河北省南部新石器时代人地关系研究

该文通过考古及古环境资料,分析了河北省南部地区新石器时代文化分布特点、古环境演变规律和人地关系,认为环境对于人类活动及人类文化发展的制约是主要的,环境不仅影响遗址的数量及分布位置,而且影响文化的性质及存续时间。在气候温暖期,河北省南部地区较多受中原文化及山东文化区系的影响,而在气候变冷或变干期,形成具有自己特色的文化或受北方文化影响较大。但人类活动已在一定程度上影响环境变化,刀耕火种的农业生产方式,使得局部地区的原始植被,特别是森林植被遭到较大程度的破坏,使得先民们不得不频繁迁移,因此在河北省南部,多数遗址文化层较薄且少有叠压现象。太行山区植被的破坏可能在新石器时代即已出现。     

环境恶化导致我国东部夏季频现北旱南涝

根据延伸的我国晴空总辐射量和夏季气候的关系,本文再次确认反映大气污染程度的晴空太阳辐射减少对我国近年来夏季频现的北旱南涝产生显著影响．同时。它还对随后2年以上的我国北方沙地面积的扩张起相当作用．较全面研究了近年来我国东部夏季北旱南涝加速发展的前期成因。认为这是包含空气质量,土地沙化在内的我国整个生态环境快速恶化并受到温室效应和“亚洲棕云”更大范围环境变化影响的综合结果．理应引起我们高度警惕．     

氧同位素第6期北印度洋的一次重大古海洋学事件

北印度洋赤道海岭的远洋沉积记录在氧同位素第6期的早期,即167～160ka期间,揭示出一次重大的古海洋学事件。在多项代用指标中,浮游有孔虫组合和通量的变化对该事件的反映最为强烈,因此将其命名为“第6期海洋生态环境严重恶化事件”。该事件以广适性种Globigerinita glutinata的高度发育、凉水种Neogloboquadrina pachyderma和Globigerina bulloides的异常增多、其他有孔虫常见种的普遍减少及有孔虫总量的大幅度降低为特征。结合其他代用指标和邻区资料,认为导致事件发生的主控因素在于超强的南亚冬季风及其所引发的表层水温降低和贫瘠的深层水团上涌。一般情况下,南亚冬季风对研究区环境的影响力远较夏季风弱,它的阶段性超常强化似乎总与青藏高原的强烈隆升有关。可推测,发生在第6期的生境恶化事件很可能是最近一次高原大规模构造抬升的产物。     

阿拉善左旗地区HFU-14航放铀异常特征及找矿意义

HFU-14航放铀异常是2017年航空物探测量新发现的,2017年11月份对该异常开展了地面查证工作。测量结果表明：该异常地表整体为砂土、砾石覆盖,局部见灰绿色、灰白色、黄褐色泥质砂土及少量石膏碎屑;地面伽玛总量背景值15~21Ur,最高值207 Ur,呈团块状异常;地面伽玛能谱U含量剖面呈尖峰异常,最高约174.67×10-6,背景值(1.4~5)×10-6,平面上总体呈北西向圆状及椭圆状展布;土壤氡浓度呈不规则团块状异常,分带明显,最大值为454.3kBq/m3,背景值6.09kBq/m3,单剖面峰背比多大于6.6;土壤地球化学U、Mo元素具有较高的变异系数和富集系数,呈强分异分布,并在土壤中次生富集强烈,局部富集形成矿化。综合物化探测量在异常地段圈定、类型划分、展布形态及成矿元素确定等方面组合合理,效果较好。综合分析该异常的物化探特征和区域铀成矿条件,初步查明HFU-14异常为表生（膏结岩）型铀矿化和深部砂岩型铀矿化共同作用形成,并为该区域铀矿勘查提供了有利的找矿信息。     

藏南洛扎地区洛扎断裂构造特征及其地质意义

藏南洛扎地区洛扎断裂属于区域上定日—洛扎断裂的东段部分,是喜马拉雅造山带中一条重要的断裂,但其总体研究程度较低。运用地质填图和构造解析的方法研究了洛扎断裂的几何形态、运动表现和活动历史等,讨论其在喜马拉雅造山带构造格局形成中的意义。主要认识如下:(1)洛扎断裂现今主要表现为一条规模大的脆性-脆韧性断层,SWW—NEE走向,高角度倾向NNW。断层带内发育劈理带、断层泥、构造角砾岩等。运动性质主体表现为正断层。(2)洛扎断裂的南北两侧地块具有显著不同的变形特征,南侧为平缓的大型背斜-向斜构造,北侧为近NWW—SEE走向的倒转褶皱-断层构造。(3)洛扎断裂经历了多期活动,中生代正断活动,古近纪逆冲活动,中新世韧性伸展,中新世晚期逆冲活动以及上新世—第四纪正断活动。现今断层展示的更多是最后一期活动的形迹。(4)依据其规模大、多期活动性、两盘构造变形与沉积的系统差异性等肯定了其作为构造分区断层而存在。(5)洛扎断裂和藏南拆离断层(STD)在研究区均有出露,局部二者出露线近于重合,但洛扎断裂以高角度断面切割了平缓的STD。洛扎断裂是比STD具有更悠久地质历史的区域性断层,只是后者中新世以来的活动性更多受到关注。     

