recognizable entities in kerogen and their extant counterparts suggest a new and simple mechanism of kerogen formation which clarifies the interrelationships between extant biomass kerogen and fossil fuels

a physics based approach of deep interseismic creep for viscoelastic strike slip earthquake cycle models most geodetic inversions of surface deformation rates consider the depth distribution of interseismic fault slip rate to be time invariant however some numerical simulations show down dip penetration of dynamic rupture into regions with velocity strengthening friction with subsequent up dip propagation of the locked to creeping transition recently bruhat segall 2017 developed a new method to characterize interseismic slip rates that allows slip to penetrate up dip into the locked region this simple model considered deep interseismic slip as a crack loaded at its down dip end and provided analytical expressions for stress drop within the crack slip and slip rate along the fault this study extends this approach to strike slip fault environments and includes coupling of creep to viscoelastic flow in the lower crust and upper mantle we employ this model to investigate interseismic deformation rates along the carrizo plain section of the san andreas fault this study reviews possible models elastic and viscoelastic for fitting horizontal surface rates using this updated approach we develop a physics based solution for deep interseismic creep which accounts for possible slow vertical propagation and investigate how it improves the fit of the horizontal deformation rates in the carrizo plain region

lower tertiary and upper cretaceous source rocks in louisiana and mississippi implications to gulf of mexico crude oil the lower tertiary sparta formation wilcox group and the midway group in southern louisiana include organic rich source facies that generate crude oil at relatively high thermal maturities the wilcox group is an important source of wilcox crude oil and regional kerogen variations explain two crude oil subfamilies wilcox crude oils in downdip areas of southern louisiana migrated short distances but long range lateral migration about 150 km best explains wilcox crude oils far updip from mature source rocks crude oils in oligocene and younger reservoirs in southern louisiana migrated vertically from deep lower tertiary source rocks some crude oils in upper cretaceous tuscaloosa reservoirs were emplaced by long range lateral migration from tuscaloosa source rocks g ven little evidence of upper tertiary source rocks and the overmaturity problems of mesozoic source rocks most crude oils in upper tertiary and pleistocene reservoirs of the gulf continental shelf are best explained by vertical migration from deep lower tertiary source rocks even so it is simplistic to assume an exclusive lower tertiary origin many tertiary and pleistocene crude oils of this study probably include an overprint of high maturity hydrocarbons from mesozoic sources

observations inferences and mechanisms of the atlantic meridional overturning circulation a review this is a review about the atlantic meridional overturning circulation amoc its mean structure temporal variability controlling mechanisms and role in the coupled climate system the amoc plays a central role in climate through its heat and freshwater transports northward ocean heat transport achieved by the amoc is responsible for the relative warmth of the northern hemisphere compared to the southern hemisphere and is thought to play a role in setting the mean position of the intertropical convergence zone north of the equator the amoc is a key means by which heat anomalies are sequestered into the ocean s interior and thus modulates the trajectory of climate change fluctuations in the amoc have been linked to low frequency variability of atlantic sea surface temperatures with a host of implications for climate variability over surrounding landmasses on intra annual timescales variability in amoc is large and primarily reflects the response to local wind forcing meridional coherence of anomalies is limited to that of the wind field on interannual to decadal timescales amoc changes are primarily geostrophic and related to buoyancy anomalies on the western boundary a pacemaker region for decadal amoc changes is located in a western transition zone along the boundary between the subtropical and subpolar gyres decadal amoc anomalies are communicated meridionally from this region amoc observations as well as the expanded ocean observational network provided by the argo array and satellite altimetry are inspiring efforts to develop decadal predictability systems using coupled atmosphere ocean models initialized by ocean data

shortening within underplated oceanic crust beneath the central california margin structures within a tectonically underplated layer of early miocene age oceanic crust indicate that the lower crust of offshore central california has been deformed under compression prior to the inception of the san andreas transform system along the continental margin shortening in the lower crust is inferred from the geometry of two structures the santa lucia monocline and the santa maria antiform delineated by an integrated interpretation of multichannel and wide angle seismic reflection data in conjunction with regional gravity data and teleseismic receiver functions the 700 km of multichannel seismic data and 300 km of wide angle seismic data from the 1986 pacific gas and electric edge seismic experiment form the primary data base used to establish the northwesterly trend and extent of the monocline and the wnw trend of the antiform in cross sectional view the santa lucia monocline is a 30 kink in the oceanic crust while the santa maria antiform is characterized by local thickening of the oceanic crust these structures are probably the result of convergence between the monterey and arguello microplates that took place as subduction along the margin waned the multichannel seismic reflection data image two miocene age shelf basins the santa lucia and offshore santa maria basins that formed within a transtensional stress regime the offshore santa maria basin directly overlies the santa maria antiform suggesting that either the upper and lower crustal stress regimes were completely decoupled in miocene time or that the two features formed in different places differential slip between the upper crust and lower crust may have been accommodated along a detachment zone located above oceanic crust convergence within the oceanic crust and apparent differential motion between upper and lower crust are indicative of the processes that can affect the transition from subduction to an oceanic continental transform zone

coal as a source rock for oil a review the geological debate about whether and to what extent humic coals have sourced oil is likely to continue for some time despite some important advances in our knowledge of the processes involved it is clear that not only liptinites but also perhydrous vitrinites have the potential to generate hydrocarbon liquids in the course of natural coalification some liptinites especially alginite cutinite and suberinite contain a higher proportion of aliphatic moieties in their structure than other liptinites such as sporinite and resinite and are therefore more oil prone it is of potential value to be able to predict the several environments of deposition in which coals with high liptinite contents or containing perhydrous vitrinites may have been formed review of the distribution of oil prone coals in time and space reveals that most are jurassic tertiary with key examples from australia new zealand and indonesia methods based both on experimental simulations and the examination of naturally matured samples have been used to determine the order of generation of hydrocarbons from different macerals results are not entirely consistent among the different approaches and there is much overlap in the ranges of degradation but it seems probable that in the natural environment vitrinites begin to generate early followed by labile liptinites such as suberinite then cutinite sporinite and finally alginite petroleum potential may be determined by experimental simulation of natural coalification or inferred through various micro techniques especially fluorescence and infrared ir spectroscopy or bulk techniques such as elemental analysis and 13c nmr spectroscopy the latter three techniques enable a measure of the polymethylene component of the coal which now appears to be one of the best available approaches for determining petroleum potential no method of experimental simulation of petroleum generation from coals is without criticism and comparative results are highly variable however hydrous pyrolysis confined pyrolysis and forms of open system hydrous pyrolysis approach acceptable simulations whether and to what degree generated liquid hydrocarbons are expelled has long been the central problem in oil from coal studies the structure of vitrinite was believed until recently to contain an interconnected microporous network in which generated oil would be contained until an expulsion threshold was attained recent studies show the pores are not interconnected combined with a dynamic model of pore generation it now seems that expulsion of hydrocarbons is best explained by activated diffusion of molecules to maceral boundaries and ultimately by cleats and fractures to coal seam boundaries the main reason for poor expulsion is the adsorption of oil on the organic macromolecule which may be overcome 1 if coals are thin and interbedded with clastic sediments or 2 if the coals are very hydrogen rich and generate large quantities of oil the existence of oil in vitrinite is attested to by solvent extractions fluorescence properties and by microscopic observations of oil and bitumen experimental simulation of expulsion of oil from coals has only recently been attempted the relative timing of release of generated co2 and ch4 could have considerable importance in promoting the expulsion of liquid hydrocarbons but the mechanism is unclear as it is universally agreed that dispersed organic matter dom in some shales readily generates and expels petroleum it is curious that few consistent geochemical differences have been found between coal macerals and dom in interbedded shales unambiguous evidence of expulsion from coals is limited and in particular only a few commercial oil discoveries can be confidently correlated to coals these include upper cretaceous fruitland formation coals in the usa from which oil is produced new zealand tertiary coals and middle jurassic coals from the danish north sea it is likely that coals have at least contributed to significant oil discoveries in the gippsland basin australia in the turpan basin china and in the kutei and ardjuna basins in indonesia but this remains unproven early reports that early jurassic coals in mid norway were a major source of the reservoired oils have been shown to be inaccurate none of the proposed rules of thumb for generation or expulsion of petroleum from coals seem particularly robust decisions on whether a particular coal is likely to have been an active source for oil should consider all available geological and geochemical information the assumptions made in computational models should be well understood as it is likely with new understandings of processes involved that some of these assumptions will be difficult to sustain

the petroleum geochemistry of canadian beaufort tertiary non marine oils abstract molecular isotopic and elemental data for a set of 28 paleogene and 3 cretaceous oils from the mackenzie delta and offshore canadian beaufort sea have been evaluated the depositional environment and organic matter characteristics of the source units for these oils have been predicted the paleogene oils of the canadian beaufort are molecularly distinctive and clearly contain a major land plant component oleanane and the 17 h and 17 h 24 28 bisnorlupanes are present as well as the following compound types 24 norlupanes and possibly higher homologues de a lupane noroleanenes norursene dehydroabietane 28 30 bisnorhopanes several molecular and isotopic characteristics are useful in assessing and ordering the extent of biodegradation and thermal maturation of these oils the cretaceous oils are separately sourced from the paleogene oils the latter oils comprise two distinct land plant derived genetic families distinguished by the presence absence of 24 28 bisnorlupanes 24 norursene 24 norlupane and 24 noroleanenes the kugmallit richards family contains each of these compound types and is considered to originate from the eocene richards formation in contrast lupanoids and noroleanenes are absent in oils of the reindeer moose channel family the occurrence of 28 30 bisnorhopane and or oleanane in these oils suggests a paleocene origin although these source rock predictions are supported by the available data they must be considered speculative until detailed molecular isotopic and elemental compositional data are available regionally for potential source rocks of the eocene and paleocene source units in the canadian beaufort

persistent fine scale fault structure and rupture development a new twist in the parkfield california story abstract we investigate the fine scale geometry and structure of the san andreas fault near parkfield ca and their role in the development of the 1966 and 2004 m6 earthquakes long term surface fault traces indicate that structural heterogeneities associated with secondary reverse and normal fault structures are present at both rupture tips near middle mountain and gold hill detailed analysis of almost 50 years of high resolution seismicity reveals a fault plane that has been twisted into a helicoid between middle mountain and gold hill numerical models support our conclusion that this shape is the result of long term torqueing of a strong stuck patch surrounded by a weak creeping region the changes in fault friction behavior and related geometric discontinuities act as barriers to rupture propagation of moderate size earthquakes at parkfield and as areas of concentrations where rupture initiates our study demonstrates also that smooth strike slip faults with large cumulative offset can form new fault segments at a late stage in their evolution

notes and correspondenceatmospheric effects on upper ocean temperature in the southeast tasman sea abstract the temperature profile in the ocean mixed layer was simulated using a turbulence closure model for a period of 18 years 1980 97 at a site in the southeast tasman sea 42 s 170 e the simulation was forced at the surface by a meteorological dataset derived from land station data sea surface temperature sst from the model was compared with the ncep 1 sst analysis beginning in 1982 the mean annual cycle and monthly anomalies in modeled sst agree with the ncep dataset in several respects modeled and observed sst anomalies are highly correlated with each other and are similar in overall magnitude timescale and phase however the model underpredicts the magnitude of sst anomalies in winter modeled and observed sst lagged correlation fields are similar with both showing a high correlation of sst anomalies in winter with anomalies in the previous spring the model has a pronounced recurrence mechanism that is anomalous temperatures in the deep mixed layer in spring remain below the sha

