Deep Gold Exploration with SQUID TEM in the Qingchengzi Orefield, Eastern Liaoning, Northeast China

The Qingchengzi orefield is an important polymetallic ore concentration zone in the northern margin of the North China Craton (NCC). The region has significant metallogenic potential for deep mining. Many areas with gold mineralization have been found in the shallow area of Taoyuan–Xiaotongjiapuzi–Linjiasandaogou in the east of the Qingchengzi orefield. To assess the distribution of mineralization levels, we carried out deep exploration using the transient electromagnetic method (TEM). A superconductive quantum interference device (SQUID) magnetometer and a conventional induction coil were used for field data acquisition. The SQUID data inversion results reflect the bottom interface of the high-conductivity area, the fold state of the underlying dolomite marble stratum, and the deep structural characteristics of the syncline. Secondary crumples appear in the inversion results of the southern segment of TEM, which is inferred as a favorable area for deep gold mineralization. Negative values appear in the SQUID data of some stations, to varying degrees. This induced polarization phenomenon may be related to deep gold mineralization.

Iceberg disturbance to benthic communities in McMurdo Sound, Antarctica

On the continental shelf of the Antarctic the major disturbance to benthic ecosystems is from iceberg scouring; however, this is based on observations from the Peninsula region. We combine observation and experimentation in the McMurdo Sound region of the Ross Sea to determine if community recovery patterns there are similar to those in better-studied Antarctic regions, and if local immigration is an important factor in recovery dynamics. We found that regardless of habitat differences in depth, substrate, and oceanographic setting, iceberg disturbance strongly impacted benthic communities in McMurdo Sound. Notably, in shallow water (<30 m) where anchor ice is an annual disturbance, both the benthic communities and recovery processes were more variable than at deeper locations. A manipulative experiment performed in a shallow area indicated that recruitment might be more important than immigration to infaunal community recovery. We conclude that whilst disturbance frequency influences dominant epifauna, recovery from iceberg disturbance is a slow ecological progression that is dependent on the extremely inconsistent recruitment processes of the high Antarctic benthic ecosystem.

The Petroleum Systems from the Western Black Sea Basin, Romania

Although oil production has a long history in Romania, the offshore discoveries from the Western part of the Black Sea are still relatively newly developed and with further potential to be revealed. To find the best places for new wells, as well as making new oil field discoveries, it is very important to understand the petroleum system of the area. If the elements of the petroleum system are well understood, then the potential of the Black Sea will become bigger, as the complexity of the area will be acknowledged. Two major petroleum systems were discovered in the area, the thermogenic system, and the biogenic system. The thermogenic system is corresponding to the shallow area of the Black Sea, where current productive fields are, while the biogenic system is corresponding to the deeper area, currently being in the exploration stage. The purpose of this article is to present both petroleum systems from the Black Sea Romania, their elements, the evolution they had, and the major differences between the two.

