胜利油田车镇凹陷沙河街组二、三段沉积相

车镇凹陷古近系沙河街组三段上亚段-二段下亚段是较为典型的深断陷型三级层序.层序的发育主要受控于幕式断陷作用,可进一步划分出低位体系域、湖侵体系域和高位体系域.通过岩心观察、薄片镜下鉴定、粒度分析、古生物及遗迹化石分析,并综合利用测井曲线和地震相特征,认为该时期主要发育有扇三角洲、三角洲、近岸水下扇、湖底扇、滨浅湖滩坝等骨架砂体相,以及滨浅湖、半深湖-深湖等沉积相及其亚相.综合考虑物源特征、沉积环境、沉积体系平面展布以及生、储、盖组合关系,认为有利的沉积相带主要是三角洲、扇三角洲前缘、湖底扇、近岸水下扇的中扇和外扇以及滨浅湖中发育的滩坝和砂坝.     

Outlier detection algorithms and their performance in GOCE gravity field processing

The satellite missions CHAMP, GRACE, and GOCE mark the beginning of a new era in gravity field determination and modeling. They provide unique models of the global stationary gravity field and its variation in time. Due to inevitable measurement errors, sophisticated pre-processing steps have to be applied before further use of the satellite measurements. In the framework of the GOCE mission, this includes outlier detection, absolute calibration and validation of the SGG (satellite gravity gradiometry) measurements, and removal of temporal effects. In general, outliers are defined as observations that appear to be inconsistent with the remainder of the data set. One goal is to evaluate the effect of additive, innovative and bulk outliers on the estimates of the spherical harmonic coefficients. It can be shown that even a small number of undetected outliers (<0.2 of all data points) can have an adverse effect on the coefficient estimates. Consequently, concepts for the identification and removal of outliers have to be developed. Novel outlier detection algorithms are derived and statistical methods are presented that may be used for this purpose. The methods aim at high outlier identification rates as well as small failure rates. A combined algorithm, based on wavelets and a statistical method, shows best performance with an identification rate of about 99%. To further reduce the influence of undetected outliers, an outlier detection algorithm is implemented inside the gravity field solver (the Quick-Look Gravity Field Analysis tool was used). This results in spherical harmonic coefficient estimates that are of similar quality to those obtained without outliers in the input data.     

Isothermal annealing of partially metamict zircon: evidence for a three-stage recovery process

 Raman spectroscopy and the powder diffraction technique have been used to monitor the recovery process of two partially metamict zircons (2.6 and 4.8 × 10¹⁸ α-decays g⁻¹) from Sri Lanka during a series of isothermal annealing experiments in the temperature range from 870 to 1622 K. These experiments show for the first time that structural recovery in partially metamict zircon proceeds via three distinct recovery stages, each of which occurs within a distinct time-temperature regime. Whereas the first two stages have previously been recognized (recovery of damaged crystalline remnants and epitaxial recrystallization), the third stage has not yet been identified as a single activated process. It is suggested that anisotropic defect annealing during the first stage at low temperatures, where the structure recovers preferentially along the a(b) plane, produces a geometrical situation where large structural rearrangements are necessary to remove the remaining defects inside the crystalline material. This situation is approximately reached when the amorphous domains start to recrystallize. The reason for anisotropic annealing can be found in a different connectivity between polyhedral linkages in both directions of the zircon lattice. High apparent activation energies, in the range of 6.4 to 7.9 eV, were determined for the third recovery stage from the Raman data, which are interpreted to reflect large structural rearrangements (i.e. polyhedral tilting) associated with the final recovery of the c axis. This explains the occurrence of a distinct recrystallization stage without defect annealing. Finally, it should be mentioned that the first recovery stage is not necessarily expected to occur in less damaged zircon crystals (<∼2 × 10¹⁸ α-decays g⁻¹), since less stable defects along the basal plane might have already been self-annealed during radiation damage accumulation under ambient temperatures. Received: 6 September 2001 / Accepted: 25 February 2002     