hydrocarbon geochemistry of the puget sound region ii sedimentary diterpenoid steroid and triterpenoid hydrocarbons cyclic components of the aliphatic hydrocarbon mixtures extracted from puget sound sediment cores include a suite of c19 and c20 diterpenoid hydrocarbons of which fichtelite sandaracopimaradiene and isopimaradiene have been identified although apparently also derived from vascular plants these diterpenoid hydrocarbons have relative abundances distinctly different from the co existing plant wax n alkane suite five c27 c28 and c29 diasteranes and four c29 c30 and c31 17 h 21 h hopanes occur in relatively constant proportion as components of a highly weathered fossil hydrocarbon assemblage these chromatographically resolved cycloalkanes along with the strongly covarying unresolved complex mixture have been introduced to puget sound sediments from adjacent urban centres at increasing levels over the last 100 yr in the absence of any major oil spill naturally occurring triterpenoid hydrocarbons including hop 22 29 ene diploptene are also present a new group of c30 polyenes has been detected which contains compounds apparently structurally related to a co existing bicyclic c25 diene and to c20 and c25 acyclic multibranched hydrocarbons described in a previous paper barrick et al 1980

controls on the oil and gas potential of humic coals abstract humic coals are highly heterogeneous both with respect to maceral content and chemical composition although the oldest known humic coals albeit gas prone are of devonian age the majority of humic coals capable of generating and expelling non volatile oil are of cretaceous and tertiary age from australia new zealand and southeast asia in contrast the middle jurassic humic coals of the sleipner and hugin formations in the south viking graben of the north sea are primarily gasprone but have the capability to expel aliphatic rich volatile oil these coals have toc contents up to 80 and hydrogen indices hi ranging from 200 to 400 they are vitrinite rich with some containing up to 45 inertinite liptinite concentrations are generally around 10 20 chiefly as spores pollen and abundant resinite the main control on the oil potential of humic coals is the concentration of long chain aliphatic hydrocarbons in the coal matrix although the aliphatics have a high h c ratio the inference on hydrogen content from the rock eval pyrolysis hi value can be misleading for hi values below 500 mg hc g oc there is no relation between hi and the potential of the coals to generate non volatile oil consequently the hi is a poor indicator of the non volatile oil potential of humic coals a more robust indicator is the relative amount of c8 aliphatic groups also the bulk measure of liptinite content may also prove misleading when assessing the oil potential of coals high resinite concentrations can lead to an overprediction of the non volatile oil potential as they contribute significantly to the hi value but will generate primarily volatile aromatic rich oils expulsion from the sleipner and hugin coals appears to have occurred in a gaseous phase with preferential release of short chain alkanes

role of the gulf stream and kuroshio oyashio systems in large scale atmosphere ocean interaction a review abstract ocean atmosphere interaction over the northern hemisphere western boundary current wbc regions i e the gulf stream kuroshio oyashio and their extensions is reviewed with an emphasis on their role in basin scale climate variability sst anomalies exhibit considerable variance on interannual to decadal time scales in these regions low frequency sst variability is primarily driven by basin scale wind stress curl variability via the oceanic rossby wave adjustment of the gyre scale circulation that modulates the latitude and strength of the wbc related oceanic fronts rectification of the variability by mesoscale eddies reemergence of the anomalies from the preceding winter and tropical remote forcing also play important roles in driving and maintaining the low frequency variability in these regions in the gulf stream region interaction with the deep western boundary current also likely influences the low frequency variability surface heat fluxes damp the low frequency sst anomalies ove

hydrocarbon potential of pennsylvanian coal in bohai gulf basin eastern china as revealed by hydrous pyrolysis abstract a hydrous pyrolysis experiment was performed using pennsylvanian brown coal with a vitrinite reflectance vr 0 of 0 56 from a coal mine at the southwest corner of the bohai gulf basin eastern china to evaluate the hydrocarbon potential of the coal the coal sample is vitrinite rich 74 5 and inertinite poor 16 7 with liptinite content of 8 8 much of the vitrinite in the sample consists of hydrogen rich vitrinite collodetrinite hydrous pyrolysis was performed at 200 c 230 c 260 c 290 c 320 c and 350 c for 72 h separately yields of both total liquid pyrolysates and expelled oil increased with temperature before reaching their maximum production of 17 27 kg t coal and 14 57 kg t coal at the same temperature of 320 c vr 0 1 18 and decreased afterwards gaseous products increased sharply at 320 c and tended to increase even at the highest experimental temperature 350 c vr 0 1 53 results show that the coal has not only a certain oil generation potential but also a large capacity for gas production and a high expulsion efficiency oil potential of the coal is attributed to its depositional environment which was transitional from shallow marine to coastal plain or swamp during middle to late pennsylvanian the coal was protected from oxidation under water after deposition experimental results indicate that this pennsylvanian coal could have contributed to oil gas accumulation in the bohai gulf basin

winter to winter recurrence of sea surface temperature salinity and mixed layer depth anomalies abstract the mean seasonal cycle of mixed layer depth mld in the extratropical oceans has the potential to influence temperature salinity and mixed layer depth anomalies from one winter to the next temperature and salinity anomalies that form at the surface and spread throughout the deep winter mixed layer are sequestered beneath the mixed layer when it shoals in spring and are then re entrained into the surface layer in the subsequent fall and winter here we document this re emergence mechanism in the north pacific ocean using observed ssts subsurface temperature fields from a data assimilation system and coupled atmosphere ocean model simulations observations indicate that the dominant large scale sst anomaly pattern that forms in the north pacific during winter recurs in the following winter the model simulation with mixed layer ocean physics reproduced the winter to winter recurrence while model simulations with observed ssts specified in the tropical pacific and a 50 m slab in the north pacific did not this difference between the model results indicates that the winter to winter sst correlations are the result of the re emergence mechanism and not of similar atmospheric forcing of the ocean in consecutive winters the model experiments also indicate that sst anomalies in the tropical pacific associated with el nino are not essential for re emergence to occur the recurrence of observed sst and simulated sst and sss anomalies are found in several regions in the central north pacific and are quite strong in the northern 50 n part of the basin the winter to winter autocorrelation of sss anomalies exceed those of sst since only the latter are strongly damped by surface fluxes the re emergence mechanism also has a modest influence on mld through changes in the vertical stratification in the seasonal thermocline

double difference tomography the method and its application to the hayward fault california we have developed a double difference dd seismic tomography method that makes use of both absolute and relative arrival times by reducing systematic errors using the more accurate relative arrival times the method produces an improved velocity model simultaneously it yields event locations of a quality equivalent to those of the dd location method while avoiding simplifying assumptions of that method we test this method on a synthetic dataset and find that it produces a more accurate velocity model and event locations than standard tomography we also test this method on a hayward fault california earthquake dataset spanning 1984 1998 the earthquakes relocated by this method collapse to a thin line along the fault trace consistent with previous results the dd velocity model has sharper velocity contrasts near the source region than the standard tomography model

immature oil and condensate modification of hydrocarbon generation model for terrestrial organic matter petroleum has been found in canadian frontier basins in reservoirs which have undergone low levels of thermal alteration vitrinite reflectance 0 6 ro paraffin indices stable carbon and hydrogen isotope contents pristane to nc17 ratios and diterpenoid biologic markers have been used to assess the level of maturity of the hydrocarbons in the reservoir independently of the level of maturity of the reservoir itself and of the surrounding shale units in the tertiary of the beaufort mackenzie basin naphthenic oils and condensates have been generated from terrestrially derived organic matter in source rocks juxtaposed with the reservoir at reflectance levels of 0 4 to 0 6 ro however condensates discovered in reservoirs which are th rmally immature on the labrador shelf have undergone extensive vertical migration and can be classed as conventional mature to overmature condensates hydrocarbons discovered in the lower cretaceous of the beaufort mackenzie basin and also those of the scotian shelf are more or less in place in that they are at a level of thermal alteration about equivalent to that of the reservoirs in which they are trapped the source for the early oils and condensates is considered to be resinite occurring dispersed in coal fragments the proportion of resinite liptinite and vitrinite in the organic matter of terrestrial source rocks strongly controls both the level of thermal alteration necessary for the section to function as an effective source rock and the ultimate product gas oil or condensate which will be generated

eocene amber from the pacific coast of north america fossil plant resins are common in late cretaceous rocks of north america and in oligocene and younger sediments of equatorial and southern hemisphere locations the scarcity of amber in early tertiary rocks however poses puzzling geological questions detailed examination of mid eocene amber bearing sediments from coalmont british columbia and seattle washington indicates that resins were produced by taxodiaceous conifers with metasequoia occidentalis being the most likely source laboratory heating experiments and paleotemperature analysis of these sediments based on coal rank and vitrinite reflectance suggest that burial temperatures may significantly affect infrared spectra of amber a phenomenon not previously recognized by researchers who have long used spectral characteristics to speculate on the botanical origin of fossil resins the occurrence of amber in mid eocene rocks of the pacific northwest arkansas and southern california suggests that resin production ended as the climate of north america cooled during the mid tertiary and that late tertiary amber was produced by flowering tropical plants not present in the eocene forests this evolutionary record appears somewhat different from that of western europe where progressive southward migration of coniferous amber forests occurred during mid tertiary time

the petroleum potential of some tertiary lignites from northern greece as determined using pyrolysis and organic petrological techniques abstract oil condensate and gas have recently been discovered in the thermaikos gulf area of northern greece the source of these hydrocarbons is not known although there is a possibility that more mature equivalents of certain tertiary brown coals and lignites may be responsible a contribution from tertiary terrestrial organic matter to the epanomi oil is supported by its biomarker distributions especially the predominance of triterpenoid compounds other than hopanes in the m z 191 mass fragmentogram in this study the hydrocarbon potential of a suite of greek tertiary lignites is first examined using rock eval analysis three samples are then further investigated using organic petrography and gas chromatography gc and gas chromatography mass spectrometry gc ms of the extracted hydrocarbon fractions as well as by hydrous pyrolysis an intermontane lignite 6og 5 contains fluorescing huminite together with resinite on extraction this resinite is found to be of predominantly diterpenoid origin rock eval and hydrous pyrolysis support previous proposals that diterpenoid resinite needs a lower activation energy to generate hydrocarbons than most other types of organic matter a sample of a lignite deposited in a deltaic environment mm 3 contains a more diverse collection of liptinite macerals with resinite again predominating the resinite appears to be mostly of triterpenoid and sesterterpenoid origin the best hydrocarbon potential is shown by a sample deposited in a lagoonal environment kas 3 little discrete resinite is observed in this sample but it does contain abundant fluorescing huminite although it has a low s 1 s 1 s 2 ratio it gives a high yield on solvent extraction during which a significant fraction of the s2 is removed the fluorescence of the huminite after extraction is greatly reduced the hydrocarbons of the extract are believed to be predominantly derived from triterpenoid resinite unlike the pyrolysates of the other two lignites but in common with the epanomi oil the triterpenoids in the kas 3 pyrolysate are dominated by resin derived compounds rather than hopanes this and other similarities between the composition of the pyrolysates of kas 3 and the oil support the possibility that a more mature equivalent of this lignite could be the source of the epanomi oil