STATUS PEMANFAATAN DAN UPAYA PENANGANAN HIU PAUS (Rhincodon typus) TERDAMPAR DI PERAIRAN INDONESIA

Hiu paus merupakan salah satu jenis hiu berukuran terbesar yang ada di dunia dan sudah masuk dalam daftar merah (Red List) untuk spesies terancam IUCN yaitu berstatus terancam punah (endangered). Untuk menjaga agar sumber daya hiu paus tetap terjamin populasinya, maka perlu adanya upaya pengelolaan untuk mendukung pelestarian spesies ini. Dalam makalah ini dibahas tentang strategi pemanfaatan dan penanganan hiu paus yang terdampar di perairan Indonesia. Metode penelitian yang digunakan adalah survei lapang dan wawancara yang dilakukan di Probolinggo dan Situbondo, Jawa Timur. Data dan informasi dihimpun dari penelusuran, dan penelahaan data dan informasi hasil penelitian serta laporan kegiatan yang terkait dengan hiu paus terdampar maupun keberadaannya di beberapa wilayah perairan di Indonesia. Hasil kajian menunjukkan bahwa terdapat enam wilayah perairan kemunculan hiu paus di Indonesia, baik yang menetap maupun yang tinggal sementara yaitu di perairan Teluk Cendrawasih, Talisayan, Kaimana, Teluk Gorontalo, Probolinggo, dan Banggai Kepulauan. Jumlah hiu paus yang berada di perairan Indonesia dan tersebar di beberapa wilayah perairan diperkirakan mencapai 253 ekor. dan teramati terbanyak berada di perairan Teluk Cendrawasih sebanyak 131 ekor. Kemunculan hiu paus maupun yang terdampar hampir terjadi setiap tahun dalam kondisi hidup terkadang keadaan mati. Koordinasi antara instansi terkait dan masyarakat dalam menangani dan menyelamatkan hiu paus yang terdampar maupun terjerat jaring saat ini sudah berjalan dengan baik. Terdapat 7 tahapan tata cara penanganan hiu paus terdampar dan ada 4 tahapan dalam rangka menunjang ekowisata hiu paus.Whale shark is one of the largest sharks in the world and on the red list IUCN for endangered species. To ensure that the population of whale sharks remains guaranteed, management efforts are needed to support the conservation of this species. The utilization and handling strategy of the whale sharks that stranded down in several Indonesian waters should be discussed seriously. Field survey method was applied and interview was done in Probolinggo and Situbondo, East Java. Data and information were collected and had been analyzed as well as activities reported that related to whale sharks stranded and their presence in several territorial waters Indonesia waters. The results of the study showed that there were six Indonesia waters area in which whale sharks appeared, both permanent and temporary, namely in Cendrawasih Bay, Talisayan, Kaimana, Gorontalo, Probolinggo, and Banggai Islands. The whale shark number that found in several Indonesian waters had been estimated about 253 individuals and the highest number was found 131 in Cendrawasih Bay. The appearances of whale shark and stranded in Indonesian waters has been almost every year and found in living or in such cases been in dead conditions that trapped in the shallow area. Coordination between related agencies and the community to carry out and rescuing whale sharks stranded or entangled in nets, has been in good progress. There were 7 stages of procedures for handling stranded whale sharks and 4 stages in order to support the ecotourism activities that related with appearances of whale sharks.

The Reproduction Ability of a Numerical Model for Simulating the Outflow Rate of Backfilling Materials from a Coastal Structure

In very shallow areas, the frequency by which coastal structures (like dikes and seawalls) are directly broken by large wave forces is low because large waves are broken in deeper areas. The main cause for such destruction is ground scour in front of the structures and outflow of backfilling materials by middle-scale waves; therefore, the scour and the outflow should be considered when designing a coastal structure in a very shallow area. In this paper, a numerical model consisting of CADMAS-SURF, which can calculate fluid motion in porous media, and empirical equations for simulating the outflow phenomena are introduced; thereafter, practical calculations on field cases in Thailand and Japan are demonstrated. Additionally, since the effects of wave periods and water depth to the outflow rate have never been clarified, hydraulic model experiments, empirical calculations using an existing formula, and numerical simulations are performed in order to examine these effects on the outflow rate. The simulated results using the numerical model align well with the experimental results. Moreover, both results show that the outflow rate is proportional to the wave period and inversely proportional to water depth.

A NUMERICAL CALCULATION FOR INTERNAL WAVES OVER TOPOGRAPHY

The internal waves propagating from the deep to shallow, and the shallow to deep, areas in the two-layer fluid systems, have been numerically simulated by solving the set of nonlinear equations, based on the variational principle in consideration of both the strong nonlinearity and strong dispersion of internal waves. The incident wave in the deep area, is the BO-type downward convex internal wave, which is the numerical solution obtained for the present fundamental equations. In the cases where the interface elevation is below, or equal to, the critical level in the shallow area, the disintegration of the internal waves occurs remarkably, leading to a long wave train. The lowest elevation of the interface, increases after its gradual decrease in the shallow area, where the interface is above the critical level, while the lowest elevation of the interface, increases through the internal-wave propagation in the shallow area, where the interface elevation is below, or equal to, the critical level, after its steep decrease around the boundary between the area over the upslope, and the shallow region.