Structure of the earth's crust in Jordan from potential field data

Gravity and magnetic data were collected and used to study the crustal structure of Jordan. Three new geophysical maps of Jordan were created: a Moho discontinuity map, a crystalline basement surface map, and a map showing the lowest limit of magnetic blocks. Depths of the Curie Isotherm were also calculated. Results indicate that the depth to the Moho discontinuity in Jordan varies from 32 to 33 km in the northwest to 38 km in the southeast. The basement complex rocks outcrop on the surface in the southwest but lie at about 8 km in the northeast. The Curie Isotherm (585 °C) lies at a depth of about 10 km in the area east of the Dead Sea and dips southeastward towards the Al-Sirhan (Wadi Sirhan), southeast Jordan, where it is located at 35 km depth. Local isostasy of rock masses (blocks) in Jordan does not occur. Nevertheless, this does not rule out the possible existence of isostasy in a regional scale at greater depths within the mantle.     

EXPERIMENTAL AND FIELD STUDY ON MINING-PIT MIGRATION

1 INTRODUCTION Because of the large quantity of sand and gravel in their beds, rivers have always been considered as a major source of sand and gravel for civil works. Acceptable quality, ease of extraction and economy are some of the reasons could be mentioned. Unfortunately, specific laws and regulations regarding the safe in-stream mining have not been provided for users and officials. What should be taken into account are the effects of over-mining of sand and gravel, which can cause …     

Reconstruction of the diagenesis of the fluvial-lacustrine- deltaic sandstones and its influence on the reservoir quality evolution-- Evidence from Jurassic and Triassic sandstones, Yanchang Oil Field, Ordos Basin

The reservoir quality of Jurassic and Triassic fluvial and lacustrine-deltaic sandstones of the Yanchang Oil Field in the Ordos Basin is strongly influenced by the burial history and facies-related diagenetic events. The fluvial sandstones have a higher average porosity (14.8%) and a higher permeability (12.7×10?3 ?m2) than those of the deltaic sandstones (9.8% and 5.8 ×10?3 ?m2, respectively). The burial compaction, which resulted in 15% and 20% porosity loss for Jurassic and Triassic sandstones, respectively, is the main factor causing the loss of porosity both for the Jurassic and Triassic sandstones. Among the cements, carbonate is the main one that reduced the reservoir quality of the sandstones. The organic acidic fluid derived from organic matter in the source rocks, the inorganic fluid from rock-water reaction during the late diagenesis, and meteoric waters during the epidiagenesis resulted in the formation of dissolution porosity, which is the main reason for the enhancement of reservoir-quality.     

大港油田板深22井油气地球化学异常特征

根据板深22井中不同地球化学指标的背景含量和异常特征，重点探索和总结了不同油气层的化探指纹指标，并根据地表指纹指标的异常组合、配套关系及异常特征，对油气层的埋深进行了初步预测，为今后该地区地表开展预测油气藏埋深的工作提供了一定的地球化学依据。     

Surface effects of triggered fault slip on Reykjanes Peninsula, SW Iceland

Three large earthquakes (M_w>4.5) were triggered within 5 min, 85 km west of a M_w 6.5 earthquake in the South Iceland Seismic Zone (SISZ). We report on surface effects of these triggered earthquakes, which include fresh rupture, widespread rockfall, disrupted rockslides and block slides. Field data confirm that the earthquakes occurred along N-striking right-lateral strike-slip faults. Field data also support the conclusion from modeling of InSAR data that deformation from the second triggered event was more significant than for the other two. A major hydrological effect was the draining of water through an open fissure on a lake bed, lowering the lake level by greater than 4 m. Field relationships suggest that a component of aseismic slip could have been facilitated by water draining into the fault zone.     

场论理论在经济客体地位评价中的应用：以河南省城市地位为例

一个 经济客体地位的评价不能单从该经济客体本身来考虑，它还与评价区域周围其它观察经济客体有关，会受到其它经济客体的衬托作用。经济客全的地位应包括评价经济客体在其它经济客体的“势”和其它经济客体在评价经济客体处的“势”两部分。