hydrocarbon generation from deltaic and intermontane fluviodeltaic coal and coaly shale from the tertiary of texas and carboniferous of nova scotia abstract selected samples of coal and coaly shale from southeastern texas depositional environment deltaic age paleocene eocene ro 0 25 0 75 and nova scotia depositional environment intermontane swamp delta and lacustrine age carboniferous westphalian a d ro 0 67 0 70 were analyzed by fluorescence microscopy rock eval pyrolysis nmr anhydrous pyrolysis temperature programed and flash and hydrous pyrolysis to evaluate the hydrocarbon potential and hydrocarbon types based on maceral assemblages palynofacies and hydrocarbon potential these coal and coaly shale samples are classified as humic mixinitic mixed and sapropelic compared to humic and sapropelic as defined by stach et al coal petrology gebruder borntraeger berlin 1982 mixinitic or mixed coal and coaly shale containing mainly humodetrinite and lipodetrinite generated more than 10 pyrolysate expelled oil oil in wash fraction remaining coal extract and show a bimodal n alkane distribution derived from cutinite suberinite and alginite pyrolysis of humotelinite humocollinite rich and liptinite poor humic coals generated low amounts

southern california hypocenter relocation with waveform cross correlation part 1 results using the double difference method we present the results of relocating 327 000 southern california earthquakes that occurred between 1984 and 2002 we apply time domain waveform cross correlation for p and s waves between each event and 100 neighboring events identified from the catalog based on a 3d velocity model to simplify the computation we first divide southern california into five polygons such that there are 100 000 events or less in each region the polygon boundaries are chosen to lie in regions of sparse seismicity we calculate and save differential times from the peaks in the cross correlation functions and use a spline interpolation method to achieve a nominal timing precision of 0 001 sec these differential times together with existing p and s phase picks are input to the double difference program of waldhauser and ellsworth 2000 2002 to calculate refined hypocenters we divide the southern california region into grid cells and successively relocate hypocenters within each grid cell the overall resulting pattern of seismicity is more focused than the previously determined pattern from 1d or 3d models the new improved locations are more clustered in many cases by a factor of two or three and often show clear linear alignments in particular the depth distribution is improved and less affected by layer boundaries in velocity models or other similar artifacts

north pacific subtropical mode water volume decrease in 2006 09 estimated from argo observations influence of surface formation and basin scale oceanic variability abstractanalysis of argo temperature and salinity profiles gridded at 0 5 0 5 resolution for 2005 12 shows a strong north pacific subtropical mode water npstmw volume and density decrease during 2006 09 in this time period upper ocean temperature stratification and potential vorticity pv all increased within the region in and around the npstmw low pv pool contributing to the npstmw volume decrease in two ways i the volume of water satisfying the low pv constraint that is part of the mode water definition decreased and ii some water that was initially in the npstmw density range 25 0 25 5 kg m 3 was transformed into lighter water both changes in density and in pv in the npstmw region were a manifestation of basinwide changes a positive pv anomaly started to propagate westward from the central pacific in 2005 followed by a negative density anomaly in 2007 which caused a dramatic npstmw volume and density decrease a walin estimate of surface formation in the npstmw density ran

controls on sediment distribution in the coastal zone of the central california transform continental margin usa abstract we use 10 000 km of high resolution seismic reflection data together with multibeam bathymetry to document complex and highly variable post last glacial maximum lgm sediment distribution and thickness in the coastal zone 10 m isobath to 5 6 km offshore along a 800 km section of central california s transform continental margin sediment thickness ranges from 0 seafloor bedrock to 64 m with a mean of 8 7 m we delineate 25 coastal zone sediment domains and group them based on common geomorphology and sediment occurrence thickest sediment occurs in mountain front and large river domains which comprise 14 5 and 7 9 of the coastal zone and contain 30 1 and 18 2 of coastal zone sediment respectively in contrast small river domains and sediment poor shelf domains comprise 50 7 and 15 7 of the coastal zone and contain 18 4 and 12 7 of its sediment the distribution and thickness of post lgm sediment in the coastal zone is controlled by a combination of tectonics sediment supply and eustasy sediment is derived from a tectonically controlled coastal landscape of rapidly uplifting mountain fronts more slowly uplifting marine terraces and fault bounded headlands and alluvial estuarine troughs sediment supply is maximized along steep landslide prone mountain fronts and at the mouths of large watersheds and minimized along lower relief terraced coastal landscape drained by smaller rivers and creeks in the offshore coastal zone tectonics generates local uplifts and basins and influences shelf width and gradient as well as the locations of some shelf incised submarine canyons sea level rise raises base level drowns estuaries creates accommodation space on the shelf amount based on gradient and isolates the heads of many submarine canyons at or near the shelfbreak comparison of shelf sediment volumes with estimates of unaltered watershed sediment supply reveals that a relatively small proportion of post lgm sediment supply is preserved on the shelf offshore of some of the largest rivers sediments deposited in shoreline and shelf environments have limited preservation potential and the most complete long term geologic record of the post lgm transgression and highstand is likely represented in slope and submarine fan deposits

comparison of generative capacities for bitumen and gas between carboniferous coals from donets basin ukraine and a cretaceous coal from sabinas piedras negras basin mexico during artificial maturation in confined pyrolysis system abstract the goal of this work is to study the ability of two immature carboniferous coals from donets basin ukraine to act as source for oil heating experiments in confined medium were performed to compare the thermal behavior of these coals 1l1 dim r r 0 55 h c at 0 79 and 2c10yd r r 0 65 h c at 0 80 relative to a mature cretaceous coal from sabinas basin olmos r r 0 92 h c at 0 77 macerals analysis carried out on starting materials showed that olmos is exhausted in liptinite contrary to 2c10yd 20 vol and 1l1dim 6 vol the vitrinite content is lower for 2c10yd 59 vol than for olmos 84 vol and 1l1dim 80 vol solid bitumen occurs often dispersed in the raw coals both petrographic and geochemical analyses on starting materials revealed that the selected carboniferous donets coals have better potentialities for bitumen generation than the cretaceous sabinas coal the presence of long chain n alkanes n c 8 in the pyrolysis gc chromatograms indicates that the two raw carboniferous coals from donets basin can yield non volatile hydrocarbons under further thermal maturation it is speculated that some vitrinite macerals present in hydrogen rich carboniferous coals from donets basin can act as source rocks for oil as a matter of fact results showed that the oil window occurs between 1 0 r r and 2 0 r r for both cretaceous sabinas and carboniferous donets coals during confined pyrolysis as expected from geochemical and petrographic analyses of starting samples the carboniferous donets coals yielded more bitumen and hydrocarbons than cretaceous sabinas coal during artificial maturation low proportions of solid bitumen r r and 1 5 r r during confined pyrolysis of coals two solid bitumen groups have been identified which correspond to distinct phases of neo formation the drop in the solid bitumen content at higher ranks indicates that it contributes to generation of gas during experimental simulation moreover their morphology and porosity change with the level of maturity the porosity of the vitrinite matrix increases as well as the pore size with increasing maturity a relationship has been observed between the porosity and the weight loss the higher pore content of carboniferous donets coals is correlated with a higher generation of gas compared to cretaceous sabinas coal

modeling distributed seismicity for probabilistic seismic hazard analysis implementation and insights with the openquake engine abstract in any probabilistic seismic hazard model the earthquake activity that cannot be associated with well characterized fault structures is taken into account as seismicity distributed over a geographical region ground motion prediction equations gmpes are generally based on predictor variables describing the spatial extension of a rupture the approach taken to model rupture finiteness can therefore bias the estimation of seismic hazard we study the effect of rupture finiteness in modeling distributed seismicity using the openquake oq engine the open source software for seismic hazard and risk assessment promoted by the global earthquake model initiative for a simple test case we show how the inclusion of rupture finiteness with respect to the point rupture approximation leads to a significant increase in the probabilities of exceedance for a given level of motion we then compare the oq engine with the calculation software developed by the u s geological survey national seismic hazard mapping project by considering a gridded seismicity model for california we show how different approaches for modeling finite ruptures affect seismic hazard estimates we show how sensitivity to rupture finiteness depends not only on the spatial distribution of activity rates but also on the gmpe model considering two sites in los angeles and san francisco we show that for a return period of 475 years the percent difference in the associated ground motion levels when using point and finite ruptures ranges from 19 to 46 for a return period of 2475 years the difference ranges from 29 to 58

stress triggering in thrust and subduction earthquakes and stress interaction between the southern san andreas and nearby thrust and strike slip faults 1 we argue that key features of thrust earthquake triggering inhibition and clustering can be explained by coulomb stress changes which we illustrate by a suite of representative models and by detailed examples whereas slip on surface cutting thrust faults drops the stress in most of the adjacent crust slip on blind thrust faults increases the stress on some nearby zones particularly above the source fault blind thrusts can thus trigger slip on secondary faults at shallow depth and typically produce broadly distributed aftershocks short thrust ruptures are particularly efficient at triggering earthquakes of similar size on adjacent thrust faults we calculate that during a progressive thrust sequence in central california the 1983 mw 6 7 coalinga earthquake brought the subsequent 1983 mw 6 0 nunez and 1985 mw 6 0 kettleman hills ruptures 10 bars and 1 bar closer to coulomb failure the idealized stress change calculations also reconcile the distribution of seismicity accompanying large subduction events in agreement with findings of prior investigations subduction zone ruptures are calculated to promote normal faulting events in the outer rise and to promote thrust faulting events on the periphery of the seismic rupture and its downdip extension these features are evident in aftershocks of the 1957 mw 9 1 aleutian and other large subduction earthquakes we further examine stress changes on the rupture surface imparted by the 1960 mw 9 5 and 1995 mw 8 1 chile earthquakes for which detailed slip models are available calculated coulomb stress increases of 2 20 bars correspond closely to sites of aftershocks and postseismic slip whereas aftershocks are absent where the stress drops by more than 10 bars we also argue that slip on major strike slip systems modulates the stress acting on nearby thrust and strike slip faults we calculate that the 1857 mw 7 9 fort tejon earthquake on the san andreas fault and subsequent interseismic slip brought the coalinga fault 1 bar closer to failure but inhibited failure elsewhere on the coast ranges thrust faults the 1857 earthquake also promoted failure on the white wolf reverse fault by 8 bars which ruptured in the 1952 mw 7 3 kern county shock but inhibited slip on the left lateral garlock fault which has not ruptured since 1857 we thus contend that stress transfer exerts a control on the seismicity of thrust faults across a broad spectrum of spatial and temporal scales

geometry and late pleistocene displacement of the shoreline and oceano fault zones san luis obispo bay californiageometry and late pleistocene displacement of the shoreline and oceano fault zones