南华北盆地中牟凹陷太原组-山西组页岩气成藏特征——以河南中牟区块ZDY2井为例

河南中牟区块ZDY2井海陆过渡相太原组和山西组页岩气层系地质特征分析表明:太原组和山西组富有机质页岩厚度均为77.5m,有机质类型主要为Ⅲ型,少量Ⅱ型;有机碳平均含量分别为2.18%和1.90%;有效孔隙度分别为1.53%和2.4%,现场解析平均含气量分别为1.32m~3/t和1.1m~3/t,其中太原组中部优质压裂层段平均含气量为1.56m~3/t;有机质成熟度Ro值在2.6%～3.4%之间;黏土矿物以伊利石和伊蒙混层为主。综合研究认为中牟区块太原组、山西组页岩气层系普遍含气,太原组中部页岩层段及山西组下部大占砂岩是有利勘探层位。通过ZDY2井太原组中部43.3m页岩层段压裂,获得日产天然气3 614m~3,南华北盆地海陆过渡相页岩气勘探取得重大进展。     

南方红壤区隐伏矿床地气试验研究——以广西德保铜锡矿区为例

为了了解地气测量方法在南方红壤区的应用效果和影响因素,对广西德保铜矿床进行了地气试验研究;结果表明,在南方红壤区,潮湿季节,地气测量没有效果,干旱季节,虽然地气测量具有一定效果,但地气中金属元素绝对含量较低,可能受到了深部碳酸盐地层和土壤的黏土性质的影响,需要进一步改进地气测量方法,使其能有效应用于南方红壤区隐伏矿勘查工作中。     

Buried channels provide keys to infer Quaternary stratigraphic and paleo-environmental changes:A case study from the west coast of India

High resolution shallow seismic data was acquired from inner continental shelf of Goa,west coast of India to map underlying stratigraphic and buried geomorphic features of shelf strata.Seismic data revealed characteristic channel incisions beneath 4-15 m thick sediment layer and corresponds to multi cycle incisions.Stratigraphic analysis of these incision signatures reveals three prominent subaerial unconformities S6,S7 and S9.These unconformities were exposed during the last glacial,penultimate glacial(MIS-6)and prior to penultimate glacial(MIS-8)periods.On the basis of interpreted age of subaerial unconformities and differences in their morphological features,observed channel incisions have been divided grossly into three phases of incision.Phase-1 incisions are older than ～330 kyr BP,whereas,incisions of Phase-2 and Phase-3 correspond to ～320-125 kyr BP and ～115-10 kyr BP respectively.Plan form of these incisions varied from a straight channel type to ingrown meander and then to anastomosing channel types.These channels meet at the confluence of present-day Mandovi and Zuari rivers.The confluence point has varied in due course of time because of cyclic incision and burial with repeated sea level fluctuations.The preserved main channel width varies from ～100 m to 1000 m.and maximum channel depth reaches up to ～35 m.Comparison of quantitative and qualitative morphologic results of different phases of incisions suggest that Phase-2 channels had ～33% more mean bank full discharge than that of the Phase-3 channels.Phase-2 incisions had been carved in higher hydraulic energy condition as compared to Phase-3 incisions implying that the Indian summer monsoon was better during formative stages of Phase-2 incisions.     

Origin of trondhjemite and albitite at the expense of A-type granite,Aravalli orogen,India:Evidence from new metasomatic replacement fronts

The A-type Harsora-Dadikar granites in the Alwar complex of northern Aravalli orogen,NW India provide evidence for subsolidus-requilibration of feldspars.They record three new discrete stages of albitisation,producing trondhjemite and albitite sequentially at the expense of original granite.Stage-Ⅰ metasomatism deanorthised the magmatic oligoclase and transformed the grey least-albitised granite to pinkish grey microcline-oligoclase granite.Stage-II converted the latter to trondhjemite by replacement of microcline to oligoclase.Stage-Ⅲ metasomatism led to the formation of albitite/albite granite from trondhjemite,where the metasomatically formed oligoclase was replaced by albite.This stage of metasomatism resulted in nearly complete disappearance of amphibole and biotite,producing a monomineralic rock(albitite),which is consistent with Korzhinskii theory of infiltration metasomatism.The reaction fronts delineating the Stage-Ⅱ and Stage-Ⅲ are sharp and easily discernible by their prominent color differences in Harsora on the outcrop scale.Chemically,the mineral transformations during three stages are manifested by the differential gains/losses in Na,K,Ca,Rb,Ba,Sr,Fe and Mg.The formation of albite,Cl-rich marialitic scapolite and Cl-rich amphibole in the albitised granites are suggestive of Naand Cl-brines as the metasomatising fluids.The fluid-rock interactions,which can significantly transform the pristine mineralogy of granitoids,should be carefully considered to avoid any misinterpretations about their petrological history.     

中国南方区域地球物理及深部构造的若干特征

本文在分析区域重磁场的基础上，由重磁资料结合深部地震和大地电磁测深资料所得的莫霍面、居里面、磁性体顶面及上地幔低阻层顶面深度，探讨我国南方地区的岩石圈和地壳厚度变化以及地热构造和基底构造特征，从而阐述了全区各层次的深部地质构造特征。