a linear inverse model of tropical and south pacific seasonal predictability a multivariate linear inverse model lim is developed to demonstrate the mechanisms and seasonal predictability of the dominant modes of variability from the tropical and south pacific oceans we construct a lim whose covariance matrix is a combination of principal components derived from tropical and extratropical sea surface temperature and south pacific ocean vertically averaged temperature anomalies eigen decomposition of the linear deterministic system yields stationary and or propagating eigenmodes of which the least damped modes resemble el nino southern oscillation enso and the south pacific decadal oscillation spdo we show that although the oscillatory periods of enso and spdo are distinct they have very close damping time scales indicating that the predictive skill of the surface enso and spdo is comparable the most damped noise modes occur in the midlatitude south pacific ocean reflecting atmospheric eastward propagating rossby wave train variability we argue that these ocean wave trains occur due to the high frequency atmospheric variability of the pacific south american pattern imprinting onto the surface ocean the enso spring predictability barrier is apparent in lim predictions initialized in march may mam but displays a significant correlation skill of up to 3 months for the spdo the predictability barrier tends to appear in june september jas indicating remote but delayed influences from the tropics we demonstrate that subsurface processes in the south pacific ocean are the main source of decadal variability and further that by characterizing the upper ocean temperature contribution in the lim the seasonal predictability of both enso and the spdo variability is increased

a model for neogene crustal rotations transtension and transpression in southern california two episodes of crustal rotation have occurred in the regions of southern california and the mojave desert since the beginning of miocene time an early miocene episode of clockwise crustal rotation is associated with widespread north south to north northeast south southwest crustal extension throughout southeast california and western arizona this episode is apparently related to changing subduction parameters of the farallon plate a middle miocene and later episode of clockwise rotation in the transverse ranges and bordering areas is related to shear between the pacific and north american plates in both episodes clockwise crustal rotations first occur in a deforming zone which has a component of extension across its trend and shear along its trend the effects of extension are most pronounced in the earlier episode but clear in the later one also the pacific north american deforming zone began contracting in width during pliocene time but clockwise rotations continued and are probably in progress today

analog models of restraining stepovers in strike slip fault systems scaled sandbox models have successfully simulated the geometries and progressive evolution of antiformal pop up structures developed in a weak sedimentary cover above restraining stepovers in offset sinistral strike slip fault systems in rigid basement models were run both with and without synkinematic sedimentation which was added incrementally to cover the growing antiformal structures vertical and horizontal sections of the completed models permit the full three dimensional 3 d structure of the pop ups to be analyzed in detail three representative end member experiments are described 30 underlapping restraining stepovers 90 neutral restraining stepovers and 150 overlapping restraining stepovers the experimental pop ups are typically sigmoidal to lozenge shaped antiformal structures having geometries that are dependent on both the stepover angle and stepover width in the underlying basement faults underlapping restraining stepovers typically form elongate lozenge shaped pop ups 90 neutral restraining stepovers produce shorter squat rhomboidal pop ups and overlapping restraining stepovers produce sigmoidal antiformal pop ups trans pop up cross fault systems are characteristic at large displacements on the basement fault system above the offset principal displacement zones the pop ups are commonly small narrow positive flower structures whereas in the stepover region they widen out and become markedly asymmetric this pop up asymmetry switches across the center of the stepover where the pop ups are largely symmetical maximum rotations measured within the central highly uplifted region of the pop ups increase from 7 counterclockwise for the underlapping 30 stepovers to 14 counterclockwise for the neutral 90 stepovers to 16 counterclockwise for the overlapping 150 stepovers in models where no synkinematic sediments were added during deformation the pop up structures are bound by convex flattening upward oblique slip reverse fault systems that link downward to the offsets in the basement fault system in contrast in the begin page 234 experiments where synkinematic sediments were added incrementally during deformation the pop ups are formed by oblique slip reverse faults that steepen upward into the synkinematic strata with the formation of fault propagation growth folds the analog models are compared with natural examples of pop up structures and show strong similarities in structural geometries and stratal architectures these models may provide structural templates for seismic interpretation of complex contractional structures in offset strike slip fault systems

crustal structure and fault geometry of the 2010 haiti earthquake from temporary seismometer deployments haiti has been the locus of a number of large and damaging historical earthquakes the recent 12 january 2010 mw 7 0 earthquake affected cities that were largely unprepared which resulted in tremendous losses it was initially assumed that the earthquake ruptured the enriquillo plantain garden fault epgf a major active structure in southern haiti known from geodetic measurements and its geomorphic expression to be capable of producing m 7 or larger earthquakes global positioning systems gps and interferometric synthetic aperture radar insar data however showed that the event ruptured a previously unmapped fault the leog ne fault a north dipping oblique transpressional fault located immediately north of the epgf following the earthquake several groups installed temporary seismic stations to record aftershocks including ocean bottom seismometers on either side of the epgf we use data from the complete set of stations deployed after the event on land and offshore to relocate all aftershocks from 10 february to 24 june 2010 determine a 1d regional crustal velocity model and calculate focal mechanisms the aftershock locations from the combined dataset clearly delineate the leog ne fault with a geometry close to that inferred from geodetic data its strike and dip closely agree with the global centroid moment tensor solution of the mainshock but with a steeper dip than inferred from previous finite fault inversions the aftershocks also delineate a structure with shallower southward dip offshore and to the west of the rupture zone which could indicate triggered seismicity on the offshore trois baies reverse fault we use first motion focal mechanisms to clarify the relationship of the fault geometry to the triggered aftershocks

characterizing thermogenic coalbed gas from polish coals of different ranks by hydrous pyrolysis abstract to provide a better characterization of origin and volume of thermogenic gas generation from coals hydrous pyrolysis experiments were conducted at 360 c for 72 h on polish coals ranging in rank from lignite 0 3 r r to semi anthracite 2 0 r r under these conditions the lignites attained a medium volatile bituminous rank 1 5 r r high volatile bituminous coals attained a low volatile bituminous rank 1 7 r r and the semi anthracite obtained an anthracite rank 4 0 r r hydrous pyrolysis of a coal irrespective of rank provides a diagnostic 13 c value for its thermogenic hydrocarbon gases this value can be used quantitatively to interpret mixing of indigenous thermogenic gas with microbial methane or exogenous thermogenic gas from other sources thermogenic methane quantities range from 20 dm 3 kg of lignite 0 3 r r to 0 35 dm 3 kg of semi anthracite 2 0 r r at a vitrinite reflectance of 1 7 r r approximately 75 of the maximum potential for a coal to generate thermogenic methane has been expended at a vitrinite reflectance of 1 7 r r more than 90 of the maximum potential for a coal to generate co 2 has been expended assuming that these quantities of generated co 2 remain associated with a sourcing coal bed as uplift or erosion provide conditions conducive for microbial methanogenesis the resulting quantities of microbial methane generated by complete co 2 reduction can exceed the quantities of thermogenic methane generated from the same coal bed by a factor of 2 5

dynamics of sea surface temperature anomalies in the southern ocean diagnosed from a 2d mixed layer model we analyze the processes responsible for the generation and evolution of sea surface temperature anomalies observed in the southern ocean during a decade based on a 2d diagnostic mixed layer model in which geostrophic advection is prescribed from altimetry anomalous air sea heat flux is the dominant term of the heat budget over most of the domain while anomalous ekman heat fluxes account for 20 40 of the variance in the latitude band 40 60 s in the acc pathway lateral fluxes of heat associated with anomalous geostrophic currents are a major contributor dominating downstream of several topographic features reflecting the influence of eddies and frontal migrations a significant fraction of the variability of large scale sst anomalies is correlated with either enso or the sam each mode contributing roughly equally the relation between the heat budget terms and these climate modes is investigated showing in particular that anomalous ekman and air sea heat fluxes have a co operating effect with regional exceptions hence the large sst response associated with each mode it is further shown that enso or sam locked anomalous geostrophic currents generate substantial heat fluxes in all three basins with magnitude comparable with that of atmospheric forcings for enso and smaller for the sam except for limited areas enso locked forcings generate sst anomalies along the acc pathway and advection by mean flows is found to be a non negligible contribution to the heat budget exhibiting a wavenumber two zonal structure characteristic of the antarctic circumpolar wave by contrast sam related forcings are predominantly zonally uniform along the acc hence smaller zonal sst gradients and a lesser role of mean advection except in the southwest atlantic while modeled sst anomalies are significantly correlated with observations over most of the southern ocean the analysis of the data model discrepancies suggests that vertical ocean physics may play a significant role in the nonseasonal heat budget especially in some key regions for mode water formation

hydrocarbon genesis of jurassic coal measures in the turpan basin china abstract a typical case of coal derived oils in china i e the crude oils from the middle lower jurassic coal measure strata in the turpan basin is presented by means of oil source correlation it is confirmed that low maturity crude oil in the shengjinkou oil field is derived from the coal bearing qiketai formation of middle jurassic age a brackish lacustrine sediment mature crude oils in the qiketai oil field and in well taican 1 are sourced from the badaowan formation of lower jurassic age which contains coal seams as thick as 100 m results show that commercial accumulations of liquid crude oils can be generated from coals and coal measure strata containing high volatile coal of bituminous rank despite unfavourable types of source material the total hydrocarbon generating potential can be great due to the unusual abundance of organic matter

escape tectonics in the los angeles metropolitan region and implications for seismic risk recent damaging earthquakes in california including the 1971 san fernando1 1983 coalinga2 1987 whittier narrows3 and 1994 northridge4 events have drawn attention to thrust faults as both potentially hazardous seismic sources and as a mechanism for accommodating shortening in many regions of southern california consequently many geological studies5 6 have concluded that thrust faults in southern california pose the greatest seismic hazard and also account for most of the estimated 5 7 mm yr 1 of contraction across the greater los angeles metropolitan area7 8 indicated by global positioning system geodetic measurements9 our study demonstrates however that less than 50 of the geodetically observed contraction is accommodated on the principal thrust systems across the los angeles region we integrate the most recent geological geodetic and seismological data to assess the spatial distribution of strain across the los angeles metropolitan region we then demonstrate that a significant component of seismic moment release and shortening in this region is accommodated by east west crustal escape extrusion along known strike slip and oblique slip faults

earthquake relocations crustal rheology and active deformation in the central eastern alps n italy abstract a revised seismic catalogue 1994 2007 for the central eastern alps n italy is presented 396 earthquake relocations for local magnitudes in the 1 2 5 3 range are performed using a 3d crustal velocity structure and probabilistic locations the location procedure is validated by computing a set of 41 quarry shot solutions and all the results both about shots and seismic events are compared with those obtained using the routine location procedure results are shown for five contiguous seismotectonic domains as supported by geological and geophysical evidence e g fault systems crustal tomography focal mechanisms types earthquake hypocentres are mostly located in the upper crust 0 15 km of depth in good agreement with thermo rheological models about the brittle ductile transitions 8 9 km of depth and total crustal strengths 1 0 2 0 tn m 1 epicentres are clustered and or aligned along present day active geological structures the proposed seismotectonic model shows dominant compression along the giudicarie and belluno bassano montello thrusts with strain partitioning along the dominant right lateral strike slip faults of the schio vicenza domain the present day deformation of the southern alps and the internal alpine chain is compatible with adria indentation and the related crustal stress distribution

the petroleum generation potential and effective oil window of humic coals related to coal composition and age abstract a worldwide data set of more than 500 humic coals from the major coal forming geological periods has been used to analyse the evolution in the remaining hydrogen index hi and total quality index qi generation potentials with increasing thermal maturity and the effective oil window oil expulsion window all samples describe hi and qi bands that are broad at low maturities and that gradually narrow with increasing maturity the oil generation potential is completely exhausted at a vitrinite reflectance of 2 0 2 2 ro or tmax of 500 510 c the initial large variation in the generation potential is related to the original depositional conditions particularly the degree of marine influence and the formation of hydrogen enriched vitrinite as suggested by increased sulphur and hydrogen contents during initial thermal maturation the hi increases to a maximum value himax similarly qi increases to a maximum value qimax this increase in hi and qi is related to the formation of an additional generation potential in the coal structure the decline in qi with further maturation is indicating onset of initial oil expulsion which precedes efficient expulsion liquid petroleum generation from humic coals is thus a complex three phase process i onset of petroleum generation ii petroleum build up in the coal and iii initial oil expulsion followed by efficient oil expulsion corresponding to the effective oil window efficient oil expulsion is indicated by a decline in the bitumen index bi when plotted against vitrinite reflectance or tmax this means that in humic coals the vitrinite reflectance or tmax values at which onset of petroleum generation occurs cannot be used to establish the start of the effective oil window the start of the effective oil window occurs within the vitrinite reflectance range 0 85 1 05 ro or tmax range 440 455 c and the oil window extends to 1 5 2 0 ro or 470 510 c for general use an effective oil window is proposed to occur from 0 85 to 1 7 ro or from 440 to 490 c specific ranges for himax and the effective oil window can be defined for cenozoic jurassic permian and carboniferous coals cenozoic coals reach the highest himax values 220 370 mg hc g toc and for the most oil prone cenozoic coals the effective oil window may possibly range from 0 65 to 2 0 ro or 430 to 510 c in contrast the most oil prone jurassic permian and carboniferous coals reach the expulsion threshold at a vitrinite reflectance of 0 85 0 9 ro or tmax of 440 445 c

mg ca ratios in coralline algae record northwest atlantic temperature variations and north atlantic oscillation relationships climate variability in the north atlantic has been linked in part to the north atlantic oscillation nao the nao influences marine ecosystems in the northwestern atlantic and transport variability of the cold labrador current understanding historic patterns of nao variability requires long term and high resolution climate records that are not available from instrumental data here we present the first century scale proxy record of sea surface temperature sst variability from the newfoundland shelf a region from which other annual resolution shallow marine proxies are unavailable the 116 year record was obtained from three sites along the eastern newfoundland shelf using laser ablation inductively coupled mass spectrometry determined mg ca ratios in the crustose coralline alga clathromorphum compactum the alga is characterized by a high mg calcite skeleton exhibiting annual growth increments and a century scale lifespan results indicate positive correlations between interannual variations in mg ca ratios and both station based and gridded instrumental sst in addition the record shows high spatial correlations to sst across the newfoundland shelf and the gulf of st lawrence before 1950 the mg ca proxy record reveals significant departures from gridded temperature records while the newfoundland shelf is generally considered a region of negative correlations to the nao the algal time series as well as a recent modeling study suggest a variable negative relationship with the nao which is strongest after 1960 and before the mid 1930s

late cenozoic fold and thrust belt of the southern coast ranges and santa maria basin california 1 balanced cross sections across the santa maria basin and southern coast ranges of california show the pliocene to quaternary convergence to be a developing basement involved fold and thrust belt the fold and thrust belt is seismically active as evidenced by compressive earthquakes geodetic measurements of present shortening and folded quaternary deposits the pliocene and quaternary structure of the southern coast ranges is dominated by a series of large anticlinal structures that include the lompoc purisima trend the casmalia orcutt trend the point san luis anticline the santa lucia range anticlinorium and the la panza range anticlinorium the anticlinal trends are interpreted to be fault bend and fault propagation folds resulting from thrust ramps off thrust flat and a regional detachment at 11 14 km depth most of the thrust faults do not reach the surface blind thrust the southwestern range front of the san rafael mountains is interpreted to be the result of uplift above a ramp in the point san luis thrust the cross section across the southern coast ranges shows 26 8 km of shortening from the edge of the continental margin to the san andreas fault region wide shortening is interpreted to have begun between 2 0 and 4 0 ma which yields an average regional convergence rate of 6 7 13 4 mm yr the late pliocene and quaternary convergence across the onshore santa maria basin is interpreted to be 9 2 km and the average convergence rate is 2 3 4 6 mm yr compressive focal mechanisms and our structural analysis suggest that the ramp parts of the thrust system are the most likely sources for earthquakes the historic seismic record and length of the anticlinal trends suggest that the thrust ramps probably are capable of generating moderate to large earthquakes 5 0 m w 7 5 major thrust ramps underlie the city of san luis obispo and adjacent coastal towns cross section restoration reveals early formed hydrocarbon traps and accounts for the abundant hydrocarbon accumulations along the casmalia orcutt anticlinal trend and under the santa maria valley the cross sections and restorations also illustrate the importance of miocene and early pliocene normal faults to oil maturation and trapping concealed normal faults along the flanks of the major anticlinal trends and the subthrust area along the north side of the casmalia orcutt anticlinal trend form two relatively untested trap styles

simple kinetic models of petroleum formation part i oil and gas generation from kerogen modern basin analysis uses kinetic models to predict the extent of petroleum generation within potential source rocks the global kinetic model presented here assigns kinetic parameters based on gross depositional environment and stratigraphic age this is useful in areas of low geochemical knowledge including exploration frontiers five kerogen kinetic organofacies each characterized by a specific organic matter input and early diagenetic overprint can broadly be related to sedimentary facies age associations even using seismic sequence stratigraphy alone a aquatic marine siliceous or carbonate evaporite any age b aquatic marine siliciclastic any age c aquatic non marine lacustrine phanerozoic d e terrigenous non marine ever wet coastal mesozoic and younger and f terrigenous non marine coastal late palaeozoic and younger routine pyrolysis data allow partitioning of organic carbon in the immature source rock into four initial components oil oil generative gas generative and inert separate kinetic parameters for the oil and gas generative fractions allow computation of the evolving concentration and composition of the products it was assumed that the activation energy distributions for each fraction were normally distributed non linear regression of large combined laboratory and field data sets varying by up to 12 orders of magnitude in heating rate established optimum values for the required ten 5 2 kinetic parameter sets a emean e differences in kinetic parameters can be reconciled with known chemical properties although our knowledge base is still inadequate to construct kinetic models from first principles mean activation energies governing oil generation increase systematically in the order a f causing a corresponding increase in generation temperature at a reference heating rate 2 c ma 1 the oil generation window 10 90 oil generative kerogen degraded increases from ca 95 135 c to 145 175 c organofacies c has the tightest energy distribution and narrowest oil generation window the gas generation window ranges from ca 105 155 c to 175 220 c thermal stress results from a combination of temperature and time an order of magnitude increase decrease in heating rate elevates depresses reaction temperatures by ca 15 c heating rates in subsiding sedimentary basins can vary by two orders of magnitude dramatic differences in generation temperature can result if the heating rate and organofacies effects compound thus global oil and gas generation temperature thresholds constitute blunt instruments with which to screen the petroleum potential of sedimentary basins because unexpelled oil provides a potential feedstock for oil to gas cracking in the source rock quantitative models of petroleum generation become really useful only when coupled with models of oil gas cracking and expulsion for example the frequently observed association between gas provinces and coals cannot be explained solely by their generation behaviour

3 d velocity structure in southern haiti from local earthquake tomography we investigate 3 d local earthquake tomography for high quality travel time arrivals from aftershocks following the 2010 m7 0 haiti earthquake on the leog ne fault the data were recorded by 35 stations including 19 ocean bottom seismometers from which we selected 595 events to simultaneously invert for hypocenter location and 3 d vp and vs velocity structures in southern haiti we performed several resolution tests and concluded that clear features can be recovered to a depth of 15 km at 5 km depth we distinguish a broad low velocity zone in the vp and vs structure offshore near gonave island which correlate with layers of marine sediments results show a pronounced low velocity zone in the upper 5 km across the city of leog ne which is consistent with the sedimentary basin location from geologic map at 10 km depth we detect a low velocity anomaly offshore near the trois baies fault and a nw se directed low velocity zone onshore across petit go ve and jacmel which is consistent with a suspected fault from a previous study and that we refer to it in our study as the petit go ve jacmel fault these observations suggest that low velocity structures delineate fault structures and the sedimentary basins across the southern peninsula which is extremely useful for seismic hazard assessment in haiti

effective petroleum source rocks of the world stratigraphic distribution and controlling depositional factors six stratigraphic intervals representing one third of phanerozoic time contain petroleum source rocks that have provided more than 90 of the world s discovered original reserves of oil and gas in barrels of oil equivalent the six intervals are 1 silurian generated 9 of the world s reserves 2 upper devonian tournaisian 8 of reserves 3 pennsylvanian lower permian 8 of reserves 4 upper jurassic 25 of reserves 5 middle cretaceous 29 of reserves and 6 oligocene miocene 12 5 of reserves this uneven distribution of source rocks in time displays no obvious cyclicity and the factors that controlled the formation of source rocks vary from interval to interval maps that show facies structural forms and petroleum source rocks were prepared for this study analysis of the maps indicates that several primary factors controlled the areal distribution of source rocks their geochemical type and their effectiveness i e the amounts of discovered original conventionally recoverable reserves of oil and gas generated by these rocks these factors are geologic age paleolatitude of the depositional areas structural forms in which the deposition of source rocks occurred and the evolution of biota the maturation time of these source rocks demonstrates that the majority of discovered oil and gas is very young almost 70 of the world s original reserves of oil and gas has been generated since the coniacian and nearly 50 of the world s petrole m has been generated and trapped since the oligocene the term petroleum as used in this study includes oil gas condensate and gas but does not include bitumen and other solid and semisolid oil derivatives

evaluation of petroleum generation from resinites by hydrous pyrolysis hydrous pyrolysis experiments are useful in evaluating the composition yield and kinetics of liquid hydrocarbons generated from potential source rocks using this technique on a representative set of resinites revealed that fossil resin does not generate a light naphthenic crude oil gas chromatograms of liquid hydrocarbons generated by resinites are dominated by aromatic peaks and show no resemblance to commercially produced crude oils resinites may make minor contributions to conventionally sourced crude oils but their limited occurrence inhibits their potential as a prolific source of petroleum on a basinal scale data from the natural system and pyrolysis experiments also indicate that resinites do not generate liquid hydrocarbons at abnormally low levels of therm l maturity

geometry and earthquake potential of the shoreline fault central california abstract the shoreline fault is a vertical strike slip fault running along the coastline near san luis obispo california much is unknown about the shoreline fault including its slip rate and the details of its geometry here i study the geometry of the shoreline fault at seismogenic depth as well as the adjacent section of the offshore hosgri fault using seismicity relocations and earthquake focal mechanisms the optimal anisotropic dynamic clustering oadc algorithm ouillon et al 2008 is used to objectively identify the simplest planar fault geometry that fits all of the earthquakes to within their location uncertainty the oadc results show that the shoreline fault is a single continuous structure that connects to the hosgri fault discontinuities smaller than about 1 km may be undetected but would be too small to be barriers to earthquake rupture the hosgri fault dips steeply to the east while the shoreline fault is essentially vertical so the hosgri fault dips towards and under the shoreline fault as the two faults approach their intersection the focal mechanisms generally agree with pure right lateral strike slip on the oadc planes but suggest a non planar hosgri fault or another structure underlying the northern shoreline fault the shoreline fault most likely transfers strike slip motion between the hosgri fault and other faults of the pacific north america plate boundary system to the east a hypothetical earthquake rupturing the entire known length of the shoreline fault would have a moment magnitude of 6 4 6 8 a hypothetical earthquake rupturing the shoreline fault and the section of the hosgri fault north of the hosgri shoreline junction would have a moment magnitude of 7 2 7 5

decadal variability of hydrography in the upper northern north atlantic in 1948 1990 we investigate the variability of the north atlantic subarctic gyre in recent decades from time series of station temperature and salinity decadal variability stronger at the surface is identified which exhibits vertical coherence over a layer deeper than the late winter mixed layer in the northwestern atlantic it corresponds to the layer with a component of water from the arctic ocean or from the canadian arctic the spatial coherence of the signal is investigated an empirical orthogonal function decomposition of lagged time series indicates that a single pattern explains 70 of the variance in upper ocean salt content corresponding to a propagating signal from the west to the northeast in the subarctic gyre the most likely interpretation is that the salinity signal originates in the slope currents of the labrador sea and is diffused advected eastward of the grand banks over the near western atlantic in the northwestern atlantic temperature fluctuations are strongly correlated to salinity fluctuations and are aligned along the average t s characteristics this signal suggests large variations in the outflow of fresh cold water in the slope current and is strongly correlated with ice cover a basin scale atmospheric circulation of weakened westerlies at 55 n weaker northwesterlies west of greenland and weaker southerlies over the central and eastern north atlantic is associated with the high salinity and warm water phase of the first principal component this circulation pattern leads fluctuations in the northeast atlantic and lags those in the northwestern part of the basin the wind indices also suggest that the fluctuations of the fresh water outflow occur during intervals of anomalously northerly winds either east of greenland 1965 1968 1969 or off the canadian archipelago 1983 1984

winter to winter recurrence of sea surface temperature anomalies in the northern hemisphere the spatiotemporal characteristics of the winter to winter recurrence wwr of sea surface temperature anomalies ssta in the northern hemisphere nh are comprehensively studied through lag correlation analysis on this basis the relationships between the ssta wwr and the wwr of the atmospheric circu lation anomalies el nino southern oscillation enso and ssta interdecadal variability are also in vestigated results showthat the ssta wwr occurs over most parts of the north pacific and atlantic oceans but the spatiotemporaldistributionsofthesstawwraredistinctlydifferentinthesetwooceans analysesindicate that the spatiotemporal distribution of the ssta wwr in the north atlantic ocean is consistent with the spatial distribution of the seasonal cycle of its mixed layer depth mld whereas that in the north pacific ocean particularly the recurrence timing cannot be fully explained by the change in the mld between winterandsummerin someregions inaddition theatmospheric circulationanomaliesalsoexhibitthewwr at the mid high latitude of the nh which is mainly located in eastern asia the central north pacific and the north atlantic the sea level pressure anomalies slpa in the central north pacific are essential for the occurrenceofthesstawwrinthisregion moreover thestrongestpositivecorrelationoccurswhentheslpa lead ssta in the central northpacific by 1 month whichsuggeststhat the atmospheric forcingon the ocean may play a dominant role in this region therefore the reemergence mechanism is not the only process influ encing the ssta wwr and the wwr of the atmospheric circulation anomalies may be one of the causes of the ssta wwr in the central north pacific finally the occurrence of the ssta wwr in the nh is closely related to ssta interdecadal variability in the nh but it is linearly independent of enso

seismicity of south central coastal california october 1987 through january 1997 earthquakes recorded along south central coastal california from october 1987 through january 1997 by the pacific gas and electric company9s 20 station central coast seismic network and the u s geological survey9s northern and southern california networks are used to study their relation to previous seismicity mapped quaternary faults and regional tectonic features we developed p and s wave velocity models station corrections and duration magnitude calibrations to process 1184 reliable earthquake locations and 212 well constrained focal mechanisms seismicity generally coincides with mapped quaternary faults and areas of tectonic uplift including the southern offshore santa maria basin and areas to the west and the uplifted blocks within the los osos tectonic domain comparison of our data to previous microearthquake locations 1969 1987 and larger m 5 historical earthquakes shows that these patterns have been persistent seismically quiescent areas have few or no mapped quaternary faults and typically are structural lows the base of the seismogenic zone is about 12 km in depth above the relic oceanic crust microearthquake locations and strike slip focal mechanisms document the strike slip nature of the hosgri fault zone and its step over to the san simeon fault along the western boundary of the los osos domain uplifting blocks within the los osos domain are most seismically active toward their western ends along the hosgri fault zone and they exhibit reverse and oblique faulting consistent with block uplift and interaction with the hosgri fault zone the observed patterns and character of microseismicity and macroseismicity clearly show transpressional deformation associated with the hosgri fault zone overprinted by rotation and westward migration of the western transverse ranges within this tectonic setting clockwise rotation of the western transverse ranges causes internal deformation of the los osos domain and westward migration of the ranges appears to deflect the hosgri fault zone westward and causes east west directed crustal shortening in the southern offshore santa maria basin

an intimate coupling of ocean atmospheric interaction over the extratropical north atlantic and pacific the inter basin teleconnection between the north atlantic and the north pacific ocean atmosphere interaction is studied using a coupled ocean atmosphere general circulation model in the model an idealized oceanic temperature anomaly is initiated over the kuroshio and the gulf stream extension region to track the coupled evolution of ocean and atmosphere interaction respectively the experiments explicitly demonstrate that both the north pacific and the north atlantic ocean atmosphere interactions are intimately coupled through an inter basin atmospheric teleconnection this fast inter basin communication can transmit oceanic variability between the north atlantic and the north pacific through local ocean to atmosphere feedbacks the leading mode of the extratropical atmospheric internal variability plays a dominant role in shaping the hemispheric scale response forced by oceanic variability over the north atlantic and pacific modeling results also suggest that a century two centuries long observations are necessary for the detection of pacific response to atlantic forcings atlantic response to pacific forcing

seismotectonics and fault structure of the california central coast abstract i present and interpret new earthquake relocations and focal mechanisms for the california central coast the relocations improve upon catalog locations by using 3d seismic velocity models to account for lateral variations in structure and by using relative arrival times from waveform cross correlation and double difference methods to image seismicity features more sharply focal mechanisms are computed using ray tracing in the 3d velocity models seismicity alignments on the hosgri fault confirm that it is vertical down to at least 12 km depth and the focal mechanisms are consistent with right lateral strike slip motion on a vertical fault a prominent newly observed feature is an 25 km long linear trend of seismicity running just offshore and parallel to the coastline in the region of point buchon informally named the shoreline fault this seismicity trend is accompanied by a linear magnetic anomaly and both the seismicity and the magnetic anomaly end where they obliquely meet the hosgri fault focal mechanisms indicate that the shoreline fault is a vertical strike slip fault several seismicity lineations with vertical strike slip mechanisms are observed in estero bay events greater than about 10 km depth in estero bay however exhibit reverse faulting mechanisms perhaps reflecting slip at the top of the remnant subducted slab strike slip mechanisms are observed offshore along the hosgri san simeon fault system and onshore along the west huasna and rinconada faults while reverse mechanisms are generally confined to the region between these two systems this suggests a model in which the reverse faulting is primarily due to restraining left transfer of right lateral slip

reemergence areas of winter sea surface temperature anomalies in the world s oceans 1 using datasets of sea surface temperature sst surface heat flux upper ocean thermal data and climatological temperature and salinity profiles we try to detect reemergence areas of winter sst anomalies in the world s oceans and describe characteristics of these areas in terms of mixed layer depth mld annual mean heat flux and properties of waters formed in winter mixed layer eventually seven reemergence areas are found four in the northern hemisphere and three in the southern hemisphere all areas have a large seasonal variation of mld and are the regions where annual mean heat fluxes are relatively small except for two regions in the northern hemisphere in the viewpoint of water properties it is found that these areas correspond to the mode water formation regions subtropical mode waters of the indian ocean south pacific south atlantic north pacific and north atlantic and north pacific central and north atlantic subpolar mode waters

on the reemergence of north atlantic sst anomalies abstract the reemergence mechanism whereby temperature anomalies extending over the deep winter mixed layer are stored beneath the surface in summer and are reentrained into the mixed layer when it deepens again in the following autumn and winter is studied in the north atlantic using approximately 40 years of surface and subsurface data reemergence is found to be robust in the sargasso sea and the northeast atlantic regions where i the mixed layer is much deeper in winter than in summer ii currents are relatively weak and iii temperature anomalies are coherent over broad areas the two leading empirical orthogonal functions of north atlantic sst anomalies also exhibit strong reemergence signatures a novel application of empirical orthogonal function analysis to temperature anomalies in the time depth plane which also incorporates information from all grid points is shown to be an efficient and useful approach for detecting reemergence without dependence on specific spatial patterns or prio

origin and structure of the fossil resin from an indonesian miocene coal abstract the structure of a fossil resin from miocene coal outcrops of the bukit asam region sumatra has been studied the fossil material has been formed from sesqui and tri terpenes from trees of the dipterocarp family the original terpenes have lost virtually all oxygen containing functions and the resulting mono and di olefins have polymerized to a mainly non crosslinked resin whose components have molecular weights of up to 300 000

hydrothermal petroleums from yellowstone national park wyoming u s a abstract in yellowstone national park oil is actively discharging with thermal waters at several widely separated thermal areas samples from two locations were studied petroleum from calcite springs occurs as vapor condensates in steam vents detailed geochemical analyses show a complex origin for the petroleum fluid deeply buried hydrothermally altered sedimentary rocks are believed to have contributed a high temperature pyrolysate consisting largely of polynuclear aromatic hydrocarbons and heterocyclic compounds shallow sedimentary rocks which are also hydrothermally altered have contributed large amounts of aromatic and polar compounds as well as minor amounts of hydrocarbons the permian phosphoria formation is suggested as a likely source rock for the bulk of the oils autochthonous pyrolysates and lipids from thermally altered surface and near surface bacterial and land plant debris have also been introduced to the vents the latter may have been introduced by downward percolating meteoric water the oil from rainbow springs is a highly paraffinic low s crude oil depleted in light hydrocarbons unlike the calcite springs samples the oil from rainbow springs is believed to have originated from a single sedimentary source rock with little or no hydrocarbon contributions from surface biota the oil contains a unique molecular marker assemblage that suggests both gymnosperm and angiosperm input and places the age of the source unit in the tertiary consideration of the local stratigraphy and water temperatures limits the probable source zone to the eocene aycross formation an intra volcanic lacustrine mudstone calculation of deep water temperatures indicates that this unit is exposed to thermal waters in an extensive near surface aquifer such conditions are consistent with the widespread surface manifestations and biomarker kinetic models consideration of the petroleum chemistry and regional hydrodynamics indicates that the yellowstone park oils did not migrate into the park from distant sources the chemical data are also inconsistent with the oils being generated and trapped prior to tertiary volcanism at both calcite springs and rainbow springs oil generation appears to be contemporaneous and is attributed to thermal alteration of relatively shallow sedimentary rocks by hydrothermal fluids

year to year reoutcropping of eighteen degree water in an eddy resolving ocean simulation abstractwinter outcropping of the eighteen degree water edw and its subsequent dispersion are studied using a eddy resolving simulation of the family of linked atlantic modeling experiments flame outcropped edw columns in the model simulations are detected in each winter from 1990 to 1999 and particles are deployed in the center of each outcropped edw column subsequently the trajectories of these particles are calculated for the following 5 yr the particles slowly spread away from the outcropping region into the nonoutcropping subducted edw region south of 30 n and eventually to the non edw region in the greater subtropical gyre approximately 30 of the particles are found in non edw waters 1 yr after deployment after 5 yr only 25 of the particles are found within edw the reoutcropping time is defined as the number of years between when a particle is originally deployed in an outcropping edw column and when that particle is next found in an outcropping edw column of the particles 66 ar

influence of rock particle size on the artificial thermal evolution of kerogen a petrographic and geochemical study abstract two series of samples grain series gs and block series bs with different particle size between 0 5 1 0 mm and 1 5 1 5 5 0 cm and rock geometry irregular and prismatic respectively were obtained from an oil shale with type ii kerogen from cantabria northern spain both series were pyrolyzed at different temperatures between 50 and 500 c by the open medium pyrolysis system petrological and geochemical analyses were carried out to determine the organic transformation level to characterize the resulting products and to establish a relation of maturation between the two series results show that the main processes of organic diagenesis occurred at a temperature interval ranging from 250 to 450 c in both series however differences in evolution parameters show that the diagenetic processes do not occur in the same way in both series as they depend on the physico morphological characteristics of the rock that is being pyrolyzed this is reflected in the greater level of oil production and expulsion during the pyrolysis process that is more important in bs than in gs expulsion seems to be favoured by the fissure system developed during the thermal evolution in bs which does not occur in samples with smaller particle size at the same time in bs a greater retention of some polar components asphaltenes leading to a differential impregnation of vitrinites is produced this explains the differences in reflectance found between both series after the primary cracking the results of this study confirm and supplement previous work about the importance of confinement in pyrolysis experiments aiming to reproduce sedimentary organic diagenesis in addition to qualitative and quantitative variations in kerogen degradation products the present study conducted on rock samples shows that the confinement also enhances oil expulsion through cracks and fissures developed in the rock in the course of heating although these results are probably not directly applicable to natural series they help to interpret the origin of discrepancies between evolution parameters which appear to be primarily related to confinement

summertime evolution of decadal sea surface temperature anomalies in the midlatitude north pacific abstract to clarify the summertime evolution of decadal sea surface temperature sst anomalies and related physical processes in the midlatitudes of the north pacific numerical solutions of a three dimensional bulk mixed layer model are analyzed focusing on the contribution of the net shortwave radiative forcing at the sea surface a quantitative heat budget analysis for the ocean mixed layer relating to late 1980s decadal sst change reveals that the decadal sst anomalies decay from late spring to early summer over the entire midlatitudes of the north pacific this quasi seasonal decay of the decadal sst anomalies is controlled by an anomalous local thermal damping i e anomalous surface heat fluxes from midsummer to early autumn the anomalous net shortwave radiation flux associated with a meridional shift of the storm track acts to induce strong seasonal damping of the decadal sst anomaly in the northern kuroshio oyashio extension region in contrast in the north of the subtropical frontal region

southern ocean mixed layer depth from argo float profiles 1 argo float profiles of temperature salinity and pressure are used to derive the mixed layer depth mld in the southern ocean mld is determined from individual profiles using both potential density and potential temperature criteria and a monthly climatology is derived from individual mlds using an objective mapping method quantitative data are available in the auxiliary material the spatial structures of mlds are similar in each month with deep mixed layers within and just north of the antarctic circumpolar current acc in the pacific and indian oceans the deepest mixed layers are found from june to october and are located just north of the acc where antarctic intermediate water aaiw and subantarctic mode water samw are formed examination of individual mlds indicates that deep mixed layers mld 400 m from both the density and temperature criteria are concentrated in a narrow surface density band which is within the density range of samw the surface salinity for these deep mixed layers associated with the samw formation are slightly fresher compared to historical estimates differences in air sea heat exchanges wind stress and wind stress curl in the pacific and indian oceans suggest that the mode water formation in each ocean basin may be preconditioned by different processes wind mixing and ekman transport of cold water from the south may assist the samw formation in the indian ocean in the eastern pacific the formation of mode water is potentially preconditioned by the relative strong cooling and weak stratification from upwelling

a model of the earthquake cycle along the san andreas fault system for the past 1000 years 1 we simulate 1000 years of the earthquake cycle along the san andreas fault system by convolving best estimates of interseismic and coseismic slip with the green s function for a point dislocation in an elastic plate overlying a viscoelastic half space interseismic slip rate is based on long term geological estimates while fault locking depths are derived from horizontal gps measurements coseismic and postseismic deformation is modeled using 70 earthquake ruptures compiled from both historical data and paleoseismic data this time dependent velocity model is compared with 290 present day geodetic velocity vectors to place bounds on elastic plate thickness and viscosity of the underlying substrate best fit models rms residual of 2 46 mm yr require an elastic plate thickness greater than 60 km and a substrate viscosity between 2 1018 and 5 1019 pa s these results highlight the need for vertical velocity measurements developed over long time spans 20 years our numerical models are also used to investigate the 1000 year evolution of coulomb stress stress is largely independent of assumed rheology but is very sensitive to the slip history on each fault segment as expected present day coulomb stress is high along the entire southern san andreas because there have been no major earthquakes over the past 150 300 years animations s1 and s2 of the time evolution of vector displacement and coulomb stress are available as auxiliary material

a mechanism for the recurrence of wintertime midlatitude sst anomalies abstract in the early 1970s namias and born speculated that ocean temperature anomalies created over the deep mixed layer in winter could be preserved in the summer thermocline and reappear at the surface in the following fall or winter this hypothesis is examined using upper ocean temperature observations and simulations with a mixed layer model the data were collected at six ocean weather stations in the north atlantic and north pacific concurrent and lead lag correlations are used to investigate temperature variations associated with the seasonal cycle in both the observations and the model simulations concurrent correlations between the surface and subsurface temperature anomalies in both the data and the model indicate that the penetration of temperature anomalies into the ocean is closely tied to the seasonal cycle in mixed layer depth high correlations extend to relatively deep shallow depths in winter summer lead lag correlations in both the data and the model at some of the stations

three dimensional compressional wavespeed model earthquake relocations and focal mechanisms for the parkfield california region we present a new three dimensional 3d compressional wavespeed v p model for the parkfield region taking advantage of the recent seismicity associated with the 2003 san simeon and 2004 parkfield earthquake sequences to provide increased model resolution compared to the work of eberhart phillips and michael 1993 epm93 taking the epm93 3d model as our starting model we invert the arrival time data from about 2100 earthquakes and 250 shots recorded on both permanent network and temporary stations in a region 130 km northeast southwest by 120 km northwest southeast we include catalog picks and cross correlation and catalog differential times in the inversion using the double difference tomography method of zhang and thurber 2003 the principal v p features reported by epm93 and michelini and mcevilly 1991 are recovered but with locally improved resolution along the san andreas fault saf and near the active source profiles we image the previously identified strong wavespeed contrast faster on the southwest side across most of the length of the saf and we also improve the image of a high v p body on the northeast side of the fault reported by epm93 this narrow body is at about 5 to 12 km depth and extends approximately from the locked section of the saf to the town of parkfield the footwall of the thrust fault responsible for the 1983 coalinga earthquake is imaged as a northeast dipping high wavespeed body in between relatively low wavespeeds 5 km sec extend to as much as 10 km depth we use this model to derive absolute locations for about 16 000 earthquakes from 1966 to 2005 and high precision double difference locations for 9 000 earthquakes from 1984 to 2005 and also to determine focal mechanisms for 446 earthquakes these earthquake locations and mechanisms show that the seismogenic fault is a simple planar structure the aftershock sequence of the 2004 mainshock concentrates into the same structures defined by the pre 2004 seismicity confirming earlier observations waldhauser et al 2004 that the seismicity pattern at parkfield is long lived and persists through multiple cycles of mainshocks online material 3d v p model and earthquake relocations

determining the petroleum generating potential of coal using organic geochemistry and organic petrology abstract the ardjuna basin of northwest java is typical of many tertiary basins in that it contains high wax crude oil pyrolysis gas chromatography revealed that potential precursors of long chain waxy paraffins are present in coals of the talang akar formation and are most abundant in those that are rich in matrix liptinite conversely it was not possible to estimate waxy oil generating potential using rock eval because pyrolysates from talang akar coal are mainly comprised of naphthenic and aromatic compounds these being derived from resinite and fluorescing vitrinite because of a controlling influence by the abundance of these macerals changes in hydrogen index could not be used to assess maturity resinite and related macerals might play an especially important role in petroleum expulsion as evidenced by their high genetic potential and hence inherent capability of saturating the source rock pore system it is speculated that their maturation products while not constituting typical crude oil might pervade the coal fabric deactivate adsorptive sites and hence facilitate the expulsion of waxy oil that is generated from matrix liptinite

seismicity rate changes along the central california coast due to stress changes from the 2003 m 6 5 san simeon and 2004 m 6 0 parkfield earthquakes abstract we investigated the relationship between seismicity rate changes and modeled coulomb static stress changes from the 2003 m 6 5 san simeon and the 2004 m 6 0 parkfield earthquakes in central california coulomb stress modeling indicates that the san simeon mainshock loaded parts of the rinconada hosgri and san andreas strike slip faults along with the reverse faults of the southern los osos domain all of these loaded faults except for the san andreas experienced a seismicity rate increase at the time of the san simeon mainshock the parkfield earthquake occurred 9 months later on the loaded portion of the san andreas fault the parkfield earthquake unloaded the hosgri fault and the reverse faults of the southern los osos domain which both experienced seismicity rate decreases at the time of the parkfield event although the decreases may be related to the decay of san simeon triggered seismicity coulomb stress unloading from the parkfield earthquake appears to have altered the aftershock decay rate of the southern cluster of san simeon aftershocks which is deficient compared to the expected number of aftershocks from the omori decay parameters based on the pre parkfield aftershocks dynamic stress changes cannot explain the deficiency of aftershocks providing evidence that static stress changes affect earthquake occurrence however a burst of seismicity following the parkfield earthquake at ragged point where the static stress was decreased provides evidence for dynamic stress triggering it therefore appears that both coulomb static stress changes and dynamic stress changes affect the seismicity rate

effects of thermal maturation on stable organic carbon isotopes as determined by hydrous pyrolysis of woodford shale acquiring crude oils that have been expelled from the same rock unit at different levels of thermal maturation is currently not feasible in the natural system this prevents direct correlation of compositional changes between the organic matter retained in a source rock and its expelled crude oil at different levels of thermal maturation alleviation of this deficiency in studying the natural system requires the use of laboratory experiments natural generation of petroleum from amorphous type ii kerogen in the woodford shale may be simulated by hydrous pyrolysis which involves heating crushed rock in contact with water at subcritical temperatures 374 c four distinct stages of petroleum generation are observed from this type of pyrolysis 1 pre oil generation 2 incipient oil generation 3 primary oil generation and 4 post oil generation the effects of thermal maturation on the 13c values of kerogen bitumen and expelled oil like pyrolysate from the woodford shale have been studied through these four stages of petroleum generation similar to the natural system the kerogens isolated from the pyrolyzed rock showed no significant change in 13c this suggests that the 13c value of kerogens may be useful in kerogen typing and oil to source rock correlations 13c values of bitumens extracted from the pyrolyzed rock showed an initial decrease during the incipient oil generation stage followed by depletion during the primary and post oil generation stages this reversal is not favorable for geochemical correlation or maturity evaluation saturated and polar components of the bitumen show the greatest 13c variations with increasing thermal maturation the difference between the 13c of these two components gives a unidirectional trend that serves as a general indicator of thermal maturation and is referred to as the bitumen isotope index bii 13c values of the expelled pyrolysates show a unidirectional increase with increasing thermal maturation the constancy and similarity of 13c values of the aromatic components in the expelled pyrolysates and bitumens with increasing thermal maturation encourages their use in oil to oil and oil to source rock correlations isotopic type curves for expelled pyrolysates indicate that they may be useful in oil to oil correlations but have a limited use in oil to source rock correlations

seasonal evolutions of atmospheric response to decadal sst anomalies in the north pacific subarctic frontal zone observations and a coupled model simulation abstractpotential impacts of pronounced decadal scale variations in the north pacific sea surface temperature sst that tend to be confined to the subarctic frontal zone safz upon seasonally varying atmospheric states are investigated by using 48 yr observational data and a 120 yr simulation with an ocean atmosphere coupled general circulation model cgcm sst fields based on in situ observations and the ocean component of the cgcm have horizontal resolutions of 2 0 and 0 5 respectively which can reasonably resolve frontal sst gradient across the safz both the observations and cgcm simulation provide a consistent picture between sst anomalies in the safz yielded by its decadal scale meridional displacement and their association with atmospheric anomalies correlated with sst anomalies persistent in the safz from fall to winter a coherent decadal scale signal in the wintertime atmospheric circulation over the north pacific starts emerging in november and develops into an equivalent barotropic an

present tectonic motion across the coast ranges and san andreas fault system in central california geodetic results from very long baseline interferometry vlbi satellite laser ranging slr and the global positioning system gps are used to estimate angular velocities between the sierran microplate pacific plate and north american plate the sierra pacific pole of rotation lies nearer to the san andreas fault than does the pacific north america pole of rotation and leads to different tectonic implications than if the latter is used the angular velocities show that the san andreas fault system and central california coast ranges accommodate motion of 39 2 mm yr mainly by strike slip faulting all confidence limits following signs in this paper are 95 confidence limits fault normal motion is small is mainly convergent at rates up to 3 3 1 0 mm yr and varies along the coast but is divergent at 2 6 1 2 mm yr across san pablo bay and associated topographic lows across which the sierran and central valley watershed drains to the pacific ocean the mountain ranges tend to be larger where the fault normal convergence rates are larger the low convergence rate 0 5 1 8 mm yr normal to the san andreas fault in the carrizo plain differs sharply from that previously inferred 8 2 1 2 mm yr and 4 9 1 6 mm yr by feigl et al 1993 the difference is due to differences between their and our elastic strain accumulation models and between how their and our pacific plate reference frames are defined the ranges in most places require a minimum of 4 2 1 m y of fault normal convergence at the present rate to attain their present cross sectional area if erosion is neglected more if it is not the amount of convergence previously estimated from a balanced cross section across the diablo range in central california requires 10 8 3 m y of convergence at the present rate the former is consistent with widely held views about the onset of the coast range orogeny but the latter is not both are consistent however with the recent plate reconstructions by s cande j stock and colleagues which indicate that pacific plate motion relative to north america changed to a more convergent direction 20 25 clockwise of its prior direction at ca 8 to 6 ma and not at 3 5 ma as had been previously inferred the inferred change in direction of plate motion is large compared with the present angle of convergence across the straight and narrow segment of the san andreas fault of 0 7 4 7 from which we infer that the sierran microplate changed motion relative to north america at the same time ca 8 to 6 ma as did the pacific plate we further infer that the motion accommodated across the great basin must also have changed at the same time we also examine the hypothesis that stable sliding occurs along the san andreas fault and other northwest striking strike slip faults in central california where the fault normal convergence rate is low or negative and that these faults are unstable where the fault normal convergence rate is high such a relationship appears to hold in general but fails in detail in particular there are substantial sections of fault with small inferred rates of fault normal convergence across which the san andreas fault is locked moreover the creeping section of the san andreas fault i e the section between parkfield and the calaveras junction is the locus of greater fault normal convergence 3 2 1 4 mm yr than is the locked part of the fault 0 5 1 8 mm yr south of parkfield thus this hypothesis is at best a partial explanation for the observed distribution of locked and nonlocked sections of the fault

complex faulting associated with the 22 december 2003 mw 6 5 san simeon california earthquake aftershocks and postseismic surface deformation we use data from two seismic networks and satellite interferometric synthetic aperture radar insar imagery to characterize the 22 december 2003 m w 6 5 san simeon earthquake sequence absolute locations for the mainshock and nearly 10 000 aftershocks were determined using a new three dimensional 3d seismic velocity model relative locations were obtained using double difference the mainshock location found using the 3d velocity model is 35 704 n 121 096 w at a depth of 9 7 0 7 km the aftershocks concentrate at the northwest and southeast parts of the aftershock zone between the mapped traces of the oceanic and nacimiento fault zones the northwest end of the mainshock rupture as defined by the aftershocks projects from the mainshock hypocenter to the surface a few kilometers west of the mapped trace of the oceanic fault near the santa lucia range front and the 5 mm postseismic insar imagery contour the oceanic fault in this area as mapped by hall 1991 is therefore probably a second order synthetic thrust or reverse fault that splays upward from the main seismogenic fault at depth the southeast end of the rupture projects closer to the mapped oceanic fault trace suggesting much of the slip was along this fault or at a minimum is accommodating much of the postseismic deformation insar imagery shows 72 mm of postseismic uplift in the vicinity of maximum coseismic slip in the central section of the rupture and 48 and 45 mm at the northwest and southeast end of the aftershock zone respectively from these observations we model a 30 km long northwest trending northeast dipping mainshock rupture surface called the mainthrust which is likely the oceanic fault at depth a 10 km long southwest dipping backthrust parallel to the mainthrust near the hypocenter several smaller southwest dipping structures in the southeast and perhaps additional northeast dipping or subvertical structures southeast of the mainshock plane discontinuous backthrust features opposite the mainthrust in the southeast part of the aftershock zone may offset the relic nacimiento fault zone at depth the insar data image surface deformation associated with both aseismic slip and aftershock production on the mainthrust and the backthrusts at the northwest and southeast ends of the aftershock zone the well defined mainthrust at the latitude of the epicenter and antithetic backthrust illuminated by the aftershock zone indicate uplift of the santa lucia range as a popup block aftershocks in the southeast part of the zone also indicate a popup block but it is less well defined the absence of backthrust features in the central part of the zone suggests range front uplift by fault propagation folding or backthrusts in the central part were not activated during the mainshock

oceanic transport of fossil dammar resin the chemistry of coastal resinites from south australia abstract fragments of resin and fossilised resin resinites occasionally wash ashore along the southern australian coast chemical and isotopic analyses were carried out on a suite of coastal and reference resinites to determine the likelihood of a local as opposed to a distant origin all of the coastal resinites were found to contain a polymer based on the sesquiterpenoid cadinene skeleton and were markedly different to the diterpenoid resinites found in local victorian coals the coastal resinites closely resemble both fossil and recent dammar resin a material associated primarily with the tropical angiosperm hardwoods of southeast asia and one which has no known australian source minor variations in the composition of our resinite samples are attributed to differences in their thermal history these findings confirm the viability of long distance oceanic transport not only for the resinites but also for the waxy bitumens that strand along the same coastline analytical data on the coastal resinites also help to clarify the role of dammar resin in generating bicadinanes a class of source and age specific triterpanes found commonly in the cainozoic oils and sediments of southeast asia

seasonality of decadal sea surface temperature anomalies in the northwestern pacific abstract the seasonality of the decadal sea surface temperature sst anomalies and the related physical processes in the northwestern pacific were investigated using a three dimensional bulk mixed layer model in the kuroshio oyashio extension koe region the strongest decadal sst anomaly was observed during december february while that of the central north pacific occurred during february april from an examination of the seasonal heat budget of the ocean mixed layer it was revealed that the seasonal scale enhancement of the decadal sst anomaly in the koe region was controlled by horizontal ekman temperature transport in early winter and by vertical entrainment in autumn the temperature transport by the geostrophic current made only a slight contribution to the seasonal variation of the decadal sst anomaly despite controlling the upper ocean thermal conditions on decadal time scales through the slow rossby wave adjustment to the wind stress curl when averaging over the entire koe region the cont

slicing up the san francisco bay area block kinematics and fault slip rates from gps derived surface velocities received 26 october 2004 revised 11 february 2005 accepted 10 march 2005 published 16 june 2005 i observations of surface deformation allow us to determine the kinematics of faults in the san francisco bay area we present the bay area velocity unification bavu bay view a compilation of over 200 horizontal surface velocities computed from campaign style and continuous global positioning system gps observations from 1993 to 2003 we interpret this interseismic velocity field using a three dimensional block model to determine the relative contributions of block motion elastic strain accumulation and shallow aseismic creep the total relative motion between the pacific plate and the rigid sierra nevada great valley sngv microplate is 37 9 0 6 mm yr 1 directed toward n30 4 w 0 8 at san francisco 2 fault slip rates from our preferred model are typically within the error bounds of geologic estimates but provide a better fit to geodetic data notable right lateral slip rates in mm yr 1 san gregorio fault 2 4 1 0 west napa fault 4 0 3 0 zone of faulting along the eastern margin of the coast range 5 4 1 0 and mount diablo thrust 3 9 1 0 of reverse slip and 4 0 0 2 of right lateral strike slip slip on the northern calaveras is partitioned between both the west napa and concord green valley fault systems the total convergence across the bay area is negligible poles of rotation for bay area blocks progress systematically from the north america pacific to north america sngv poles the resulting present day relative motion cannot explain the strike of most bay area faults but fault strike does loosely correlate with inferred plate motions at the time each fault initiated

occurrence and palaeoenvironmental significance of aromatic hydrocarbon biomarkers in oligocene sediments from the mallik 5l 38 gas hydrate production research well canada abstract the aromatic hydrocarbon biomarker distributions of thirty oligocene sediment samples with different lithology lignite clay and sand from the japex jnoc gsc et al mallik 5l 38 gas hydrate production research well canada were analyzed using gas chromatography mass spectrometry gc ms the compositions vary with lithology indicating a change in palaeoenvironmental conditions at the time of deposition aromatic diterpenoids of the abietane type are more abundant in the lignite samples than in the clay samples and represent a gymnosperm e g conifer dominated palaeovegetation in contrast in the clay samples aromatic triterpenoids are generally preserved as major constituents indicating angiosperm dominated vegetation the sand samples contain only minor amounts of aromatic terpenoids but show a preference for diterpenoid gymnosperm markers to recognise gymnosperm versus angiosperm dominated palaeoenvironments a new ratio termed the angiosperm gymnosperm aromatic ratio agar has been developed thus the terpenoid distribution in the deltaic sediments provides information on the compositional changes in the plant community at the mallik site lignites and the hinterland clays over time concomitantly the changing dominance in the plant communities allows an insight into varying climatic conditions during the late oligocene in the area additionally the aromatic biomarker composition has been used to assess the level of thermal maturity of the organic matter in the mallik samples and indicates a prevailing immature character